Substrate for semiconductor device and manufacturing method thereof

1. Field of the Invention

The present invention relates to substrate for semiconductor device and manufacturing method thereof, and semiconductor device using the same and manufacturing method thereof.

2. Description of the Related Art

Generally, a semiconductor device includes a substrate having a plurality of electrically conductive patterns thereon, a semiconductor die located on the substrate, a plurality of conductive connecting means for electrically connecting the substrate to the semiconductor die, and an encapsulant for encapsulating the semiconductor die and the conductive connecting means. Here, a plurality of solder balls can be further fused to the substrate so as to electrically connect the semiconductor device to an external device.

Meanwhile, a relatively thick core layer is formed at the substrate of the semiconductor device, in order that a warpage is not generated during the manufacturing process of the semiconductor device. That is, the general substrate includes the core layer having a thickness of approximately 800 μm formed at the center thereof and a plurality of relatively thin build-up layers formed at top and bottom surfaces of the core layer. Here, a plurality of electrically conductive patterns is formed at the core layer and the build-up layers. Also, a plurality of via holes passes through the core layer and the build-up layers in order to electrically connect the electrically conductive pattern layers to each other.

However, since such substrate is comparatively thicker, there is a defect in that the thickness of the semiconductor device using the substrate becomes thicker. Also, because each electrically conductive pattern of the substrate is comparatively longer, there is a defect in that the electrical efficiency of the semiconductor device using the electrically conductive patterns is deteriorated. Especially, recent semiconductor devices have been required to have a wide bandwidth, fast data transferring, and higher density structure. However, it is difficult for the general substrate to implement recent trends thereof.

Here, it can solve the problems by eliminating the core layer from the substrate. However, where the core layer is eliminated from the substrate, since the warpage phenomenon is very higher during the manufacturing process of the semiconductor, it is difficult to manufacturer the semiconductor device. Also, it is difficult to manufacture and handle the substrate owing to the low stiffness thereof.

A substrate for a semiconductor device and a manufacturing thereof, and a semiconductor device using the same and a manufacturing method thereof are disclosed. For example, in the substrate according to the present invention, a core is eliminated, so that the substrate has a very thin thickness, as well, the length of electrically conductive patterns becomes shorter, whereby the electrical efficiency thereof is improved. Moreover, since a carrier having a stiffness of a predetermined strength is bonded on the substrate, it can prevent a warpage phenomenon during the manufacturing process of the semiconductor device. Furthermore, the carrier is removed from the substrate, whereby a solder ball fusing process or an electrical connecting process of the semiconductor die can be easily performed.

The present invention is best understood by reference to the following detailed description when read in conjunction with the accompanied drawings.

FIG. 1 is a sectional view of a substrate for a semiconductor device according to one embodiment of the present invention;

FIG. 1A through FIG. 1P are sectional views showing a fabrication method of the substrate for a semiconductor device according to one embodiment of the present invention where:

FIG. 1A illustrates a carrier providing operation;

FIG. 1B illustrates a first photo sensitive film providing operation;

FIG. 1C illustrates a first plating operation;

FIG. 1D illustrates a first photo sensitive film eliminating operation;

FIG. 1E illustrates a dielectric layer forming operation;

FIG. 1F illustrates a via hole forming operation;

FIG. 1G illustrates a second plating operation;

FIG. 1H illustrates a second photo sensitive film providing operation;

FIG. 1I illustrates a third plating operation;

FIG. 1J illustrates a second photo sensitive film eliminating operation;

FIG. 1K illustrates an etching operation;

FIG. 1L illustrates a solder mask printing operation;

FIG. 1M illustrates a solder mask exposing/developing operation;

FIG. 1N illustrates a third photo sensitive film providing operation;

FIG. 1O illustrates a fourth plating operation;

FIG. 1P illustrates a third photo sensitive film eliminating operation;

FIG. 2 is a sectional view of a semiconductor device according to one embodiment of the present invention;

FIG. 2A through FIG. 2E are sectional views showing a fabrication method of the semiconductor device according to one embodiment of the present invention where:

FIG. 2A illustrates a semiconductor die attaching operation;

FIG. 2B illustrates a wire bonding operation;

FIG. 2C illustrates an encapsulating operation;

FIG. 2D illustrates a carrier eliminating operation;

FIG. 2E illustrates a solder ball fusing operation;

FIG. 3 is a sectional view of a semiconductor device according to another embodiment of the present invention;

FIG. 3A through FIG. 3E are sectional views showing a fabrication method of the semiconductor device according to anther embodiment of the present invention where:

FIG. 3A illustrates a flip chip bonding operation;

FIG. 3B illustrates an underfilling operation;

FIG. 3C illustrates an encapsulating operation;

FIG. 3D illustrates a carrier eliminating operation;

FIG. 3E illustrates a solder ball fusing operation;

FIG. 4 is a sectional view of a substrate for a semiconductor device according to another embodiment of the present invention;

FIG. 4A through FIG. 4F is a flow chart showing a fabrication method of a semiconductor device according to another embodiment of the present invention;

FIG. 4A illustrates a multi layer forming operation;

FIG. 4B illustrates a solder mask printing operation;

FIG. 4C illustrates a solder mask exposing/developing operation;

FIG. 4D illustrates a photo sensitive film providing operation;

FIG. 4E illustrates a plating operation;

FIG. 4F illustrates a photo sensitive film eliminating operation;

FIG. 5 is a sectional view of a semiconductor device according to another embodiment of the present invention;

FIG. 5A through FIG. 5E are sectional views showing a fabrication method of a semiconductor device according to another embodiment of the present invention where:

FIG. 5A illustrates a flip chip bonding operation;

FIG. 5B illustrates an underfilling operation;

FIG. 5C illustrates an encapsulating operation;

FIG. 5D illustrates a carrier eliminating operation;

FIG. 5E illustrates a solder ball fusing operation;

FIG. 6A through FIG. 6E are sectional views showing a fabrication method of a semiconductor device according to another embodiment of the present invention where:

FIG. 6A illustrates a carrier eliminating operation;

FIG. 6B illustrates a flip chip bonding operation;

FIG. 6C illustrates an underfilling operation;

FIG. 6D illustrates an encapsulating operation;

FIG. 6E illustrates a solder ball fusing operation;

FIG. 7A through FIG. 7E are sectional views showing a fabrication method of a semiconductor device according to another embodiment of the present invention where:

FIG. 7A illustrates a carrier eliminating operation;

FIG. 7B illustrates a flip chip bonding operation;

FIG. 7C illustrates an underfilling operation;

FIG. 7D illustrates an encapsulating operation; and

FIG. 7E illustrates a solder ball fusing operation.

Common reference numerals are used throughout the drawings as well, detailed descriptions are used to indicate like elements.

Referring to FIG. 1 , a sectional view of a substrate 100 for a semiconductor device according to one embodiment of the present invention is illustrated.

As shown in FIG. 1 , the substrate 100 for a semiconductor device includes a carrier 110 having a predetermined stiffness, a dielectric layer 120 formed on the carrier 110 , a plurality of conductive lands 130 electrically connected to the carrier 110 at the inside of the dielectric layer 120 , a plurality of electrically conductive patterns 140 electrically connected to the conductive lands 130 at the surface of the dielectric layer 120 , and a solder mask 150 for covering the dielectric layer 120 and the electrically conductive patterns 140 , a predetermined area of each conductive pattern 140 being exposed to outside.

The carrier 110 is in the form of an approximately planar plate. The material of the carrier 110 may be a metal, a film or its equivalent, in order that a warpage is not generated during the manufacturing process of the semiconductor device. However, the present invention is not limited to any material of the carrier 110 . Moreover, in case of the metal as the material of the carrier 110 , the material of the carrier 110 may be a copper, an aluminum, a nickel or its equivalent. However, the present invention is not limited to any metal material of the carrier 110 .

The dielectric layer 120 of a predetermined thickness is formed on the surface of one side of the carrier 110 . The dielectric layer 120 includes a first surface 121 of an approximate planar surface bonded on the carrier 110 and a second surface 122 of an approximate planar surface opposed to the first surface 121 . Also, a plurality of via holes 123 of a predetermined depth is further formed at the second surface 122 of the dielectric layer 120 , in order to electrically connect the electrically conductive patterns 140 to the conductive lands 130 . The material of the dielectric layer 120 may be a prepreg and an ABF (Ajinomoto Buildup Film) of a low dielectric constant or its equivalent, in order to decrease the capacitance of the electrically conductive patterns 140 and so on. However, the present invention is not limited to any material of the dielectric layer 120 . Moreover, the thickness of the dielectric layer 120 is approximately 10˜150 μm, so that it has a very thin thickness in comparison with the conventional substrate having a core layer.

Each of conductive lands 130 formed at the inside of the dielectric layer 120 have a bottom surface flush (substantially coplanar) with the first surface 121 of the dielectric layer 120 . That is, the conductive lands 130 are electrically connected to the carrier 110 . Also, the conductive land 130 , that is, a copper layer 131 , a gold layer 132 , another copper layer 133 may be plated on the carrier 110 in order. However, the present invention is not limited to any material of the conductive land 130 .

The plurality of electrically conductive patterns 140 are formed at the second surface 122 of the dielectric layer 120 . Here, the plurality of electrically conductive patterns 140 is electrically connected to the conductive lands 130 through the via holes 123 formed at the dielectric layer 120 . The material of electrically conductive patterns 140 may be a copper or its equivalent. However, the present invention is not limited to any material of the electrically conductive patterns 140 .

The solder mask 150 is coated on the second surface 122 of the dielectric layer 120 in order to cover the electrically conductive patterns 140 . Here, a plurality of openings 151 are formed at the solder mask 150 , so that a predetermined area of each electrically conductive pattern 140 is exposed to outside. Also, a plurality of bonding pads 160 are formed at the electrically conductive patterns 140 exposed to outside through the openings 151 . A semiconductor die will be electrically connected to the bonding pad 160 in future. Also, the bonding pad 160 , that is, a nickel layer 161 and a gold layer 162 may be plated on the electrically conductive pattern 140 in order. However, the present invention is not limited to any material of the bonding pad 160 .

Referring to FIG. 1A through FIG. 1P , sectional views showing a fabrication method of the substrate 100 for a semiconductor device according to one embodiment of the present invention is illustrated.

As shown in the drawings, the fabrication method of the substrate 100 for a semiconductor device according to the present invention includes a carrier providing operation, a first photo sensitive film providing operation, a first plating operation, a first photo sensitive film eliminating operation, a dielectric layer forming operation, a via hole forming operation, a second plating operation, a second photo sensitive film providing operation, a third plating operation, a second photo sensitive film eliminating operation, an etching operation, a solder mask printing operation, a solder mask exposing/developing operation, a third photo sensitive film providing operation, a fourth plating operation, and a third photo sensitive film eliminating operation.

As shown in FIG. 1A , in the carrier providing operation, the carrier 110 of an approximately planar plate is provided. The material of the carrier 110 may be a metal, a film or its equivalent, in order that a warpage is not generated during the manufacturing process of the semiconductor device, as described above. However, the present invention is not limited to any material of the carrier 110 . Moreover, in case of the metal as the material of the carrier 110 , the material of the carrier 110 may be a copper, an aluminum, a nickel or its equivalent. However, the present invention is not limited to any metal material of the carrier 110 .

As shown in FIG. 1B , in the first photo sensitive film providing operation, the photo sensitive film 171 of a predetermined pattern is formed at the top surface and the bottom surface of the carrier 110 . That is, the photo sensitive film 171 , on which any pattern is not formed, is bonded or coated on the top surface and the bottom surface of the carrier 110 and then, only the photo sensitive film 171 having a predetermined pattern is left over the top surface of the carrier 110 through the exposing/developing process. Here, the predetermined region of the carrier 110 is exposed to outside through the photo sensitive film 171 .

As shown in FIG. 1C , in the first plating operation, the plurality of conductive lands 130 are formed. That is, the copper layer 131 , the gold layer 132 and another copper layer 133 are plated on the top surface of the carrier 110 exposed to outside through the photo sensitive film 171 in order, thereby forming the conductive lands 130 of a predetermined thickness.

As shown in FIG. 1D , in the first photo sensitive film eliminating operation, the photo sensitive film 171 left over the carrier 110 is eliminated by a chemical etching and the like. Here, like this, only the plurality of conductive lands 130 is left over the carrier 110 . Also, the carrier 110 except for the conductive lands 130 is exposed to outside.

As shown in FIG. 1E , in the dielectric layer forming operation, the dielectric layer 120 of a predetermined thickness is coated and hardened so as to cover the conductive lands 130 formed at the carrier 110 all together. Here, the material of the dielectric layer 120 may be a prepreg and an ABF (Ajinomoto Buildup Film) of a low dielectric constant or its equivalent, in order to decrease the capacitance of the electrically conductive patterns 140 and so on. However, the present invention is not limited to any material of the dielectric layer 120 . Moreover, the carrier 110 has an adequate stiffness, so that the warpage is not generated during the manufacturing process of the semiconductor device, thereby the dielectric layer 120 has very thin thickness of 10˜150 μm.

As shown in FIG. 1F , in the via hole forming operation, the via holes 123 of a predetermined depth are formed in such a manner that the conductive lands 130 formed at both the surface of the carrier 110 and the inside of the dielectric layer 120 are exposed to outside. That is, the dielectric layer 120 corresponding to the conductive lands 130 is eliminated by a laser drilling, a mechanical drilling or an etching and so on, so that the via holes 123 of a predetermined depth are formed. Here, the predetermined region of each conductive lands 130 is exposed to outside through the via holes 123 .

As shown in FIG. 1G , in the second plating operation, an electroless plating layer 172 , sometimes called a seed layer, of a thin thickness is formed at the surface of the dielectric layer 120 and the surface of the conducive lands 130 exposed to outside through the via holes 123 . The electroless plating layer 172 can be formed by means of a conventional electroless plating process. Also, the thickness of the electroless plating layer 172 is in the range of several μm.

As shown in FIG. 1H , in the second photo sensitive film providing operation, the photo sensitive film 173 of a predetermined pattern is formed at the surface of the electroless plating layer 172 again. Here, it is suited that the photo sensitive film 173 is not formed at the regions corresponding to the via holes 123 , so as to electrically connect the electrically conductive patterns 140 and the conductive lands 130 each other. Also, the photo sensitive film 173 , on which any pattern is not formed, is bonded or coated on the surface of the electroless plating layer 172 and then, only the photo sensitive film 173 having a predetermined pattern is left over the surface of the electroless plating layer 172 through the exposing/developing process. Here, the predetermined region of the electroless plating layer 172 is exposed to outside through the photo sensitive film 173 .

As shown in FIG. 1I , in the third plating operation, an electrolytic plating layer of a predetermined thickness is formed at the electroless plating layer exposed to outside through the photo sensitive film 173 . The electrolytic plating layer is the electrically conductive pattern 140 in fact. The electrolytic plating layer can be formed by means of a conventional electrolytic plating process, thereby obtaining the electrically conductive pattern 140 of desiring thickness.

As shown in FIG. 1J , in the second photo sensitive film eliminating operation, the photo sensitive film 173 formed on the electroless plating layer 172 is eliminated by a chemical etching and the like. Here, like this, the electroless plating layer 172 located at the lower portion of the photo sensitive film 173 is exposed to outside. Also, all of the electrically conductive patterns 140 continuously maintain a short status on account of the electroless plating layer 172 .

As shown in FIG. 1K , in the etching operation, all electroless plating layers 172 left between the electrically conductive patterns 140 are eliminated by the chemical etching process. Here, since the electroless plating layer 172 has very thin thickness of several μm, it can be easily eliminated through a weak acid.

As shown in FIG. 1L , in the solder mask printing operation, the solder mask 150 of a predetermined thickness is printed on the dielectric layer 120 in order to cover the electrically conductive patterns 140 . The material of the solder mask 150 may be photosensitivity or insensitivity. The solder mask 150 serves to prevent the oxidation of the electrically conductive patterns 140 and its damage from the external impact during the manufacturing process of the semiconductor device.

As shown in FIG. 1M , in the solder mask exposing/developing operation, a predetermined region of the solder mask 150 is eliminated by the exposing/developing process. That is, the plurality of openings 151 are formed at the solder mask 150 , so that a predetermined area of each electrically conductive pattern 140 is exposed to outside.

As shown in FIG. 1N , in the third photo sensitive film providing operation, the photo sensitive film 174 of a predetermined pattern is formed at the bottom surface of the carrier 110 . Here, since the photo sensitive film 174 serves to prevent the plating layer from formed at the bottom surface of the carrier 110 during the plating process, the material of the photo sensitive film 174 may not be photosensitivity.

As shown in FIG. 1O , in the fourth plating operation, the plurality of bonding pads 160 is formed at predetermined regions of the electrically conductive patterns 140 exposed to outside through the solder mask 150 . The plurality of bonding pads 160 can be formed by means of the electrolytic plating process. That is, the nickel layer 161 and the gold layer 162 may be plated on the electrically conductive pattern 140 of a predetermined region exposed to outside through the solder mask 150 , thereby forming the bonding pad 160 of a predetermined thickness. The bonding pad 160 serves to electrically connect with the semiconductor die during manufacturing process of the semiconductor device.

As shown in FIG. 1P , in the third photo sensitive film eliminating operation, the photo sensitive film 174 formed on the bottom surface of the carrier 110 is eliminated by a chemical etching and the like, thereby completing the substrate 100 according to the present invention. Here, the bottom surface of the carrier 110 is exposed to outside through the photo sensitive film elimination process.

Referring to FIG. 2 , a sectional view of a semiconductor device 200 according to one embodiment of the present invention is illustrated.

As shown in FIG. 2 , the semiconductor device 200 includes the above substrate 100 , a semiconductor die 210 bonded to the substrate 100 , a plurality of conductive connecting means 220 for electrically connecting the substrate 100 to the semiconductor die 200 , an encapsulant 230 for encapsulating the semiconductor die 200 and the conductive connecting means 220 , and a plurality of solder balls 240 fused to the substrate 100 .

Firstly, the substrate 100 is actually similar to that of FIG. 1 . However, the carrier 110 is removed from the substrate 100 and a predetermined region (the copper layer 131 ) is etched and eliminated. Accordingly, each conductive land 130 includes only the gold layer 132 and the copper layer 133 . As described above, the substrate includes the dielectric layer 120 , the plurality of conductive lands 130 , the plurality of electrically conductive patterns 140 , the bonding pads 160 , and the solder mask 150 . Since the structure and method of the substrate 100 is explained in full as described above, further description is omitted here.

The semiconductor die 210 is bonded to the surface of the solder mask 150 of the substrate 100 by means of an adhesive 201 . Here, a plurality of I/O pads 211 is formed at the top surface of the semiconductor die 210 .

The plurality of conductive connecting means 220 may be a conventional conductive wire. More concretely, it may be a gold wire, an aluminum wire or its equivalent. The connecting means 220 serves to electrically connect the bonding pads 160 of the substrate 100 to the I/O pads of the semiconductor die 210 each other.

The encapsulant 230 covers the semiconductor die 210 and the conductive connecting means 220 , so that it serves to protect them from an external impact. Here, the encapsulant 230 covers the whole top surface of the substrate 100 . Also, the material of the encapsulant 230 may be a plastic resin, a thermosetting resin, a ceramic, an epoxy molding compound or its equivalent. However, the present invention is not limited to any material of the encapsulant 230 .

The plurality of solder balls 240 is fused to the conductive lands 130 , that is, the gold layer 132 formed at the substrate 100 . The solder ball 240 serves to mechanically and electrically connect the semiconductor device 200 to an external device, as well known. The bottom surface of the conductive land 130 is not flush with the substrate 100 , that is, the bottom surface of the dielectric layer 120 . That is, the bottom surface of the conductive land 130 is located at the inside of the dielectric layer 120 . In other words, a recess 124 of a predetermined depth is formed at the inside of the dielectric layer 120 and the conductive land 130 is formed at the inside of the recess 124 . Accordingly, the solder ball 240 is combined with the recess 124 and fused to the conductive land 130 , the fusing status of the solder balls 240 is more strongly.

Referring to FIG. 2A through FIG. 2E , sectional views showing a fabrication method of the semiconductor device 200 according to one embodiment of the present invention is illustrated.

As shown in the drawings, the fabrication method of the semiconductor device 200 includes a substrate providing operation, a semiconductor die attaching operation, a connecting operation, an encapsulating operation, a carrier eliminating operation, and a solder ball fusing operation.

As shown in FIG. 2A , in the substrate providing operation and the semiconductor die attaching operation, the substrate 100 having the carrier 110 at bottom surface thereof is provided. The semiconductor die 210 is bonded to the top surface of the substrate 100 by means of the adhesive 201 . Here, The carrier 110 provides a predetermined stiffness, so that the warpage is not generated during the manufacturing process of the semiconductor device.

As shown in FIG. 2B , in the connecting operation, the bonding pads 160 of the substrate 100 and the I/O pads 211 of the semiconductor die 210 are electrically connected to each other by means of the connecting means 220 , that is, conductive wires.

As shown in FIG. 2C , in the encapsulating operation, the semiconductor die 210 and the conductive connecting means 220 are encapsulated by the encapsulant 230 . Here, the encapsulant 230 also, covers the whole top surface of the substrate 100 .

FIG. 2D shows carrier eliminating operation. If the carrier 110 is a metal, then the carrier 110 is completely eliminated by the chemical etching process. Accordingly, the bottom surface of the dielectric layer 120 of the substrate 100 is exposed to outside. Also, in the carrier eliminating operation by the chemical etching process, even the copper layer 131 of the conductive lands 130 of the substrate 100 is eliminated, so that the recess 124 of a predetermined depth is naturally formed at the dielectric layer 120 of the substrate 100 . At this time, only the gold layer 132 and the copper layer 133 as the conductive land 130 are left over the inside of the recess 124 .

However, if the carrier 110 is a film, then the carrier 110 is completely eliminated by the peeling off process (not shown). Accordingly, the bottom surface of the dielectric layer 120 of the substrate 100 is exposed to outside. Also, in the carrier eliminating operation by the peeling off process, the copper layer 131 of the conductive lands 130 of the substrate 100 is exposed to outside, unlike the above embodiment (not shown). That is, the recess 124 is not formed. Therefore, a bottom surface of the dielectric layer 120 may be flushed with a bottom surface of the copper layer 131 .

As shown in FIG. 2E , in the solder ball fusing operation, the plurality of solder balls 240 is fused to the recess 124 and the conductive lands 130 of the substrate 100 , thereby completing the semiconductor device 200 according to the present invention. The solder ball fusing operation includes a flux applying process for applying a sticky flux to the conductive lands 130 , an attaching process for temporarily attaching the solder balls 240 to the flux, and a reflowing process of high temperature.

Referring to FIG. 3 , a sectional view of a semiconductor device 300 according to another embodiment of the present invention is illustrated.

Here, the semiconductor device 300 of FIG. 3 is almost similar to that of FIG. 2 , the description of the similar parts is omitted here.

As shown in FIG. 3 , the semiconductor die 310 can be connected to the substrate 100 in the form of a flip chip. That is, after solder bumps 320 are fused to I/O pads 311 of the semiconductor die, in a state that the semiconductor die 310 turns upside down, the solder bumps 320 can be connected to the bonding pads 160 of the substrate 100 . Here, an underfill 330 is filling between the semiconductor die 310 and the substrate 100 , so as to prevent the oxidation of the solder bump 320 and strength bonding force between the semiconductor die 310 and the substrate 100 . Also, the peripheral of the semiconductor die 310 and the underfill 330 are encapsulated by an encapsulant 340 , it can protect the semiconductor die 310 and so forth from the external impact. Here, a plurality of solder balls 350 is fused to conductive lands 130 of the substrate 100 .

Referring to FIG. 3A through FIG. 3E , sectional views showing a fabrication method of the semiconductor device 300 according to another embodiment of the present invention is illustrated.

As shown in the drawings, the fabrication method of the semiconductor device 300 includes a substrate providing operation/a flip chip bonding operation, an underfilling operation, an encapsulating operation, a carrier eliminating operation, and a solder ball fusing operation.

As shown in FIG. 3A , in the substrate providing operation/the flip chip bonding operation, the substrate 100 having the carrier 110 at bottom surface thereof is provided. Thereafter, the semiconductor die 310 is bonded on the top surface of the substrate 100 in the form of a flip chip. That is, after the solder bumps 320 are fused to I/O pads 311 of the semiconductor die 310 , the solder bumps 320 are electrically connected to the bonding pads 160 of the substrate 100 in a state that the semiconductor die 310 turns upside down.

As shown in FIG. 3B , in the underfilling operation, the underfill 330 is injected into the gap between the semiconductor die 310 and the substrate 100 . Here, where the underfill 330 is injected into the gap between the semiconductor die 310 and the substrate 100 , the gap between the semiconductor die 310 and the substrate 100 completely fills with the underfill 330 through a capillary phenomenon.

As shown in FIG. 3C , in the encapsulating operation, the peripherals of the semiconductor die 310 and the underfill 330 are encapsulated by the encapsulant 340 .

FIG. 3D shows carrier eliminating operation. If the carrier 110 is a metal, then the carrier 110 completely eliminated by the chemical etching process. Accordingly, the bottom surface of the dielectric layer 120 of the substrate 100 is exposed to outside. Also, in the carrier eliminating operation by the chemical etching process, even the copper layer 131 of the conductive lands 130 of the substrate 100 is eliminated, so that the recess 124 of a predetermined depth is naturally formed at the dielectric layer 120 of the substrate 100 . At this time, only the gold layer 132 and the copper layer 133 as the conductive land 130 are left over the inside of the recess 124 .

However, if the carrier 110 is a film, then the carrier 110 is completely eliminated by the peeling off process (not shown). Accordingly, the bottom surface of the dielectric layer 120 of the substrate 100 is exposed to outside. Also, in the carrier eliminating operation by the peeling off process, the copper layer 131 of the conductive lands 130 of the substrate 100 is exposed to outside, unlike the above embodiment (not shown). That is, the recess 124 is not formed. Therefore, a bottom surface of the dielectric layer 120 may be flushed with a bottom surface of the copper layer 131 .

As shown in FIG. 3E , in the solder ball fusing operation, the carrier 110 is eliminated and the plurality of solder balls 350 is fused to the conductive lands 130 exposed to outside through the dielectric layer 120 , thereby completing the semiconductor device 300 according to the present invention.

Referring to FIG. 4 , a sectional view of a substrate 400 for a semiconductor device according to another embodiment of the present invention is illustrated.

As shown in FIG. 4 , the substrate 400 for semiconductor device includes a carrier 410 having a predetermined stiffness, a first dielectric layer 420 a having first electrically conductive patterns 440 a and conductive lands 430 , a second dielectric layer 420 b having second electrically conductive patterns 440 b , a third dielectric layer 420 c having third electrically conductive patterns 440 c , a fourth dielectric layer 420 d having fourth electrically conductive patterns 440 d and bonding pads 460 , and a solder mask 450 .

The carrier 410 is in the form of an approximately planar plate. The material of the carrier 410 may be a metal, a ceramics, a glass or its equivalent, in order that the warpage is not generated during the manufacturing process of the semiconductor device. Moreover, in case of the metal as the material of the carrier 410 , the material of the carrier 410 may be a copper, an aluminum, a nickel or its equivalent.

The first dielectric layer 420 a of a predetermined thickness is formed on the top surface of the carrier 410 . The plurality of conductive lands 430 connected to the carrier 410 is formed at the inside of the first dielectric layer 420 a . The conductive land 430 , that is, a copper layer 431 , a gold layer 432 , another copper layer 433 may be plated on the carrier 410 in order. Also, the plurality of first electrically conductive patterns 440 a is formed at the top surface of the first dielectric layer 420 a and is electrically connected to the conductive lands 430 through via holes 423 a formed at the first dielectric layer 420 a.

The second dielectric layer 420 b of a predetermined thickness is formed on the top surface of the first dielectric layer 420 a . Also, the plurality of second electrically conductive patterns 440 b is formed at the top surface of the second dielectric layer 420 b and is electrically connected to the first electrically conductive patterns 440 a through via holes 423 b formed at the second dielectric layer 420 b.

The third dielectric layer 420 c of a predetermined thickness is formed on the top surface of the second dielectric layer 420 b . Also, the plurality of third electrically conductive patterns 440 c is formed at the top surface of the third dielectric layer 420 c and is electrically connected to the second electrically conductive patterns 440 b through via holes 423 c formed at the third dielectric layer 420 c.

The fourth dielectric layer 420 d of a predetermined thickness is formed on the top surface of the third dielectric layer 420 c . Also, the plurality of fourth electrically conductive patterns 440 d is formed at the top surface of the fourth dielectric layer 420 d and is electrically connected to the third electrically conductive patterns 440 c through via holes 423 d formed at the fourth dielectric layer 420 d . Moreover, the bonding pads 460 including a nickel layer 461 and the gold layer 462 may be plated on predetermined regions of the fourth electrically conductive pattern 440 d formed at the fourth dielectric layer 420 d.

Meanwhile, in the illustrated case, the dielectric layer has only four layers. However, the present invention is not limited to the dielectric layer having only four layers. In accordance with the present invention, the dielectric layer may have three, four or more dielectric layer.

The solder mask 450 is formed on the top surface of the fourth dielectric layer 420 d in order to cover the fourth electrically conductive patterns 440 d . Accordingly, the solder mask 450 serves to protect the fourth electrically conductive patterns 440 d from the external impact. However, the solder mask 450 does not cover the bonding pads 460 . That is, the bonding pads 460 are exposed to outside through the openings 451 .

Referring to FIG. 4A through FIG. 4F , sectional views showing a fabrication method of the semiconductor device according to another embodiment of the present invention is illustrated.

As shown in the drawings, the fabrication method of the semiconductor device includes a multi layer forming operation, a solder mask printing operation, a solder mask exposing/developing operation, a photo sensitive film providing operation, a plating operation, and a photo sensitive film eliminating operation.

As shown in FIG. 4A , in the multi layer forming operation, the first dielectric layer 420 a having the first electrically conductive patterns 440 a and conductive lands 430 , the second dielectric layer 420 b having the second electrically conductive patterns 440 b , the third dielectric layer 420 c having the third electrically conductive patterns 440 c , and the fourth dielectric layer 420 d having the fourth electrically conductive patterns 440 d are laminated on the carrier 410 in order. Here, the number of the layer may be less than 4 or more than 5. However, the present invention is not limited to the number of the layer.

As shown in FIG. 4B , in the solder mask printing operation, the solder mask 450 of a predetermined thickness is printed on the fourth dielectric layer 420 d in order to cover the fourth electrically conductive patterns 440 d formed at the surface of the fourth dielectric layer 420 d . The material of the solder mask 450 may be photosensitivity or insensitivity. The solder mask 450 serves to prevent the oxidation of the fourth electrically conductive patterns 440 d and its damage from the external impact during the manufacturing process of the semiconductor device.

As shown in FIG. 4C , in the solder mask exposing/developing operation, a predetermined region of the solder mask 450 is eliminated by the exposing/developing process. That is, the plurality of openings 451 is formed at the solder mask 450 , so that a predetermined area of each fourth electrically conductive pattern 440 d is exposed to outside.

As shown in FIG. 4D , in the photo sensitive film providing operation, the photo sensitive film 471 of a predetermined thickness is formed at the bottom surface of the carrier 410 . Here, since the photo sensitive film 471 serves to prevent the plating layer from being formed at the bottom surface of the carrier 410 during the plating process, the material of the photo sensitive film 471 may not be photosensitivity.

As shown in FIG. 4E , in the plating operation, the plurality of bonding pads 460 is formed at predetermined regions of the fourth electrically conductive patterns 440 d exposed to outside through the solder mask 450 . The plurality of bonding pads 460 can be formed by means of the electrolytic plating process. That is, the nickel layer 461 and the gold layer 462 may be plated on the fourth electrically conductive pattern 440 d of a predetermined region exposed to outside through the opening 451 of the solder mask 450 , thereby forming the bonding pad 460 of a predetermined thickness. The bonding pad 460 serves to electrically connect with the semiconductor die 310 during manufacturing process of the semiconductor device.

As shown in FIG. 4F , in the photo sensitive film eliminating operation, the photo sensitive film 471 formed on the bottom surface of the carrier 410 is eliminated by a chemical etching and the like thereby completing the substrate 400 according to the present invention. Here, the bottom surface of the carrier 410 is exposed to outside through the photo sensitive film elimination process.

Referring to FIG. 5 , a sectional view of a semiconductor device 500 according to another embodiment of the present invention is illustrated.

As shown in FIG. 5 , a semiconductor die 510 can be connected to the above substrate 400 in the form of a flip chip. That is, I/O pads 511 of the semiconductor die 510 are electrically connected to the bonding pads 460 formed at the fourth dielectric layer 420 d of the substrate 400 by means of solder bumps 520 . Here, an underfill 530 is filling between the semiconductor die 510 and the fourth dielectric layer 420 d . Also, the underfill 530 covers the solder bumps 520 , the solder mask 450 , the bonding pads 460 and the fourth dielectric layer 420 d corresponding to the lower portion of the semiconductor die 510 .

In the meantime, the peripheral of the semiconductor die 510 and the underfill 530 are encapsulated by an encapsulant 540 . Here, the encapsulant 540 covers the solder mask 450 formed at the fourth dielectric layer 420 d.

In the illustrated case, the semiconductor die 510 is connected to the substrate 400 in the form of the flip chip. However, the semiconductor die 510 can be connected to the substrate 400 by means of a wire bonding method.

Also, a plurality of solder balls 550 is fused to the substrate 400 , that is, the conductive lands 430 formed at the first dielectric layer 420 a . Here, The solder ball 550 serves to mechanically and electrically connect the semiconductor device 500 to the external device. Also, each conductive land 430 includes a gold layer 432 and only one copper layer 433 .

Referring to FIG. 5A through FIG. 5E , sectional views showing a fabrication method of the semiconductor device 500 according to another embodiment of the present invention is illustrated.

As shown in the drawings, the fabrication method of the semiconductor device 500 includes a substrate providing operation/a flip chip bonding operation, an underfilling operation, an encapsulating operation, a carrier eliminating operation and a solder ball fusing operation.

As shown in FIG. 5A , in the substrate providing operation/the flip chip bonding operation, the substrate 400 of the multi layer having the carrier 410 at bottom surface thereof is provided. Thereafter, the semiconductor die 510 is bonded on the top surface of the substrate 400 in the form of the flip chip. That is, That is, after the solder bumps 520 are fused to the I/O pads 511 of the semiconductor die 510 , the solder bumps 520 are electrically connected to the bonding pads 460 of the substrate 400 in a state that the semiconductor die 510 turns upside down.

As shown in FIG. 5B , in the underfilling operation, the underfill 530 is injected into the gap between the semiconductor die 510 and the substrate 400 . Here, where the underfill 530 is injected into the gap between the semiconductor die 510 and the substrate 400 . The gap between the semiconductor die 510 and the substrate 400 completely fills with the underfill 530 through a capillary phenomenon.

As shown in FIG. 5C , in the encapsulating operation, the peripherals of the semiconductor die 510 and the underfill 530 are encapsulated by the encapsulant 540 . Also, the encapsulant 540 covers the solder mask 450 of the substrate 400 .

FIG. 5D shows carrier eliminating operation. If the carrier 410 is a metal, then the carrier 410 completely eliminated by the chemical etching process. Accordingly, the bottom surface of the dielectric layer 420 a of the substrate 400 is exposed to outside. Also, in the carrier eliminating operation by the chemical etching process, even the copper layer 431 of the conductive lands 430 of the substrate 400 is eliminated, so that the recess 424 of a predetermined depth is naturally formed at the dielectric layer 420 a of the substrate 400 . At this time, only the gold layer 432 and the copper layer 433 as the conductive land 430 are left over the inside of the recess 424 .

However, if the carrier 410 is a film, then the carrier 410 is completely eliminated by the peeling off process (not shown). Accordingly, the bottom surface of the dielectric layer 420 a of the substrate 400 is exposed to outside. Also, in the carrier eliminating operation by the peeling off process, the copper layer 431 of the conductive lands 430 of the substrate 400 is exposed to outside, unlike the above embodiment (not shown). That is, the recess 424 is not formed. Therefore, a bottom surface of the dielectric layer 420 a may be flushed with a bottom surface of the copper layer 431 .

As shown in FIG. 5E , in the solder ball fusing operation, the carrier 410 is eliminated and the plurality of solder balls 550 is fused to the conductive lands 430 exposed to outside through the first dielectric layer 420 a , thereby completing the semiconductor device 500 according to the present invention.

In the meantime, the semiconductor device 500 may be manufactured by another method.

That is, referring to FIG. 6A through FIG. 6E , sectional views showing another fabrication method of the semiconductor device 500 according to the present invention is illustrated.

As shown in the drawings, the fabrication method of the semiconductor device 500 includes a carrier eliminating operation, a flip chip bonding operation, an underfilling operation, an encapsulating operation, and a solder ball fusing operation.

FIG. 6A shows carrier eliminating operation. If the carrier 410 is a metal, then the carrier 410 completely eliminated by the chemical etching process. Accordingly, the bottom surface of the dielectric layer 420 a of the substrate 400 is exposed to outside. Also, in the carrier eliminating operation by the chemical etching process, even the copper layer 431 of the conductive lands 430 of the substrate 400 is eliminated, so that the recess 424 of a predetermined depth is naturally formed at the dielectric layer 420 a of the substrate 400 . At this time, only the gold layer 432 and the copper layer 433 as the conductive land 430 are left over the inside of the recess 424 .

However, if the carrier 410 is a film, then the carrier 410 is completely eliminated by the peeling off process (not shown). Accordingly, the bottom surface of the dielectric layer 420 a of the substrate 400 is exposed to outside. Also, in the carrier eliminating operation by the peeling off process, the copper layer 431 of the conductive lands 430 of the substrate 400 is exposed to outside, unlike the above embodiment (not shown). That is, the recess 424 is not formed. Therefore, a bottom surface of the dielectric layer 420 a may be flushed with a bottom surface of the copper layer 431 .

As shown in FIG. 6B , in the flip chip bonding operation, the substrate, the semiconductor die 510 is bonded on the top surface of the substrate 400 in the form of the flip chip. That is, That is, after the solder bumps 520 are fused to the I/O pads 511 of the semiconductor die 510 , the solder bumps 520 are electrically connected to the bonding pads 460 of the substrate 400 in a state that the semiconductor die 510 turns upside down.

As shown in FIG. 6C , in the underfilling operation, the underfill 530 is injected into the gap between the semiconductor die 510 and the substrate 400 . Here, where the underfill 530 is injected into the gap between the semiconductor die 510 and the substrate 400 , the gap between the semiconductor die 510 and the substrate 400 completely fills with the underfill 530 through a capillary phenomenon.

As shown in FIG. 6D , in the encapsulating operation, the peripherals of the semiconductor die 510 and the underfill 530 are encapsulated by the encapsulant 540 . Also, the encapsulant 540 covers the solder mask 450 of the substrate 400 .

As shown in FIG. 6E , in the solder ball fusing operation, the plurality of solder balls 550 is fused to the conductive lands 430 exposed to outside through the first dielectric layer 420 a , thereby completing the semiconductor device 500 according to the present invention.

In the meantime, the semiconductor device 500 may be manufactured by another method. In other words, dissimilarly with the above methods, the semiconductor die 510 can be bonded on the bottom surface of the substrate 400 in the form of the flip chip and the plurality of solder balls 550 can be the top surface of the substrate 400 .

That is, referring to FIG. 7A through FIG. 7E , sectional views showing fabrication method of another semiconductor device 500 ′ according to the present invention is illustrated.

As shown in the drawings, the fabrication method of the semiconductor device 500 ′ includes a carrier eliminating operation, a flip chip bonding operation, an underfilling operation, an encapsulating operation, and a solder ball fusing operation.

FIG. 7A shows carrier eliminating operation. If the carrier 410 is a metal, then the carrier 410 is completely eliminated by the chemical etching process. Accordingly, the bottom surface of the dielectric layer 420 a of the substrate 400 is exposed to outside. Also, in the carrier eliminating operation by the chemical etching process, even the copper layer 431 of the conductive lands 430 of the substrate 400 is eliminated, so that the recess 424 of a predetermined depth is naturally formed at the dielectric layer 420 a of the substrate 400 . At this time, only the gold layer 432 and the copper layer 433 as the conductive land 430 are left over the inside of the recess 424 .

However, if the carrier 410 is a film, then the carrier 410 is completely eliminated by the peeling off process (not shown). Accordingly, the bottom surface of the dielectric layer 420 a of the substrate 400 is exposed to outside. Also, in the carrier eliminating operation by the peeling off process, the copper layer 431 of the conductive lands 430 of the substrate 400 is exposed to outside, unlike the above embodiment (not shown). That is, the recess 424 is not formed. Therefore, a bottom surface of the dielectric layer 420 a may be flushed with a bottom surface of the copper layer 431 .

As shown in FIG. 7B , in the flip chip bonding operation, the substrate, the semiconductor die 510 is bonded on the conductive lands 430 , that is, the gold layer 432 exposed to outside through the recesses 424 in the form of the flip chip. That is, after the solder bumps 520 are fused to the I/O pads 511 of the semiconductor die 510 , the solder bumps 520 are electrically connected to the conductive lands 430 of the substrate 400 .

As shown in FIG. 7C , in the underfilling operation, the underfill 530 is injected into the gap between the semiconductor die 510 and the substrate 400 . Here, where the underfill 530 is injected into the gap between the semiconductor die 510 and the first dielectric layer 420 a corresponding to the semiconductor die 510 , the gap between the semiconductor die 510 and the first dielectric layer 420 a completely fills with the underfill 530 through a capillary phenomenon. Here, the underfill 530 completely covers the solder bumps 520 , thereby preventing the oxidation of the solder bump 520 .

As shown in FIG. 7D , in the encapsulating operation, the semiconductor die 510 and the underfill 530 are encapsulated by the encapsulant 540 . Also, the encapsulant 540 covers the bottom surface of the first dielectric layer 420 a , not the solder mask.

As shown in FIG. 7E , in the solder ball fusing operation, the plurality of solder balls 550 is fused to the bonding pads 460 , not the conductive lands 430 . That is, the plurality of solder balls 550 , not the semiconductor die 510 is fused to the bonding pads 460 exposed to outside through the openings 451 of the solder mask 450 and formed at the fourth dielectric layer 420 d . Here, after a flux is applied on the bonding pads 460 d , the solder balls are temporarily attached on the bonding pads 460 d and then, the solder balls are thoroughly fixed to the bonding pads 460 d by means of a reflow process of a high temperature, thereby completing the semiconductor device 500 ′.

This disclosure provides exemplary embodiments of the present invention. The scope of the present invention is not limited by these exemplary embodiments. Numerous variations, whether explicitly provided for or implied by the specification, such as variations in structure, dimension and type of material and the manufacturing process may be implemented by one who is skilled in the art, in view of this disclosure.