Embedded package structure module with high-density electrical connections and method for making the same

1. Field of the Invention

The present invention relates to an embedded package structure module and a method for making the same, and particularly relates to an embedded package structure module with high-density electrical connections and a method for making the same.

2. Description of the Related Art

In the typical printer technology, a laser is used as a light source in a printer head to scan and transfer the printing information as light signals to a rotating drum in order to generate electrostatic latent images formed on the rotating drum. Moreover, the printing method further includes a toner absorbing step, a transferring step, a hot pressing step, an electrostatic discharging step etc. to reach printing. However, a laser printer head of the prior art has many optical components, and the mechanism of the laser printer head is complex and the optical path of the laser printer head is very long. Hence, the optical structure is quite complex and difficult to reduce in size when using a laser as light source. Therefore, the current trend is toward using light emitting diodes to replace lasers as the light sources in printer heads, which can simplify the optical structure.

Thereby, it is a requirement to reduce the volume of each light emitting diode so as to increase the resolution of the printer. More light emitting diodes can be fitted per unit area on the printer head when the volume of each light emitting diode is reduced. According to the typical packaging method, a highly precise packaging apparatus is required to arrange the light emitting diode arrays and the driver integrated circuits so that they are exactly parallel to each other in a printed circuit board. Then, a wire bonding process is performed to form about 5000 wires between the light emitting diode arrays and the driver integrated circuits if the resolution of the printer is 600 dpi (dots per inch) of A4 size paper. The driver integrated circuits drive the light emitting diode arrays through these wires.

A highly exact and dense wire bonding process in the foregoing method increases the difficulty of the packaging process. This reduces the product yield and indirectly raises the manufacturing costs. Moreover, reducing the volume of the light emitting diodes in order to increase the resolution of the printer, further increases the packaging difficulty.

In order to solve above-mentioned problem, the prior art provides a method for making a package structure module with high-density electrical connections, including: etching at least one concave groove on a top surface of the drive IC structure; receiving an LED array structure in the at least one concave groove; and forming a conductive connections electrically connected between the drive IC structure and the LED array structure via semiconductor procedures in order to achieve high-density electrical connections.

However, the method for making a package structure module with high-density electrical connections of the prior art is complex, and particularly relates to the semiconductor procedures. Hence, time and cost are increased. Therefore, a new package structure and method thereof is required to resolve the foregoing problems.

One particular aspect of the present invention is to provide an embedded package structure module with high-density electrical connections and a method for making the same. The embedded package structure module is an LED (Light Emitting Diode) array structure module, and the LED array structure module is a light exposure module that can be applied to an EPG (Electrophotography) printer.

The features of the present invention include (1) forming at least one concave groove on a top surface of a drive IC structure; (2) receiving an LED array structure in the at least one concave groove (there is a height difference between the drive IC structure and the LED array structure); (3) forming concave grooves on a lateral wall of the drive IC structure and a lateral wall of the LED array structure for electrically connection (the lateral wall of the drive IC structure is close to the lateral wall of the LED array structure); (4) electroplating solder materials onto the drive IC structure; (5) slanting the PCB by a predetermined angle during a reflow process in order to make the solder materials flow to the LED array structure on a low position to connect to the pads of the LED array structure. Hence, the present invention can reach a high-density electrical connection with 600˜1200 dip. Therefore, the present invention can reduce product size, material cost, and manufacturing cost due to high-density electrical connection.

In order to reach the above-mentioned aspects, the present invention provides an embedded package structure module with high-density electrical connections, including: a drive IC structure, an LED array structure and a plurality of conductive structures. The drive IC structure has at least one concave groove. The LED array structure is received in the at least one concave groove of the drive IC structure, and the LED array structure has a plurality of second open grooves formed on its lateral wall and close to the drive IC structure. The conductive structures respectively traverse the second open grooves in order to make the conductive structures electrically connect between the drive IC structure and the LED array structure.

In order to reach the above-mentioned aspects, the present invention provides a method for making an embedded package structure module with high-density electrical connections, including: providing a drive IC structure with at least one concave groove and an LED array structure received in the at least one concave groove of the drive IC structure, wherein the drive IC structure has a plurality of conductive materials formed on its top surface, the LED array structure has a plurality of second open grooves formed on its lateral wall and close to the drive IC structure, and the height of the top surface of the LED array structure is larger than the height of the top surface of the drive IC structure; electrically disposing the drive IC structure on a substrate; slanting the substrate by a predetermined angle during a reflow process in order to make the conductive materials change into liquid conductive materials and make the liquid conductive materials traverse the second open grooves to flow to the LED array structure; and cooling the liquid conductive materials to form a plurality of conductive structures electrically connected between the drive IC structure and the LED array structure.

Therefore, the present invention does not need to use a wire-bonding process as in the prior art that requires a long time and the present invention can solve the problem of the complex method for making a package structure module with high-density electrical connections of the prior art. (particularly relates to the semiconductor procedures). Hence, the present invention not only can reduce product size, material cost, and manufacturing cost, but also increases production speed.

It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed. Other advantages and features of the invention will be apparent from the following description, drawings and claims.

The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawings, in which:

FIG. 1 is a flowchart of a method for making an embedded package structure module with high-density electrical connections according to the first embodiment of the present invention;

FIGS. 1 A 1 to 1 D 2 are cross-sectional views of an embedded package structure module with high-density electrical connections according to the first embodiment of the present invention, at different stages of the packaging processes, respectively;

FIG. 2 is a flowchart of a method for making an embedded package structure module with high-density electrical connections according to the second embodiment of the present invention;

FIGS. 2 A 1 to 2 D 2 are cross-sectional views of an embedded package structure module with high-density electrical connections according to the second embodiment of the present invention, at different stages of the packaging processes, respectively;

FIG. 3 is a flowchart of a method for making an embedded package structure module with high-density electrical connections according to the third embodiment of the present invention;

FIGS. 3 A 1 to 3 D 2 are cross-sectional views of an embedded package structure module with high-density electrical connections according to the third embodiment of the present invention, at different stages of the packaging processes, respectively;

FIG. 4 is a flowchart of a method for making an embedded package structure module with high-density electrical connections according to the fourth embodiment of the present invention; and

FIGS. 4 A 1 to 4 D 2 are cross-sectional views of an embedded package structure module with high-density electrical connections according to the fourth embodiment of the present invention, at different stages of the packaging processes, respectively.

Referring to FIGS. 1 and 1 A 1 to 1 D 2 , FIG. 1 shows a flowchart of a method for making an embedded package structure module with high-density electrical connections according to the first embodiment of the present invention, and FIGS. 1 A 1 to 1 D 2 show cross-sectional views of an embedded package structure module with high-density electrical connections according to the first embodiment of the present invention, at different stages of the packaging processes, respectively.

The first embodiment of the present invention provides a method for making an embedded package structure module with high-density electrical connections. The method includes following steps: referring to FIGS. 1 , 1 A 1 and 1 A 2 (FIG. 1 A 2 shows a partial top view of FIG. 1 A 1 ), the step of S 100 is: providing a drive IC structure 1 a with at least one concave groove 100 a and an LED array structure 2 a received in the at least one concave groove 100 a of the drive IC structure 1 a , the drive IC structure 1 a having a plurality of first open grooves 10 a formed on its lateral wall 1 a W, the drive IC structure 1 a having a plurality of conductive materials 3 a 1 formed on its top surface, and the LED array structure 2 a having a plurality of second open grooves 20 a formed on its lateral wall 2 a W and respectively close to the first open grooves 10 a.

Moreover, the LED array structure 2 a is received in the at least one concave groove 100 a of the drive IC structure 1 a by an adhesive element 200 a . The height of the top surface of the LED array structure is larger than the height of the top surface of the drive IC structure. Each first open groove 10 a and each second open groove 20 a are respectively formed on the lateral wall 1 a W of the drive IC structure 1 a and the lateral wall 2 a W of the LED array structure 2 a via etching. The at least one concave groove 100 a are formed via etching. In addition, each first open groove 10 a or each second open groove 20 a has a depth of between 50 μm and 100 μm. The conductive materials 3 a 1 are formed on the drive IC structure 1 a by plating, and the conductive materials 3 a 1 can be solders.

Furthermore, the step of S 102 is: electrically disposing the drive IC structure 1 a on a substrate 4 a . The substrate 4 a can be a PCB (Printed Circuit Board). The substrate 4 a has at least one input/output pad 40 a . In addition, at least one conductive element 5 a is connected between the drive IC structure 1 a and the at least one input/output pad 40 a of the substrate 4 a.

Moreover, the drive IC structure 1 a has a plurality of drive IC pads 11 a formed on its top surface and a plurality of first conductive traces 12 a . The drive IC pads 11 a of the drive IC structure 1 a correspond to the first open grooves 10 a and each first conductive trace 12 a is formed between each corresponding drive IC pad 11 a and each corresponding first open groove 10 a . Each first conductive trace 12 a is formed on the top surface of the drive IC structure 1 a and is formed on the lateral wall 10 a W of the corresponding first open groove 10 a of the drive IC structure 1 a . In addition, the conductive materials 3 a 1 are respectively formed on the drive IC pads 11 a of the drive IC structure 1 a.

Furthermore, the LED array structure 2 a has a plurality of LED pads 21 a formed on its top surface and a plurality of second conductive traces 22 a . The LED pads 21 a of the LED array structure 2 a correspond to the second open grooves 20 a and each second conductive trace 22 a is formed between each corresponding LED pad 21 a and each corresponding second open groove 20 a . Each second conductive trace 22 a is formed on the top surface of the LED array structure 2 a and is formed on the lateral wall 20 a W of the corresponding second open groove 20 a of the LED array structure 2 a . In addition, the LED array structure 2 a has a plurality of LED dies 24 a connected to the LED pads 21 a via a plurality of third conductive traces 23 a , respectively.

With regard to the first embodiment of the present invention, the drive IC pads 11 a are arranged in a sawtooth shape in order to increase the density of the drive IC pads 11 a , and the LED pads 21 a are arranged in a line shape. However, the arrangement of the drive IC pads 11 a and the LED pads 21 a does not used to limit the present invention. Any type of arrangement of the pads is protected in the present invention. For example, the drive IC pads 11 a are arranged in a line shape, and the LED pads 21 a are arranged in a sawtooth shape; alternatively, the drive pads 11 a and the LED pads 21 a are arranged in a line shape or in a sawtooth shape.

Moreover, referring to FIGS. 1 , 1 B and 1 C, the step of S 104 is: slanting the substrate 4 a by a predetermined angle θ during a reflow process in order to make the conductive materials 3 a 1 (as shown in FIG. 1B ) change into liquid conductive materials 3 a 2 (as shown in FIG. 1C ) and make the liquid conductive materials 3 a 2 traverse the first open grooves 10 a and the second open grooves 20 a in sequence to flow to the LED array structure 2 a . In other words, each liquid conductive material 3 a 2 flows along the corresponding first conductive trace 12 a , traverses the corresponding first open groove 10 a and the corresponding second open groove 20 a , flows along the lateral wall 20 a W (each liquid conductive material 3 a 2 flows upward and downward along the lateral wall 20 a W) of the corresponding second open groove 20 a and the corresponding second conductive trace 22 a in sequence, and then reaches the corresponding LED pads 21 a ; Alternatively, each liquid conductive material 3 a 2 flows along the corresponding first conductive trace 12 a , traverses the corresponding first open groove 10 a and the corresponding second open groove 20 a , and then reaches the corresponding second conductive trace 22 a that is formed on the lateral wall 20 a W of the corresponding second open groove 20 a.

Furthermore, referring to FIGS. 1 , 1 D 1 and 1 D 2 (FIG. 1 D 2 shows a partial top view of FIG. 1 D 1 ), the step of S 106 is: cooling the liquid conductive materials 3 a 2 to form a plurality of conductive structures 3 A electrically connected between the drive IC structure 1 a and the LED array structure 2 a . In addition, each conductive structure 3 A is divided into three portions that are a first portion 3 A 1 , a second portion 3 A 2 and a third portion 3 A 3 , and the second portion 3 A 2 is electrically connected between the first portion 3 A 1 and the third portion 3 A 3 . The first portion 3 A 1 is formed on the corresponding drive IC pad 11 a and the corresponding first conductive trace 12 a . The second portion 3 A 2 traverses the corresponding first open groove 10 a and the corresponding second open groove 20 a in sequence and is formed on the corresponding second conductive trace 22 a formed on the lateral wall 20 a W of the corresponding second open groove 20 a . The third portion 3 A 3 are formed on the corresponding second conductive trace 22 a in order to electrically connect with the corresponding LED pad 21 a . Hence, each conductive structure 3 A is electrically connected between the corresponding drive IC pad 11 a of the drive IC structure 1 a and the corresponding LED pad 21 a of the LED array structure 2 a.

Referring to FIGS. 2 and 2 A 1 to 2 D 2 , FIG. 2 shows a flowchart of a method for making an embedded package structure module with high-density electrical connections according to the second embodiment of the present invention, and FIGS. 2 A 1 to 2 D 2 show cross-sectional views of an embedded package structure module with high-density electrical connections according to the second embodiment of the present invention, at different stages of the packaging processes, respectively.

The second embodiment of the present invention provides a method for making an embedded package structure module with high-density electrical connections. The method includes following steps: referring to FIGS. 2 , 2 A 1 and 2 A 2 (FIG. 2 A 2 shows a partial top view of FIG. 2 A 1 ), the step of S 200 is: providing a drive IC structure 1 b with at least one concave groove 100 b and an LED array structure 2 b received in the at least one concave groove 100 b of the drive IC structure 1 b , the drive IC structure 1 b having a plurality of first open grooves 10 b formed on its lateral wall 1 b W, the drive IC structure 1 b having a plurality of conductive materials 3 b 1 formed on its top surface, the LED array structure 2 b having a plurality of second open grooves 20 b formed on its lateral wall 2 b W and respectively close to the first open grooves 10 b , and the LED array structure 2 b having an insulation layer 25 b formed on it top surface.

Moreover, the height of the top surface of the LED array structure 2 b is larger than the height of the top surface of the drive IC structure 1 b . Each first open groove 10 b and each second open groove 20 b are respectively formed on the lateral wall 1 b W of the drive IC structure 1 b and the lateral wall 2 b W of the LED array structure 2 b via etching. The at least one concave groove 100 b are formed via etching. In addition, each first open groove 10 b or each second open groove 20 b has a depth of between 50 μm and 100 μm. The conductive materials 3 b 1 are formed on the drive IC structure 1 b by plating, and the conductive materials 3 b 1 can be solders.

Furthermore, the step of S 202 is: electrically disposing the drive IC structure 1 b on a substrate 4 b . The substrate 4 b can be a PCB (Printed Circuit Board). The substrate 4 b has at least one input/output pad 40 b . In addition, at least one conductive element 5 b is connected between the drive IC structure 1 b and the at least one input/output pads 40 b of the substrate 4 b.

Moreover, the drive IC structure 1 b has a plurality of drive IC pads 11 b formed on its top surface and a plurality of first conductive traces 12 b . The drive IC pads 11 b of the drive IC structure 1 b correspond to the first open grooves 10 b and each first conductive trace 12 b is formed between each corresponding drive IC pad 11 b and each corresponding first open groove 10 b . Each first conductive trace 12 b is formed on the top surface of the drive IC structure 1 b and is formed on the lateral wall 10 b W of the corresponding first open groove 10 b of the drive IC structure 1 b . In addition, the conductive materials 3 b 1 are respectively formed on the drive IC pads 11 b of the drive IC structure 1 b.

Furthermore, the LED array structure 2 b has a plurality of LED pads 21 b formed on its top surface and a plurality of second conductive traces 22 b . The LED pads 21 b of the LED array structure 2 b correspond to the second open grooves 20 b and each second conductive trace 22 b is formed between each corresponding LED pad 21 b and each corresponding second open groove 20 b . Each second conductive trace 22 b is formed on the top surface of the LED array structure 2 b and is formed on the lateral wall 20 b W of the corresponding second open groove 20 b of the LED array structure 2 b . In addition, the LED array structure 2 b has a plurality of LED dies 24 b connected to the LED pads 21 b via a plurality of third conductive traces 23 b , respectively.

In addition, the insulation layer 25 b formed on the top surface of the LED array structure 2 b exposes the LED dies 24 b and external sides 220 b of the second conductive traces 22 b.

With regard to the second embodiment of the present invention, the drive IC pads 11 b are arranged in a sawtooth shape in order to increase the density of the drive IC pads 11 b , and the LED pads 21 b are arranged in a line shape.

Moreover, referring to FIGS. 2 , 2 B and 2 C, the step of S 204 is: slanting the substrate 4 b by a predetermined angle θ during a reflow process in order to make the conductive materials 3 b 1 (as shown in FIG. 2B ) change into liquid conductive materials 3 b 2 (as shown in FIG. 2C ) and make the liquid conductive materials 3 b 2 traverse the first open grooves 10 b and the second open grooves 20 b in sequence to flow to the external sides 220 b of the second conductive traces 22 b . In other words, each liquid conductive material 3 b 2 flows along the corresponding first conductive trace 12 b , traverses the corresponding first open groove 10 b and the corresponding second open groove 20 b , flows along the lateral wall 20 b W (each liquid conductive material 3 b 2 flows upward and downward along the lateral wall 20 b W) of the corresponding second open groove 20 b , and then reaches the external side 220 b of the corresponding second conductive trace 22 b (the liquid conductive materials 3 b 2 is stopped on the external sides 220 b of the second conductive traces 22 b via the insulation layer 25 b ); Alternatively, each liquid conductive material 3 b 2 flows along the corresponding first conductive trace 12 b , traverses the corresponding first open groove 10 b and the corresponding second open groove 20 b , and then reaches the corresponding second conductive trace 22 b that is formed on the lateral wall 20 b W of the corresponding second open groove 20 b.

Furthermore, referring to FIGS. 2 , 2 D 1 and 2 D 2 (FIG. 2 D 2 shows a partial top view of FIG. 2 D 1 ), the step of S 206 is: cooling the liquid conductive materials 3 b 2 to form a plurality of conductive structures 3 B electrically connected between the drive IC structure 1 b and the LED array structure 2 b . In addition, each conductive structure 3 B is divided into a first portion 3 B 1 and a second portion 3 B 2 electrically connected to each other. The first portion 3 B 1 is formed on the corresponding drive IC pad 11 b and the corresponding first conductive trace 12 b . The second portion 3 B 2 traverses the corresponding first open groove 10 b and the corresponding second open groove 20 b in sequence and is formed on its lateral wall 20 b W of the corresponding second open groove 20 b and the external side 220 b of the corresponding second conductive trace 22 b due to the obstruction of the insulation layer 25 b . Hence, each conductive structure 3 B is electrically connected between the corresponding drive IC pad 11 b of the drive IC structure 1 b and the external side 220 b of the corresponding second conductive trace 22 b in order to make each corresponding drive IC pad 11 b electrically connect with the corresponding LED pad 21 b.

Referring to FIGS. 3 and 3 A 1 to 3 D 2 , FIG. 3 shows a flowchart of a method for making an embedded package structure module with high-density electrical connections according to the third embodiment of the present invention, and FIGS. 3 A 1 to 3 D 2 show cross-sectional views of an embedded package structure module with high-density electrical connections according to the third embodiment of the present invention, at different stages of the packaging processes, respectively.

The third embodiment of the present invention provides a method for making an embedded package structure module with high-density electrical connections. The method includes following steps: referring to FIGS. 3 , 3 A 1 and 3 A 2 (FIG. 3 A 2 shows a partial top view of FIG. 3 A 1 ), the step of S 300 is: providing a drive IC structure 1 c with at least one concave groove 100 c and an LED array structure 2 c received in the at least one concave groove 100 c of the drive IC structure 1 c , the drive IC structure 1 c has a plurality of first open grooves 10 c formed on its lateral wall 1 c W, the LED array structure 2 c having a plurality of second open grooves 20 c formed on its lateral wall 2 c W and respectively close to the first open grooves 10 c , and the LED array structure 2 c has a plurality of conductive materials 3 c 1 formed on its top surface.

Moreover, the LED array structure 2 c is received in the at least one concave groove 100 c of the drive IC structure 1 c by an adhesive element 200 c . The height of the top surface of the LED array structure is smaller than the height of the top surface of the drive IC structure. Each first open groove 10 c and each second open groove 20 c are respectively formed on the lateral wall 1 c W of the drive IC structure 1 c and the lateral wall 2 c W of the LED array structure 2 c via etching. The at least one concave groove 100 c are formed via etching. In addition, each first open groove 10 c or each second open groove 20 c has a depth of between 50 μm and 100 μm. The conductive materials 3 c 1 are formed on the drive IC structure 1 c by plating, and the conductive materials 3 c 1 can be solders.

Furthermore, the step of S 302 is: electrically disposing the drive IC structure 1 c on a substrate 4 c . The substrate 4 c can be a PCB (Printed Circuit Board). The substrate 4 c has at least one input/output pad 40 c . In addition, at least one conductive element 5 c is connected between the drive IC structure 1 c and the at least one input/output pad 40 c of the substrate 4 c:

Moreover, the drive IC structure 1 c has a plurality of drive IC pads 11 c formed on its top surface and a plurality of first conductive traces 12 c . The drive IC pads 11 c of the drive IC structure 1 c correspond to the first open grooves 10 c and each first conductive trace 12 c is formed between each corresponding drive IC pad 11 c and each corresponding first open groove 10 c . Each first conductive trace 12 c is formed on the top surface of the drive IC structure 1 c and is formed on the lateral wall 10 c W of the corresponding first open groove 10 c of the drive IC structure 1 c.

Furthermore, the LED array structure 2 c has a plurality of LED pads 21 c formed on its top surface and a plurality of second conductive traces 22 c . The LED pads 21 c of the LED array structure 2 c correspond to the second open grooves 20 c and each second conductive trace 22 c is formed between each corresponding LED pad 21 c and each corresponding second open groove 20 c . Each second conductive trace 22 c is formed on the top surface of the LED array structure 2 c and is formed on the lateral wall 20 c W of the corresponding second open groove 20 c of the LED array structure 2 c . In addition, the conductive materials 3 c 1 are respectively formed on the LED pads 21 C of the LED array structure 1 c . The LED array structure 2 c has a plurality of LED dies 24 c connected to the LED pads 21 c via a plurality of third conductive traces 23 c , respectively.

With regard to the first embodiment of the present invention, the drive IC pads 11 c are arranged in a sawtooth shape in order to increase the density of the drive IC pads 11 c , and the LED pads 21 c are arranged in a line shape.

Moreover, referring to FIGS. 3 , 3 B and 3 C, the step of S 304 is: slanting the substrate 4 c by a predetermined angle θ during a reflow process in order to make the conductive materials 3 c 1 (as shown in FIG. 3B ) change into liquid conductive materials 3 c 2 (as shown in FIG. 3C ) and make the liquid conductive materials 3 c 2 traverse the second open grooves 20 c and the first open grooves 10 c in sequence to flow to the LED array structure 2 c . In other words, each liquid conductive material 3 c 2 flows along the corresponding second conductive trace 22 c , traverses the corresponding second open groove 20 c and the corresponding first open groove 10 c , flows along the lateral wall 10 c W (each liquid conductive material 3 c 2 flows upward and downward along the lateral wall 10 c W) of the corresponding first open groove 10 c and the corresponding first conductive trace 12 c in sequence, and then reaches the corresponding drive IC pads 11 c ; Alternatively, each liquid conductive material 3 c 2 flows along the corresponding second conductive trace 22 c , traverses the corresponding second open groove 20 c and the corresponding first open groove 10 c , and then reaches the corresponding first conductive trace 12 c that is formed on the lateral wall 10 c W of the corresponding first open groove 10 c.

Furthermore, referring to FIGS. 3 , 3 D 1 and 3 D 2 (FIG. 3 D 2 shows a partial top view of FIG. 3 D 1 ), the step of S 306 is: cooling the liquid conductive materials 3 c 2 to form a plurality of conductive structures 3 C electrically connected between the drive IC structure 1 c and the LED array structure 2 c . In addition, each conductive structure 3 C is divided into three portions that are a first portion 3 C 1 , a second portion 3 C 2 and a third portion 3 C 3 , and the second portion 3 C 2 is electrically connected between the first portion 3 C 1 and the third portion 3 C 3 . The first portion 3 C 1 is formed on the corresponding LED pad 21 c and the corresponding second conductive trace 22 c . The second portion 3 C 2 traverses the corresponding second open groove 20 c and the corresponding first open groove 10 c in sequence and is formed on the corresponding first conductive trace 12 c formed on the lateral wall 10 c W of the corresponding first open groove 10 c . The third portion 3 C 3 is formed on the corresponding first conductive trace 12 c in order to electrically connect with the corresponding drive IC pad 11 c . Hence, each conductive structure 3 C is electrically connected between the corresponding drive IC pad 11 c of the drive IC structure 1 c and the corresponding LED pad 21 c of the LED array structure 2 c.

Referring to FIGS. 4 and 4 A 1 to 4 D 2 , FIG. 4 shows a flowchart of a method for making an embedded package structure module with high-density electrical connections according to the third embodiment of the present invention, and FIGS. 4 A 1 to 4 D 2 show cross-sectional views of an embedded package structure module with high-density electrical connections according to the fourth embodiment of the present invention, at different stages of the packaging processes, respectively.

The fourth embodiment of the present invention provides a method for making an embedded package structure module with high-density electrical connections. The method includes following steps: referring to FIGS. 4 , 4 A 1 and 4 A 2 (FIG. 4 A 2 shows a partial top view of FIG. 4 A 1 ), the step of S 400 is: providing a drive IC structure 1 d with at least one concave groove 100 d and an LED array structure 2 d received in the at least one concave groove 100 d of the drive IC structure 1 d , the drive IC structure 1 d having a plurality of first open grooves 10 d formed on its lateral wall 1 d W, the drive IC structure 1 d having a plurality of conductive materials 3 d 1 formed on its top surface, the LED array structure 2 d having a plurality of second open grooves 20 d formed on its lateral wall 2 d W and respectively close to the first open grooves 10 d , and the LED array structure 2 d having an insulation layer 25 d formed on it top surface.

Moreover, the LED array structure 2 d is received in the at least one concave groove 100 d of the drive IC structure 1 d by an adhesive element 200 d . The height of the top surface of the LED array structure 2 d is smaller than the height of the top surface of the drive IC structure 1 d . Each first open groove 10 d and each second open groove 20 d are respectively formed on the lateral wall 1 d W of the drive IC structure 1 d and the lateral wall 2 d W of the LED array structure 2 d via etching. The at least one concave groove 100 d are formed via etching. In addition, each first open groove 10 d or each second open groove 20 d has a depth of between 50 μm and 100 μm. The conductive materials 3 d 1 are formed on the drive IC structure 1 d by plating, and the conductive materials 3 d 1 can be solders.

Furthermore, the step of S 402 is: electrically disposing the drive IC structure 1 d on a substrate 4 d . The substrate 4 d can be a PCB (Printed Circuit Board). The substrate 4 d has at least one input/output pad 40 d . In addition, at least one conductive element 5 d is connected between the drive IC structure 1 d and the at least one input/output pad 40 d of the substrate 4 d.

Moreover, the drive IC structure 1 d has a plurality of drive IC pads 1 d formed on its top surface and a plurality of first conductive traces 12 d . The drive IC pads 1 d of the drive IC structure 1 d correspond to the first open grooves 10 d and each first conductive trace 12 d is formed between each corresponding drive IC pad 11 d and each corresponding first open groove 10 d . Each first conductive trace 12 d is formed on the top surface of the drive IC structure 1 d and is formed on the lateral wall 10 d W of the corresponding first open groove 10 d of the drive IC structure 1 d.

Furthermore, the LED array structure 2 d has a plurality of LED pads 21 d formed on its top surface and a plurality of second conductive traces 22 d . The LED pads 21 d of the LED array structure 2 d correspond to the second open grooves 20 d and each second conductive trace 22 d is formed between each corresponding LED pad 21 d and each corresponding second open groove 20 d . Each second conductive trace 22 d is formed on the top surface of the LED array structure 2 d and is formed on the lateral wall 20 d W of the corresponding second open groove 20 d of the LED array structure 2 d . In addition, the conductive materials 3 d 1 are respectively formed on the LED pads 21 d of the LED array structure 2 d . The LED array structure 2 d has a plurality of LED dies 24 d connected to the LED pads 21 d via a plurality of third conductive traces 23 d , respectively.

In addition, the insulation layer 25 d formed on the top surface of the drive IC structure 1 d is used to expose the drive IC pads 1 d and external sides 120 d of the first conductive traces 12 d.

With regard to the fourth embodiment of the present invention, the drive IC pads 1 d are arranged in a sawtooth shape in order to increase the density of the drive IC pads 11 d , and the LED pads 21 d are arranged in a line shape.

Moreover, referring to FIGS. 4 , 4 B and 4 C, the step of S 404 is: slanting the substrate 4 d by a predetermined angle θ during a reflow process in order to make the conductive materials 3 d 1 (as shown in FIG. 4B ) change into liquid conductive materials 3 d 2 (as shown in FIG. 4C ) and make the liquid conductive materials 3 d 2 traverse the second open grooves 20 d and the first open grooves 10 d in sequence to flow to the external sides 120 d of the first conductive traces 12 d . In other words, each liquid conductive material 3 d 2 flows along the corresponding second conductive trace 22 d , traverses the corresponding second open groove 20 d and the corresponding first open groove 10 d , flows along the lateral wall 10 d W (each liquid conductive material 3 d 2 flows upward and downward along the lateral wall 10 d W) of the corresponding first open groove 10 d , and then reaches the external side 120 d of the corresponding first conductive trace 12 d (the liquid conductive materials 3 d 2 is stopped on the external sides 120 d of the first conductive traces 12 d via the insulation layer 25 d ); Alternatively, each liquid conductive material 3 d 2 flows along the corresponding second conductive trace 22 d , traverses the corresponding second open groove 20 d and the corresponding first open groove 10 d , and then reaches the corresponding first conductive trace 12 d that is formed on the lateral wall 10 d W of the corresponding first open groove 10 d.

Furthermore, referring to FIGS. 4 , 4 D 1 and 4 D 2 (FIG. 4 D 2 shows a partial top view of FIG. 4 D 1 ), the step of S 406 is: cooling the liquid conductive materials 3 d 2 to form a plurality of conductive structures 3 D electrically connected between the drive IC structure 1 d and the LED array structure 2 d . In addition, each conductive structure 3 D is divided into a first portion 3 D 1 and a second portion 3 D 2 electrically connected to each other. The first portion 3 D 1 is formed on the corresponding LED pad 21 d and the corresponding second conductive trace 22 d . The second portion 3 D 2 traverses the corresponding second open groove 20 d and the corresponding first open groove 10 d in sequence and is formed on its lateral wall 10 d W of the corresponding first open groove 10 d and the external side 120 d of the corresponding first conductive trace 12 d due to the obstruction of the insulation layer 25 d . Hence, each conductive structure 3 D is electrically connected between the corresponding LED pad 21 d of the LED array structure 1 d and the external side 120 d of the corresponding first conductive trace 12 d in order to make each corresponding drive IC pad 11 d electrically connect with the corresponding LED pad 21 d.

In addition, according to designer's requirements, one structure that has the conductive materials thereon does not need to form open grooves. In other words, such as the first embodiment, the first open grooves 10 a do not need to form on the drive IC structure 1 a firstly. Hence, the liquid conductive materials 3 a 2 only needs to respectively traverse the second open grooves 20 a of the LED array structure 2 a , the conductive structures 3 B are formed between the drive IC structure 1 a and the LED array structure 2 a . Such as the third embodiment, the second open grooves 20 c do not need to form on the LED array structure 2 c firstly. Hence, the liquid conductive materials 3 c 2 only needs to respectively traverse the first open grooves 10 c of the drive IC structure 1 c , the conductive structures 3 C are formed between the drive IC structure 1 c and the LED array structure 2 c.

In conclusion, the embedded package structure module is an LED array structure module, and the LED array structure module is a light exposure module that can be applied to an EPG (Electrophotography) printer.

The features of the present invention include (1) forming at least one concave groove on a top surface of a drive IC structure; (2) receiving an LED array structure in the at least one concave groove (there is a height difference between the drive IC structure and the LED array structure); (3) forming concave grooves on a lateral wall of the drive IC structure and a lateral wall of the LED array structure for electrically connection (the lateral wall of the drive IC structure is close to the lateral wall of the LED array structure); (4) electroplating solder materials onto the drive IC structure; (5) slanting the PCB by a predetermined angle during a reflow process in order to make the solder materials flow to the LED array structure on a low position to connect to the pads of the LED array structure. Hence, the present invention can reach a high-density electrical connection with 600˜1200 dip. Therefore, the present invention can reduce product size, material cost, and manufacturing cost due to high-density electrical connection.

In conclusion, the present invention does not need to use a wire-bonding process as in the prior art that requires a long time and the present invention can solve the problem of the complex method for making a package structure module with high-density electrical connections of the prior art (particularly relates to the semiconductor procedures). Hence, the present invention not only can reduce product size, material cost, and manufacturing cost, but also increases production speed.

Although the present invention has been described with reference to the preferred best molds thereof, it will be understood that the invention is not limited to the details thereof. Various substitutions and modifications have been suggested in the foregoing description, and others will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims.