Manufacturing method of semiconductor device

A manufacturing method of a semiconductor device comprising the steps of:nforming a first electrode layer over a substrate having an insulating surface;forming a first insulating layer over the first electrode layer;forming an oxide semiconductor layer over the first insulating layer;dehydrating or dehydrogenating the oxide semiconductor layer as a first treatment;forming a second electrode layer and a third electrode layer over the oxide semiconductor layer;forming a second insulating layer over the oxide semiconductor layer;forming a third insulating layer over the second insulating layer;forming a fourth insulating layer over the third insulating layer;forming a second gate electrode layer over the second insulating layer; andperforming a heat treatment as a second treatment, after forming the second insulating layer,wherein the second insulating layer contains silicon, oxygen and nitrogen,wherein the third insulating layer contains aluminum and oxygen,wherein the fourth insulating layer contains silicon and nitrogen, andwherein a treatment temperature of the second treatment is lower than a treatment temperature of the first treatment.

A manufacturing method of a semiconductor device comprising the steps of:nforming a first gate electrode layer over a substrate having an insulating surface;forming a first insulating layer over the first gate electrode layer;forming an oxide semiconductor layer over the first insulating layer;dehydrating or dehydrogenating the oxide semiconductor layer as a first treatment;forming a source electrode layer and a drain electrode layer over the oxide semiconductor layer;forming a second insulating layer over the oxide semiconductor layer;forming a third insulating layer over the second insulating layer;forming a fourth insulating layer over the third insulating layer;forming a second gate electrode layer over the second insulating layer; andperforming a heat treatment as a second treatment, after forming the second insulating layer,wherein the second insulating layer contains silicon, oxygen and nitrogen,wherein the third insulating layer contains aluminum and oxygen,wherein the fourth insulating layer contains silicon and nitrogen, andwherein a thickness of the oxide semiconductor layer is greater than or equal to 5 nm and less than or equal to 200 nm, andwherein a treatment temperature of the second treatment is lower than a treatment temperature of the first treatment.

A manufacturing method of a semiconductor device comprising the steps of:nforming a first gate electrode layer over a substrate having an insulating surface;forming a first insulating layer over the first gate electrode layer;forming an oxide semiconductor layer over the first insulating layer;dehydrating or dehydrogenating the oxide semiconductor layer as a first treatment;forming a source electrode layer and a drain electrode layer over the oxide semiconductor layer;forming a second insulating layer over the oxide semiconductor layer;forming a third insulating layer over the second insulating layer;forming a fourth insulating layer over the third insulating layer;forming a second gate electrode layer over the second insluating layer; andperforming a heat treatment as a second treatment, after forming the second insulating layer,wherein the second insulating layer contains silicon, oxygen and nitrogen,wherein the third insulating layer contains aluminum and oxygen,wherein the fourth insulating layer contains silicon and nitrogen,wherein a thickness of the oxide semiconductor layer is greater than or equal to 5 nm and less than or equal to 200 nm,wherein a treatment temperature of the second treatment is lower than a treatment temperature of the first treatment,wherein the oxide semiconductor layer contains indium, gallium and zinc, andwherein the first insulating layer is a stacked-layer structure of a first layer containing silicon and nitrogen and a second layer containing silicon and oxygen.