US Patent 10192995 Semiconductor device and manufacturing method thereof

A semiconductor device includes a semiconductor, a first conductor, a second conductor, a third conductor, a fourth conductor, a first insulator, a second insulator, a third insulator, and a fourth insulator. The first conductor and the semiconductor partly overlap with each other with the first insulator positioned therebetween. The second conductor and the third conductor have regions in contact with the semiconductor. The semiconductor has a region in contact with the second insulator. The fourth insulator has a first region and a second region. The first region is thicker than the second region. The first region has a region in contact with the second insulator. The second region has a region in contact with the third insulator. The fourth conductor and the second insulator partly overlap with each other with the fourth insulator positioned therebetween.