公开(公告)号：US20170236844A1

公开(公告)日：2017-08-17

申请号：US15427695

申请日：2017-02-08

Applicant: Semiconductor Energy Laboratory Co., Ltd.

Inventor： Shunpei YAMAZAKI ,  Kenichi OKAZAKI ,  Masashi TSUBUKU ,  Haruyuki BABA ,  Sachie SHIGENOBU ,  Emi KOEZUKA

IPC: H01L27/12 ,  H01L29/417 ,  H01L29/423 ,  H01L29/786

CPC classification number: H01L27/1225 ,  H01L29/41733 ,  H01L29/42384 ,  H01L29/4908 ,  H01L29/78633 ,  H01L29/78648 ,  H01L29/7869 ,  H01L29/78696

Abstract: In a transistor including an oxide semiconductor, a variation in electrical characteristics is suppressed and reliability is improved. A semiconductor device includes a transistor. The transistor includes a first gate electrode, a first insulating film over the first gate electrode, an oxide semiconductor film over the first insulating film, a second insulating film over the oxide semiconductor film, a second gate electrode over the second insulating film, and a third insulating film over the oxide semiconductor film and the second gate electrode. The oxide semiconductor film includes a channel region overlapping with the second gate electrode, a source region in contact with the third insulating film, and a drain region in contact with the third insulating film. The first gate electrode and the second gate electrode are electrically connected to each other. A difference between a minimum value and a maximum value of the field-effect mobility in the case where the field-effect mobility in a saturation region of the transistor is measured.