Semiconductor device

• US 10,446,584 B2
• Filed: 01/16/2019
• Issued: 10/15/2019
• Est. Priority Date: 09/13/2012
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei, Miyake, Hiroyuki, Shishido, Hideaki, Koyama, Jun
• Primary Examiner(s): Tran, Thien F
• Application Number:
  US16/248,978
• Publication Number:
  US 20190165003A1
• Time in Patent Office: 272 Days
• Field of Search: None
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 27/1255 integrated with passive devices, e.g. auxiliary capacitors
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

A semiconductor device including a capacitor whose charge capacity is increased while improving the aperture ratio is provided. Further, a semiconductor device which consumes less power is provided. A transistor which includes a light-transmitting semiconductor film, a capacitor in which a dielectric film is provided between a pair of electrodes, an insulating film which is provided over the light-transmitting semiconductor film, and a first light-transmitting conductive film which is provided over the insulating film are included. The capacitor includes the first light-transmitting conductive film which serves as one electrode, the insulating film which functions as a dielectric, and a second light-transmitting conductive film which faces the first light-transmitting conductive film with the insulating film positioned therebetween and functions as the other electrode. The second light-transmitting conductive film is formed over the same surface as the light-transmitting semiconductor film of the transistor and is a metal oxide film containing a dopant.

Claims

1. A display device comprising:

a first insulating film;

a first metal oxide film over the first insulating film;

a second metal oxide film over the first insulating film;

a gate electrode comprising a region overlapping with a channel formation region of the first metal oxide film;

a first conductive film over the first metal oxide film;

a second conductive film over the first metal oxide film;

a third conductive film over the second metal oxide film;

a second insulating film over the first to third conductive films and the first and second metal oxide films; and

a pixel electrode over the second insulating film,

wherein the first conductive film is electrically connected to the first metal oxide film,

wherein the second conductive film is electrically connected to the first metal oxide film,

wherein the third conductive film is electrically connected to the second metal oxide film,

wherein the pixel electrode is electrically connected to the first conductive film,

wherein the first and second metal oxide films comprise In, Ga and Zn,

wherein the second insulating film is an oxide insulating film,

wherein the second metal oxide film comprises a region having a higher conductivity than the channel formation region of the first metal oxide film, and

wherein the pixel electrode comprises a region overlapping with the second metal oxide film with the second insulating film interposed therebetween.

2. The display device according to claim 1, wherein the first to third conductive films have the same conductive material.

3. A display device comprising:

a first insulating film;

first to fourth metal oxide films over the first insulating film;

a first gate electrode comprising a region overlapping with the first metal oxide film;

a second gate electrode comprising a region overlapping with the third metal oxide film;

a first conductive film over the first metal oxide film;

a second conductive film over the first metal oxide film;

a third conductive film over the second and fourth metal oxide films;

a fourth conductive film over the third metal oxide film;

a fifth conductive film over the third metal oxide film;

a second insulating film over the first to fifth conductive films and first to fourth metal oxide films; and

first and second pixel electrodes over the second insulating film,

wherein the first conductive film is electrically connected to the first metal oxide film,

wherein the second conductive film is electrically connected to the first metal oxide film,

wherein the third conductive film is electrically connected to the second and fourth metal oxide films,

wherein the fourth conductive film is electrically connected to the third metal oxide film,

wherein the fifth conductive film is electrically connected to the third metal oxide film,

wherein the first pixel electrode is electrically connected to the first conductive film,

wherein the second pixel electrode is electrically connected to the fourth conductive film,

wherein the first to fourth metal oxide films comprise In, Ga and Zn,

wherein the second insulating film is an oxide insulating film,

wherein the second metal oxide film comprises a region having a higher conductivity than a channel formation region of the first metal oxide film,

wherein the fourth metal oxide film comprises a region having a higher conductivity than a channel formation region of the third metal oxide film,

wherein the first pixel electrode comprises a region overlapping with the second metal oxide film with the second insulating film interposed therebetween,

wherein the second pixel electrode comprises a region overlapping with the fourth metal oxide film with the second insulating film interposed therebetween, and

wherein the second conductive film is electrically connected to the fifth conductive film.

4. The display device according to claim 3, wherein the first to fifth conductive films have the same conductive material.