US 11,843,004 B2
Semiconductor device having specified relative material concentration between In—Ga—Zn—O films
Shunpei Yamazaki, Setagaya (JP); Junichi Koezuka, Tochigi (JP); Yasutaka Nakazawa, Tochigi (JP); Yukinori Shima, Tatebayashi (JP); Masami Jintyou, Shimotsuga (JP); Masayuki Sakakura, Isehara (JP); and Motoki Nakashima, Atsugi (JP)
Assigned to Semiconductor Energy Laboratory Co., Ltd., Kanagawa-ken (JP)
Filed by Semiconductor Energy Laboratory Co., Ltd., Atsugi (JP)
Filed on Jul. 8, 2021, as Appl. No. 17/370,075.
Application 17/370,075 is a continuation of application No. 16/420,858, filed on May 23, 2019, granted, now 11,063,066.
Application 16/420,858 is a continuation of application No. 14/247,676, filed on Apr. 8, 2014, granted, now 10,304,859, issued on May 28, 2019.
Claims priority of application No. 2013-084074 (JP), filed on Apr. 12, 2013.
Prior Publication US 2021/0343754 A1, Nov. 4, 2021
Int. Cl. H01L 27/12 (2006.01); H01L 29/786 (2006.01); H01L 29/66 (2006.01); H01L 29/04 (2006.01); H01L 21/02 (2006.01)
CPC H01L 27/1225 (2013.01) [H01L 29/66969 (2013.01); H01L 29/7869 (2013.01); H01L 29/78696 (2013.01); H01L 21/02609 (2013.01); H01L 27/1229 (2013.01); H01L 29/04 (2013.01); H01L 29/045 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A semiconductor device comprising:
a gate electrode;
a gate insulating film over the gate electrode;
a first In—Ga—Zn oxide film over the gate insulating film;
a second In—Ga—Zn oxide film over the first In—Ga—Zn oxide film; and
a pair of electrodes over the second In—Ga—Zn oxide film, the pair of electrodes comprising copper,
wherein the first In—Ga—Zn oxide film contains In, Ga, and Zn at an atomic ratio of x2:y2:z2,
wherein the second In—Ga—Zn oxide film contains In, Ga, and Zn at an atomic ratio of x1:y1:z1,
wherein y1/x1 is three or more times as high as y2/x2, and
wherein the second In—Ga—Zn oxide film has a non-single crystal structure and comprises c-axis aligned crystals.