# US 9,437,594 B2 · Semiconductor device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,437,594 B2 - Document ID: US9437594B2 - Status: Granted - Kind: B2 - Application number: 13/947,724 - Filed: 2013-07-22 - Published: 2014-01-30 - Granted: 2016-09-06 - Earliest claimed: 2012-07-27 - Assignees: Semiconductor Energy Laboratory Co., Ltd. - Applicants: Semiconductor Energy Laboratory Co., Ltd. - Inventors: Shunpei Yamazaki; Tetsuhiro Tanaka; Yoshinori Ieda; Toshiyuki Miyamoto; Masafumi Nomura; Takashi Hamochi; Kenichi Okazaki; Mitsuhiro Ichijo; Toshiya Endo - Web page: https://patentgrep.com/patent/US9437594B2 ## CPC - H10D 87/00: Integrated devices comprising both bulk components and either SOI or SOS components on the same substrate - H10D 84/83: of only insulated-gate FETs [IGFET] - H10D 86/423: {comprising semiconductor materials not belonging to the Group IV, e.g. InGaZnO} - H10D 86/60: wherein the TFTs are in active matrices - H10D 88/00: Three-dimensional [3D] integrated devices - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES ## Abstract A nitride insulating film which prevents diffusion of hydrogen into an oxide semiconductor film in a transistor including an oxide semiconductor is provided. Further, a semiconductor device which has favorable electrical characteristics by using a transistor including a silicon semiconductor and a transistor including an oxide semiconductor is provided. Two nitride insulating films having different functions are provided between the transistor including a silicon semiconductor and the transistor including an oxide semiconductor. Specifically, a first nitride insulating film which contains hydrogen is provided over the transistor including a silicon semiconductor, and a second nitride insulating film which has a lower hydrogen content than the first nitride insulating film and functions as a barrier film against hydrogen is provided between the first nitride insulating film and the transistor including an oxide semiconductor. ## Claims ### Claim 1 A semiconductor device comprising: a first transistor comprising a silicon semiconductor film including a first channel formation region; an insulating film comprising a first nitride insulating film and a second nitride insulating film over the first transistor; a second transistor comprising an oxide semiconductor film including a second channel formation region over the insulating film; and a third nitride insulating film over the second transistor, wherein the second nitride insulating film is provided between the first nitride insulating film and the oxide semiconductor film, wherein a hydrogen concentration of the second nitride insulating film is lower than a hydrogen concentration of the first nitride insulating film, wherein an etching rate of the second nitride insulating film is less than or equal to 2.0 nm/minute under a condition where etching is performed at a temperature higher than or equal to 20° C. and lower than or equal to 25° C. with the use of 0.5 wt % of hydrofluoric acid, and wherein an etching rate of the third nitride insulating film is less than or equal to 2.0 nm/minute under a condition where etching is performed at a temperature higher than or equal to 20° C. and lower than or equal to 25° C. with the use of 0.5 wt % of hydrofluoric acid. ### Claim 2 (depends on 1) The semiconductor device according to claim 1, wherein a density of the second nitride insulating film is greater than or equal to 2.75 g/cm3. ### Claim 3 (depends on 1) The semiconductor device according to claim 1, wherein the hydrogen concentration of the first nitride insulating film is higher than or equal to 20 atomic % and lower than or equal to 25 atomic %. ### Claim 4 (depends on 1) The semiconductor device according to claim 1, wherein the hydrogen concentration of the second nitride insulating film is higher than or equal to 10 atomic % and lower than or equal to 15 atomic %. ### Claim 5 (depends on 1) The semiconductor device according to claim 1, wherein the second nitride insulating film is in contact with the first nitride insulating film. ### Claim 6 (depends on 1) The semiconductor device according to claim 1, wherein the first transistor and the second transistor each have a top-gate structure. ### Claim 7 (depends on 1) The semiconductor device according to claim 1, wherein the insulating film further comprises an oxide insulating film provided between and in contact with the first nitride insulating film and the second nitride insulating film. ### Claim 8 (depends on 1) The semiconductor device according to claim 1, wherein a density of the third nitride insulating film is greater than or equal to 2.75 g/cm3. ### Claim 9 (depends on 1) The semiconductor device according to claim 1, wherein a hydrogen concentration of the third nitride insulating film is higher than or equal to 10 atomic % and lower than or equal to 15 atomic %. ### Claim 10 (depends on 1) The semiconductor device according to claim 1, wherein the oxide semiconductor film comprises indium, gallium, and zinc. ### Claim 11 A semiconductor device comprising: a first transistor comprising a silicon semiconductor film including a first channel formation region; an insulating film over the first transistor, the insulating film comprising a first nitride insulating film, and a second nitride insulating film over the first nitride insulating film; a second transistor over the insulating film, the second transistor comprising a first electrode, a second electrode, and an oxide semiconductor film including a second channel formation region; and a third nitride insulating film over the second transistor, wherein each of the first electrode and the second electrode overlaps with the second channel formation region, wherein the first electrode is in contact with the second nitride insulating film, wherein a hydrogen concentration of the second nitride insulating film is lower than a hydrogen concentration of the first nitride insulating film, wherein an etching rate of the second nitride insulating film is less than or equal to 2.0 nm/minute under a condition where etching is performed at a temperature higher than or equal to 20° C. and lower than or equal to 25° C. with the use of 0.5 wt % of hydrofluoric acid, and wherein an etching rate of the third nitride insulating film is less than or equal to 2.0 nm/minute under a condition where etching is performed at a temperature higher than or equal to 20° C. and lower than or equal to 25° C. with the use of 0.5 wt % of hydrofluoric acid. ### Claim 12 (depends on 11) The semiconductor device according to claim 11, wherein a density of the second nitride insulating film is greater than or equal to 2.75 g/cm3. ### Claim 13 (depends on 11) The semiconductor device according to claim 11, wherein the hydrogen concentration of the second nitride insulating film is higher than or equal to 10 atomic % and lower than or equal to 15 atomic %. ### Claim 14 (depends on 11) The semiconductor device according to claim 11, wherein the oxide semiconductor film comprises indium, gallium, and zinc. ### Claim 15 A semiconductor device comprising: a first transistor comprising a silicon semiconductor film including a first channel formation region; an insulating film over the first transistor, the insulating film comprising a first nitride insulating film, and a second nitride insulating film over and in contact with the first nitride insulating film; a second transistor over the insulating film, the second transistor comprising a first electrode, a second electrode, and an oxide semiconductor film including a second channel formation region; and a third nitride insulating film over the second transistor, wherein each of the first electrode and the second electrode overlaps with the second channel formation region, wherein the first electrode is in contact with the first nitride insulating film, wherein a hydrogen concentration of the second nitride insulating film is lower than a hydrogen concentration of the first nitride insulating film, wherein an etching rate of the second nitride insulating film is less than or equal to 2.0 nm/minute under a condition where etching is performed at a temperature higher than or equal to 20° C. and lower than or equal to 25° C. with the use of 0.5 wt % of hydrofluoric acid, and wherein an etching rate of the third nitride insulating film is less than or equal to 2.0 nm/minute under a condition where etching is performed at a temperature higher than or equal to 20° C. and lower than or equal to 25° C. with the use of 0.5 wt % of hydrofluoric acid. ### Claim 16 (depends on 15) The semiconductor device according to claim 15, wherein a density of the second nitride insulating film is greater than or equal to 2.75 g/cm3. ### Claim 17 (depends on 15) The semiconductor device according to claim 15, wherein the hydrogen concentration of the second nitride insulating film is higher than or equal to 10 atomic % and lower than or equal to 15 atomic %.