# US 10,374,030 B2 · Metal oxide semiconductor device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,374,030 B2 - Document ID: US10374030B2 - Status: Granted - Kind: B2 - Application number: 15/687,061 - Filed: 2017-08-25 - Published: 2017-12-28 - Granted: 2019-08-06 - Earliest claimed: 2012-12-28 - Assignees: Semiconductor Energy Laboratory Co., Ltd. - Applicants: Semiconductor Energy Laboratory Co., Ltd. - Inventors: Shunpei Yamazaki; Masahiro Takahashi; Takuya Hirohashi; Masashi Tsubuku; Masashi Oota - Web page: https://patentgrep.com/patent/US10374030B2 ## CPC - H10D 62/40: Crystalline structures - H10D 30/6755: {Oxide semiconductors, e.g. zinc oxide, copper aluminium oxide or cadmium stannate} - H10D 30/6756: {Amorphous oxide semiconductors} - H10D 62/402: {Amorphous materials} - H10D 62/405: {Orientations of crystalline planes} - H10D 62/80: characterised by the materials - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES ## Abstract A highly reliable semiconductor device including an oxide semiconductor is provided. Provided is a semiconductor device including an oxide semiconductor layer, an insulating layer in contact with the oxide semiconductor layer, a gate electrode layer overlapping with the oxide semiconductor layer, and a source electrode layer and a drain electrode layer electrically connected to the oxide semiconductor layer. The oxide semiconductor layer includes a first region having a crystal whose size is less than or equal to 10 nm and a second region which overlaps with the insulating layer with the first region provided therebetween and which includes a crystal part whose c-axis is aligned in a direction parallel to a normal vector of the surface of the oxide semiconductor layer. ## Claims ### Claim 1 A semiconductor device comprising: a first silicon oxide film; a first oxide semiconductor film over the first silicon oxide film, the first oxide semiconductor film comprising a first metal element; and a second oxide semiconductor film over the first oxide semiconductor film, the second oxide semiconductor film comprising the first metal element, wherein the second oxide semiconductor film further comprises carbon or silicon as an impurity, and wherein an electron diffraction pattern by electron diffraction with a beam diameter of 1 nmφ of the second oxide semiconductor film has a plurality of circumferentially arranged spots. ### Claim 2 (depends on 1) The semiconductor device according to claim 1, wherein the first oxide semiconductor film has a different composition from the second oxide semiconductor film. ### Claim 3 (depends on 1) The semiconductor device according to claim 1, wherein each of the first oxide semiconductor film and the second oxide semiconductor film comprises indium, gallium and zinc, wherein a concentration of the second oxide semiconductor film is higher than a concentration of the first oxide semiconductor film. ### Claim 4 (depends on 1) The semiconductor device according to claim 1, wherein the second oxide semiconductor film comprises a first region and a second region, and wherein the first region has a different degree of crystallinity from the second region. ### Claim 5 (depends on 1) The semiconductor device according to claim 1, wherein the impurity is carbon. ### Claim 6 (depends on 1) A displayer device comprising the semiconductor device according to claim 1. ### Claim 7 (depends on 1) The semiconductor device according to claim 1, wherein the second oxide semiconductor film comprises indium, a second metal element and zinc, wherein the second metal element is one of Al, Ti, Ga, Y, Zr, La, Ce, Nd and Hf, wherein the first metal element is one of indium, the second metal element and zinc, and wherein a proportion of indium is greater than or equal to 25 atomic % and a proportion of the first metal element is less than 75 atomic % when zinc and oxygen are eliminated from consideration. ### Claim 8 (depends on 7) The semiconductor device according to claim 7, further comprising: a third oxide semiconductor film over the second oxide semiconductor film; and a second silicon oxide film over the third oxide semiconductor film, wherein the third oxide semiconductor film comprises one of indium, the second metal element and zinc. ### Claim 9 (depends on 1) The semiconductor device according to claim 1, wherein the first oxide semiconductor film has a different crystal structure from the second oxide semiconductor film. ### Claim 10 (depends on 9) The semiconductor device according to claim 9, wherein the second oxide semiconductor film comprises a first region including a crystalline part, and wherein an electron diffraction pattern by electron diffraction with a beam diameter of 1 nmφ of the second oxide semiconductor film has a plurality of spots which are arranged in an ordered manner. ### Claim 11 A semiconductor device comprising: a first silicon oxide film; a first oxide semiconductor film over the first silicon oxide film, the first oxide semiconductor film comprising a first metal element; and a second oxide semiconductor film over the first oxide semiconductor film, the second oxide semiconductor film comprising the first metal element, wherein the second oxide semiconductor film further comprises carbon or silicon as an impurity, wherein concentration of carbon or silicon is lower than or equal to 3×1018/cm3, and wherein an electron diffraction pattern by electron diffraction with a beam diameter of 1 nmφ of the second oxide semiconductor film has a plurality of circumferentially arranged spots. ### Claim 12 (depends on 11) The semiconductor device according to claim 11, wherein the first oxide semiconductor film has a different composition from the second oxide semiconductor film. ### Claim 13 (depends on 11) The semiconductor device according to claim 11, wherein the second oxide semiconductor film comprises a first region and a second region, and wherein the first region has a different degree of crystallinity from the second region. ### Claim 14 (depends on 11) The semiconductor device according to claim 11, wherein the impurity is carbon. ### Claim 15 (depends on 11) A displayer device comprising the semiconductor device according to claim 11. ### Claim 16 (depends on 11) The semiconductor device according to claim 11, wherein the first oxide semiconductor film has a different crystal structure from the second oxide semiconductor film. ### Claim 17 (depends on 16) The semiconductor device according to claim 16, wherein the second oxide semiconductor film comprises a first region including a crystalline part, and wherein an electron diffraction pattern by electron diffraction with a beam diameter of 1 nmφ of the second oxide semiconductor film has a plurality of spots which are arranged in an ordered manner. ### Claim 18 (depends on 11) The semiconductor device according to claim 11, wherein the second oxide semiconductor film comprises indium, a second metal element and zinc, wherein the second metal element is one of Al, Ti, Ga, Y, Zr, La, Ce, Nd and Hf, wherein the first metal element is one of indium, the second metal element and zinc, and wherein a proportion of indium is greater than or equal to 25 atomic % and a proportion of the first metal element is less than 75 atomic % when zinc and oxygen are eliminated from consideration. ### Claim 19 (depends on 18) The semiconductor device according to claim 18, further comprising: a third oxide semiconductor film over the second oxide semiconductor film; and a second silicon oxide film over the third oxide semiconductor film, wherein the third oxide semiconductor film comprises one of indium, the second metal element and zinc. ### Claim 20 (depends on 19) The semiconductor device according to claim 19, wherein the first oxide semiconductor film has a lower film density than the second oxide semiconductor film. ### Claim 21 A semiconductor device comprising: a first silicon oxide film; a first oxide semiconductor film over the first silicon oxide film, the first oxide semiconductor film comprising a first metal element; and a second oxide semiconductor film over the first oxide semiconductor film, the second oxide semiconductor film comprising the first metal element, wherein an electron diffraction pattern by electron diffraction with a beam diameter of 1 nmφ of the second oxide semiconductor film has a plurality of circumferentially arranged spots.