# US 2013/0153904 A1 · Semiconductor device and process for production thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0153904 A1 - Document ID: US20130153904A1 - Status: Published application - Kind: A1 - Application number: 13/819,352 - Filed: 2011-08-26 - Published: 2013-06-20 - Earliest claimed: 2010-08-30 - Assignees: Sharp Kabushiki Kaisha - Inventors: Jun Nishimura; Yukinobu Nakata; Yoshihito Hara - Web page: https://patentgrep.com/patent/US20130153904A1 ## CPC - H10D 84/00: Integrated devices formed in or on semiconductor substrates that comprise only semiconducting layers, e.g. on Si wafers or on GaAs-on-Si wafers - G02F 1/133345: {Insulating layers (G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence)} - G02F 1/136213: {Storage capacitors associated with the pixel electrode} - H10D 84/01: Manufacture or treatment - H10D 86/01: Manufacture or treatment - H10D 86/021: {of multiple TFTs} - H10D 86/0221: {comprising manufacture, treatment or patterning of TFT semiconductor bodies} - H10D 86/423: {comprising semiconductor materials not belonging to the Group IV, e.g. InGaZnO} - H10D 86/481: {integrated with passive devices, e.g. auxiliary capacitors} - H10D 86/60: wherein the TFTs are in active matrices - G02F 1/136227: {Through-hole connection of the pixel electrode to the active element through an insulation layer} - G02F 1/1368: in which the switching element is a three-electrode device {(G02F1/136277 takes precedence)} - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES - G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS ## Abstract A semiconductor device (1000) includes a thin film transistor having a gate line (3a), source and drain lines (13as, 13ad), and an island-like oxide semiconductor layer (7), and a capacitor element (105) having a first electrode (3b) formed from the same conductive film as the gate line (3s), a second electrode (13b) formed from the same conductive film as the source line (13as), and a dielectric layer positioned between the first electrode and the second electrode. A gate insulating film (5) has a layered structure including a first insulating layer (5A) containing an oxide and a second insulating layer (5B) disposed on the side closer to the gate electrode closer than the first insulating film and having a higher dielectric constant than the first insulating film, the layered structure being in contact with the oxide semiconductor layer (7). The dielectric layer includes the second insulating film (5B) but does not include the first insulating film (5A). Accordingly, the deterioration of the oxide semiconductor layer due to oxygen deficiency can be suppressed without reducing the capacitance value of the capacitor element). ## Claims ### Claim 1 A semiconductor device comprising a substrate, and a thin film transistor and a capacitor element disposed on the substrate, wherein the thin film transistor includes: an island-like oxide semiconductor layer having a channel region, and a first contact region and a second contact region positioned on respective sides of the channel region; a gate line disposed so as to overlap at least the channel region of the oxide semiconductor layer; a gate insulating layer formed between the gate line and the oxide semiconductor layer; a source line electrically connected to the first contact region; and a drain line electrically connected to the second contact region, the capacitor element includes: a first electrode formed from the same conductive film as the gate line; a second electrode formed from the same conductive film as the source line; and a dielectric layer positioned between the first and second electrodes, the gate insulating layer has a layered structure including a first insulating film containing an oxide which is in contact with the oxide semiconductor layer, and a second insulating film disposed on the side closer to the gate electrode than the first insulating film, the second insulating film having a dielectric constant higher than the first insulating film, and the dielectric layer includes the second insulating film, but does not include the first insulating film. ### Claim 2 (depends on 1) The semiconductor device of claim 1, wherein the first insulating film is positioned below the oxide semiconductor layer, and the first insulating film has substantially the same island-like pattern as that of the oxide semiconductor layer when viewed from the above of the substrate. ### Claim 3 (depends on 1) The semiconductor device of claim 1, wherein the gate line is disposed on the side of the substrate of the oxide semiconductor layer, and the semiconductor device further comprises an etch stop which covers at least the channel region of the oxide semiconductor layer. ### Claim 4 (depends on 3) The semiconductor device of claim 3, wherein an opening portion which reaches the second insulating film is formed in the etch stop and the first insulating film, and the second electrode is in contact with the second insulating film in the opening portion. ### Claim 5 (depends on 1) The semiconductor device of claim 1, further comprising a first interlayer insulating layer disposed on the thin film transistor and the capacitor element, and a second interlayer insulating layer disposed on the first interlayer insulating layer, wherein the first interlayer insulating layer has a layered structure including a lower film containing an oxide and an upper film disposed on the lower film. ### Claim 6 (depends on 5) The semiconductor device of claim 5, further comprising a conductive layer disposed on the second interlayer insulating layer, wherein the conductive layer is electrically connected to the first electrode or the second electrode of the capacitor element. ### Claim 7 (depends on 1) The semiconductor device of claim 1, wherein the thickness of the second insulating film is larger than the thickness of the first insulating film, and equal to or smaller than five times the thickness of the first insulating film. ### Claim 8 (depends on 1) The semiconductor device of claim 1, wherein the first insulating film is a silicon oxide film, and the second insulating film is a silicon nitride film. ### Claim 9 (depends on 1) A production method of the semiconductor device of claim 1, comprising the steps of: (A) forming a gate line and a first electrode of a capacitor element on a substrate; (B) depositing a second insulating film, a first insulating film, and an oxide semiconductor film, in this order, on the substrate on which the gate line and the first electrode are formed; (C) patterning the oxide semiconductor film, thereby obtaining an island-like oxide semiconductor layer; (D) removing a portion of the first insulating film positioned on the first electrode, thereby exposing the surface of the second insulating film; and (E) forming a metal film on the oxide semiconductor layer and on the exposed surface of the second insulating film, and patterning the metal film, thereby obtaining a source line, a drain line, and a second electrode of the capacitor element. ### Claim 10 (depends on 9) The production method of the semiconductor device of claim 9, wherein in the step (D), the first insulating film is etched by using the oxide semiconductor layer as a mask. ### Claim 11 (depends on 9) The production method of the semiconductor device of claim 9, further comprising, after the step (C), the steps of: (F1) forming an etch stop on the oxide semiconductor layer and the first insulating film; and (F2) patterning the etch stop, wherein the step (D) is performed simultaneously with the step (F2), and in the steps (D) and (F2), a portion of the etch stop positioned on a region which will be the first and second contact regions of the oxide semiconductor layer is removed, and a portion of the etch stop and the first insulating film positioned on the first electrode is removed, thereby exposing the second insulating film. ### Claim 12 (depends on 9) The method of the semiconductor device of claims 9, wherein the first insulating film is a silicon oxide film, and the second insulating film is a silicon nitride film.