Patent EP0493113A2 successfully refreshed from Google Patents.
EP0493113A2
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EP
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A method for producing a thin film transistor and an active matrix substrate for liquid crystal display devices
Assignee: Sharp Corp
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Filing: 1991-12-24
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Granted: —
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Expires: 2011-12-24
Abstract
Abstract A method for producing an active matrix substrate using a thin film transistor having a gate electrode (2) on an insulating substrate (1) covered with a gate insulating layer (3), a semiconductor layer (4) on the gate insulating layer, and a channel protective layer (5) on the semiconductor layer. After having patterned first the semiconductor layer (4) and the channel protective layer (5) together, and having subsequently patterned the channel protective layer (5), P⁺ ions are injected into the exposed semiconductor layer (4) forming the contact layers (6a,6b), using the left resist layer (11) as mask. Then a metal layer is deposed and patterned by use of a photomask thereby forming the source electrode (7) and the drain electrode (8), each having a portion overlying the gate electrode (2). Finally a transparent conductive layer is laminated on the whole surface and patterned by photolithography to form a pixel electrode (10). The method enhancing the transistor characteristics of the active matrix substrate with minimum leakage and the removal of an off-current generated from the presence of electrons and holes in the gate insulating layer.
Inventors
- 👤 Yasuhiro Mitani
- 👤 Katsumasa Ikubo
- 👤 Yasunori Shimada
- 👤 Hirohisa Tanaka
- 👤 Hiroshi Morimoto
- 👤 Yutaka Nishi
- 👤 Tomohiko Yamamoto
- 👤 Kenichi Nishimura
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 22:13
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/67; H10D30/6757; H10D30/01; H10D30/021; H10D30/031; H10D30/0312; H10D30/0314; H10D30/0316; H10D30/6704; H10D30/6713; H10D30/6729; H10D30/673; H10D30/6731; H10D30/6732; H10D30/674; H10D30/6741; H10D30/6743; H10D30/6745; H10D30/6746; H10D30/0321
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
134 words
A method for producing an active matrix substrate which uses a thin film transistor having a gate electrode on an insulating substrate covered with a gate insulating layer, a semiconductor layer on the gate insulating layer, a channel protective layer on the semiconductor layer, a drain electrode having a portion overlying the gate electrode with the interposition of the gate insulating layer, the semiconductor layer and the channel protective layer, and a source electrode having a portion overlying the gate electrode with the interposition of the gate insulating layer, the semiconductor layer and the channel protective layer, the method comprising the steps of patterning the channel protective layer, injecting ions into the semiconductor layer through a resist remaining after the patterning formation of the channel protective layer, so as to form a contact layer.
Claim 2
Dependent Claim
17 words
A method according to claim 1, wherein the contact layer is formed by patterning the semiconductor layer.
Claim 3
Dependent Claim
44 words
A method according to claim 1, wherein a resist is formed on the channel protective layer by patterning and ions are injected into the semiconductor layer through the resist, and the resist lifts off to form the drain electrode and source electrode in patterns.
Claim 4
Independent Claim
140 words
A method for producing an active matrix substrate which uses a thin film transistor having a gate electrode on an insulating substrate covered with a gate insulating layer, a semiconductor layer on the gate insulating layer, a drain electrode having a portion overlying the gate electrode with the interposition of the gate insulating layer and the semiconductor layer, and a source electrode having a portion overlying the gate electrode with the interposition of the gate insulating layer and the semiconductor layer, the method comprising the steps of patterning a resist on the semiconductor layer, injecting ions into the semiconductor layer through the resist, so as to form a contact layer, forming an electroconductive layer used for the drain electrode and source electrode without removing the resist, and lifting off the resist to form the drain electrode and source electrode separately.
Claim 5
Independent Claim
132 words
A method for producing an active matrix substrate which uses a thin film transistor having a gate electrode on an insulating substrate covered with a gate insulating layer, a semiconductor layer on the gate insulating layer, a channel protective layer on the semiconductor layer, a drain electrode having a portion overlying the gate electrode with the interposition of the gate insulating layer, the semiconductor layer and the channel protective layer, and a source electrode having a portion overlying the gate electrode with the interposition of the gate insulating layer, the semiconductor layer and the channel protective layer, the method comprising the steps of patterning the channel protective layer, injecting ions into the semiconductor layer by use of the patterned channel protective layer as a mask, so as to form a contact layer.
Claim 6
Dependent Claim
34 words
A method according to any of claim 1, 4 or 5, wherein the contact layer is formed by injecting ions at an accelerating voltage so that impurities do not reach the gate insulating layer.
Claim 7
Dependent Claim
31 words
A method according to any of claim 1, 4 or 5, wherein the ions are injected such that the contact layer has the same thickness as that of the semiconductor layer.
Claim 8
Independent Claim
163 words
A method for producing an active matrix substrate which uses a thin film transistor having a gate electrode on an insulating substrate covered with a gate insulating layer, a semiconductor layer on the gate insulating layer, a channel protective layer on the semiconductor layer, a drain electrode having a portion overlying the gate electrode with the interposition of the gate insulating layer, the semiconductor layer and the channel protective layer, and a source electrode having a portion overlying the gate electrode with the interposition of the gate insulating layer, the semiconductor layer and the channel protective layer, the method comprising the steps of forming the channel protective layer in a shape having reclining sides toward the source electrode and the drain electrode, and injecting ions into the semiconductor layer through the channel protective layer such that the contact layer is formed in the portions of the semiconductor layer which are directly below the foot of the reclining sides of the channel protective layer.
Claim 9
Independent Claim
167 words
A method for producing an active matrix substrate which uses a thin film transistor having a gate electrode on an insulating substrate covered with a gate insulating layer, a semiconductor layer on the gate insulating layer, a channel protective layer on the semiconductor layer, a drain electrode having a portion overlying the gate electrode with the interposition of the gate insulating layer, the semiconductor layer and the channel protective layer, and a source electrode having a portion overlying the gate electrode with the interposition of the gate insulating layer, the semiconductor layer and the channel protective layer, the method comprising the steps of forming the channel protective layer by patterning, and injecting ions diagonally from above with respect to the substrate into the semiconductor layer having an injected protective layer to form a contact layer in an area below the channel protective layer extending from the opposite ends of the semiconductor layer up to an area located inward of the opposite ends of the channel protective layer.
Claim 10
Independent Claim
182 words
A method for producing an active matrix substrate which uses a thin film transistor having a gate electrode on an insulating substrate covered with a gate insulating layer, a semiconductor layer on the gate insulating layer, a channel protective layer on the semiconductor layer, a drain electrode having a portion overlying the gate electrode with the interposition of the gate insulating layer, the semiconductor layer and the channel protective-layer, and a source electrode having a portion overlying the gate electrode with the interposition of the gate insulating layer, the semiconductor layer and the channel protective layer, wherein the semiconductor layer has a recess at the center in the direction of the width of the gate insulating layer, the channel protective layer has a narrower width than the semiconductor layer, and thinner crosswise portions than the central portion thereof, and ions are injected into the semiconductor through the channel protective layer such that a contact layer is formed in an area extending from the opposite ends of the semiconductor layer up to an area inside of the sides of the channel protective layer.
Claim 11
Independent Claim
201 words
A method for producing an active matrix substrate which uses a thin film transistor having a gate electrode on an insulating substrate covered with a gate insulating layer, a semiconductor layer on the gate insulating layer, a channel protective layer on the semiconductor layer, a drain electrode having a portion overlying the gate electrode with the interposition of the gate insulating layer, the semiconductor layer and the channel protective layer, and a source electrode having a portion overlying the gate electrode with the interposition of the gate insulating layer, the semiconductor layer and the channel protective layer, wherein the gate insulating layer has a central recess in the direction of width such that the gate insulating layer covers the gate electrode, the semiconductor layer having a stepped portion along the profile of the gate insulating layer, the channel protective layer having a narrower width than the semiconductor layer, and thinner crosswise portions than the central portion thereof, and ions are injected into the semiconductor through the channel protective layer such that a contact layer is formed in an area extending from the opposite ends of the semiconductor layer up to an area inside of the sides of the channel protective layer.
Claim 12
Independent Claim
171 words
A method for producing an active matrix substrate which uses a thin transistor layer having a semiconductor layer having a contact region and a channel region, a gate insulating layer, a gate electrode formed on a substrate in this sequence, a source electrode and a drain electrode each kept in contact with the contact region, the source electrode and the drain electrode partly overlapping with crosewise end portions of the semiconductor layer which are wider than the gate insulating layer and the gate electrode, wherein the crosswise sides of the gate insulating layer are declined wherein the side thereof toward the gate insulating electrode has a shorter reclining surface than that of the other side thereof toward the substrate, and ions are injected into the semiconductor layer from the gate electrode such that a contact layer is formed in a portion of the semiconductor layer overlapping with at least part of the reclining sides of the gate insulating electrode and part of the semiconductor layer out of the gate insulating layer.
Claim 13
Independent Claim
144 words
A method for producing an active matrix substrate which uses a thin transistor layer having a semiconductor layer having a contact region and a channel region, a gate insulating layer, a gate electrode formed on a substrate in this sequence, a source electrode and a drain electrode each kept in contact with the contact region, the source electrode and the drain electrode partly overlapping with crosswise end portions of the semiconductor layer which are wider than the gate insulating layer and the gate electrode, wherein the gate electrode is wider than the gate insulating layer, and ions are injected into the semiconductor layer from the gate electrode such that a contact layer is formed in an area extending from portions of the semiconductor layer which are located below the crosswise ends of the gate electrode up to the opposite sides of the semiconductor layer.
Claim 14
Dependent Claim
23 words
A method according to claim 1 or 5, wherein the resist is patterned by exposing the back of the gate electrode to light.
Claim 15
Dependent Claim
86 words
A method according to claim 1 or 5, wherein the resist is patterned by exposing the back of the gate electrode to light, and then the channel protective layer is patterned by use of the patterned resist, and ions are injected into the semiconductor layer through the channel protective layer to form a contact layer, and the contact layer is patterned by use of a second resist, wherein the second resist is used for patterning at least one of the source electrode and the drain electrode.
Claim 16
Dependent Claim
61 words
A method according to claim 1 or 5, wherein the resist used for fabricating the channel protective layer is patterned by exposing the back of the gate electrode to light, and then the channel protective layer is patterned by use of the patterned resist, and ions are injected into the semiconductor layer with the resist remaining to form a contact layer.
Claim 17
Independent Claim
58 words
A method for producing a thin-film transistor having a gate electrode, a semiconductor layer and an insulating layer between said gate electrode and said semiconductor layer, wherein said semiconductor layer is subjected to ion implantation to form respective contact layers for source and drain electrodes, characterised in that said semiconductor layer is patterned prior to the ion implantation.
References Cited (Backward Citations)
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