Thin film transistor and method of fabricating the same
AssigneeLG Display Co., Ltd.
InventorsJae-Bum Park, Hyoung-Suk Jin
Life of this patent
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Abstract
A thin film transistor includes a substrate; a semiconductor layer disposed on the substrate, the semiconductor layer having a source region, a drain region, and a channel region between the source region and the drain region; a gate insulating layer disposed on the semiconductor layer and on the substrate; and a gate electrode disposed on the insulating layer over the channel region, wherein the semiconductor layer includes tapered edge portions with a taper angle defined between the tapered edge portions and a surface of the substrate is less than about 30 degrees.
Claims13
A method of manufacturing a thin film transistor, comprising:
- forming a silicon layer on a substrate;
- forming a photoresist layer on a portion of the silicon layer;
- performing a first etch process of the photoresist layer and the silicon layer using first reaction gases, wherein the etch rate of the photoresist is greater than that of the silicon layer in the first etch process, and wherein a portion within a range of about 70% to about 90% of the silicon layer is removed through the first etch process;
- performing a second etch process of the photoresist layer and the silicon layer using second reaction gases different from the first reaction gases, wherein the etch rate of the silicon layer is greater than that of the photoresist in the second etch process, and wherein the first and second etch processes form an active layer having an island shape with tapered edge portions and exposing adjacent portions of the substrate;
- removing the remaining photoresist layer remaining after the first and second etch processes;
- forming a gate insulating layer on the active layer and the substrate;
- forming a gate electrode on the gate insulating layer over the active layer;
- and
- implanting impurities into the active layer to define source and drain regions and to define a channel region under the gate electrode.
A method of fabricating an array substrate for a liquid crystal display device, comprising:
- forming a silicon layer on a substrate;
- forming a photoresist layer on a portion of the silicon layer;
- performing a first etch process of the photoresist layer and the silicon layer using first reaction gases, wherein the etch rate of the photoresist is greater than that of the silicon layer in the first etch process, and wherein a portion within a range of about 70% to about 90% of the silicon layer is removed through the first etch process;
- performing a second etch process of the photoresist layer and the silicon layer using second reaction gases different from the first reaction gases, wherein the etch rate of the silicon layer is greater than that of the photoresist in the second etch process, and wherein the first and second etch processes form an active layer having an island shape with tapered edge portions and exposing adjacent portions of the substrate;
- removing the remaining photoresist layer remaining after the first and second etch processes;
- forming a gate insulating layer on the active layer and the substrate;
- forming a gate line and gate electrode on the gate insulating layer, the gate electrode disposed over the active layer and connected to the gate line;
- implanting impurities into the active layer to define source and drain regions and to define a channel region under the gate electrode;
- forming an passivation layer on the gate electrode and the gate insulating layer;
- forming a data line, a source electrode and a drain electrode, the source electrode in contact with the source region via a first contact hole through the passivation layer;
- and
- forming an interlayer insulating layer on the data line, the source electrode and the drain electrode;
- and
- forming a pixel electrode on the interlayer insulating layer, the pixel electrode being connected to the drain electrode through the drain contact hole of the interlayer insulating layer.
Dependencies are inferred from the claim text.