Etching method, thin film transistor matrix substrate, and its manufacture
AssigneeFujitsu Limited
InventorYukimasa Ishida
Life of this patent
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Abstract
In a method of etching an Al or Al alloy layer, an Al or Al alloy layer is formed on an underlying surface, the surface of the Al or Al alloy layer is processed with TMAH, a resist pattern is formed on the surface of the Al or Al alloy layer processed with TMAH, and by using the resist pattern as an etching mask, the Al or Al alloy layer is wet-etched.
Claims28
A method of etching an Al or Al alloy layer, comprising the steps of:
- (a) forming an Al or Al alloy layer on an underlying surface;
- (b) processing a surface of the Al or Al alloy layer with tetramethylammonium hydroxide (TMAH);
- (c) forming a resist pattern on the surface of the Al or Al alloy layer processed with TMAH;
- and
- (d) wet-etching the Al or Al alloy layer, using the resist pattern as an etching mask.
A method of etching an Al or Al alloy layer, comprising the steps of:
- (a) forming an Al or Al alloy layer on an underlying surface;
- (b) slightly etching a natural oxide film or a natural hydrated film on a surface of the Al or Al alloy layer;
- (c) forming a resist pattern on the surface of the Al or Al alloy layer, after the step (b);
- and
- (d) wet-etching the Al or Al alloy layer, using the resist pattern as an etching mask.
An etching method comprising the steps of:
- (a) forming a metal layer on an underlying surface, the metal layer having a surface layer having a high etching rate;
- (b) processing a surface of the metal layer with TMAH;
- and
- (c) wet-etching the metal layer, using a resist pattern as an etching mask.
A thin film transistor matrix substrate comprising:
- an insulating substrate having a flat surface;
- a plurality of island patterns made of semiconductor and formed on the flat surface of said insulating substrate;
- a gate insulating film formed traversing a central area of a flat surface of each of the plurality of island patterns;
- and
- a gate layer formed on a central surface area of said gate insulating film and exposing a wing of said gate insulating film on both sides thereof, said gate layer having side walls of a forward taper slanted relative to a normal to the flat surface of said insulating substrate and an upper surface generally perpendicular to the normal, and serving as a gate electrode and a gate wiring pattern.
A method of manufacturing a thin film transistor matrix comprising the steps of:
- (a) forming a semiconductor layer on an insulating substrate;
- (b) forming a gate insulating film on the semiconductor layer;
- (c) forming a gate layer made of Al or Al alloy on the gate insulating film;
- (d) processing a surface of the gate layer with TMAH;
- (e) forming a resist pattern on the surface of the gate layer processed with TMAH;
- (f) wet-etching the gate layer, using the resist pattern as an etching mask, while the gate layer is formed with side walls of a forward taper;
- and
- (g) anisotropically dry-etching the gate insulating film by using the resist pattern as an etching mask.
A method of manufacturing a thin film transistor matrix comprising the steps of:
- (a) forming a semiconductor layer on an insulating substrate;
- (b) forming a gate insulating film on the semiconductor layer;
- (c) forming a first gate layer made of Al or Al alloy on the gate insulating film;
- (d) forming a second gate layer made of Ti on a surface of the first gate layer;
- (e) forming a resist pattern on a surface of the second gate layer;
- (f) wet-etching the first and second gate layers, using the resist pattern as an etching mask;
- and
- (g) anisotropically etching the gate insulating film by using the resist pattern as an etching mask.
Dependencies are inferred from the claim text.