Method of manufacturing thin film transistors in a liquid crystal display apparatus

Claim 1

A method of manufacturing thin film transistors in a liquid crystal display apparatus, comprising the steps of: forming a gate electrode on a transparent insulating substrate; forming a gate insulator film on a region including said gate electrode and forming a pixel electrode transparent conductive film; growing a first semiconductor film which becomes a semiconductor active layer and a second semiconductor film larger energy band gap than said first semiconductor film on said gate insulator film; forming a photoresist pattern on the second semiconductor film and inside a position corresponding to a contour of said gate electrode; patterning to said first semiconductor film and said second semiconductor film using said photoresist pattern as a mask; forming a contact region by introducing impurities into an upper layer portion of said second semiconductor film after removing said photoresist pattern; forming a source electrode and a drain electrode connected to said contact region and separated thereon; and removing at least said contact region between said source electrode and said drain electrode by etching using said source electrode and said drain electrode as a mask.

Claim 2

A method of manufacturing thin film transistors in a liquid crystal display apparatus, comprising the steps of: forming a gate electrode on a transparent insulating substrate; forming a gate insulator film on a region including said gate electrode and forming a pixel electrode transparent conductive film; growing a first semiconductor film which becomes a semiconductor active layer and a second semiconductor film larger energy band gap than said first semiconductor film on said gate insulator film; forming a photoresist pattern on the second semiconductor film and inside a position corresponding to a contour of said gate electrode; patterning to said first semiconductor film and said second semiconductor film using said photoresist pattern as a mask; forming a contact region by introducing impurities into an upper layer portion of said second semiconductor film after removing said photoresist pattern; forming a source electrode and a drain electrode connected to said contact region and separated thereon; and removing at least said contact region between said source electrode and said drain electrode by etching using said source electrode and said drain electrode as a mask.

Claim 9

A method of manufacturing thin film transistors in a liquid crystal display apparatus, comprising the steps of: forming a gate electrode and a gate bus line conducting to said gate electrode on a transparent insulating substrate; forming a gate insulator film on a region including said gate electrode and said gate bus line; growing a first semiconductor film which becomes a semiconductor active layer and a second semiconductor layer larger energy band gap than said first semiconductor film on said gate insulator film; forming a photoresist pattern on the second semiconductor film and inside a position corresponding to a contour of said gate electrode; patterning to said first semiconductor film and said second semiconductor film using said photoresist pattern as a mask; forming a contact region by introducing impurities into an upper layer portion of said second semiconductor film after removing said photoresist pattern; forming a multilayer structure film composed of a pixel electrode transparent conductive film and a metal film on a region including said contact region and drain bus region, and a pixel region; forming a source electrode and a drain electrode connected to said contact region and separated thereon and a drain bus line connected to said drain electrode by applying patterning to said multilayer structure film, and leaving said multilayer structure film extending from said source electrode over to said pixel region; removing at least said contact region between said source electrode and said drain electrode by etching using said source electrode and said drain electrode as a mask; and removing said metal film existing in said pixel region.

Claim 10

A method of manufacturing thin film transistors in a liquid crystal display apparatus, comprising the steps of: forming a gate electrode and a gate bus line conducting to said gate electrode on a transparent insulating substrate; forming a gate insulator film on a region including said gate electrode and said gate bus line; growing a first semiconductor film which becomes a semiconductor active layer and a second semiconductor layer larger energy band gap than said first semiconductor film on said gate insulator film; forming a photoresist pattern on the second semiconductor film and inside a position corresponding to a contour of said gate electrode; patterning to said first semiconductor film and said second semiconductor film using said photoresist pattern as a mask; forming a contact region by introducing impurities into an upper layer portion of said second semiconductor film after removing said photoresist pattern; forming a multilayer structure film composed of a pixel electrode transparent conductive film and a metal film on a region including said contact region and drain bus region, and a pixel region; forming a source electrode and a drain electrode connected to said contact region and separated thereon and a drain bus line connected to said drain electrode by applying patterning to said multilayer structure film, and leaving said multilayer structure film extending from said source electrode over to said pixel region; removing at least said contact region between said source electrode and said drain electrode by etching using said source electrode and said drain electrode as a mask; and removing said metal film existing in said pixel region.