Liquid crystal display and method

A method of fabricating a semiconductor device, comprising the steps of:

• forming a semiconductor layer on a surface of a substrate;
• forming a first conductive layer on said semiconductor layer;
• forming a passivation layer on said first conductive layer;
• patterning said passivation layer to provide first and second openings in said passivation layer to expose first and second portions, respectively, of said first conductive layer;
• forming a second conductive layer on said passivation layer and extending through said first opening to contact said first conductive layer;
• and
• etching said second portion of said first conductive layer and a portion of said semiconductor layer underlying said second portion of said conductive layer in a single processing step using said patterned passivation layer as a mask.

A method of manufacturing an active matrix liquid crystal display, comprising the steps of:

• depositing a first metal layer on a substrate;
• patterning said first metal layer to form a gate electrode;
• depositing a gate insulating layer on said substrate and said gate electrode;
• depositing a first semiconductor layer on said gate insulating layer;
• depositing an etch resistant layer on said first semiconductor layer;
• patterning said etch resistant layer to form an etch stop portion;
• depositing a second, impurity containing, semiconductor layer on said etch stop portion and said first semiconductor layer;
• depositing a second metal layer on said impurity containing layer;
• patterning said second metal layer;
• said second impurity containing semiconductor layer and said first semiconductor layer in a single step;
• depositing a passivation layer on said patterned second metal layer and said gate insulating layer;
• patterning said passivation layer to form an opening over said etch stop portion and a contact hole over part of said patterned second metal layer;
• depositing a transparent conductive layer on said patterned passivation layer and in said contact hole;
• patterning said transparent conductive layer to form a pixel electrode electrically connected to said part of said patterned second metal layer;
• and
• etching said second metal layer and said second impurity containing semiconductor layer in a single processing step using said patterned passivation layer as a mask to thereby form source and drain electrodes.

A method for manufacturing a semiconductor device comprising the steps of:

• depositing a first semiconductor layer on a substrate;
• depositing a second semiconductor layer on said first semiconductor layer;
• depositing a conductive layer on said second semiconductor layer;
• depositing a passivation layer on said conductive layer;
• patterning said passivation layer to provide a plurality of openings exposing said conductive layer;
• and
• etching portions of said conductive layer and said second semiconductor layer in a single processing step using said patterned passivation layer as a mask, whereby an etch stop portion is exposed through one of the plurality of openings.