Method of fabricating thin film semiconductor integrated circuit

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

• forming a first semiconductor region on an insulating substrate in a pixel region;
• forming a second semiconductor region on the insulating substrate in a peripheral circuit region;
• forming an insulating film on the first and second semiconductor regions;
• forming gate electrodes on the first and second semiconductor regions respectively through the insulating film;
• forming a porous anodic oxide on at least both sides of the gate electrode provided only on the first semiconductor region;
• forming barrier anodic oxides on at least both sides of the gate electrodes provided on the first and second semiconductor regions;
• introducing impurity into the first and second semiconductor regions using the gate electrodes and the porous anodic oxide and the barrier anodic oxides as masks, to form offset regions in the first and second semiconductor regions of different widths between the first semiconductor region and the second semiconductor region,
• wherein the offset regions formed in the first semiconductor region have the same width on both sides, and the offset regions formed in the second semiconductor region have the same width on both sides.

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

• forming first and second semiconductor regions on an insulating surface;
• forming an insulating film on the semiconductor regions
• forming gate electrodes on the semiconductor regions respectively through the insulating film;
• forming porous anodic oxides having different thicknesses on both sides of the gate electrodes provided on the first and second semiconductor regions;
• and
• forming a barrier anodic oxide on at least the both sides of the gate electrode provided on only the second semiconductor region;
• etching a portion of the insulating film using the porous anodic oxides and the barrier anodic oxide and the gate electrodes as masks to pattern the insulating film into two islands;
• removing the porous anodic oxides by etching;
• and
• introducing impurity into the first and second semiconductor regions using the gate electrodes and the two islands and the barrier anodic oxide as masks, to form lightly doped regions in the first and second semiconductor regions of different widths between the first semiconductor region and the second semiconductor region, and to form an offset region in only the second semiconductor region.