| 摘要 |
<p>PURPOSE:To detect the etching termination with high precision for avoiding the deterioration in TFT characteristics by a method wherein the difference in the conductivity of an amorphous silicon active layer and an N<+> type amorphous silicon layer is used to electrolytically etch away the N<+> type amorphous silicon layer. CONSTITUTION:Within the title manufacture of liquid crystal display unit, an amorphous silicon active layer 10 is exposed by electrolytically etching away an amorphous silicon contact layer 11 corresponding to the channel of a TFT. This N<-> type amorphous silicon film 11 in high conductivity can be rapidly etched away. However, when the amorphous silicon film 11 is completely etched away, the current starts to run into the amorphous silicon film 10 in low conductivity for rapidly decelerating the etching rate as well as rapidly decreasing the current running between cathode and anode. By detecting this decrease in current, the etching termination can be detected thereby enabling the excessive etching step of the amorphous silicon film 10 to be avoided.</p> |
