| 摘要 |
<p>PURPOSE:To prevent between a gate electrode and a source electrode or a drain electrode from being short-circuited in an etching step by forming a gate insulating film in a laminated structure of a lower layer insulating film made of an insulating material not dissolved by a fluoric acid solution and an upper layer insulating film made of a silicon compound. CONSTITUTION:A gate insulating film is formed of two layers, first layer (lower layer) 31 of which is made of an insulating film not dissolved in an HF solution, and the second layer 32 of the upper layer is made of a material which can obtain preferable characteristics of a thin film transistor, such as an SiO2 normally used in a laminated structure. Accordingly, in the surface treatment of an operating semiconductor layer 4 prior to the formation of a source electrode 5 and a drain electrode 5', even if pinholes exist in the layer 4 and the film 32 is etched by an HF etchant to form a through hole, the film 31 is not etched, and the formation of the through hole is stopped here. Thus, even if a conductive material is filled in the through hole formed in the film 32, a gate electrode 2 is not short-circuited.</p> |
