| 摘要 |
PURPOSE:To provide a contact hole of predetermined diameter with good controlability by selectively forming an opening to a polycrystal silicon formed on a gate insulation film of substrate, etching a gate insulation film with such polycrystal silicon layer used as the mask and forming wirings covering the exposed region of etched semiconductor substrate and the upper part of gate insulation film. CONSTITUTION:A polycrystalline silicon layer 5 is provided between a photoresist layer 3 and an oxide film 2, the polycrystalline Si layer 5 is patterned by the dry etching and an oxide film 2 of the buried contact part is removed by the wet etching using such opening. In this case, damage by ion bombardment at the time of dry etching remains only on the oxide film 2 and is never generated at the surface of Si substrate 1 under such oxide film. Moreover, there is no chance of generating over-etching due to invasion of HF solution to the interface of such elements. Thereby, the buried contact can be formed between the polycrystal Si layer 4 and the Si substrate 1.
|
