| 摘要 |
<p>PURPOSE: To prevent a bird's peak from being generated and reduce an element separation region to submicron which is the limit of the lithography technique, without using a thermal oxidation method by forming an element separation film utilizing the CVD process and the lithography technique. CONSTITUTION: A mutlilayer film is formed by the normal CVD, and the specific part of an oxide film 9 and a nitride film 7 is eliminated by the normal lithography technique and an element separation region is limited to a submicron level. A polycrystalline silicon film 5 on an exposed element separation region is thermally oxidized by a specific thickness, a formed cap oxide film 13 is utilized as a mask, and the nitride film 7 is eliminated by the wet etching method. An oxide film 3 on the element separation region and a gap oxide film 13 on the element region are eliminated by the RIE method. However, a part on the element separation region in the oxide film 3 cannot be etched by the polycrystalline silicon film 5 and becomes an element separation film 15. At that time, since no thermal oxidation methods are used, no transfer due to a bird's peak or stress occur, and no impurity of an ion implantation region 11 are diffused.</p> |
