MANUFACTURING METHOD FOR SEMICONDUCTOR DEVICE FIELD OXIDE

摘要

(a) The pad oxide film, the first nitride and the first nitride pattern(23) is formed in order on the silicon substrate(21). (b) The buffer polysilicon film, the second nitride is deposited on that substrate, then the photoresist pattern is formed. (c) The second nitride is etched by using the photoresist pattern the etching barrier, and the polysilicon is partly etched. (d) After the photoresist pattern is removed, the field oxide film(27) is formed. (e) The second nitride and the polysilicon film is removed. (f) The photoresist pattern is formed to remove Bird's beak which has been formed on the upper part of the first nitride, and then Bird's beak portion of the field oxide film is etched. (g) The photoresist pattern and the first nitride one is removed. Therefore, the active region of the element is increased, and also the topology of the substrate is relieved.