| 摘要 |
PURPOSE:To form grooves of different depth simultaneously through self-alignment by forming the grooves by using a mask pattern in which the opening width of the deep groove, the opening width of the shallow groove and the thickness of a buried layer are selected so as to satisfy predetermined relationship. CONSTITUTION:The n<+> type buried layer of thickness B, an n<-> epitaxial layer 33, SiO2 34 and a Si3N4 film 35 are formed onto a p type substrate 31. The deep grooves of opening width I1 and the shallow groove of opening width I2 are formed through etching. These grooves are formed so as to satisfy formula (I1-I2)Xtan54.7 deg./2>=B at that time. The grooves of different depth are etched until the deep grooves reach the buried layer through reactive etching. |
