| 摘要 |
PURPOSE:To prevent the generation of defective leakage generated through the implantation of impurity ions to the side surface of a U-shaped groove when forming a U-shaped groove isolation by selectively etching a SiO2 film on the bottom of the U-shaped groove and thinly forming the SiO2 film. CONSTITUTION:A U-shaped groove 2 is formed through selective etching while using a SiO2 film 6 shaped to a Si base body 1 as a mask. A SiO2 film 3 is formed to the inner surface of the groove 2. The film 3 is dry-etched to selectively etch only the film 3 on the bottom of the groove 2. A SiO2 film 3a on the side surface of the groove 2 is not etched at that time. B ions are implanted to introduce B to the base body 1 through a film 3b on the bottom of the groove 2. B is not introduced by the thick film 3a on the side surface of the groove 2 at that time. Accordingly, the generation of leakage along the side surface of the isolation groove 2 can be prevented. |
