| 摘要 |
PURPOSE:To obtain a miniaturized element isolation region without intruding into element forming region by forming a recessed region through etching to the Si substrate with a thick resist pattern used as the mask and forming SiO2 film to such recessed region by the CVD method. CONSTITUTION:A Si substrate 1 is coated with a thick resist film 4a, it is then patterned, and a recessed region 7 is formed by executing the etching to the Si substrate 1 with such resist film 4a used as the mask. In succession, the boron ion is implanted to the bottom part of recessed region 7. Next, the SiO2 film 8 is deposited on the entire part by the plasma CVD method or photo CVD method. Thereafter, etching is carried out for a short period of time using fluoric acid, the SiO2 film adhered to the internal wall of window on the resist film 4a is removed in order to isolate the SiO2 film 8a in the recessed region 7 and the SiO2 film 8b on the resist film 4a. Finally, the resist film 4a is removed together with the SiO2 film 8b formed thereon and the SiO2 film 8a is left in the recessed region 7. As explained above, a miniaturized element isolation oxide film having no bird beak can be obtained. |
