| 摘要 |
PURPOSE:To prevent abnormal exposure due to reflection by a base layer and to improve dimensional conversion difference and pattern shape in the process of forming a three-layers resist on the base layer having high reflectance. CONSTITUTION:A lower resist layer 4 formed on a base material layer 3 having high reflectance and steps is patterned by etching with fast high-anisotropic ion-mode etching method with using a SiON intermediate layer pattern 5a formed by plasma CVD method as a substantial mask. Thereby, the SiON intermediate layer 5 formed by plasma CVD method acts as an excellent antireflection film for exposure light of short wavelengths. Thus, an upper layer resist pattern 6 can be formed with high controllability. The intermediate layer is dense and excellent in ion shock resistance so that decrease in the film thickness or sinking of the pattern 5a are prevented and that the pattern 4a of the lower resist layer is made accurate for the design rule. By forming the intermediate layer 5 by low temp. plasma CVD method, no thermal damage is given to the lower resist layer. |
