| 摘要 |
PURPOSE:To obtain a microprism having a suffciently small inclination by forming an SiO2 film on a substrate 1 and forming pyramidal projections and recessions on the SiO2 film using an etching resist film having many windows provided by heat treating after implanting P ion into said film. CONSTITUTION:An SiO2 film 2 which is to form an etching film by thermal oxidation is formed on such as an Si substrate 1. The film 2 is implanted with P ion with 5X10<16>cm<-2> dose at 60KeV, the film is then heat-treated to result the distribution of the concentration of the doped P ion distributed in higher concentration toward the surface side. A photoresist film 3, for example, is then applied thereto; the film is exposed and developed to provide windows having a specified shape such as square pattern arranged longitudinally and laterally with a specified pitch. Recessions 5 are formed by etching the SiO2 film 2 with an HF etching liquid through the window 4 to obtain recessions 5 having <=7 deg. inclination theta. |
