| 摘要 |
PURPOSE:To easily detect etching terminal for the formation of a concave part on the first material with good accuracy, by etching the third and first materials after the interposition of the second material with slow etching speed between the first and third materials with equal etching speed to provide the patterns of the second and third materials. CONSTITUTION:An SiO2 film 2, Si3N4 film 3 poly Si film 4 with the same thickness as a concave part provided on a substrate 1 are superposed on the Si substrate 1. A desired pattern is formed by successive etching with a resist mask 5. Next, the resist 5 is removed to simultaneously etch the poly Si film 4' and Si substrate 1 by a reactive sputter etching method. Continuous etching until the removal of the poly Si film 4' causes the formation of the concave part 6 with the same thickness as the film 4' on the Si substrate 1. The etching terminal is easily cleared on detecting the wave length of the luminous spectrum of an Si3N4 film 3' by spectroscopic method, etc. with the Si3N4 for an etching stopper. Thereafter, selective oxidation with the Si3N4 film 3' as a mask provides a field oxidized film 7 flat on the surface of the substrate. |
