| 摘要 |
PURPOSE:To detect the final point of the removal of a film readily by visual observation, by providing a boundary detecting layer between a basic film and the film to be removed. CONSTITUTION:An SiO2 layer 2 and an Si3N4 layer 3 as a film are sequentially deposited on a semiconductor substrate 1. Holes are provided in these layers at element isolating regions, and U grooves 14 are formed. An SiO2 layer 15 is formed on the inner surface of each groove 14. Thereafter, an undoped poly Si layer 16 is deposited, and the inner part of each groove is filled. Then, the layer 16 on the layer 3 is removed. The layer 16 at the upper part in the groove 14 is further removed. Then, as a boundary detecting layer 4, an amorphous silicon layer 4 or an Al2O3 layer, whose refractive index is different from Si3N4 and SiO2, is deposited on the entire surface of the substrate. Thereafter, an SiO2 layer is deposited as the second film on the entire surface of the substrate 1. Then, the layer 5 deposited on the layer 3 is removed. In detecting the final point of the removal of the layer 5, exposure of the layer 4 is judged by visual observation. Thus the final point of the removal of the extra insulating body that is deposited on the substrate surface can be positively detected. |
