| 摘要 |
PURPOSE:To microscopically form the contact holes of a semiconductor device by a method wherein the contact holes are formed by utilizing the etching rate difference between the etching rate of a lower conductive material layer and that of a mask layer formed thereon. CONSTITUTION:An Si oxide layer 2, a conductive polycrystalline Si layer 3, an Si nitride layer 4 and a resist pattern 5 are provided in order on an Si substrate 1. After that, when an etching is performed on the nitride layer 4 and the polycrystalline Si layer 3 at the same time using the resist pattern 5 as a mask, the remaining partition of the nitride layer 4 is partitioned smaller than that of the polycrystalline Si layer 4. After the resist pattern 5 was stripped, resist films 5' are coated on positions of small partitions at the end parts of the Si layer 3, where are to become contact holes, and the nitride film 4 other than that located at the contact hole positions is removed. The resist films 5' are peeled off, a thermal oxidizing treatment is performed, and afterthe exposed surface part of the polycrystalline Si layer 3 was modified into an Si oxide, the nitride layer 4 is all stripped and the contact holes only of the polycrystalline Si layer 3 are exposed. After then, Al patterns 6 are formed by evaporation on the contact hole positions of the polycrystalline Si layer 3 and both wirings of the upper wiring and the lower wiring are connected to each other through the control holes. |
