| 摘要 |
PURPOSE:To obtain precise and fine separating space, in the case a polycrystalline Si film used for wiring layers and the like are formed on a semiconductor substrate and the film is separated by the fine separating space, by performing etching using a metal mask having a steep step depending on the fine separating space. CONSTITUTION:The polycrystalline layer 2 to be etched used for the wiring layers and the like is deposited on the semiconductor substrate 1. An SiO2 film 3 is formed so that the film reaches the position where the fine separating space is to be provided. Then, an Al film 6 is evaporated on all the surface in a vacuum, a step 5 is provided at the end surface of the film 3. The Al film 6a at the stepped part is roughened at a lower density. The etching speed in this place is several times- several tens times faster than the speed at the other part of the film 6. Then, the product is immersed in the etchant whose main components are phosphoric acid and nitric acid, the Al film 6a is removed, thereby an Al film pattern 7 with fine separating space is obtained. With this as a mask, the Si film 2 which is the groundwork is etched, and divided by the separation of 0.5-1.0mum. The unnecessary pattern is removed. |
