| 摘要 |
PURPOSE:To enlarge a surface area of a silicon film with excellent reproducibility by a method wherein an oxide film having an uneven thickness is formed on a silicon, and a part of the oxide film is reduced with gas containing a metal element and reacts on the exposure surface of a silicon to grow a metal film to remove it. CONSTITUTION:By using mixed liquid of H2O2 water with sulfuric acid, an oxide silicon film 13 having an uneven thickness is formed on the surface of a polycrystalline silicon film 12. Next, a substrate 11 is placed within WF6 gas diluted with Ar gas. Thus, a comparatively thin part of the oxide silicon film 13 is completely reduced and removed, and reacts on the surface of the polycrystalline silicon film 12 to grow unevenly tungsten on the polycrystalline silicon film 12. Next, the grown tungsten film 14 is removed by wet-etching. Thus, the surface area of the polycrystalline silicon 12 can be enlarged 1.2 to 1.6 times as large as before. |
