| 摘要 |
PURPOSE:To improve the stability of wiring connection at the penetrated junction part of an insulation film by a method wherein an Si film is coated on a semiconductor substrate, and after the second region of the Si film is brought into the state of porosity leaving its first region as it is, the second region is formed into SiO2 by oxidizing the Si film. CONSTITUTION:An Si3N4 film 8 is coated on a semiconductor substrate 1 by performing a CVD (chemical vapor deposition) method, and an aperture 9 is formed on the surface of the substrate 1 using a photoetching technique. Then, P-type impurities such as a P-type boron-doped polycrystalline Si film 10, for example, is coated thereon by performing a CVD method. Subsequently, a resist mask 4 having a mask window 3 which is coincided with the aperture part 9, and the penetrated junction part of the P-type polycrystalline Si film 10 is turned to an N-type region 11 by ion-implanting N-type impurities such as arsenic, for example. Then, after the resist mask 4 is removed, the P-type region only of the polycrystalline Si film 10 is formed into a porous region 12 by applying a current into an HF solution. Then, a heat treatment is performed in the oxidizing atmosphere to approximately 1,000 deg.C, and the porous region 12 is oxidized and converted into an SiO2 region 13. As a result, the height of the surface of the SiO2 region 13 is almost coincided with the surface of the N-type region 11. Subsequently, a wiring 7 is formed by performing an ordinary method. |
