| 摘要 |
PURPOSE:To enable formation with a narrow and deep isolation width and with a small number of crystal defects by a method wherein an amorphous oxide film is grown on a thermal oxide film formed at the groove bottom of a single crystal Si substrate by the selective growing method, thus filling the groove. CONSTITUTION:A polycrystalline Si film 102 and an Si nitride film 103 are successively formed on the single crystal Si substrate 101. Next, grooves 104 and 105 for element isolation with different widths are formed, and thermal oxide films 106 are formed on the surfaces of the grooves 104 and 105. After removal of the film 103, a polycrystalline Si film 107 is formed. Then, the film 107 is etched only in the section of the film thickness. The amorphous Si oxide film 108 is formed on the film 106 at the groove bottom at a substrate temperature of 200 deg.C by the selective growing method. The element isolation region is formed by removing the part above the substrate 101. This element isolating method allows no growth of the film 108 on the surface of the film 107 on the groove side surface, but allows its growth on the film 106 at the groove bottom; therefore, grooves on the same substrate with the same depth inspite of different widths can be filled. Besides, the oxide film does not laterally grow because of low temperature growth. |
