| 摘要 |
PURPOSE:To prevent latch-up phenomenon, and to obtain the titled device increased in density of elements, by a method wherein a semiconductor substrate is provided with element isolation grooves filled with a mixture made of specific substance. CONSTITUTION:An element isolation groove is formed at the boundary between the n-type semiconductor substrate 1 and a p-well 2. This groove is filled with the mixture 71 of polycrystalline Si with polycrystalline Ge. An oxide film 6 is formed among the mixture 71, substrate 1, and well 2. Besides, an oxide film 8 is formed on the upper surface of the mixture 71. There are p<+> regions 9 and n<+> regions 10 on both adjacent sides of the groove. This element isolation groove isolates the substrate 1 from the well 2 and electrically insulates the p<+> regions 9 in the substrate 1 from the n<+> regions 10 on the well 2; thereby, the latch-up phenomenon generating in the titled device of CMOS structure can be prevented. Besides, the increase in density of elements can be contrived by reducing the width of the element isolation groove. |
