| 摘要 |
PURPOSE:To obtain high-speed, high-performance ICs on the same substrate, by using an (n) well as a CMOS part, and using n<-> wells as a bipolar part. CONSTITUTION:n<+> layers 4 are embedded in a p-type substrate 1. A (p) epitaxial layer 2 is overlapped. Holes are provided with SiO2 as resist. P ions are implanted 3B in a BiP part (b) at a low concentration. After the surface is slightly oxidized, holes are provided in the new resist. P ions are implanted 3A into a pchMOS part of a CMOS part (a) at a high concentration. Then, thermal diffusion is performed, and n<-> layers and an (n) layer are made to reach the n<+> embedded layers. In this constitution, the CMOS formed in the (n) well can suppress a short channel effect due to fine machining. The high speed in a digital circuit can be implemented. In the bipolar part formed in the n<-> wells, the high breakdown strength of an n-p-n element and the current amplification factor of a p-n-p element can be improved. Therefore, analog and digital ICs characterized by the high speed and the high performances can be formed. |
