Semiconductor integrated circuit and semiconductor substrate of the same

摘要

In a semiconductor integrated circuit, a P-type epitaxial layer is provided on the entire surface of a P-type bulk substrate. The resistivity of the P-type bulk substrate is set to 1000 Omega.cm, and the thickness and the resistivity of the P-type epitaxial layer is set to 5 mum and 10 Omega.cm, respectively. Then, a digital section and an analog section are provided remote from each other on the P-type epitaxial layer, where a digital circuit and an analog circuit are formed on the digital section and analog section, respectively. Further a device isolation region reaching the P-type bulk substrate is formed in a region between the digital section and analog section of the P-type epitaxial layer.