摘要 |
A semiconductor device ( 100 ) according to the present invention comprises a vertical PNP bipolar transistor ( 20 ), an NMOS transistor ( 50 ) and a PMOS transistor ( 60 ) that are of high dielectric strength, and a P-type semiconductor substrate 1 , as shown in FIG. 2 . A substrate isolation layer ( 21 ) of the PNP bipolar transistor ( 20 ), a drain buried layer ( 51 ) of the NMOS transistor ( 50 ), and a back gate buried layer ( 61 ) of the PMOS transistor ( 60 ) are formed simultaneously by selectively implanting N-type impurities, such as phosphorous, in the semiconductor substrate ( 1 ). This invention greatly contributes to curtailing the processes of fabricating BiCMOS ICs and the like including vertical bipolar transistors with easily controllable performance characteristics, such as a current amplification factor, and MOS transistors with high dielectric strength and makes even more miniaturization of such ICs achievable.
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