Semiconductor device

摘要

A semiconductor device and a manufacturing method for the same can be obtained wherein a semiconductor substrate of a high resistance that can enhance the Q value of a passive circuit element is used and leak current due to the impurity fluctuation that easily occurs in this high resistance semiconductor substrate, and whereby noise resistance of an active element in the high resistance semiconductor substrate is increased. A semiconductor device including a bipolar transistor formed in the main surface of a semiconductor substrate is provided wherein the bipolar transistor includes a semiconductor layer of a first conductive type at a bottom portion thereof and this semiconductor device is provided with a buried layer of a second conductive type, which is located in the semiconductor substrate so as to face the semiconductor layer of the first conductive type.