Mitsubishi Denki Kabushiki Kaisha

Yoshikazu Yoneda

Akihiko Furukawa

Tatsuhiko Ikeda

Taisuke Furukawa

A semiconductor device and a method for manufacturing the device using a semiconductor substrate of a high resistance with improved Q value of a passive circuit element. Leakage current due to an impurity fluctuation, in the high resistance semiconductor substrate and noise resistance of an active element in the high resistance semiconductor substrate are improved. The semiconductor device includes a bipolar transistor at a main surface of and in the semiconductor substrate. The bipolar transistor includes a semiconductor layer of a first conductivity type at a bottom portion of the bipolar transistor and the semiconductor device includes a buried layer of a second conductivity type, located in the semiconductor substrate and facing the semiconductor layer of the first conductivity type.

Semiconductor device including bipolar transistor and buried conductive region

A semiconductor device includes a silicon semiconductor substrate, having a main surface including a first region and a second region side-by-side, an epitaxially grown layer of high resistivity as a first layer on the main surface, and an epitaxially grown layer of low resistivity as a second layer on the first layer, and having a resistivity lower than the resistivity of the first layer. The semiconductor device includes a bipolar transistor at the first region and a passive element at the second region. The second layer is covers at least the first region and is absent from at least a portion of the second region.

Semiconductor device

A method of manufacturing a semiconductor device is provided in which a semiconductor device including a plurality of FETs having different threshold voltages and gate insulating films with different film thicknesses can be manufactured in a simplified process. Specifically, a first gate insulating film is formed on the main surface of a semiconductor substrate. On the first gate insulating film, a first protection film is formed. In regions A and B in each of which an FET having a second gate insulating film with a film thickness different from that of the first gate insulating film is to be formed, the first gate insulating film and the first protection film are removed to expose the surface of the semiconductor substrate. At the same time, the first protection film is left in regions other than the regions A and B. Using the first protection film as a mask, an impurity is implanted into the semiconductor substrate in the regions A and B.

Growing community of inventors

Hyogo, Japan

Yoshikazu Yoneda