Semiconductor device comprising a bipolar transistor and field-effect transistors.

摘要

A semiconductor device comprises a bipolar transistor (T1) having an emitter region (1) of one conductivity type formed in a base region (2) of the opposite conductivity type, the base region being provided in a collector region (3 and 4) of the one conductivity type. A first insulated gate field effect transistor (T2)provides a gateable connection to the emitter region (1) of the bipolar transistor (T1) while a second insulated gate field effect transistor (T3) provides a charge extraction path from the base region (2) when the bipolar transistor is turned off. The first insulated gate field effect transistor comprises a further region (6) of the other conductivity type provided in the emitter region. and a source region (9) of the one conductivity type formed in the further region(6) and an insulated gate (7) overlying a channel area comprising at least part of the further region (6) to provide a gateable connection between the emitter region (1) and the source region (9) of the first insulated gate field effect transistor (T2). The second insulated gate field effect transistor (T3) having an insulated gate (15) overlying a channel area comprising at least part of the emitter region (1) adjacent the base region (2) to provide a gateable connection between the base region (2) and a source of the second insulated gate field effect transistor.