A semiconductor transistor device includes one or more conductive base regions, a first semiconductor barrier region, a second semiconductor barrier region, a conductive emitter region, and a conductive collector region. The first semiconductor barrier region or the second semiconductor barrier region has a dimension smaller than 100 Å. A first Schottky barrier junction is formed at the interface of the first semiconductor barrier region and the one or more conductive base regions. A second Schottky barrier junction is formed at the interface of the second semiconductor barrier region and the one or more conductive base regions. A third Schottky barrier junction is formed at the interface of the conductive emitter region and the first semiconductor barrier region. A fourth Schottky barrier junction is formed at the interface of the conductive collector region and the second semiconductor barrier region.