| 摘要 |
A method of fabricating a bipolar transistor including emitter and base regions having first and second conductivity types, respectively, includes forming an isolation region at a surface of a semiconductor substrate, the isolation region having an edge that defines a boundary of an active area of the emitter region, and implanting dopant of the second conductivity type through a mask opening to form the base region in the semiconductor substrate. The mask opening spans the edge of the isolation region such that an extent to which the dopant passes through the isolation region varies laterally to establish a variable depth contour of the base region. |
