| 摘要 |
<p>A modulation doped base heterojunction bipolar transistor (10) wherein the base (16) is a modulation doped heterojunction formed of a layer (18) of p wide gap semiconductor material and a layer (20) of I narrow gap semiconductor material. The collector/base is formed with n+ narrow gap semiconductor material adjacent to the I region of the base. The emitter is n+ wide gap semiconductor material adjacent to the p wide gap layer of the base. The doping concentration and width of the p region of the base is such that all holes are depleted in that region, and a p type inversion layer (22) is formed in the I narrow gap material at its interface with the p wide gap material. This structure provides a modulation doped base heterojunction bipolar transistor which exhibits low base resistance, enhanced performance at low temperatures, a built-in drift field, a reduced emitter injection barrier, no minority carrier storage effects in the base region, and a built-in hot electron effect. <IMAGE></p> |
