| 摘要 |
PURPOSE:To realize a THETA to be used as a semiconductor device by forming a first barrier layer, through which electrons can punch by a tunnel effect, and shaping a base electrode through a semiconducltor layer, which has impurity concentration higher than a base layer and is in contact with the upper surface of the base layer. CONSTITUTION:An N type GaAs layer 3 (a collector layer), an N type GaAs layer 5 (a base layer), an N type GaAs layer 7 (an emitter layer), non-doped AlGaAs layers 4 and 6 (barrier layers) and an N<+> type GaAs layer 8 are grown on an N<+> type GaAs substrate 1. Layers up to the AlGaAs barrier layer 6 from the N<+> type GaAs layer 8 are removed selectively to expose the N type GaAs base layer 5 in a region in which a base electrode is shaped. N<+> type GaAs layers 9 are grown selectively on the exposed surface of the N type GaAs base layer 5 by doping Sn. Sn is driven into the N type GaAs base layer 5 from the N<+> type GaAs layers 9 by using an external line flash lamp. Grooves 10 for element isolation are shaped, and a collector electrode 11, a base electrode 12 and an emitter electrode 13 are formed. |
