| 摘要 |
PURPOSE:To implement low contact resistance between a two-dimensional gas channel (2DEG) layer and ohmic alloy layers, by directly contacting the 2DEG layer and a low resistance semiconductor layer. CONSTITUTION:This HEMT is composed of the following parts: a mesa part, which comprises a GaAs layer 1 and an n-AlGaAs layer 2 that undergo mesa etching in a trapezoidal shape; a low resistance semiconductor layer 20 comprising n<+> GaAs and the like; ohmic alloy layers 11 and 12; two-dimensional gas channel layer (2DEG layer) 6; and a gate electrode 13. At least a part of the 2DEG layer 6 is exposed to the side wall of the mesa part. The low resistance semiconductor layer 20 is directly contacted with the exposed part of the 2DEG layer 6. The layer 20 is located between the ohmic alloy layers 11 and 12, which are to become source and drain electrodes, and the 2DEG layer. Since the low resistance semiconductor layer is provided between the ohmic electrodes, which are to become the source and the drain, and the two-dimensional gas channel layer, the low contact resistance can be implemented with good reproducibility. |
