摘要 |
In a field effect transistor such as high output FET or low noise HEMT, a layer for facilitating re-combination of carriers (for example a superlattice buffer layer), an undoped compound semiconductor layer having a higher resistance than a channel layer and the channel layer made of a compound semiconductor are layered successively. In the layer for facilitating re-combination of carriers, for example, oxygen of high concentration is introduced, to facilitate the non-radiative recombination which shortens the life of injected carriers. The layer for facilitating re-combination of carriers is also formed by forming the superlattice layer at a lower temperature than the channel layer. Thus, efficiency and voltageproofness on high frequency, high output power operation is improved further, and noises can be decreased further on high frequency, low noise operation.
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