| 摘要 |
A semiconductor device, such as a p-HEMT or a quantum well laser, includes a semiconductor base substrate (101 or 121) having a lattice constant and a surface; and a strained layer (3 or 24) grown on the surface of the semiconductor base substrate and comprising a semiconductor having a zinc-blende crystal structure with a lattice constant different from that of the semiconductor base substrate. The interface between the semiconductor base substrate and the strained layer is in a crystal plane which satisfies the relationship of (1 - * small Greek nu * cos 2 * small Greek alpha *)/cos * small Greek lambda * > 2(1 - * small Greek nu */4), where * small Greek nu * is the Poisson ratio, * small Greek alpha * is the angle between the Burgers vector and the dislocation line, and * small Greek lambda * is the angle between the Burgers vector and the direction in the interface, normal to the dislocation line, and the strained layer is epitaxially grown on the surface of the semiconductor base substrate without generating lattice-mismatch dislocations. When a strained InGaAs layer grown as described above is employed as a channel layer of a p-HEMT, the In composition of this layer becomes larger than that of a channel layer grown on a (001)-oriented substrate, without generating dislocations, whereby the electron mobility in the channel layer is increased and the noise characteristics in high frequency bands are improved. Further, since the thickness of the channel layer becomes thicker than that of a channel layer grown on a (001)-oriented substrate, without generating dislocations, the sheet electron concentration is increased, whereby the high-output characteristics of the p-HEMT are improved.
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