| 摘要 |
PURPOSE:To reduce a dislocation density in a compound semiconductor layer by a method wherein the thickness of a second compound semiconductor layer is set at a value within a specific range and the lattice constant of the second compound semiconductor layer is set at a range which satisfies a relational expression in which the lattice constant of a first compound semiconductor layer and the lattice constant of the second semiconductor layer are used as parameters. CONSTITUTION:A second compound semiconductor layer 3 is formed on a first compound semiconductor layer 2. The second compound semiconductor layer 3 is formed in a thickness of 400 to 1400Angstrom . In this case, the second compound semiconductor layer 3 is formed in such a way that its lattice constant becomes 3<=1 (a- b)/a1X10<3=10 [where (a) represents the lattice constant of the first compound semiconductor layer and (b) represents the lattice constant of the second compound semiconductor layer]. Then, a third compound semiconductor layer 4 is formed on the second compound semiconductor layer 3. |
