| 摘要 |
PROBLEM TO BE SOLVED: To provide a low cost and good quality compound semiconductor wafer, compound semiconductor device, and compound semiconductor solar cell without using a thick-film GaAs buffer layer. SOLUTION: In a compound semiconductor wafer, a compound semiconductor device, and a compound semiconductor solar cell in which an epitaxial layer of compound semiconductor is formed on n-type Ge substrate 11, a low-cost and good quality compound semiconductor wafer, compound semiconductor device, and compound semiconductor solar cell can be provided by constituting the first layer of the epitaxial layer as n-type Alx Ga1-x As buffer layer 13 and setting AlAs mixed crystal ratio (x) within the range of 0.1 to 0.4 without using a thick GaAs buffer film, also the same effect can be reproduced in the case that the first layer of the epitaxial layer consists of n-type GaAs layer 12 of 0.02μm or less in thickness and the second layer of n-type Alx Ga1-x As buffer layer 13, and further the AlAs mixed crystal ratio (x) of the second layer is set within the range of 0.1 to 0.4. |
