| 摘要 |
PURPOSE:To obtain sufficient ohmic contact on a Ga1-xAlAs surface at 200 deg.C or more by composing electrode metals of Ni, Ge and Au. CONSTITUTION:An N type Ga1-xAlxAs 12 added with Te is formed by liquidus epitaxial on a semi-insulating substrate 11. In evaporating electrodes 13 on the layer 12, Au-Ge(12%)-Ni(4%) is used as a material and the substrate is maintained at 200 deg.C or more. In the temperature of 200 deg.C or more, a thin oxide film formed on the GaAlAs crystal surface is also destructed to adhere electrode metals to the crystal surface. Therefore, sufficient ohmic contact will be obtained. In this composition, a GaAs layer for connection is not required even if mixed crystal ratio of AlAs is 0.37 or more. The yield will be improved. |
