| 摘要 |
PURPOSE:To improve thermal resistance and reliability of an element by installing an ohmic electrode and a wiring which have thermal resistance on a compound semiconductor substrate. CONSTITUTION:On a semi-insulated GaAs substrate 4, an N type GaAs substrate 5 is selected, ions are injected and annealed. Next, a Ge film 6 which is patterned as a thin film semiconductor is formed. The film 6 is injected with As ions 7 which are N type impurity. Next, a W-Al film 8 which is high melting point metal is coated over the whole surface of the substrate 4 and is annealed. The above-mentioned process makes the film 6 high concentration N type and the film 6 ohmically contacts with the lower layer 5. Then, the film 8 is processed to a wiring pattern. In this way, the interface between the film 6 and the film 5 and the interface between the film 6 and the film 8 are rarely changed in quality or in surface since the ohmic contact is formed using solid state diffusion and the film 6 is covered with the film 8 and annealed. Further, As rarely evaporates from the film 6 and other GaAs surface due to the coverage by the film 8. |
