| 摘要 |
PURPOSE:To reduce the parasitic resistance of an ohmic contact by forming an ohmic contact electrode to be brought into contact with a germanium layer and shaping a germanium diffusion region reaching a two-dimensional electron gas from the germanium layer. CONSTITUTION:n<+> type Ge is grown on a non-doped i-type GaAs layer 2 and an n-type AlGaAs electron supply layer 3 in an epitaxial manner as a cap layer 6, an ohmic contact electrode 7 is disposed to be brought into contact with the layer 6, and a Ge diffusion region 7A reaching a two-dimensional electron gas 2e from the Ge cap layer 6 is formed. Accordingly, the Ge diffusion region 7A and the two-dimensional electron gas 2e are brought into contact positively, and the contact resistance of the ohmic contact electrode 7 and the n<+> type cap layer 6 and the sheet resistance of the n<+> type cap layer 6 are reduced. |
