| 摘要 |
1375269 Semi-conductor devices RCA CORPORATION 9 June 1972 [18 June 1971] 27194/72 Heading H1K A semi-conductor structure is formed with an epitaxial layer having its free surface smooth and flat by depositing the epitaxial layer by liquid phase epitaxy, depositing on the epitaxial layer an additional layer of semiconductor material, also by liquid phase epitaxy, and removing all the additional layer with an etchant which does not etch the epitaxiallayer. A light emitting diode may be produced having an N-type gallium arsenide substrate and two P-type epitaxial layers formed from the liquid phase, the upper epitaxial layer being of GaAs. The additional layer may be of Ga 1-x Al x As where x >0�3, and this layer may be etched with hydrochloric acid, which does not attack GaAs or Ga 1-x Al x As where x <0�3, which forms the lower epitaxial layer. The surface of the epitaxial layer exposed by etching is particularly suitable for contact with a heat sink. P-conductivity type may be achieved using a zinc dopant in the liquid phase. As an alternative, the upper epitaxial layer may be of Ga 1-x Al x As where x <0�3. |
