| 摘要 |
1353980 Semi-conductor devices PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd 3 Sept 1971 [8 Sept 1970] 41226/71 Heading H1K A low-resistance ohmic contact is formed on an N-type body of a III-V compound semiconductor such as GaAs, GaP or a mixture thereof by alloying with the body a doping layer comprising a metal such as Au, Ag, Sn or In, Ge which acts as a donor in the III-V compound and a further dopant, such as As, P or Sb, which acts as a donor in Ge. On recrystallization there are formed an N-type Ge-doped III-V layer and an overlying N-type Ge layer. After removal of the remaining part of the doping layer, e.g. using Hg or liquid Ga as a solvent, a metal contact is preferably applied to the N-type Ge layer to complete the ohmic contact. The metal contact may be of Au or Ag or of one of these metals on a layer of Cr, Al or Ti. Fig. 3 shows a plurality of mesa-like Gunn diodes 7 formed by etching a GaAs body mounted temporarily on a glass support 8. The GaAs body comprises an N<SP>+</SP>-type substrate 1 and an N-type epitaxial layer 2, both surfaces being provided with metal contacts 5, 6 in accordance with the invention. Other types of device to which the invention is applicable are avalanche diodes, varactor diodes, Schottky diodes and light-emissive diodes. |
