SUBMICRON AND LOW-TEMPERATURE OHMIC CONTACTS ON DELTA-DOPED GAAS

Practical nonalloyed ohmic contacts on delta-doped GaAs have been comp ared for AuGeNi (88:12:5)/and Cr metallizations to show the importance of metallization type for minimizing the contact resistance. They are shown to have low contact resistances even at 4.2 K and for contact s izes down to 240 nm diam. The effect of heating AuGeNi contacts to 270 degrees C is shown to be beneficial for large-area contacts but not f or submicron contacts, implying that nonuniformity is introduced. (C) 1996 American Institute of Physics.