Dear all,
          i am having a problem getting a good ohmic contact on n-GaAs. As
suggested in theory, i have used Au-Ge( 88%:12%) and evaporated them
together in a Tungsten boat in a vacuum coating unit. but i am still getting
schottky diode like characteristics of the contact. i have also annealed the
sample after metallization at temperatures like 360-400 degrees C (not RTA)
for 1-2 mins but still am not getting good ohmic contact. is there any
specific thing i should follow while evaporation? kindly suggest me any
solutions.
   thank you

sachin narwade
MEMS and  microelctronics lab
IIT Madras, Chennai,
India.