Focused ion beam assisted ohmic metallizations to p-6H-SiC

This work deals with the development of high temperature, low resistance ohmic metallizations to p-type 6H-SiC, using a novel approach of focused ion beam (FIB) surface-modification and in-situ direct-write metal deposition for ohmic contact formation without annealing. FIB(Ga) surface-modification and in-situ deposition of Pr, Mo and W showed minimum contact resistance values of 1.3 x10(-4) Ohm cm(2) to 7.3x10(-3) Ohm cm(2), depending on metal and FIB conditions. These contact resistance values of the direct FIB deposited non-annealed contacts, compare well with reported values for conventionally deposited and annealed contacts to SiC. Ex-situ E-beam deposition of Pt on FIB surface-modified and unmodified areas showed a substantial increase (one order of magnitude) in the contact resistance values of the unmodified contacts.