Palladium Ohmic contact on hydrogen-terminated single crystal diamond film (Reprinted from Diamond and Related Materials, vol 59, pg 90-94, 2015)

Contact properties of Palladium (Pd) on the surface of hydrogen-terminated single crystal diamond were investigated with several treatment conditions. 150 nm Pd pad was deposited on diamond surface by thermal evaporation technique, which shows good Ohmic properties with the specific contact resistivity (pc) of 1.8 x 10(-6) Omega cm(2) evaluated by Transmission Line Model. To identify the thermal stability, the sample was annealed in Ar ambient from 300 to 700 degrees C for 3 min at each temperature. As the temperature increased, pc firstly decreased to 4.93 x 10(-7) Omega cm(2) at 400 degrees C and then increased. The barrier height was evaluated to be -0.15 eV and -0.03 eV for as-deposited and 700 degrees C annealed sample by X-ray photoelectron spectroscopy analysis. Several surface treatments were also carried out to determine their effect on p(c), among which HNO3 vapor treated sample indicates a lower value of 532 x 10-6 Omega cm(2). (C) 2015 Elsevier B.V. All rights reserved.