| 摘要 |
PURPOSE:To form an ohmic electrode of cBN which is linear in current-voltage characteristics a method wherein platinum is evaporated on a P-type cubic boron nitride(cBN) at a normal temperature, and molybdenum is evaporated on an N-type cBN at a normal temperature. CONSTITUTION:Platinum is evaporated on P-type cBN, and molybdenum is evaporated on N-type cBN for the formation of ohmic electrodes. A two- electrode direct current sputtering method is used in an evaporation process. A specimen of cBN is fixed onto an anode with insulating varnish. Varnish is applied crosswise onto the surface of a crystal. A disc of electrode material metal to evaporate is placed on a cathode. All the assembly concerned is installed in a vacuum chamber, argon gas of ultrahigh purity is introduced into the chamber, and a voltage is applied between the anode and the cathode to execute an evaporation process. Then, electrode metal material is brought into ohmic contact with a cBN semiconductor by high-temperature annealing. By this setup, an ohmic electrode is formed, and a cBN semiconductor device linear in current-voltage characteristics can be obtained. |
