Characteristics of Ni/SiC Schottky diodes grown by ICP-CVD

摘要

A Ni/SiC Schottky diode was fabricated with an α-SiC thin film grown by the inductively coupled plasma chemical vapor deposition, ICP-CVD method on a (111) Si wafer. The α-SiC film was grown on a carbonized Si layer that the Si surface had been chemically converted to a very thin SiC layer by the ICP-CVD method at 700℃. To reduce defects between the Si and α-SiC, the surface of the Si wafer is slightly carbonized. The film characteristics of α-SiC were investigated by employing TEM and FT-IR. A sputtered Ni thin film was used for the anode metal. The boundary status of the Ni/SiC contact was investigated by AES as a function of annealing temperature. It is shown that the ohmic contact could be acquired below 1000℃ annealing temperature. The forward voltage drop of the Ni/α-SiC Schottky diode is 1.0 V at 100 A/cm~2. The breakdown voltage is 545 V which is five times larger than the ideal breakdown voltage of a silicon device. Also, the dependence of barrier height on temperature was observed.