Electrical properties and annealing effects on the stress of RF-sputtered c-BN films

The c-BN films prepared by RF sputtering were annealed immediately at tempe rature ranging from 773 to 1373 K in air and vacuum respectively. The therm al stability and the compressive film stress calculated from the frequency shift of cubic boron nitride (c-BN) infrared absorption peak were investiga ted. The results show that with increasing annealing temperatures the compr essive film stress decreases significantly, and the adhesion of c-BN film i s improved. The electrical measurements were performed for the annealed sam ples. The results show that the unintentionally doped c-BN films have n-typ e conductivity and the room temperature resistivity is in the range of 10(5 )-10(7) Omega cm, which is lower significantly than that of intrinsic bulk c-BN. The c-BN/p-Si heterojunction was fabricated and the I-V curve of this structure indicates typical semiconductor diode characteristics. (C) 2000 Elsevier Science B.V. All rights reserved.