Microstructure and electrical property of tantalum oxynitride thin films prepared using high-power impulse reactive magnetron sputtering

摘要

Ta-N thin films were prepared on glass and Al2O3 substrates using high-power impulse reactive magnetron sputtering. A Ta target was used and sputtered using Ar/N-2 two gasses mixture. The phase structures, microstructures and electrical properties of Ta-N thin film with different powers and annealing temperatures were investigated. The results showed that an amorphous structure existed in the as-deposited Ta-N films at 500 W, and some crystalline phases (TaN, Ta2N and beta-Ta) were observed in as-deposited films at 1500 W and 2500 W. The crystallization phase did not change when the annealing temperature ranged from room temperature up to 500 degrees C. When the sputtering power increased to 2500 W, TaN, Ta2N and beta-Ta crystalline phases coexisted in the as-deposited films. However, Ta-N films deposited at 2500 W and annealed at 500 degrees C in N-2 exhibited resistivity of similar to 460 mu omega-cm with -93 ppm degrees C-1 temperature coefficient of resistance.