Synthesis of tantalum nitride coatings with stable sheet-resistance by RF reactive magnetron sputtering

The TaN coatings with stable sheet-resistance were deposited by RF magnetron sputtering on alumina substrate in a lab-built reactor. The influence of the growth conditions, including the N2-partial pressure in N2 + Ar mixture, substrate temperature and deposition time, on the microstructures and sheet-resistance of the TaN coatings was investigated with X-ray diffraction and four-probe resistivity measurement. The results show that the N2-partial pressure, substrate temperature and deposition time strongly affect the growth and sheet-resistance of the TaN coatings. For example, as the N2 partial pressure increased from 4% to 6% and 8%, bcc-TaN0.04, fcc-TaN1.13 and amorphous TaN were observed, respectively; and the sheet-resistance rapidly increased. The sheet-resistance decreased to below 100 Ω/ when the substrate temperature rose up to 400. A longer deposition time produced a lower sheet-resistance. The TaN coatings with stable sheet-resistance of 50 Ω/ were synthesized under the optimized conditions. ©, 2015, Science Press. All right reserved.