The effect of the de bias on the compositional ratio, resistivity, and deposition rate for tungsten nitride (WNX) films prepared by rf-dc coupled magnetron sputtering have been investigated in detail. The value of the film compositional ratio (N/W) is significantly decreased from 0.8 to 0.2 with increasing the target de bias voltage. The increase of the target de bias voltage from -100 to -500 V results in a dramatical decrease in the resistivity of WNX films. It is shown that the N/W ratio and the resistivity of WNX thin films deposited at the target de bias voltage of -200 V are about 0.5 and 370 mu Omega cm, respectively