DAMAGE CAUSED BY STORED CHARGE DURING ECR PLASMA-ETCHING

The influence of stored charge caused by changing the plasma parameter can be accurately shown by measuring the leakage current in CMOS-inverter integrated circuits. The leakage current increase is due to nonuniform ion current density distribution and self-bias voltage at the point of ECR plasma discharge turn-off. Positive charge ions are stored by the ion current density difference on a wafer. Moreover, a large voltage across the gate oxide is generated by the self-bias voltage at the point of ECR plasma discharge turn-off, and finally degrades the gate oxide. © 1990 The Japan Society of Applied Physics.