PLASMA IMMERSION ION-IMPLANTATION REACTOR DESIGN CONSIDERATIONS FOR OXIDE CHARGING

The effects of wafer bias and plasma parameters on thin oxide charging during plasma immersion ion implantation (PIII) are simulated. The si mulator has been shown to determine accurately the charging currents g enerated during PIII. The dependence of the plasma electron temperatur e, ion density and plasma uniformity on charging damage in metal oxide semiconductor capacitor structures is investigated. A lower plasma el ectron temperature is shown to reduce charging damage. Simulation and experimental results show that for a given voltage pulse waveform ther e is a range of bias repetition rates allowed by limiting the charging damage below a threshold value. Within this range there exists a swit ch-over repetition rate that minimizes the charging damage.