HYDROGEN ENHANCEMENT OF SILICON THERMAL DONOR FORMATION

Oxygen-related thermal donor formation in Czochralski silicon is chara cterized by the capacitance-voltage and deep level transient spectrosc opy techniques as a function of 450-degrees-C anneal time following hy drogenation. Increases in the formation rate and number of thermal don or (TD) defects found after hydrogenation are reported. This study fin ds an increase in TD+/++ concentration in the near-surface region at s hort anneal times, but at longer times an elevated concentration was n ot observed. No acceleration through the sequence of thermal donor def ects was detected. This fails to support the model of hydrogen lowerin g the barrier to oxygen diffusion and accelerating the TD(n)-->TD(n+1) transitions. This study does, however, support a model in which the h ydrogen increases the available thermal donor core sites.