IRON GETTERING CONTROLLED BY SIZE AND DENSITY OF OXYGEN PRECIPITATES IN CZOCHRALSKI-GROWN SILICON

The gettering efficiency of iron (Fe) was investigated as a function o f the size and density of oxygen precipitates in Czochralski-grown sil icon (CZ-Si). During the precipitation treatments. in order to control the size rind density of oxygen precipitates. we monitored the oxygen concentration ([O-i]) so that the final [O-i] of the samples were equ al to each other. By comparing Fe concentration ([Fe]) determined by e lectron spin resonance (ESR) in the samples, we discovered that the sa mple containing precipitates of large size and low density has a stron ger gettering efficiency during cooling from a temperature of 1050 deg rees C. In contrast. the sample containing precipitates of small size and high density has a stronger gettering efficiency during isothermal annealing at 190 degrees C.