EFFECTS OF O-2 ON THE (113) DEFECT FORMATION IN SI OBSERVED BY IN-SITU ULTRAHIGH-VACUUM TRANSMISSION ELECTRON-MICROSCOPY

The nucleation and growth of the {113} defects in floating zone Si hav e been observed in situ in a ultrahigh vacuum (UHV) transmission elect ron microscopy. After the surfaces of a Si foil are controlled, intens e irradiation of 200 keV electrons proceeds at 400 or 500 degrees C in the base pressure of 1.0x10(-7) Pa. We have found that the defect dev elopment changes prominently after O-2 is injected in a specimen chamb er, While O-2 flows, the pressure is kept at about 5.0x10(-5) Pa. This result has brought direct evidence for the effect of O-2 On formation of the defects, since no other impurities are involved in the UHV env ironment. (C) 1997 American Institute of Physics.