Characterization of Oxide Precipitates in Heavily B-Doped Silicon by Infrared Spectroscopy (original) (raw)

Infrared absorption spectra of oxygen precipitates in boron-doped silicon with a boron concentration between 10 17 and 10 19 cm Ϫ3 are analyzed, applying the spectral function representation of composite materials. The aspect ratio of the platelet precipitates is determined by transmission electron microscopy measurements. The analysis shows that in samples with moderate doping levels (Ͻ10 18 B cm Ϫ3 ͒ SiO ␥ precipitates are formed with the same composition as in the lightly doped case. In the heavily boron-doped (Ͼ10 18 cm Ϫ3 ͒ samples, however, the measured spectra of the precipitates are consistent with a mixture of SiO 2 and B 2 O 3 , with a volume fraction of B 2 O 3 as high as 0.41 in the most heavily doped case.