Highly C-doped (001)-oriented layers were grown by means of low-pressure metal-organic vapor-phase epitaxy, using precursor trimethylgallium to obtain C concentrations of more than 1020/cm3. Post-growth infra-red measurements, using polarized light, demonstrated that grown-in planar C-H complexes, H-(CAs)2, produced a vibrational absorption at 2688/cm. These had two CAs atoms aligned along the [110] direction. This orientation was orthogonal to that which had been found previously for samples that had been grown by metal-organic molecular beam epitaxy onto a (001)-(2 x 4) reconstructed surface. The formation of the complex was attributed to incomplete decomposition of the trimethylgallium.

B.R.Davidson, R.C.Newman, K.H.Bachem: Physical Review B, 1995, 52[7], 5179-82