Low Pressure Chemical Vapor Deposition of III/V‐Nitrides Using Organometallics and Hydrazoic Acid Precursors

In and Ga nitride films have been deposited on various substrates using organometallics and hydrazoic acid (HN₃) as nitrogen precursor. The film deposition was carried out under low pressure (10⁻⁵10 ⁻⁶ Torr) and low V/III ratios (1‐10). XPS analysis indicated that the ln(Ga):N atomic ratio of unity can be easily achieved by adjusting the experimental conditions. For the growth of InN on Si(100) substrate, 308‐nm photon beam is needed to speed up the film deposition rate. He(II) UPS spectra of InN films are in good agreement with the result of a pseudo‐potential calculation for InN valence band, while the spectra of GaN compare favorably with a recent semi‐ab‐initio calculation and with the UPS results of GaN single crystal films. The bandgap of our GaN films is ∼ 3.3 cV as determined by photoluminescence and UV‐VIS absorption spectra. Raman spectra taken from GaN Films showed peaks at 66 and 88 meV for TO and LO phonons, respectively, indicating a wurtzite structure of the GaN. In a corresponding X‐ray diffraction spectrum, the (002) peak is about 400 times more intense than that of the (101) peak, suggesting that the GaN layers are highly oriented with the c‐axis normal or nearly so to the Al₂O₃ substrate.