TRI-ISOPROPYL GALLIUM - A VERY PROMISING PRECURSOR FOR CHEMICAL BEAM EPITAXY

The first reported use of tri-isopropyl gallium (TiPGa) in chemical beam epitaxy (CBE) is described. Hall measurements performed on the resulting undoped GaAs epitaxial layers indicate an order of magnitude reduction in unintentional carbon impurity levels compared to structures grown under comparable conditions using the standard CBE precursor, triethyl gallium. 2 K photoluminescence spectra match those recorded elsewhere from state-of-the-art high purity GaAs material grown by molecular beam epitaxy, and 77 K Hall measurements on intentionally n-type doped GaAs layers confirm residual acceptor levels in the low 10(14) cm-3 range. The early data obtained already provide a clear indication of the important potential of TiPGa as an improved precursor for the CBE growth of Ga-containing III-V materials.