Semi-insulating In0.49Ga0.51P grown at reduced substrate temperature by low-pressure metalorganic chemical vapor deposition

High-resistivity unintentionally-doped In0.49Ga0.51P lattice matched to GaAs has been grown via low-pressure metalorganic chemical vapor deposition at a reduced growth temperature. These layers have excellent surface quality and are single crystal. The resistivity increases exponentially as the growth temperature is decreased from 550 to 490 degrees C, resulting in a resistivity of similar to 10(9) Ohm cm for samples grown at 490 degrees C. In addition, the photoluminescence intensity decreases exponentially for growth temperatures below 550 degrees C, indicating an increase in nonradiative recombination related to an increasing trap concentration. For samples grown at 550 degrees C, constant capacitance deep level transient spectroscopy measurements show a strong broad peak at similar to 200 degrees K with an ionization energy of 0.40+/-0.04 eV, verifying the presence of an electron trap. The gummel plot and I-V characteristics of an InGaP/GaAs heterojunction bipolar transistor (HBT) with a 2000-Angstrom-thick InGaP buffer layer grown at 500 degrees C are identical to that of an HBT grown without the InGaP buffer layer, indicating that the semi-insulating InGaP layer is compatible with GaAs-based device epitaxy. (C) 1997 American Institute of Physics.