Growth by Liquid-Phase Epitaxy and Characterization of Al 0.28 Ga 0.72 As 0.62 P 0.38

• Published in: Japanese Journal of Applied Physics Vol. 31; no. 8R; p. 2514
• Main Authors: Chen, Chyuan-Wei, Meng-Chyi Wu, Meng-Chyi Wu, Li-Kuang Kuo, Li-Kuang Kuo
• Format: Journal Article
• Language: English
• Published: 01.08.1992
• ISSN: 0021-4922; 1347-4065
• DOI: 10.1143/JJAP.31.2514

Al 0.28 Ga 0.72 As 0.62 P 0.38 epitaxial layers were grown on GaAs 0.61 P 0.39 substrates by liquid-phase epitaxy using a supercooling technique. The growth conditions and properties of the undoped AlGaAsP layers are described in detail. A fairly shiny surface and a flat AlGaAsP-GaAsP heterointerface was obtained in our study. The lattice mismatch normal to the wafer surface between the Al 0.28 Ga 0.72 As 0.62 P 0.38 layer and GaAs 0.61 P 0.39 substrate is ∼+0.27%. Low-electron-concentration undoped epitaxial layers can be grown from a Ga solution baked at a temperature of 900°C for 10 h or more and with a ∼6°C supersaturation temperature. We obtained the lowest electron concentrations of 1×10 16 cm -3 measured by the capacitance-voltage method. By the photoluminescence measurements at various temperatures and excitation levels, the four recombination peaks observed are associated with the near-band-to-band, donor-to-valence-band, conduction-band-to-acceptor and donor-to-acceptor-pair transitions. The band gap of the Al 0.28 Ga 0.72 As 0.62 P 0.38 is ∼2.016 eV (6150 Å). The binding energy of the donor and acceptor is 14 and 36 meV, respectively.