Structural and compositional analysis of InBi xAs ySb (1− x− y) films grown on GaAs(0 0 1) substrates by liquid phase epitaxy

• Published in: Applied surface science Vol. 220; no. 1; pp. 321 - 326
• Main Authors: Dixit, V.K., Keerthi, K.S., Bhat, H.L., Bera, Parthasarathi, Hegde, M.S.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 2003
• Subjects: Antimonides; Liquid phase epitaxy; Semiconducting III–V materials; X-ray diffraction; Liquid phase epitaxy; 81.15Lm; X-ray diffraction; Antimonides; 81.05Ea; Semiconducting III–V materials
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/S0169-4332(03)00829-8

The growth of epitaxial InBi x As y Sb (1− x− y) layers on highly lattice mis-matched semi-insulating GaAs substrates has been successfully achieved via the traditional liquid phase epitaxy. Orientation and single crystalline nature of the film have been confirmed by X-ray diffraction. Scanning electron micrograph shows abrupt interface at micrometer resolution. Surface composition of Bi( x) and As( y) in the InBi x As y Sb (1− x− y) film was measured using energy dispersive X-ray analysis and found to be 2.5 and 10.5 at.%, respectively, and was further confirmed with X-ray photoelectron spectroscopy. Variation of the composition with depth of the film was studied by removing the layers with low current (20 μA) Ar + etching. It was observed that with successive Ar + etching, In/Sb ratio remained the same, while the As/Sb and Bi/Sb ratios changed slightly with etching time. However after about 5 min etching the As/Sb and Bi/Sb ratios reached constant values. The room temperature band gap of InBi 0.025As 0.105Sb 0.870 was found to be in the range of 0.113–0.120 eV. The measured values of mobility and carrier density at room temperature are 3.1×10 4 cm 2 V −1 s −1 and 8.07×10 16 cm −3, respectively.