Characteristics of Step-Graded InxGa1-xAs and InGaPySb1-y Metamorphic Buffer Layers on GaAs Substrates

Conference: IPRM 2011 - 23th International Conference on Indium Phosphide and Related Materials
05/22/2011 - 05/26/2011 at Berlin, Germany

Proceedings: IPRM 2011

Pages: 4Language: englishTyp: PDF

Personal VDE Members are entitled to a 10% discount on this title

Authors:
Kirch, J.; Kim, T.; Mawst, L. J. (Department of Electrical and Computer Engineering, University of Wisconsin - Madison, 1415 Engineering Dr., Madison, Wisconsin 53706, USA)
Dudley, P. (Materials Science Program, University of Wisconsin - Madison, 1415 Engineering Dr., Madison, Wisconsin 53706, USA)
Radavich, K.; Ruder, S.; Kuech, T. F. (Department of Chemical and Biological Engineering, University of Wisconsin - Madison, 1415 Engineering Dr., Madison, Wisconsin 53706, USA)
LaLumondiere, S. D.; Sin, Y.; Lotshaw, W. T.; Moss, S. C. (Electronics and Photonics Lab, The Aerospace Corporation, El Segundo, CA 90245, USA)

Abstract:
Abstract. Step-graded InGaPySb1-y and InxGa1-xAs metamorphic buffer layer (MBL) structures are grown on GaAs substrates by metal-organic chemical vapor deposition (MOCVD). AFM analysis indicates that graded group V InGaPySb1-y MBLs exhibit significantly lower surface roughness (~4.7nm) compared with more conventional graded group III InxGa1-xAs MBLs, which typically have rms surface roughness in the range of 7-14nm. To reduce the surface roughness of the InxGa1-xAs MBL, a post growth Chemical-Mechanical Polishing (CMP) procedure is implemented. AFM image analysis indicates the CMP process is effective in reducing the step-graded InxGa1-xAs MBL surface roughness from ~7.3 nm (as-grown) to 2.3 nm post CMP. Preliminary studies indicate that bulk InGaAs layers regrown on top of the MBL subjected to CMP exhibit improved static and transient PL characteristics compared with those deposited on as-grown MBLs.