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M10.4.1

INTERBAND TRANSITIONS IN GaInNAs/GaAs SINGLE QUANTUM WELLS M. O. Manasreh*, D. J. Friedman**, W. Q. Ma***, C. L. Workman***, C. E. George***, and G. J. Salamo*** * Department of Electrical and Computer Engineering, University of New Mexico, Albuquerque, NM 87131 ** National Renewable Energy Laboratory, 1617 Cole Boulevards, Golden, CO 80401 *** Department of Physics, University of Arkansas, Fayetteville, AR 72701

ABSTRACT Photoluminescence (PL) spectra of interband transitions in GaInNAs/GaAs single quantum wells grown by metalorganic chemical vapor deposition technique on semiinsulating GaAs substrates were measured at 77 K for several samples grown with different In composition and dimethylhydrazine (DMH)/III ratios. The results show that the PL intensity increases as the In mole fraction is increased from 0 to 25%, but the PL intensity is degraded for samples with an In mole fraction of 30% or higher. The peak position energies of the PL spectra were investigated as a function of the DMH/III ratio. Thermal annealing effect induced a blue-shift in the PL spectra peak position energy in samples grown with high DMH/III ratio.

INTRODUCTION Diluted or small band gap nitride semiconductors such as GaInNAs and GaNAs are currently being investigated for their optoelectronic applications such as 1.3 and 1.55 µm emitters used for optical communication. Devices based on this class of materials possess advantages over other material systems. For example, the higher temperature characteristic GaInNAs/GaAs lasers provides an advantage over the GaInPAs/InP lasers. The InGaNAs/GaAs system has a larger conduction band offset, which provides a higher quantum confinement.1 The GaInNAs-based system is grown on GaAs substrate which is more robust substrates as compared to the InP substrates. Bragg reflectors are easy to fabricate for GaInNAs/GaAs vertical cavity surface emitting lasers compared to GaInPAs/InP Bragg reflectors.2 The investigation of GaInNAs/GaAs system was motivated by the fabrication of light emitters that can cover the entire visible spectral range based on the direct band-gap materials. Recently, emission was observed in GaInNAs/GaAs quantum wells (see for example Refs. 3-7) and quantum dots (see for example Refs. 8 - 10). Thermal annealing effect on the photoluminescence spectra was also investigated by various groups (see for example Refs. 4, 11-14). From various reports on the growth and characterization of the InGaNAs/GaAs system, it is realized that nitrogen incorporation leads to a number of properties that were found to be attractive for device applications. In this article, we report on the photoluminescence (PL) of GaInNAs/GaAs single quantum wells grown on semi-insulating GaAs substrates. The PL spectra were investigated at 77K as a function of In composition, dimethylhydrazine (DMH)/III ratios,

M10.4.2

and thermal annealing. The PL intensity, full width at half maximum, and the peak position energy were all found to strongly depend on the incorporation of In and N atoms. EXPERIMENTAL TECHNI