| About this Abstract |
| Meeting |
2011 Electronic Materials Conference
|
| Symposium
|
2011 Electronic Materials Conference
|
| Presentation Title |
R8, Growth and Characterization of AlInSb Metamorphic Buffers on GaSb and GaAs Substrates for the Growth of MWIR Lasers |
| Author(s) |
Stephen Clark, P. Ahiwar, V. Patel, S. Reissmann, T. J. Rotter, A. R. Albrecht, H. Xu, C. P. Hains, L. R. Dawson, Y. Picard, G. Balakrishnan |
| On-Site Speaker (Planned) |
Stephen Clark |
| Abstract Scope |
The applications of MWIR lasers include remote sensing, LADAR, trace gas sensing, intelligence, surveillance and reconnaissance (ISR) and infrared countermeasures (IRCM). Though MWIR lasers have been developed using lead (Pb) salts, and II-VI compound semiconductors, the most promising technological advances have been achieved using III-V compound semiconductor materials lattice matched to GaSb substrates. With the use these substrates, room temperature (RT) and near-room temperature operation of laser diodes has been achieved at wavelengths > 3.0 µm. Groups have tried various active regions to achieve operation at the desired wavelength range of 3 µm to 4 µm including Type I, Type II, inter-cascade, and quantum cascade. While Type I based InAsSb QW devices have been shown to operate in this range, when pumped optically, miscibility-gap issues severely affect device performance and restrict the emission wavelength to less than 3.8 µm (at 77 K). Conversely, recent advances in Type II ‘W’, quantum-cascade and inter-cascade laser technology have resulted in >100 mW CW output power at room temperature throughout the spectral range of interest. The use of antimonide metamorphic buffers has shown promise in extending the wavelength range of antimonide type-I lasers. The most successful instance of such a laser was by Lester et al. where AlInSb metamorphic buffers were used to achieve greater than 3.3μm room temperature lasing under pulsed conditions. In this abstract we present the growth and characterization of AlInSb metamorphic buffers grown on GaSb and GaAs substrates to establish a lattice constant in the 6.13 to 6.2 Å range that can then be used for the growth of >3.5 µm type-I active regions. We shall grow the buffers in the form of single step buffers (directly from GaSb to the final lattice constant) and step graded buffers. We shall also explore the growth of these buffers through the use of a digital alloy technique. A large parameter space of III:V ratios, substrate temperatures and growth rates will be used in development of these buffers. These buffers will be characterized using a variety of techniques including X-ray diffraction, atomic force microscopy (AFM), cross-section transmission electron microscopy (XTEM) and Electron Channeling Contrast Imaging (ECCI). We shall also make use of InGaSb quantum well structures to analyze the suitability of the material for laser growth. |
| Proceedings Inclusion? |
Undecided |