GaN/AlN Multilayer Superlattices Synthesized by Pulsed Laser Molecular Beam Epitaxy
Abstract
We have synthesized GaN/AlN multilayer superlattices on sapphire where GaN is a quantum well and AlN acts as a barrier for the carriers. The well thickness has been varied in several samples while keeping the barrier thickness constant. We have grown 15 such alternate layers in each sample. Pulsed laser-MBE has been used in this work wherein stoichiometric GaN and AlN targets were ablated by UV laser (λ=248 nm) in background vacuum 5X10-10 Torr. The layer-by-layer growth of the heterostructures in laser-MBE makes it ideal for fabricating ultra thin layers such as quantum wells. The evidence of quantum wells was shown by X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). The microstructure, interfaces, well thickness and defects have been characterized by these techniques. The optical properties such as transmission, absorbance and photoluminescence have been studied.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 2000
- Bibcode:
- 2000APS..MARB18011R