Characterisation of Be-doped GaInAs/AlGaAs multiple quantum well structures and GaInAsP layers grown by solid source molecular beam epitaxy

• Main Author: Shi, Wei.
• Other Authors: Zhang, Dao Hua
• Format: Theses and Dissertations
• Published: 2008
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Optics, optoelectronics, photonics
• Online Access: http://hdl.handle.net/10356/3246
• Institution: Nanyang Technological University

Electrical, optical and structural properties of the Be-doped GalnAs/AlGaAs strained multiple quantum-well structures (MQWs) with different doping densities in the GalnAs wells, were systematically investigated. Extensive optical characterisation revealed that higher Be-doping densities in the well were found to enhance compressive strain and increase barrier height of the GalnAs/AlGaAs MQWs. The experimental results were verified by our theoretical calculation. The infrared absorption wavelength of the p-type GalnAs/AlGaAs strained MQW structures was found to vary from 8.35 (lm to 8.2 |im and 8.0 jxm as the Be-doping density increases from 1x10 cm" to 1x10 cm" and 2x10 cm" , respectively. These observations are in good agreement with the theoretical estimations based on the six-band Luttinger-Kohn model when the Be-doping effects were taken into account. The agreements indicated that the Be-doping effects were successfully applied into the Luttinger-Kohn model. In addition, the high Be doping density in the well may deteriorate the interface quality and/or enhance the impurity diffusion and defects. This was verified by the line width of the photoluminescence, X-ray satellite peak and infrared absorption spectra.