Growth of p-type GaAs/AlGaAs(111) quantum well infrared photodetector using solid source molecular-beam epitaxy

Journal Article · Thu Sep 01 04:00:00 EDT 2005 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.2034652· OSTI ID:20714097

Li, H; Mei, T; Karunasiri, G; Fan, W J; Zhang, D H; Yoon, S F; Yuan, K H ^[1]

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1. School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, 639798 (Singapore)

A p-type GaAs/AlGaAs multi-quantum-well infrared photodetector (QWIP) was fabricated on a GaAs (111)A substrate by molecular-beam epitaxy using silicon as dopant. The same structure was also grown on a GaAs (100) wafer simultaneously to compare the material and structural properties. It was found that Si acts as a p-type dopant in the GaAs (111)A sample while it is n-type in the GaAs (100) counterpart. The growth rate was found to be appreciably enhanced for GaAs (111)A compared with that of GaAs (100) orientation, while the Al composition in the barriers was found to be 20% smaller for a (111) orientation which results in a smaller barrier height. A peak responsivity of 1 mA/W with a relatively wide wavelength response ({delta}{lambda}/{lambda}{sub p}{approx}53%) was observed for the GaAs (111)A QWIP, mainly due to the location of the excited state far above the barrier. The photoresponse also showed a relatively strong normal incident absorption probably originating from the mixing of the conduction and valence Bloch states. The optimization of the quantum well parameters should further enhance the responsivity of this p-type QWIP with Si as dopant species.

• OSTI ID: 20714097
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 5 Vol. 98; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ABSORPTION
ALUMINIUM ARSENIDES
COMPARATIVE EVALUATIONS
CRYSTAL GROWTH
EXCITED STATES
GALLIUM ARSENIDES
GRAIN ORIENTATION
MIXING
MOLECULAR BEAM EPITAXY
OPTIMIZATION
PHOTODETECTORS
QUANTUM WELLS
SEMICONDUCTOR MATERIALS
SILICON
SUBSTRATES
VALENCE
WAVELENGTHS