Relationship between barrier thickness and crystal quality in InGaAs/InGaAsP strained multi-quantum well structure

• Published in: Japanese Journal of Applied Physics 1993-03, Vol.32 (3B), p.L408-L410
• Main Authors: SUZAKI, S, KATARE GOPALRAO RAVIKUMAR, SEKIGUCHI, T, AIZAWA, T, YAMAUCHI, R
• Format: Article
• Language: English
• Subjects: Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Physics; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 0021-4922; 1347-4065
• DOI: 10.1143/jjap.32.l408

The barrier layer thickness dependence on crystal quality of the multi-quantum well (MQW) structure with compressively strained InGaAs wells and InGaAsP (λ g =1.15 µm) barriers is investigated. The lattice mismatch Δ a / a for a 15-period MQW structure with a 1%-strained 5 nm InGaAs (In 0.68 Ga 0.32 As) well layer is improved by increasing the thickness of the barrier layer, and it becomes saturated over 15 nm to around 0.2%. The X-ray diffraction peak intensity becomes saturated over 10 nm. The strongest exciton peak intensity and the sharpest peak width are observed for a 10 nm barrier. The optimum well volume ratio for a MQW, shown as W /( W + B ), is around 0.3 from the results of the X-ray diffraction peak intensity and the exciton peak width and intensity ( W : well thickness, B : barrier thickness).