GaN thin films by growth on Ga rich GaN buffer layers

Journal Article · Sat Jul 01 04:00:00 EDT 2000 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.1319162· OSTI ID:834298

Kim, Yihwan ^[1]; Subramanya, Sudhir G; Siegle, Henrik; Kruger, Joachim; Perlin, Piotr; Weber, Eicke R; Ruvimov, Sergei; Liliental-Weber, Zuzanna

---

1. LBNL Library

The influence of the composition of the low-temperature GaN buffer layer on the structural, electrical, and optical properties of the subsequently grown GaN epilayer by molecular beam epitaxy is investigated. It is found that decreasing the N/Ga flux ratio during the buffer layer growth yields excess Ga in the buffer layer. GaN epilayers grown on the buffer layer with excess Ga showed increased electron Hall mobility and reduced threading dislocation density. The tilt and twist disorders of the epilayer were also significantly reduced. The compressive stress in the epilayers at room temperature increased as the N/Ga flux ratio during the buffer layer growth was reduced. The improved properties of the epilayers are explained by the hypothesis that excess Ga in the buffer layer facilitates stress relaxation at the epilayer growth temperature.

• Research Organization: Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA (US)
• Sponsoring Organization: USDOE Director. Office of Science. Office of Basic Energy Sciences. Division of Materials Sciences; National Science Foundation; German Academic Exchange Service (US)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 834298
• Report Number(s): LBNL--46832
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 10 Vol. 88; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BUFFERS
DISLOCATIONS
ELECTRONS
GAN MOLECULAR BEAM EPITAXY LOW TEMPERATURE GAN BUFFER LAYER
HYPOTHESIS
MOLECULAR BEAM EPITAXY
OPTICAL PROPERTIES
STRESS RELAXATION
THIN FILMS