By Topic

Influence of Al doping on lattice strain and electrical properties of epitaxial GaN films grown by metalorganic chemical vapor deposition on Al2O3 substrate

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

The purchase and pricing options are temporarily unavailable. Please try again later.
7 Author(s)
Jeong, Jae Kyeong ; School of Materials Science and Engineering and Inter-University Semiconductor Research Center, Seoul National University, Seoul 151-742, Korea ; Choi, Jung-Hae ; Seong Hwang, Cheol ; Joon Kim, Hyeong
more authors

Your organization might have access to this article on the publisher's site. To check, click on this link: 

The effects of the isoelectronic Al doping of epitaxial GaN films grown by metalorganic chemical vapor deposition on a (0001) Al2O3 single crystal substrate were investigated. It was found that the threading screw and edge dislocation densities of the GaN film decreased to less than half of that of the undoped GaN film up to Al doping concentration of 0.45%. The in-plane and out-of-plane strains were simultaneously reduced with the decrease in dislocation density as a result of the solution hardening effect. Accordingly, the electron mobility of the 0.45% Al-doped GaN film (524 cm2/Vs) was greatly improved compared to that of the undoped GaN film (178 cm2/Vs). However, the threading dislocation densities and strains were increased at a 0.64% Al concentration, and the electron mobility decreased accordingly. Therefore, the improvement in the electron mobility by Al doping up to 0.45% is the result of a decrease in the threading dislocation density and not a decrease in the number of point defects (Ga-site vacancy) as suggested earlier [Lee etal, Appl. Phys. Lett. 83, 917 (2003)]. © 2004 American Institute of Physics.

Published in:

Applied Physics Letters  (Volume:84 ,  Issue: 14 )