[en] Conductivity and Hall effect measurements were performed before and after Si3N4 passivation of intentionally undoped and doped AlGaN/GaN heterostructures on Si and SiC substrates. An increase of the sheet carrier density ~up to ;30%! and a slight decrease of the electron mobility ~less than 10%! are found in all samples after passivation. The passivation induced sheet carrier density is 1.5– 231012 cm22 in undoped samples and only 0.731012 cm22 in 5–1031018 cm23 doped samples. The decrease of the electron mobility after passivation is slightly lower in highly doped samples. The channel conductivity in both types of unpassivated samples on Si and SiC substrates increases with an increase in doping density. After passivation, a well-resolved increase of channel conductivity is observed in the undoped or lightly doped samples and nearly the same channel conductivity results in the highly doped samples.
Disciplines :
Electrical & electronics engineering
Identifiers :
UNILU:UL-ARTICLE-2009-308
Author, co-author :
Bernat, J.; Institute of Thin Films and Interfaces (ISG-1), Research Centre Ju¨lich, D-52425 Ju¨lich, Germany
Javorka, P.; Institute of Thin Films and Interfaces (ISG-1), Research Centre Ju¨lich, D-52425 Ju¨lich, Germany
Marso, Michel ; Institute of Thin Films and Interfaces (ISG-1), Research Centre Ju¨lich, D-52425 Ju¨lich, Germany
Kordos, P.; Institute of Thin Films and Interfaces (ISG-1), Research Centre Ju¨lich, D-52425 Ju¨lich, Germany
Language :
English
Title :
Conductivity and Hall effect measurements on intentionally undoped and doped AlGaN/GaN heterostructures before and after passivation,
Publication date :
2003
Journal title :
Applied Physics Letters
ISSN :
0003-6951
Publisher :
American Institute of Physics, Melville, United States - New York