Title :
A study of defects in AlGaN/GaN heterostructures
Author :
Na, J.H. ; Lee, H.S. ; Jeon, H.C. ; Jeong, Y.S. ; Park, C.J. ; Park, Y.S. ; Cho, H.Y. ; Kang, T.W. ; Oh, J.E. ; Chung, K.S. ; Lee, K.H.
Author_Institution :
Dept. of Phys., Dongguk Univ., Seoul, South Korea
Abstract :
The authors study defects in AlGaN/GaN heterostructures using DLTS. The AlGaN/GaN heterostructures used were grown by RF-plasma assisted molecular beam epitaxy (PA-MBE) on sapphire substrates. The Al mole fraction was kept at 0.2 for all the AlGaN layers. Two electron traps were detected. The trap levels are E/sub c/-0.15eV and E/sub c/-0.25eV, respectively. These traps are attributed to point defects and dislocations through analysing DLTS features such as the measured fill pulse time. The trap related to the dislocation was reduced by annealing.
Keywords :
III-V semiconductors; aluminium compounds; deep level transient spectroscopy; defect states; electron traps; gallium compounds; plasma deposited coatings; semiconductor epitaxial layers; semiconductor heterojunctions; wide band gap semiconductors; Al mole fraction; Al/sub 2/O/sub 3/; AlGaN-GaN; AlGaN/GaN heterostructures; DLTS; RF-PA-MBE; RF-plasma assisted molecular beam epitaxy; defects; dislocations; electron traps; point defects; sapphire substrates; Aluminum gallium nitride; Annealing; Electron traps; Gallium nitride; Physics; Pulse measurements; Temperature dependence; Time measurement; Voltage; Wide band gap semiconductors;
Conference_Titel :
Molecular Beam Epitaxy, 2002 International Conference on
Conference_Location :
San Francisco, CA, USA
Print_ISBN :
0-7803-7581-5
DOI :
10.1109/MBE.2002.1037823
