The defect concentration in thin GaN layers was estimated by means of positron annihilation spectroscopy. Positron lifetime and Doppler broadening of the annihilation radiation were used. A comparative study of GaN films grown with different techniques was performed. Specific attention has been given to the new low energy plasma enhanced vapor phase epitaxy (LEPEVPE) growth technique. A very high Ga vacancy density (1019 cm−3) was found in a thin GaN layer directly grown by LEPEVPE on a sapphire substrate. However, when a GaN substrate (commercial sample grown by Metal Organic Vapor Phase Epitaxy) is used as a template for LEPEVPE deposition, the vacancy density of the film is low (about 1016 cm−3). This fact provides evidences that the LEPEVPE technique is able to produce high quality GaN layers.
Skip Nav Destination
Article navigation
15 July 2012
Research Article|
July 20 2012
Characterization of vacancy-type defects in heteroepitaxial GaN grown by low-energy plasma-enhanced vapor phase epitaxy
A. Calloni;
A. Calloni
1
LNESS and CNISM, Dipartimento di Fisica, Politecnico di Milano
, Via Anzani 42, 22100 Como, Italy
Search for other works by this author on:
R. Ferragut;
R. Ferragut
a)
1
LNESS and CNISM, Dipartimento di Fisica, Politecnico di Milano
, Via Anzani 42, 22100 Como, Italy
Search for other works by this author on:
A. Dupasquier;
A. Dupasquier
1
LNESS and CNISM, Dipartimento di Fisica, Politecnico di Milano
, Via Anzani 42, 22100 Como, Italy
Search for other works by this author on:
H. von Känel;
H. von Känel
2
Laboratory for Solid State Physics, ETH Zurich
, CH-8093 Zurich, Switzerland
3
EpiSpeed SA
, Technoparkstrasse 1, CH-8005 Zürich, Switzerland
Search for other works by this author on:
A. Guiller;
A. Guiller
b)
3
EpiSpeed SA
, Technoparkstrasse 1, CH-8005 Zürich, Switzerland
Search for other works by this author on:
A. Rutz;
A. Rutz
3
EpiSpeed SA
, Technoparkstrasse 1, CH-8005 Zürich, Switzerland
Search for other works by this author on:
L. Ravelli;
L. Ravelli
4
Institut für Angewandte Physik und Messtechnik, Universität der Bundeswehr München
, Werner Heisenberg-Weg 39, D-85577 Neubiberg, Germany
Search for other works by this author on:
W. Egger
W. Egger
4
Institut für Angewandte Physik und Messtechnik, Universität der Bundeswehr München
, Werner Heisenberg-Weg 39, D-85577 Neubiberg, Germany
Search for other works by this author on:
a)
Author to whom correspondence should be addressed. Electronic mail: rafael.ferragut@polimi.it.
b)
Present address: Oerlikon Solar Ltd, Trubbach, Hauptstrasse 1a, CH-9477 Trubbach, Switzerland.
J. Appl. Phys. 112, 024510 (2012)
Article history
Received:
December 18 2011
Accepted:
June 14 2012
Citation
A. Calloni, R. Ferragut, A. Dupasquier, H. von Känel, A. Guiller, A. Rutz, L. Ravelli, W. Egger; Characterization of vacancy-type defects in heteroepitaxial GaN grown by low-energy plasma-enhanced vapor phase epitaxy. J. Appl. Phys. 15 July 2012; 112 (2): 024510. https://doi.org/10.1063/1.4737402
Download citation file:
Sign in
Don't already have an account? Register
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Sign in via your Institution
Sign in via your InstitutionPay-Per-View Access
$40.00