Premium
Photoreflectance studiesof N‐ and Ga‐face AlGaN/GaN heterostructures confininga polarisation induced 2DEG
Author(s) -
Winzer A. T.,
Goldhahn R.,
Buchheim C.,
Ambacher O.,
Link A.,
Stutzmann M.,
Smorchkova Y.,
Mishra U. K.,
Speck J. S.
Publication year - 2003
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.200303351
Subject(s) - heterojunction , conduction band , polarization (electrochemistry) , materials science , acceptor , polarity (international relations) , piezoelectricity , electric field , condensed matter physics , electron , chemistry , optoelectronics , physics , biochemistry , quantum mechanics , composite material , cell
Photoreflectance measurements have been carried out in order to determine the electric field strength F within the topmost layers of Ga‐face polarity Al x Ga 1− x N/GaN and N‐face polarity GaN/Al x Ga 1 − x N/GaN heterostructures containing high‐mobile polarisation induced 2DEGs. For both types of samples F decreased from 400 kV/cm at room temperature up to 200 kV/cm when cooling down the structure to T = 5 K. Our results strongly emphasise the existence of surface donor and surface acceptor states of the Ga‐ and N‐face samples, respectively. The temperature dependence of F is explained by the change of the piezoelectric and spontaneous polarization. From self‐consistent conduction band calculations the bare surface potential was obtained. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Accelerating Research
Robert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom
Address
John Eccles HouseRobert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom