Evidence for Metastabile State of DX Center in AxGa1-xAs

1992 ◽  
Vol 262 ◽  
Author(s):  
Subhasis Ghosh ◽  
Vikram Kumar

ABSTRACTPhoto-Deep Level Transient Spectroscopy with 1.38 eV light reveals a new level with thermal activation energy 0.2 eV of DX centers in silicon doped Alx Ga1-xAs (x = 0.26) for the first time. The observation of this level directly proves the negative-U properties of DX centers and the existence of thermodynamically metastable state DX.

1987 ◽  
Vol 104 ◽  
Author(s):  
John W. Farmer ◽  
Harold P. Hjalmarson ◽  
G. A. Samara

ABSTRACTPressure dependent Deep Level Transient Spectroscopy (DLTS) experiments are used to measure the properties of the deep donors (DX-centers) responsible for the persistent photoconductivity effect in Si-doped AlGaAs. The sample dependence of the DLTS spectra shows evidence for a defect complex involved in the DX-center.


1989 ◽  
Vol 67 (4) ◽  
pp. 283-286 ◽  
Author(s):  
R. V. Lang ◽  
J. D. Leslie ◽  
J. B. Webb ◽  
A. P. Roth ◽  
M. A. Sacilotti ◽  
...  

The thermal activation energy of the EL2 deep level in low-pressure metalorganic chemical vapour deposited Ga1−xInxAs epilayers has been determined by deep-level transient spectroscopy. Variation of the deposition conditions, which included a change in the substrate orientation, resulted in different dependencies of the EL2 thermal activation energy upon the epilayer indium content. In all cases a decrease in this deep-level property was observed for increasing indium content in the epilayers. Although the cause of this variation in the dependence of the thermal activation energy upon the epilayer indium content could not be identified in this work, it can be shown that it is not associated with different amounts of residual strain or impurities in the epilayers.


1991 ◽  
Author(s):  
Soraya Ababou ◽  
Taha Benyattou ◽  
Jean J. Marchand ◽  
Louis Mayet ◽  
Gerard Guillot ◽  
...  

1989 ◽  
Vol 67 (4) ◽  
pp. 375-378 ◽  
Author(s):  
C. K. Teh ◽  
F. L. Weichman ◽  
C. C. Tin ◽  
P. A. Barnes

Photoluminescence (PL), Fourier-transform infrared (FTIR), and deep-level transient spectroscopy (DLTS) measurements have been made on various samples of silicon-doped liquid-encapsulated Czochralski-grown GaAs. All the samples show prominent PL peaks at 1.443 and 1.325 eV together with their longitudinal optic (LO) phonon peaks. The PL peak at 1.443 eV has been reported in the literature as being due to either GaAs or a boron-related defect. The FTIR results show the presence of BGa at 540.3 and 517.0 cm−1 and SiGa at 383.6 cm−1. We have observed that there is no correlation between the PL peak at 1.443 eV and BGa. Thus, we believe that this PL peak is related to the GaAs antisite defect. The presence of EL2 in the samples has been measured using DLTS. We have found that the intensity of the PL peak at 1.443 eV varies inversely with that of the EL2 peak. This relationship indirectly confirms that the 1.443 eV peak is due to the gallium antisite defect. The PL peak at 1.325 eV is significantly different from those reported in the literature for GaAs:Si. Measurements have also been made on samples of GaAs:Si annealed under different arsenic overpressures.


1987 ◽  
Vol 104 ◽  
Author(s):  
A. Ben Cherifa ◽  
R. Azoulay ◽  
G. Guillot

ABSTRACTWe have studied by means of deep level transient spectroscopy and photocapacitance measurements deep electron traps in undoped Ga1−xAlxAs of n-type grown by metalorganic chemical vapor deposition with 0≤x≤ 0.3. A dominant deep electron trap is detected in the series of alloys. Its activation energy is found at EC-0.8 eV in GaAs and it increases with x. Its concentration is found nearly independent of x. For the first time we observed for this level in the Ga1−xAlxAs alloys, the photocapacitance quenching effect typical for the EL2 defect in GaAs thus confirming clearly that EL2 is also created in MOCVD Ga1−xAlxAs.


2012 ◽  
Vol 717-720 ◽  
pp. 251-254 ◽  
Author(s):  
Bernd Zippelius ◽  
Alexander Glas ◽  
Heiko B. Weber ◽  
Gerhard Pensl ◽  
Tsunenobu Kimoto ◽  
...  

Deep Level Transient Spectroscopy (DLTS) and Double-correlated DLTS (DDLTS) measurements have been conducted on Schottky contacts fabricated on n-type 4H-SiC epilayers using different contact metals in order to separate the EH6- and EH7-centers, which usually appear as a broad double peak in DLTS spectra. The activation energy of EH6(EC- ET(EH6) = 1.203 eV) turns out to be independent of the electric field. As a consequence, EH6is acceptor-like according to the missing Poole-Frenkel effect. Therefore, it can be excluded that the EH6-center and the prominent acceptor-like Z1/2-center belong to different charge states of the same microscopic defect as theoretically suggested. It is proposed that EH6is a complex containing a carbon vacancy and another component available at high concentrations. The activation energy of EH7(EC- ET(EH7) = 1.58 eV) has been evaluated indirectly by fitting the DLTS spectra of the EH6/7double peak taking the previously determined parameters of EH6into account.


1993 ◽  
Vol 312 ◽  
Author(s):  
P. Krispin ◽  
R. Hey ◽  
H. Kostial ◽  
M. Höricke

AbstractWe report on a detailed investigation of MBE-grown isotype silicon-doped heterostructures by capacitance/voltage (C/V) technique and deep-level transient spectroscopy (DLTS). A sequence of electrically active defects is found. By depth profiling of the density of the dominant levels it is demonstrated that the corresponding defects are concentrated at the GaAs-on-AlAs (inverted) interface. By comparison with studies on irradiation-induced levels in LPE- or VPE-grown AlGaAs we conclude that the defects at the GaAs/AlAs interface are most probably linked to different charge states of the arsenic vacancy VAs and VAs−ASi pairs.


1988 ◽  
Vol 27 (Part 1, No. 5) ◽  
pp. 738-745 ◽  
Author(s):  
Michihiro Fudamoto ◽  
Kenichiro Tahira ◽  
Jun Morimoto ◽  
Toru Miyakawa

2001 ◽  
Vol 699 ◽  
Author(s):  
Florentina Perjeru ◽  
Xuewen Bai ◽  
Martin E. Kordesch

AbstractWe report the electronic characterization of n-ScN in ScN-Si heterojunctions using Deep Level Transient Spectroscopy of electrically active deep levels. ScN material was grown by plasma assisted physical vapor deposition and by reactive sputtering on commercial p+ Si substrates. Deep level transient spectroscopy of the junction grown by plasma assisted physical vapor deposition shows the presence of an electronic trap with activation energy EC-ET= 0.51 eV. The trap has a higher concentration (1.2–1.6 1013cm−3) closer to the ScN/Si interface. Junctions grown by sputtering also have an electronic trap, situated at about EC-ET= 0.90 eV.


Sign in / Sign up

Export Citation Format

Share Document