Pressure-dependent DLTS Experiments on Si-DOPED AlGaAs

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.

Download Full-text

Evidence for Metastabile State of DX Center in AxGa1-xAs

MRS Proceedings ◽

10.1557/proc-262-579 ◽

1992 ◽

Vol 262 ◽

Author(s):

Subhasis Ghosh ◽

Vikram Kumar

Keyword(s):

Activation Energy ◽

Deep Level Transient Spectroscopy ◽

Thermal Activation ◽

Deep Level ◽

Thermal Activation Energy ◽

Dx Centers ◽

Dx Center ◽

Transient Spectroscopy ◽

Silicon Doped ◽

First Time

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.

Download Full-text

Persistent Photoconductivity And Thermal Recovery Kinetics Of Low Energy Ar + Bombarded GaAs

MRS Proceedings ◽

10.1557/proc-223-203 ◽

1991 ◽

Vol 223 ◽

Author(s):

A. Vaseashta ◽

L. C. Burton

Keyword(s):

Deep Level Transient Spectroscopy ◽

Deep Level ◽

Thermal Recovery ◽

Low Energy ◽

Persistent Photoconductivity ◽

Transport Parameters ◽

Excellent Correlation ◽

Proposed Model ◽

Transient Spectroscopy ◽

Kinetics Of

ABSTRACTKinetics of persistent photoconductivity, photoquenching, and thermal and optical recovery observed in low energy Ar+ bombarded on (100) GaAs surfaces have been investigated. Rate and transport equations for these processes were derived and simulated employing transport parameters, trap locations and densities determined by deep level transient spectroscopy. Excellent correlation was obtained between the results of preliminary simulation and the experimentally observed values. The exponential decay of persistent photoconductivity response curve was determined to be due to metastable electron traps with longer lifetime and is consistent with an earlier proposed model.

Download Full-text

Traps in Si-doped AlxGa1-xN Grown by Molecular Beam Epitaxy on Sapphire Characterized by Deep Level Transient Spectroscopy

MRS Proceedings ◽

10.1557/proc-0955-i15-30 ◽

2006 ◽

Vol 955 ◽

Author(s):

Mo Ahoujja ◽

S Elhamri ◽

M Hogsed ◽

Y. K. Yeo ◽

R. L. Hengehold

Keyword(s):

Molecular Beam Epitaxy ◽

Deep Level Transient Spectroscopy ◽

Molecular Beam ◽

Deep Level ◽

Unknown Origin ◽

Shallow Donor ◽

Related Point ◽

Line Defects ◽

Si Doped ◽

Transient Spectroscopy

ABSTRACTDeep levels in Si doped AlxGa1−xN samples, with Al mole fraction in the range of x = 0 to 0.30, grown by radio-frequency plasma activated molecular beam epitaxy on sapphire substrates were characterized by deep level transient spectroscopy (DLTS). DLTS measurements show two significant electron traps, P1 and P2, in AlGaN at all aluminum mole fractions. The electron trap, P2, appears to be a superposition of traps A and B , both of which are observed in GaN grown by various growth techniques and are thought to be related to VGa-shallow donor complexes. Trap P1 is related to line defects and N-related point defects. Both of these traps are distributed throughout the bulk of the epitaxial layer. An additional trap P0 which was observed in Al0.20Ga0.80N and Al0.30Ga0.70N is of unknown origin, but like P1 and P2, it exhibits dislocation-related capture kinetics. The activation energy measured from the conduction band of the defects is found to increase with Al mole content, a behavior consistent with other III-V semiconductors.

Download Full-text

Deep levels and DX centers in AlxGa1−xAs/GaAs. II. Field effect deep level transient spectroscopy study

Journal of Vacuum Science & Technology B Microelectronics Processing and Phenomena ◽

10.1116/1.586397 ◽

1992 ◽

Vol 10 (1) ◽

pp. 94 ◽

Cited By ~ 6

Author(s):

N. C. Halder

Keyword(s):

Deep Level Transient Spectroscopy ◽

Field Effect ◽

Deep Level ◽

Deep Levels ◽

Spectroscopy Study ◽

Dx Centers ◽

Transient Spectroscopy

Download Full-text

Z1/2- and EH6-Center in 4H-SiC: Not Identical Defects ?

Materials Science Forum ◽

10.4028/www.scientific.net/msf.717-720.251 ◽

2012 ◽

Vol 717-720 ◽

pp. 251-254 ◽

Cited By ~ 6

Author(s):

Bernd Zippelius ◽

Alexander Glas ◽

Heiko B. Weber ◽

Gerhard Pensl ◽

Tsunenobu Kimoto ◽

...

Keyword(s):

Activation Energy ◽

Electric Field ◽

Deep Level Transient Spectroscopy ◽

Deep Level ◽

Schottky Contacts ◽

Double Peak ◽

Carbon Vacancy ◽

High Concentrations ◽

Transient Spectroscopy ◽

Dlts Spectra

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.

Download Full-text

Midgap electron traps in n-type GaAs epitaxial layers grown by the close-spaced vapor transport technique

Canadian Journal of Physics ◽

10.1139/p91-066 ◽

1991 ◽

Vol 69 (3-4) ◽

pp. 407-411 ◽

Cited By ~ 2

Author(s):

T. Bretagnon ◽

A. Jean ◽

P. Silvestre ◽

S. Bourassa ◽

R. Le Van Mao ◽

...

Keyword(s):

Deep Level Transient Spectroscopy ◽

Emission Rate ◽

Deep Level ◽

Vapor Transport ◽

Epitaxial Layers ◽

Spectroscopy Technique ◽

Electron Traps ◽

Si Doped ◽

Transient Spectroscopy ◽

Transport Technique

The deep-level transient spectroscopy technique was applied to the study of deep electron traps existing in n-type GaAs epitaxial layers that were prepared by the close-spaced vapor transport technique using three kinds of sources (semi-insulator-undoped, Zn-doped and Si-doped GaAs). Two midgap electron traps labelled ELCS1 and EL2 were observed in all layers regardless of the kind of source used. In addition, the effect of the electric field on the emission rate of ELCS1 is discussed and its identification to ETX2 and EL12 is suggested.

Download Full-text

Rapid-Thermal-Processing Induced Deep Level Traps and their Spatial Distribution in MBE GaAs

MRS Proceedings ◽

10.1557/proc-92-361 ◽

1987 ◽

Vol 92 ◽

Author(s):

Akio Kitagawa ◽

Yutaka Tokuda ◽

Akira Usami ◽

Takao Wada ◽

Hiroyuki kano

Keyword(s):

Thermal Processing ◽

Deep Level Transient Spectroscopy ◽

Molecular Beam ◽

Deep Level ◽

Rapid Thermal Processing ◽

Spatial Variations ◽

Molecular Beam Epitaxial ◽

Gaas Films ◽

Si Doped ◽

Transient Spectroscopy

ABSTRACTRapid thermal processing (RTP) using halogen lamps for a Si-doped molecular beam epitaxial (MBE) n-GaAs layers was investigated by deep level transient spectroscopy. RTP was performed at 700°C, 800°C and 900°C for 6 s. Two electron traps NI ( Ec-0.5-0.7eV) and EL2 (Ec - 0.82 eV) are produced by RTP at 800 and 900°C.The peculiar spatial variations of the Nl and EL2 concentration across the MBE GaAs films are observed. The larger concentrations of the trap N1 and EL2 are observed near the edge of the samples, and the minima of N1 and EL2 concentration lie between the center and the edge of the sample. It seems that these spatial variations of N1 and EL2 concentration are consistent with that of the thermal stress induced by RTP. Furthermore, the EL2 concentration near the edge of the sample is suppressed by the contact with the GaAs pieces on the edge around the sample during RTP.

Download Full-text

In Situ Deep Level Transient Spectroscopy of Defect Evolution in Silicon Following Ion Implantation at 80 K

MRS Proceedings ◽

10.1557/proc-532-73 ◽

1998 ◽

Vol 532 ◽

Cited By ~ 4

Author(s):

C. R. Cho ◽

R. A. Brown ◽

O. Kononchuk ◽

N. Yarykin ◽

G. Rozgonyi ◽

...

Keyword(s):

Deep Level Transient Spectroscopy ◽

Room Temperature ◽

Deep Level ◽

Temperature Range ◽

Type Silicon ◽

Defect Annealing ◽

Interstitial Defects ◽

Transient Spectroscopy ◽

Dlts Spectra

ABSTRACTThe evolution of defects in Czochralski and epitaxial p- and n-type silicon wafers following irradiation with He. Si or Ge ions at 80 K has been investigated by in situ deep level transient spectroscopy (DLTS). Defect annealing and formation reactions have been observed over the temperature range 80–350 K. In p-type silicon, new species-dependent levels are observed immediately after implantation, but these levels anneal out at or below room temperature. The wellknown divacancy and interstitial defects, usually reported after room temperature implantation, are revealed in the DLTS spectra only upon annealing at 160–200 K. In n-type silicon, vacancy-oxygen pairs are observed immediately after implantation. However, vacancy-related defects continue to form over a broad temperature range in samples implanted with Si or Ge. These observations are consistent with a model whereby vacancies and interstitials are released from defect clusters at temperatures >200 K to form divacancies and other defect pairs which are stable at room temperature.

Download Full-text