Characterization of Defects in N-Type 6H-SiC Single Crystals by Optical Admittance Spectroscopy

ABSTRACTOptical admittance spectroscopy is a technique for measuring the conductance and capacitance of a junction under illumination as a function of the wavelength of the light and the frequency of the measuring AC signal. This technique has been applied to characterize deep defect levels in 6H-SiC:N. Nitrogen is a donor atom in 6H-SiC which substitutes for carbon in three inequivalent sites (h, k1, k2). giving rise to n-type conduction. Deep defect levels attributable to transition metal impurities have also been identified in 6H-SiC:N. We have examined persistent photoconductance in this material by optical admittance spectroscopy.

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Characterization of Defects in N-Type 6H-SiC Single Crystals by Optical Admittance Spectroscopy

MRS Proceedings ◽

10.1557/proc-325-353 ◽

1993 ◽

Vol 325 ◽

Cited By ~ 3

Author(s):

A.O. Evwaraye ◽

S.R. Smith ◽

W.C. Mitchel

Keyword(s):

Single Crystals ◽

Admittance Spectroscopy ◽

Donor Atom ◽

Deep Defect ◽

Metal Impurities ◽

Transition Metal Impurities ◽

Defect Levels ◽

First Time ◽

Type Conduction

AbstractOptical admittance spectroscopy is a technique for measuring the conductance and capacitance of a junction under illumination as a function of the wavelength of the light and the frequency of the measuring AC signal. For the first time, this technique is applied to characterize deep defect levels in 6H-SiC:N. Nitrogen is a donor atom in 6H-SiC which substitutes for carbon in three inequivalent sites (h, kl, k2). giving rise to n-type conduction. Deep defect levels attributible to transition metal impurities have been identified in 6H-SiC:N by optical admittance spectroscopy.

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gallium phosphide (GaP), defect levels associated with transition metal impurities: capture and emission data

Impurities and Defects in Group IV Elements, IV-IV and III-V Compounds. Part b: Group IV-IV and III-V Compounds. - Landolt-Börnstein - Group III Condensed Matter ◽

10.1007/10860305_62 ◽

2005 ◽

pp. 1-5

Author(s):

Keyword(s):

Transition Metal ◽

Gallium Phosphide ◽

Emission Data ◽

Metal Impurities ◽

Transition Metal Impurities ◽

Defect Levels

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gallium phosphide (GaP), defect levels associated with transition metal impurities: energy levels

Impurities and Defects in Group IV Elements, IV-IV and III-V Compounds. Part b: Group IV-IV and III-V Compounds. - Landolt-Börnstein - Group III Condensed Matter ◽

10.1007/10860305_61 ◽

2005 ◽

pp. 1-9

Author(s):

Keyword(s):

Transition Metal ◽

Gallium Phosphide ◽

Energy Levels ◽

Metal Impurities ◽

Transition Metal Impurities ◽

Defect Levels

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The Effect of Annealing on High-resistivity and Semi-insulating 4H-SiC

MRS Proceedings ◽

10.1557/proc-742-k5.16 ◽

2002 ◽

Vol 742 ◽

Cited By ~ 1

Author(s):

S. R. Smith ◽

A. O. Evwaraye ◽

W. C. Mitchel

Keyword(s):

Transition Metal ◽

Thermal Oxidation ◽

Thermal Annealing ◽

Deep Levels ◽

High Resistivity ◽

Admittance Spectroscopy ◽

Metal Impurities ◽

Transition Metal Impurities ◽

Before And After

ABSTRACTWe have examined specimens of high-resistivity, and semi-insulating, 4H-SiC before and after thermal annealing at 1600 °C, using Optical Admittance Spectroscopy. We have found enhanced ultraviolet response in most specimens. Enhanced activation of previously undetected V impurities has also been observed. Peaks believed to be attributable to complex V-related defects were greatly reduced by annealing. The annealing was in addition to a thermal oxidation at 1150 °C for 4 hours. The purpose of the oxidation was to remove surface-related deep levels known to be present in polished SiC. Transition metal impurities in these bulk specimens were quantified by SIMS. In specimens where Ti was not detected by SIMS, no further activation of Ti centers was detected by Optical Admittance Spectroscopy.

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Transition-Metal Impurity Luminescence in GaAs and its Application to Material Characterization

MRS Proceedings ◽

10.1557/proc-378-263 ◽

1995 ◽

Vol 378 ◽

Author(s):

T. Nishino

Keyword(s):

Transition Metal ◽

Near Infrared ◽

Energy Levels ◽

Local Strain ◽

Infrared Region ◽

Luminescence Line ◽

Metal Impurities ◽

Transition Metal Impurity ◽

Transition Metal Impurities

AbstractA number of sharp characteristic luminescence lines has been observed for GaAs doped with 3d transition-metal impurities in the near-infrared region, the origin being attributed to the zero-phonon intracenter transitions between the energy levels of the metal ions split by the crystal field of the GaAs lattice. It is also known that these luminescence lines are very sensitive to the surrounding field of the transition-metal impurities. The luminescence of Cr-doped GaAs has been most extensively studied, the spectrum revealing a very sharp luminescence line at 0.839 eV. In this paper we review the results on the successful applications of this Cr-related luminescence line to characterization of in-depth profiles of arsenic vacancy in thermally annealed GaAs, local strain field in In-doped GaAs and interface stress at heterostructures grown on Cr-doped GaAs substrate.

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