Vacancies and deep levels in electron-irradiated 6HSiC epilayers studied by positron annihilation and deep level transient spectroscopy

In this study, deep levels are investigated, which are introduced by reactive ion etching (RIE) of n-type/p-type 4H-SiC. The capacitance of as-etched p-type SiC is remarkably small due to compensation or deactivation of acceptors. These acceptors can be recovered to the initial concentration of the as-grown sample after annealing at 1000oC. However, various kinds of defects remain at a total density of ~5× 1014 cm-3 in a surface-near region from 0.3 μm to 1.0 μm even after annealing at 1000oC. The following defects are detected by Deep Level Transient Spectroscopy (DLTS): IN2 (EC – 0.35 eV), EN (EC – 1.6 eV), IP1 (EV + 0.35 eV), IP2 (HS1: EV + 0.39 eV), IP4 (HK0: EV + 0.72 eV), IP5 (EV + 0.75 eV), IP7 (EV + 1.3 eV), and EP (EV + 1.4 eV). These defects generated by RIE can be significantly reduced by thermal oxidation and subsequent annealing at 1400oC.

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Characterization of deep levels in high electron mobility transistor by conductance deep level transient spectroscopy

Materials Science and Engineering C ◽

10.1016/j.msec.2007.10.068 ◽

2008 ◽

Vol 28 (5-6) ◽

pp. 787-790 ◽

Cited By ~ 13

Author(s):

M. Gassoumi ◽

J.M. Bluet ◽

G. Guillot ◽

C. Gaquière ◽

H. Maaref

Keyword(s):

Electron Mobility ◽

Deep Level Transient Spectroscopy ◽

Deep Level ◽

High Electron Mobility Transistor ◽

Deep Levels ◽

High Electron ◽

High Electron Mobility ◽

Transient Spectroscopy

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Point Defects in Gallium Arsenide Characterized by Positron Annihilation Spectroscopy and Deep Level Transient Spectroscopy

MRS Proceedings ◽

10.1557/proc-373-517 ◽

1994 ◽

Vol 373 ◽

Cited By ~ 2

Author(s):

R. Mih ◽

R. Gronsky

Keyword(s):

Gallium Arsenide ◽

Positron Annihilation ◽

Deep Level Transient Spectroscopy ◽

Deep Level ◽

Czochralski Method ◽

Positron Annihilation Spectroscopy ◽

Crystallographic Data ◽

Electrical Measurements ◽

Vacancy Defects ◽

Transient Spectroscopy

AbstractPositron annihilation lifetime spectroscopy (PALS) is a unique technique for detection of vacancy related defects in both as-grown and irradiated materials. We present a systematic study of vacancy defects in stoichiometrically controlled p-type Gallium Arsenide grown by the Hot- Wall Czochralski method. Microstructural information based on PALS, was correlated to crystallographic data and electrical measurements. Vacancies were detected and compared to electrical levels detected by deep level transient spectroscopy and stoichiometry based on crystallographic data.

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Process-Induced Defects in High-Purity GaAs

MRS Proceedings ◽

10.1557/proc-14-283 ◽

1982 ◽

Vol 14 ◽

Cited By ~ 1

Author(s):

P. H. Campbell ◽

O. Aina ◽

B. J. Baliga ◽

R. Ehle

Keyword(s):

High Temperature ◽

High Purity ◽

Deep Level Transient Spectroscopy ◽

Deep Level ◽

Deep Levels ◽

Schottky Contacts ◽

High Temperature Annealing ◽

Order Of Magnitude ◽

Transient Spectroscopy ◽

Induced Defects

ABSTRACTHigh temperature annealing of Si 3 N4 and SiO2 capped high purity LPE GaAs is shown to result in a reduction in the surface carrier concentration by about an order of magnitude. Au Schottky contacts made on the annealed samples were found to have severely degraded breakdown characteristics. Using deep level transient spectroscopy, deep levels at EC–.58eV, EC–.785eV were detected in the SiO2, capped samples and EC–.62eV, EC–.728eV in the Si3N4 capped Samples while none was detected in the unannealed samples.The electrical degradations are explained in terms of compensation mechanisns and depletion layer recombination-generation currents due to the deep levels.

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