Determination of activation energy for thermal regeneration of EL2 from its metastable state by thermally stimulated photocurrent measurements

It is shown that thermally stimulated photocurrent measurements provide a simple and effective method of determining the activation energy of thermal regeneration rate of EL2 from the metastable state to the normal state in undoped semi‐insulating GaAs. The thermal regeneration rate r is found to be 2.5×108 exp(−0.26 eV/kT) s−1.

Two-stage photoquenching in semi-insulating GaAs:EL2

The photoquenching of EL2 in semi‐insulating gallium arsenide is seen to be a complex process, where at low temperatures the initial slow quenching is followed by a switch to fast quenching. A possible explanation involving lattice strain mediated cooperative structural relaxation arising out of transition to the metastable state is proposed.

Si-GaAs中El2的光淬灭效应及有关深能级行为的研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

LEC半绝缘GaAs中EL2缺陷的亚稳性和光恢复效应与深能级缺陷的性质

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

半绝缘GaAs中EL2能级的EPR和光电导研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

Verification of EL2 electronic absorption effect on charge transfer in semi-insulating GaAs

The electronic absorption of EL2 centers has been clarified to be related to the electron acid hole photoionizations, and the transition from its ground state to metastable state, respectively. Under an illumination with a selected photon energy in the near infrared region, these three processes with different optical cross sections will show different kinetics against the illumination time. It has recently been shown that the photosensitivity (measured under 1.25 eV illumination) of the local vibrational mode absorption induced by some deep defect centers in SI-GaAs is a consequence of the electron and hole photoionizations of EL2. This paper directly measures the kinetics of the electronic transition associated with EL2 under 1.25 eV illumination, which implies the expected charge transfer among different charge states of the EL2 center. A calculation based on a simple rate equation model is in good agreement with the experimental results.

RELATION BETWEEN THE METASTABILITY OF EL2 AND THE PHOTOSENSITIVITY OF LOCAL VIBRATIONAL-MODES IN SEMIINSULATING GAAS

Recent infrared spectroscpic observations of local vibrational mode absorptions have revealed a number of photosensitive centers in semi-insulating GaAs. They include (OVAs) center which has three modes at 730 cm(-1) (A), 715 cm(-1) (B), and 714 cm(-1) (C), respectively, a suggested NH center related to a line at 983 cm(-1) (X(1)), and centers related to hydrogen, such as (H-O) or (H-N) bonds, corresponding to a group of peaks in the region of 2900-3500 cm(-1). The photosensitivity of various local vibration centers was observed to have similar time dependence under near-infrared illumination and was suggested to be due to their charge-state interconversion. Mainly described in this work is the effect of the 1.25-eV illumination. It is confirmed that this photoinduced kinetic process results from both electron capture and hole capture, which are closely related to the photoionization behavior and metastability of the EL2 center.

EL2光淬灭过程中光电导增强现象原因新探

于2010-11-23批量导入

Tender puentes : materiales de EL2 y Ciencias Sociales.

Los datos de ISBN y D.L. han sido tomados de los créditos del CD-ROM, en la carátula del mismo consta: 978-84-691-8422-6 y AS-07594-2008

Interculturalidad, EL2 y didáctica de L2.

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