Thermal Histories of Defect Centers as Measured by Low Temperature Photoluminescence in n- and p-Type 4H SiC Epilayers Generated by Irradiation with 170 keV or 1 MeV Electrons

2010 ◽  
Vol 645-648 ◽  
pp. 419-422
Author(s):  
Fei Yan ◽  
Robert P. Devaty ◽  
Wolfgang J. Choyke ◽  
Katsunori Danno ◽  
Giovanni Alfieri ◽  
...  

In this paper we describe an effort to find correlations between low temperature photoluminescence spectroscopy (LTPL) and deep level transient spectroscopy (DLTS) of electron irradiated samples annealed from 25 °C to 1700 °C in 100 °C steps. We report on thermal histories of defect centers created by 170 keV and 1 MeV electron irradiation, as observed by LTPL only. The DLTS results on "twin" samples are presented in a separate paper. Our results indicate that in n-type 4H SiC there is no correlation between the Z1/Z2 center in DLTS and the L1 peak of the DI center seen in LTPL. In p-type 4H SiC we do not find a correlation between a 350 meV DLTS peak above the valence band and the LTPL L1 peak of the DI center. Consequently, we cannot find evidence for a 350 meV ground state postulated in the “Pseudo–Donor” model [3].

2017 ◽  
Vol 897 ◽  
pp. 238-241 ◽  
Author(s):  
Louise Lilja ◽  
Ildiko Farkas ◽  
Ian Booker ◽  
Jawad ul Hassan ◽  
Erik Janzén ◽  
...  

In this study we have grown thick 4H-SiC epitaxial layers with different n-type doping levels in the range 1E15 cm-3 to mid 1E18 cm-3, in order to investigate the influence on carrier lifetime. The epilayers were grown with identical growth conditions except the doping level on comparable substrates, in order to minimize the influence of other parameters than the n-type doping level. We have found a drastic decrease in carrier lifetime with increasing n-type doping level. Epilayers were further characterized with low temperature photoluminescence and deep level transient spectroscopy.


2011 ◽  
Vol 679-680 ◽  
pp. 265-268 ◽  
Author(s):  
Thanos Tsirimpis ◽  
S. Beljakova ◽  
Bernd Zippelius ◽  
Heiko B. Weber ◽  
Gerhard Pensl ◽  
...  

p-type 3C-SiC samples were implanted by iron (Fe) and investigated by means of deep level transient spectroscopy (DLTS). Corresponding argon (Ar) profiles with similar implantation damage were implanted in order to distinguish between iron-related defects and defects caused by implantation damage. Two donor-like iron-related centers were identified in p-type 3C-SiC.


2010 ◽  
Vol 645-648 ◽  
pp. 423-426 ◽  
Author(s):  
Sergey A. Reshanov ◽  
Svetlana Beljakowa ◽  
Bernd Zippelius ◽  
Gerhard Pensl ◽  
Katsunori Danno ◽  
...  

This paper comprises a systematic study of the thermal stability of defect centers observed in n- and p-type 4H-SiC by deep level transient spectroscopy (DLTS); the defects are generated by irradiation with high-energy electrons of 170 keV or 1 MeV.


2011 ◽  
Vol 679-680 ◽  
pp. 257-260 ◽  
Author(s):  
Lia Trapaidze ◽  
R. Hollweck ◽  
Svetlana Beljakowa ◽  
Bernd Zippelius ◽  
Heiko B. Weber ◽  
...  

Fe-implanted n-/p-type 4H-SiC samples were investigated by deep level transient spectroscopy (DLTS). In order to be able to separate Fe-related defect centers from defects caused by implantation damage, a corresponding Ar-profile was implanted. No Fe-related defects were observed in n-type 4H-SiC, while two Fe-related centers could be identified in p-type 4H-SiC. The electrical behavior of these centers is donor-like.


2013 ◽  
Vol 205-206 ◽  
pp. 451-456 ◽  
Author(s):  
Pavel Hazdra ◽  
Vít Záhlava ◽  
Jan Vobecký

Electronic properties of radiation damage produced in 4H-SiC by electron irradiation and its effect on electrical parameters of Junction Barrier Schottky (JBS) diodes were investigated. 4H‑SiC N‑epilayers, which formed the low‑doped N-base of JBS power diodes, were irradiated with 4.5 MeV electrons with fluences ranging from 1.5x1014 to 5x1015 cm-2. Radiation defects were then characterized by capacitance deep-level transient spectroscopy and C-V measurement. Results show that electron irradiation introduces two defect centers giving rise to acceptor levels at EC‑0.39 and EC‑0.60 eV. Introduction rate of these centers is 0.24 and 0.65 cm‑1, respectively. These radiation defects have a negligible effect on blocking and dynamic characteristics of irradiated diodes, however, the acceptor character of introduced deep levels and their high introduction rates deteriorate diode’s ON-state resistance already at fluences higher than 1x1015 cm‑2.


2005 ◽  
Vol 108-109 ◽  
pp. 279-284 ◽  
Author(s):  
O.F. Vyvenko ◽  
N.V. Bazlov ◽  
M.V. Trushin ◽  
A.A. Nadolinski ◽  
Michael Seibt ◽  
...  

Influence of annealing in molecular hydrogen as well as of treatment in hydrogen plasma (hydrogenation) on the electrical properties of NiSi2 precipitates in n- and p-type silicon has been studied by means of deep level transient spectroscopy (DLTS). Both annealing and hydrogenation gave rise to noticeable changes of the shape of the DLTS-peak and of the character of its dependence on the refilling pulse duration that according to [1] allows one to classify the electronic states of extended defects as “band-like” or “localized”. In both n- and p-type samples DLTS-peak in the initial as quenched samples showed bandlike behaviour. Annealing or hydrogenation of n-type samples converted the band-like states to the localised ones but differently shifted the DLTS-peak to higher temperatures. In p-type samples, the initial “band-like” behaviour of DLTS peak remained qualitatively unchanged after annealing or hydrogenation. A decrease of the DLTS-peak due to precipitates and the appearance of the peaks due to substitutional nickel and its complexes were found in hydrogenated p-type sample after removal of a surface layer of 10-20µm.


2010 ◽  
Vol 645-648 ◽  
pp. 759-762
Author(s):  
Koutarou Kawahara ◽  
Giovanni Alfieri ◽  
Michael Krieger ◽  
Tsunenobu Kimoto

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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