Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-23T17:48:11.523Z Has data issue: false hasContentIssue false

Dependence of the Sn0/2+ charge state on the Fermi level in semi-insulating CdTe

Published online by Cambridge University Press:  31 January 2011

V. Babentsov
Affiliation:
Institute for Semiconductor Physics, Kiev 03028, Ukraine
J. Franc*
Affiliation:
Charles University, Faculty of Mathematics and Physics, Institute of Physics, Prague CZ 121 16, Czech Republic
H. Elhadidy
Affiliation:
Charles University, Faculty of Mathematics and Physics, Institute of Physics, Prague CZ 121 16, Czech Republic
A. Fauler
Affiliation:
Materialforschungszentrum, Freiburg D-79104, Germany
M. Fiederle
Affiliation:
Materialforschungszentrum, Freiburg D-79104, Germany
R.B. James
Affiliation:
Energy, Environment and National Security Directorate, Brookhaven National Laboratory, Upton, New York 11973
*
a)Address all correspondence to this author. e-mail: [email protected]
Get access

Abstract

We explored the growth and characteristics of CdTe doped with Sn to heighten our understanding of the role of deep levels on electrical compensation and trapping. We demonstrated, for the first time, the strong dependence of the SnCd charge state on the Fermi-level variation (2–3kT) in high-resistivity CdTe. The concentration of deep traps for electrons was determined by the number of doubly positively charged Sn2+ atoms. Thermoelectric-effect spectroscopy and photovoltage measurements revealed the conversion of the SnCd defect from the electron SnCd2+ trap to the hole SnCd0 trap. The results agree well with the existence of a negative U-center in the SnCd0/2+ defect. We also showed that the neutral Sn defect is responsible for the near midgap C-band → bound hole radiative transitions band with a maximum at 0.76 eV.

Type
Articles
Copyright
Copyright © Materials Research Society 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1Schlesinger, T.E., Toney, J.E., Yoon, H., Lee, E.Y., Brunett, B.A., Franks, L.James, R.B.: Cadmium zinc telluride and its use as a nuclear radiation detector material. Mater. Sci. Eng., R 32, 103 2001CrossRefGoogle Scholar
2Shcherbin, K., Volkov, V., Rudenko, V., Odoulov, S., Borshch, A., Zakharuk, Z.Rarenko, I.: Photorefractive properties of CdTe:Sn. Phys. Status Solidi A 183, 337 20013.0.CO;2-N>CrossRefGoogle Scholar
3Awadalla, S.A., Hunt, A.W., Lynn, K.G., Glass, H., Szeles, C.Wei, S-H.: Isoelectronic oxygen-related defect in CdTe crystals investigated using thermoelectric effect spectroscopy. Phys. Rev. B 69, 075210 2004CrossRefGoogle Scholar
4Krsmanovic, N., Lynn, K.G., Weber, M.H., Tjossem, R., Gessmann, Th., Szeles, C., Eissler, E.E., Flint, J.P.Glass, H.L.: Electrical compensation in CdTe and Cd0.9Zn0.1Te by intrinsic defects. Phys. Rev. B 62, R16279 2000CrossRefGoogle Scholar
5Soundararajan, R., Lynn, K.G., Awadallah, S., Szeles, C.Wei, S.H.: Study of defect levels in CdTe using thermoelectric effect spectroscopy. J. Electron. Mater. 35, 1333 2006CrossRefGoogle Scholar
6Rzepka, E., Marfaing, Y., Cuniot, M.Triboulet, R.: Deep centres for optical processing in CdTe. Mater. Sci. Eng., B 16, 262 1993CrossRefGoogle Scholar
7Becker, U., Rudolph, P., Boyn, R., Wienecke, M.Utke, I.: Characterization of p-type CdTe Bridgman crystals by infrared extinction spectra. Phys. Status Solidi A 120, 653 1990CrossRefGoogle Scholar
8Rudolph, P., Schröter, H., Rinas, U., Zimmermann, H.Boyn, R.: Control of composition and substitutional acceptor density during crystal growth of CdTe. Adv. Mater. Opt. Electron. 3, 289 1994CrossRefGoogle Scholar
9Fiederle, M., Fauler, A., Konrath, J., Babentsov, V., Franc, J.James, R.B.: Comparison of undoped and doped high resistivity CdTe and (Cd,Zn)Te detector crystals. IEEE Trans. Nucl. Sci. 51, 1864 2004CrossRefGoogle Scholar
10Franc, J., Elhadidy, H., Babentsov, V., Fauler, A.Fiederle, M.: Comparative study of vertical gradient freeze grown CdTe with variable Sn concentration. J. Mater. Res. 21, 1025 2006CrossRefGoogle Scholar
11Franc, J., Fiederle, M., Babentsov, V., Fauler, A., Benz, K.W.James, R.B.: Defect structure of Sn-doped CdTe. J. Electron. Mater. 32, 772 2003CrossRefGoogle Scholar
12Turkevych, I., Grill, R., Franc, J., Höschl, P., Belas, E., Moravec, P., Fiederle, M.Benz, K.W.: Preparation of semi-insulating CdTe doped with group IV elements by post growth annealing. Cryst. Res. Technol. 38, 288 2003CrossRefGoogle Scholar
13Santic, B.Desnica, U.V.: Thermoelectric effect spectroscopy of deep levels: Application to semi-insulating GaAs. Appl. Phys. Lett. 56, 2636 1990CrossRefGoogle Scholar
14Kronik, L.Shapira, Y.: Surface photovoltage phenomena: Theory, experiment and applications. Surf. Sci. Rep. 37, 1 1999CrossRefGoogle Scholar
15Stibal, R., Windscheif, J.Jantz, W.: Contactless evaluation of semiinsulating GaAs wafer resistivity using time-dependent charge measurements. Semicond. Sci. Technol. 6, 995 1991CrossRefGoogle Scholar
16Astles, M.G.: EMIS Datareviews Series, 10 Ed. INSPEC, London,,1994 494–500Google Scholar
17Babentsov, V., Corregidor, V., Castaño, J.L., Diéguez, E., Fiederle, M., Feltgen, T.Benz, K.: Compensation in semi-intrinsic CdTe based materials. Proc. SPIE: Int. Soc. Opt. Eng. 4355, 238 2001CrossRefGoogle Scholar
18Jantsch, W.Hendorfer, G.: Characterization of deep levels in CdTe by photo-EPR and related techniques. J. Cryst. Growth 101, 404 1990CrossRefGoogle Scholar
19Lee, E.Y., Brunett, B.A., Olsen, R.W., Van Scyoc, J.M. III, Hermon, H.James, R.B.: Detection of electron and hole traps in CdZnTe radiation detectors by thermoelectric emission spectroscopy and thermally stimulated conductivity. Proc. SPIE: Int. Soc. Opt. Eng. 3446, 40 1998CrossRefGoogle Scholar
20Lee, E.Y., James, R.B., Olsen, R.W.Hermon, H.: Compensation and trapping in CdZnTe radiation detectors studied by thermoelectric emission spectroscopy, thermally stimulated conductivity, and current-voltage measurements. J. Electron. Mater. 28, 766 1999CrossRefGoogle Scholar
21Awadalla, S.A., Hunt, A.W., Tjossem, R.B., Lynn, K.G., Szeles, Cs.Bliss, M.: Evidence for dislocations or related defects present in CdTe and Cd1–xZnxTe crystals. Proc. SPIE: Int. Soc. Opt. Eng. 4507, 264 2001CrossRefGoogle Scholar
22Franc, J., Grill, R., Kubát, J., Hlídek, P., Belas, E., Moravec, P.Höschl, P.: Influence of space charge on Lux-Ampere characteristics of high-resistivity CdTe. J. Electron. Mater. 35, 988 2006CrossRefGoogle Scholar
23Elhadidy, H., Franc, J., Moravec, P., Höschl, P.Fiederle, M.: Deep-level defects in CdTe materials studied by thermoelectric effect spectroscopy and photo-induced current transient spectroscopy. Semicond. Sci. Technol. 22, 537 2007CrossRefGoogle Scholar
24Jaffe, J.E.: Computational study of Ge and Sn doping of CdTe. J. Appl. Phys. 99, 033704 2006CrossRefGoogle Scholar
25Adler, D.Yoffa, E.J.: Electronic structure of amorphous semiconductors. Phys. Rev. Lett. 36, 1197 1976CrossRefGoogle Scholar
26Fiederle, M., Babentsov, V., Fauler, A., Witte, W., Benz, K.W.James, R.B.: Semi-insulating cadmium telluride at low impurity concentrations. J. Mater. Res. 19, 405 2004CrossRefGoogle Scholar