Abstract
The relaxation dynamics of photoexcited carriers of CdTe is vital toward its applications in high-performance optoelectrical devices. In this paper, the dependences of transient drift velocities of photoexcited electrons in bulk CdTe on photoexcitation conditions such as the pump intensity and photoexcitation wavelengths, temperature and externally applied electric field, are systematically investigated by the ensemble Monte Carlo method (EMC). The main scattering mechanisms including nonelastic deformation potential acoustic phonon, deformation potential optical phonon scattering, ionized impurity (II) scattering, and polar optical phonon scattering events, the effects of nonequilibrium phonons, and the Pauli exclusion principle are considered in EMC. The velocity overshoot phenomenon is only found to arise at a low temperature (100 K), with a longer photoexcitation wavelength (640 nm) and under a higher electric field (> 50 kV/cm). The effect of nonequilibrium phonons on electron drift velocity is found to be dependent on the photoexcited carrier density. Our findings may be useful for designing novel CdTe-based optoelectronic devices, which employ nonequilibrium photoexcited carriers to improve the performance.
Similar content being viewed by others
Data availability
Enquiries about data availability should be directed to the authors.
References
Gorai, P., Krasikov, D., Grover, S., Xiong, G., Metzger, W., Stevanovic, V.: A search for new back contacts for CdTe solar cells. Sci. Adv. 9, 1–12 (2023)
Ščajev, P., Mekys, A., Subačius, L., Stanionytė, S., Kuciauskas, D., Lynn, K., Swain, S.: Impact of dopant-induced band tails on optical spectra, charge carrier transport, and dynamics in single-crystal CdTe. Sci. Rep. 12, 12851 (2022)
Rogalski, A.: Infrared detectors: an overview. Infrared Phys. Technol. 43, 187–210 (2002)
Sordo, S., Abbene, L., Caroli, E., Mancini, A., Zappettini, A., Ubertini, P.: Progress in the development of CdTe and CdZnTe semiconductor radiation detectors for astrophysical and medical applications. Sensors 9, 3491–3526 (2009)
Chenault, D., Chipman, R., Lu, S.: Electro-optic coefficient spectrum of cadmium telluride. Appl. Opt. 33, 7382–7389 (1994)
Hu, G., Li, B., Li, H., Cao, H., Ren, Z., Zhao, D., Li, W., Wu, L., Zhang, J.: Study of ultrafast photocarrier dynamics in polycrystalline CdTe films under low illumination. Sol. Energy Mater. Sol. Cells 247, 111925 (2022)
Djurberg, V., Majdi, S., Suntornwipat, N., Isberg, J.: Investigation of photoexcitation energy impact on electron mobility in single crystalline CdTe. Material 14, 4202 (2021)
Desai, H.N., Patel, P.B., Dhimmar, J.M., Modi, B.P.: Approaching new photo-electrics: CdTe nano-crystallite thin film. Solid State Commun. 313, 113910 (2020)
Sun, H., Ma, H., Leng, J.: Femtosecond pump probe reflectivity spectra in CdTe and GaAs crystals at room temperature. Materials 13, 242 (2020)
Chen, Y., Shu, T., Lai, T., Wu, H.: Excitation-density and excess-energy dependence of ultrafast dynamics of photoexcited carriers in intrinsic bulk CdTe. Results Phys. 31, 105047 (2021)
Zhong, Y., Ostach, D., Scholz, M., Epp, S.W., Techert, S., Schlichting, I., Ullrich, J., Krasniqi, F.S.: Hot carrier relaxation in CdTe via phonon–plasmon modes. J. Phys. Condens. Matter 29, 095701 (2017)
He, X., Punpongjareorn, N., Wu, C., Davydov, I., Yang, D.: Ultrafast carrier dynamics of CdTe: surface effects. J. Phys. Chem. C 120, 9350 (2016)
Ma, H., Jin, Z., Ma, G., Liu, W., Tang, S.: Photon energy and carrier density dependence of spin dynamics in bulk CdTe crystal at room temperature. Appl. Phys. Lett. 94, 241112 (2009)
Jyegal, J.: Velocity overshoot decay mechanisms in compound semiconductor field-effect transistors with a submicron characteristic length. AIP Adv. 5, 067118 (2015)
The, N., Hieu, H.: Investigation of velocity overshoot behavior in pin GaAs semiconductor: the contribution of internal electric field. Phys. Lett. A 383, 2314–2317 (2019)
Son, J., Sha, W., Kim, J., Norris, T.B., Whitaker, J.F., Mourou, G.A.: Transient velocity overshoot dynamics in GaAs for electric fields ≤ 200 kV/cm. Appl. Phys. Lett. 63, 923–925 (1993)
Fonthal, G., Tirado-Mejia, L., Hurtado, J., Calderon, H., Mendoza-Alvarezc, J.G.: Temperature dependence of the band gap energy of crystalline CdTe. J. Phys. Chem. Solids 61, 579–583 (2000)
Acoboni, C.J., Lugli, P.: The Monte Carlo Method for Semiconductor Device Simulation, 1st edn. Springer, Wien (1989)
Prajapati, J., Bharadwaj, M., Chatterjee, A., Bhattacharjee, R.: Magnetic field-assisted radiation enhancement from a large aperture photoconductive antenna. IEEE Trans. Microw. Theory Tech. 66, 678–687 (2018)
Yang, J., Shi, L., Wang, L., Wei, S.: Non-radiative carrier recombination enhanced by two level process: a first-principles study. Sci. Rep. 6, 21712 (2016)
MickeviEius, R., Reklaitis, A.: Electron intervalley scattering in gallium arsenide. Second. Sci. Technol. 5, 805–812 (1990)
Lundstrom, M.: Fundamentals of carrier transport, 2nd edn. Cambridge University Press (2000)
Mickevicius, R., Reklaitis, A.: Monte Carlo study of nonequilibrium phonon effects in GaAs. Solid State Commun. 64, 1305–1308 (1987)
Lugli, P., Ferry, D.: Degeneracy in the ensemble Monte Carlo method for high-field transport in semiconductors. IEEE Trans. Electron Devices 32, 2431 (1985)
Zhong, Qi., Dai, Z., Liu, J., Zhao, Y., Meng, S.: The excellent TE performance of photoelectric material CdSe along with a study of Zn(Cd)Se and Zn(Cd)Te based on first-principles. RSC Adv. 9, 25471 (2019)
Reklaitis, A.: Nonequilibrium optical phonon effect on high-field electron transport in InN. J. Appl. Phys. 112, 093706 (2012)
Margik, J., Kral, K.: Effect of Pauli Principle on transport properties of some crystalline compound semiconductors. Czech. J. Phys. B 35, 1180 (1985)
Yadav, D., Pauly, F., Trushin, M.: Charge-carrier thermalization in bulk and monolayer CdTe from first principles. Phys. Rev. B 103, 125113 (2021)
Reklaitis, A., Krotkus, A., Grigaliunaite, G.: Enhanced drift velocity of photoelectrons in a semiconductor with ultrafast carrier recombination. Semicond. Sci. Technol. 14, 945–947 (1999)
Acknowledgements
This work is supported by Science and Technology Program of Guangzhou, China (Grant No. 201804010444).
Funding
Funding for this study was received from the Science and Technology Program of Guangzhou, China, No. 201804010444.
Author information
Authors and Affiliations
Contributions
All the aspects of this work are completed by Dongfeng Liu.
Corresponding author
Ethics declarations
Conflict of interest
The authors declare no competing interests.
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Liu, D. Transient drift velocity of photoexcited electrons in CdTe. J Comput Electron (2024). https://doi.org/10.1007/s10825-024-02165-6
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s10825-024-02165-6