Distinct enhancement of sub-bandgap photoresponse through intermediate band in high dose implanted ZnTe:O alloys

Jing Li, Jiandong Ye*, Fangfang Ren, Dongming Tang, Yi Yang, Kun Tang, Shulin Gu, Rong Zhang, Youdou Zheng

*Corresponding author for this work

    Research output: Contribution to journalArticlepeer-review

    13 Citations (Scopus)

    Abstract

    The demand for high efficiency intermediate band (IB) solar cells is driving efforts in producing high quality IB photovoltaic materials. Here, we demonstrate ZnTe:O highly mismatched alloys synthesized by high dose ion implantation and pulsed laser melting exhibiting optically active IB states and efficient sub-gap photoresponse, as well as investigate the effect of pulsed laser melting on the structural and optical recovery in detail. The structural evolution and vibrational dynamics indicates a significant structural recovery of ZnTe:O alloys by liquid phase epitaxy during pulsed laser melting process, but laser irradiation also aggravates the segregation of Te in ZnTe:O alloys. A distinct intermediate band located at 1.8 eV above valence band is optically activated as evidenced by photoluminescence, absorption and photoresponse characteristics. The carrier dynamics indicates that carriers in the IB electronic states have a relatively long lifetime, which is beneficial for the fast separation of carriers excited by photons with sub-gap energy and thus the improved overall conversion efficiency. The reproducible capability of implantation and laser annealing at selective area enable the realization of high efficient lateral junction solar cells, which can ensure extreme light trapping and efficient charge separation.

    Original languageEnglish
    Article number44399
    JournalScientific Reports
    Volume7
    DOIs
    Publication statusPublished - 10 Mar 2017

    Fingerprint

    Dive into the research topics of 'Distinct enhancement of sub-bandgap photoresponse through intermediate band in high dose implanted ZnTe:O alloys'. Together they form a unique fingerprint.

    Cite this