Deep electron states and persistent photoconductivity in Al-doped ZnS_1-xTex grown by molecular beam epitaxy
Abstract
In this study capacitance-voltage(C-V), photoluminescence(PL), and deep level transient spectroscopy(DLTS) techniques were used to investigate deep electron states in n-type Al-doped ZnS_1-xTex epilayers grown by molecular beam epitaxy(MBE). The PL results indicate that some of Al atoms form nonoradiative deep traps. Deep level transient Fourier spectroscopy(DLTFS) spectra of the Al doped ZnS_1-xTex (x=0, 0.017, 0.04, and 0.046, respectively) epilayers reveal that Al doping leads to the formation of two electron traps at 0.21 and 0.39eV below the conduction band, and Te is also involved in the formation of electron trap. The persistent photoconductivity(PPC) behavior was observed not only at low temperature but also at room temperature. It is suggested that the metastable centers related to Al at 0.21 and 0.39eV below the conduction band are responsible for the PPC effect in n-type Al-doped ZnS_1-xTe_x.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 1998
- Bibcode:
- 1998APS..MAR.S2312M