Growth of PBI2 single crystals from stoichiometric and Pb excess melts

We have successfully grown high-purity and -quality PbI2 single crystals by the vertical Bridgman method. The rocking curves of four-crystal X-ray diffraction (XRD) show 120 arcsec in full-width at half-maximum (FWHM). The photoluminescence (PL) spectra at 7.8 K show the resolved intensive exciton emission line and the weak DAP emission band. The deep-level emissions are not observed. The measurement of the electrical and radiographic properties show that Leadiodide (PbI2) single crystal has a resistivity of 5×1010 Ω cm and imager lag is 8 s, respectively. In order to improve the controllability of crystal growth, PbI2 single crystals were also grown from a lead (Pb) excess PbI2 source. The experimental results show very good reproducibility. In addition, the growth models of crystal are proposed, and the growth mechanism is discussed.