摘要
利用垂直两温区透明油浴炉,采用升华法成功生长了α-HgI2单晶体。通过对比不同生长阶段晶体生长界面,观察到HgI2晶体在气相生长中存在界面形貌转变。晶体生长初期的生长面呈棱面,然后逐渐转变为圆滑界面。利用XRD、透射光谱以及I-V测试对所生长晶体的性能进行了表征。XRD结果表明所生长的晶体为单相的α-HgI2晶体,晶体的生长方向为[001]。紫外-可见-近红外透过光谱分析发现,HgI2晶体的截至波长为580 nm,对应的禁带宽度为2.12 eV,近红外区内透过率约为45%。由于空穴的俘获及陷阱能级作用,在2307.5 nm和1731.4 nm处产生了两个明显的吸收峰。所生长的α-HgI2晶体电阻率约为1011Ω.cm,满足制作核辐射探测器的要求。
α-HgI2 single crystal was grown by vapor sublimation method within a vertical transparent twozones growth changes furnace. In the primary growth stage, HgI2 shows a faceted growth interface, whidh finally into the spherical one due to the high thermal resistance of HgI2. XRD, UV-VIS-IR spectrum and I-V analysis were used to characterize the properties of the as-grown crystal. The results of XRD show that the as-grown crystal is a single α-HgI2 phase with the growth direction of [ 001 ]. The UV-VIS-IR spectrum indicates that the energy gap of α-HgI2 is about 2.12 eV, corresponding to the wavelength of 580 nm. Near-infrared transmittance of HgI2 is about 45%. Two absorption peaks were observed at the wavelength of 2307.5 nm and 1731.4 nm due to the absorption of the cavity and trap levels. The electrical resistivity of the wafers was determined by I-V characteristic to be about 10^11Ω·cm.
出处
《人工晶体学报》
EI
CAS
CSCD
北大核心
2008年第4期795-799,共5页
Journal of Synthetic Crystals
