摘要
通过改进的垂直布里奇曼法(MVB),引入铟(In)元素掺杂,在Te过量条件下生长CdTe:In和CdZnTe:In晶体,对比研究了两种晶体的质量、电学性能与光学性能之间的关联.结果表明,晶体的结晶质量和电学性能优劣可通过晶体光学性能结果给出定性评价.一方面,CdZnTe:In晶体的红外透过率高,达到了63%,接近于理论值,同时晶体中富Te相的形貌与尺寸相似、分布均匀,故CdZnTe:In晶体的结晶质量较好,相应的晶体电阻率达到了10~9数量级,电学性能较好.另一方面,CdZnTe:In晶体的光致发光谱中出现的(D~0,X)峰较尖锐,半峰宽约为8.6 meV,且谱峰中相邻的FE峰清晰可见,这表明CdZnTe:In晶体中Te夹杂/沉淀数量少,晶体具有高阻特性.
In this paper, In-doped CdTe(CdTe:In) and In-doped CdZnTe(CdZnTe:In) crystals were grown by the modified vertical Bridgman(MVB) method under Te-rich conditions, and their correlations between crystal quality, electrical properties and optical properties were discussed. The results show that the crystal quality and electrical properties of CdTe:In and CdZnTe:In can be qualitatively evaluated by their optical properties. On the one hand, the infrared transmittance of CdZnTe:In crystal was high to 63%, which is close to the theoretical value. In the meantime, the Te-rich phase of CdZnTe:In crystal was distributed uniformly, and its morphology and size were also similar. As a consequnce the crystal quality of CdZnTe:In should be well. Furthermore, its corresponding resistivity was up to 10~9 orders of magnitude, which indicates a good electrical performance of CdZnTe:In crystal. On the other hand, the(D~0,X) peak in PL spectrum of CdZnTe:In crystal was sharp and its FWHM reached to 8.6 meV, accompanied with a clearly visible FE peak. It indicated a small number of Te inclusions/precipitation in CdZnTe:In crystal to obtain the high-resistivity performance.
引文
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