Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, United States.
Inorg Chem. 2013 Jun 17;52(12):7045-50. doi: 10.1021/ic401086r. Epub 2013 May 28.
We investigated an antimony chalcohalide compound, SbSeI, as a potential semiconductor material for X-ray and γ-ray detection. SbSeI has a wide band gap of 1.70 eV with a density of 5.80 g/cm(3), and it crystallizes in the orthorhombic Pnma space group with a one-dimensional chain structure comprised of infinite zigzag chains of dimers [Sb2Se4I8]n running along the crystallographic b axis. In this study, we investigate conditions for vertical Bridgman crystal growth using combinations of the peak temperature and temperature gradients as well as translation rate set in a three-zone furnace. SbSeI samples grown at 495 °C peak temperature and 19 °C/cm temperature gradient with 2.5 mm/h translation rate produced a single phase of columnar needlelike crystals aligned along the translational direction of the growth. The ingot sample exhibited an n-type semiconductor with resistivity of ∼10(8) Ω·cm. Photoconductivity measurements on these specimens allowed us to determine mobility-lifetime (μτ) products for electron and hole carriers that were found to be of similar order of magnitude (∼10(-4) cm(2)/V). Further, the SbSeI ingot with well-aligned, one-dimensional columnar needlelike crystals shows an appreciable response of Ag Kα X-ray.
我们研究了一种锑碲卤化物化合物 SbSeI，它是一种有前途的 X 射线和 γ 射线检测半导体材料。SbSeI 的带隙为 1.70 eV，密度为 5.80 g/cm(3)，它在正交 Pnma 空间群中结晶，具有由无限锯齿链 [Sb2Se4I8]n 组成的一维链结构，沿晶体学 b 轴延伸。在这项研究中，我们通过在三区炉中设定的峰值温度和温度梯度以及平移率的组合，研究了垂直布里奇曼晶体生长的条件。在 495 °C 的峰值温度和 19 °C/cm 的温度梯度下，以 2.5 mm/h 的平移率生长的 SbSeI 样品产生了单一的柱状针状晶体相，沿生长的平移方向排列。锭样品表现出 n 型半导体特性，电阻率约为 10(8) Ω·cm。对这些样品的光电导测量使我们能够确定电子和空穴载流子的迁移率-寿命（μτ）乘积，发现它们具有相似的数量级（约 10(-4) cm(2)/V）。此外，具有良好取向的一维柱状针状晶体的 SbSeI 锭在 Ag Kα X 射线下表现出明显的响应。
