In this article, we present a simple and low-cost experimental setup for thermoelectric effect measurements of thin film materials near room temperature, which can be used to determine their conductivity types. Bi₂Te₃ and Sb₂Te₃ thin films grown by the molecular beam epitaxy technique were used as the tested samples. Their Seebeck coefficients were determined to be $(-141\pm 1)\,{\mathrm{\mu V/K}}$ and $(39\pm 2)\,{\mathrm{\mu V/K}}$ , respectively, confirming that the former is an n-type material and the latter is a p-type material. A heterostructure composed of Sb₂Te₃ and Bi₂Te₃ was characterized by electrical transport measurements. Data fitting was carried out for its current–voltage characteristics with the Shockley diode model and a real diode model proposed by Cataldo et al., and some physical parameters of the heterostructure were extracted, including its ideality factor and saturation current. Based on its rectifying current–voltage behavior, we confirm that the aforementioned heterostructure is a p-n junction, which echoes the contrast in the conductivity types of Sb₂Te₃ and Bi₂Te₃ as determined by the thermoelectric effect measurements.

中文翻译：

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用于确定薄膜材料导电类型的简单热电效应设置

在本文中，我们提出了一种简单且低成本的实验装置，用于对接近室温的薄膜材料进行热电效应测量，可用于确定它们的导电类型。通过分子束外延技术生长的Bi ₂ Te ₃和Sb ₂ Te ₃薄膜被用作测试样品。他们的塞贝克系数被确定为 $(-141\pm 1)\,{\mathrm{\mu V/K}}$ 和 $(39\pm 2)\,{\mathrm{\mu V/K}}$ ，分别确认前者为n型材料，后者为p型材料。由Sb ₂ Te ₃和Bi ₂ Te ₃组成的异质结构通过电传输测量表征。使用肖克利二极管模型和 Cataldo 提出的真实二极管模型对其电流-电压特性进行数据拟合等。，并提取了异质结构的一些物理参数，包括其理想因子和饱和电流。基于其整流电流-电压行为，我们确认上述异质结构是 pn 结，这与热电效应测量确定的 Sb ₂ Te ₃和 Bi ₂ Te ₃的导电类型的对比相呼应。