In this study, the TiO2/p-Si and Gd:TiO2/p-Si heterojunctions were fabricated by sol–gel method. The UV–Vis spectroscopy was performed to evaluate optical characteristics of TiO2 and Gd:TiO2 thin films. It was observed that the optical band gap, transmittance, extinction coefficient and optical dielectric constants of TiO2 thin film were increased with Gd content. The electrical features of the heterojunction diodes were analyzed and compared by conventional I–V measurements under dark condition. With the Gd doping, the ideality factor of TiO2/p-Si diode decreased from 8.97 to 3.87 and rectification ratio increased from 1.59 × 103 to 1.45 × 106. The serial resistance of diodes was calculated by both Norde and Cheung methods. The high series resistance value and high dark current of the TiO2/p-Si diode have been successfully surmounted with the Gd doping. Moreover, the photovoltaic properties of the Gd:TiO2/p-Si photodiode were studied under various illumination intensities. It has been shown that the Gd:TiO2/p-Si diode can be utilized as a photosensor due to its reaction to light.

中文翻译：

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通过钆掺杂增强 TiO2/p-Si 异质结二极管的电性能

在这项研究中，TiO2/p-Si 和 Gd:TiO2/p-Si 异质结是通过溶胶-凝胶法制备的。使用紫外-可见光谱来评估 TiO2 和 Gd:TiO2 薄膜的光学特性。观察到TiO2薄膜的光学带隙、透射率、消光系数和光学介电常数随着Gd含量的增加而增加。在黑暗条件下，通过传统的 I-V 测量分析和比较异质结二极管的电气特性。随着 Gd 掺杂，TiO2/p-Si 二极管的理想因子从 8.97 降低到 3.87，整流比从 1.59 × 103 增加到 1.45 × 106。二极管的串联电阻通过 Norde 和 Cheung 方法计算。Gd掺杂已经成功克服了TiO2/p-Si二极管的高串联电阻值和高暗电流。此外，研究了 Gd:TiO2/p-Si 光电二极管在不同光照强度下的光伏特性。已经表明 Gd:TiO2/p-Si 二极管由于其对光的反应而可用作光电传感器。