ABSTRACT In this work, a tungsten disulphide or WS2 based heterojunction photodetector device is fabricated on top of Si substrate by simple drop casting. Raman shifts are observed at 350.16 and 419.36 cm−1, confirming the successful growth of the WS2 and the non-stoichiometric WS2 layers which are verified by energy-dispersive X-ray (EDX) spectroscopy. The device is characterized for its optoelectronic properties in the ultraviolet (UV) range of 405 nm. Current–voltage (I–V) measurement is performed to obtain the I–V curves of the photodiode under laser illumination at 30.219, 56.335, 80.457, 106.998 and 129.28 mW.cm−2. The photocurrent is found to be highly dependent on the laser power. The fabricated device has a high responsivity of 145.52 mA/W and a high detectivity of 1.248 × 1011 Jones for an incident laser power density of 129.28 mW.cm−2. These observed results are promising and indicate the viability of the proposed design for optoelectronic applications.

中文翻译：

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基于滴铸法生长的二硫化钨薄膜的 405 nm 紫外光电探测器

摘要 在这项工作中，基于二硫化钨或 WS2 的异质结光电探测器器件是通过简单的滴铸法在 Si 衬底上制造的。在 350.16 和 419.36 cm-1 处观察到拉曼位移，证实了 WS2 和非化学计量 WS2 层的成功生长，这通过能量色散 X 射线 (EDX) 光谱进行了验证。该器件的特点是其在 405 nm 紫外线 (UV) 范围内的光电特性。执行电流-电压 (I-V) 测量以获得在 30.219、56.335、80.457、106.998 和 129.28 mW.cm-2 激光照射下光电二极管的 I-V 曲线。发现光电流高度依赖于激光功率。制造的器件具有 145.52 mA/W 的高响应度和 1.248 × 1011 Jones 的高探测率，入射激光功率密度为 129.28 mW.cm-2。