Center for Spintronics and Quantum Systems, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China.
ACS Appl Mater Interfaces. 2023 Jun 14;15(23):28267-28276. doi: 10.1021/acsami.3c05902. Epub 2023 Jun 1.
The semimetal-based photodetector possesses the intrinsic advantage of high response speed, low power consumption, and wide-range photoresponse. Here, we report the synthesis and application of 1 inch wafer-scale polycrystalline few layer 1T'-MoTe on the SiO/Si substrate by employing a modified chemical vapor deposition method of predeposition of precursors. A continuous film with seamlessly stitched micrometer scale grains has been realized, and the pure 1T' phase was confirmed by Raman spectroscopy. An asymmetric metal electrode photodetector device of Pd-MoTe-Au was designed and fabricated by using shadow mask-assisted UHV deposition. By measuring the self-powered photocurrent under the illumination of Xe lamp, we show that the device is sensitive to a wide spectra range (λ = 320-1200 nm) while maintaining high performance of the ON/OFF ratio (∼10), responsivity (1.2 A/W), and specific detectivity (7.68 × 10 Jones). Under 450, 648, and 850 nm pulsed laser illumination, the response time achieves tens of microsecond scale. The device shows polarized photoresponse as well. Our work may promote the potential application of a self-powered high-performance photodetector based on 1T'-MoTe.
基于半导体的光电探测器具有固有优势，包括高速响应、低功耗和宽光谱响应。在这里，我们通过采用前驱物预沉积的改进化学气相沉积方法，报告了在 SiO2/Si 衬底上合成和应用 1 英寸晶圆级多晶少层 1T'-MoTe2 的情况。实现了具有无缝拼接微米级晶粒的连续薄膜，并通过拉曼光谱证实了纯 1T'相。通过使用掩模辅助超高真空沉积设计并制造了 Pd-MoTe2-Au 不对称金属电极光电探测器器件。通过测量 Xe 灯照射下的自供电光电流，我们表明该器件对宽光谱范围（λ=320-1200nm）敏感，同时保持高 ON/OFF 比（约 10）、响应度（1.2A/W）和比探测率（7.68×109Jones）的性能。在 450、648 和 850nm 脉冲激光照射下，响应时间达到数十微秒级。该器件还表现出偏振光响应。我们的工作可能会促进基于 1T'-MoTe2 的自供电高性能光电探测器的潜在应用。
