| 摘要: | 本論文探討低溫電子束蒸鍍技術在沉積金屬於二硫化鉬（MoS2）基底上對蕭特基二極體性能的影響。MoS2因其優異的電子特性和可調控的能隙，成為現代電子元件中的潛力材料。然而，傳統製備的MoS2蕭特基二極體常面臨反向漏電流過高、整流比低及理想因子不佳等問題。
在本研究中，我們使用低溫電子束蒸鍍技術，在單層MoS2上沉積金屬，並分析了低溫沉積對蕭特基能障高度以及二極體光電性能的影響。研究結果顯示，隨著Au沉積溫度的降低，對MoS2表面的熱損傷顯著減少，並且實現了較大的蕭特基能障。當閘極電壓為0 V且Vds = ±5 V時，在298 K、173 K和77 K下沉積的二極體整流比分別為1.7 x 10²、5.8 x 10²和9.6 x 10³。而在閘極電壓為20 V、77 K條件下沉積的二極體，整流比可達到10⁴，顯示出低溫沉積技術能有效抑制反向電流。光電測試結果表明，在光照條件下，三組元件的電流變化均超過10³ %，且沉積溫度越低，光反應越顯著。這表明低溫沉積技術不僅提升了元件的電學性能，還具有優異的光電反應能力。
本研究結果顯示，低溫電子束蒸鍍技術在減少表面損傷、提升蕭特基能障及抑制反向電流方面具有明顯優勢，並為基於二維材料的蕭特基二極體提供了潛在的發展方向。
;This thesis explores the impact of low-temperature electron beam evaporation（EBE） deposition of metals on the performance of molybdenum disulfide（MoS2）based Schottky diodes. Due to its excellent electronic properties and tunable bandgap, MoS2 has emerged as a promising material for modern electronic devices. However, traditionally fabricated MoS2 Schottky diodes often encounter issues such as high reverse leakage current, low rectifying ratio, and poor ideality factor.
In this study, we employed low-temperature EBE to deposit metals onto monolayer MoS2 and analyzed the impact of low-temperature deposition on the Schottky barrier height and optoelectronic performance of the diodes. The results showed that reducing the Au deposition temperature significantly minimized thermal damage to the MoS2 surface and resulted in a larger Schottky barrier height. When the gate voltage was 0 V and Vds = ±5 V, the rectification ratios of the diodes deposited at 298 K, 173 K, and 77 K were 1.7 x 10², 5.8 x 10², and 9.6 x 10³, respectively. Under a gate voltage of 20 V at 77 K, the rectification ratio reached 10⁴, demonstrating that low-temperature deposition effectively suppresses reverse current. Photocurrent measurements indicated that, under illumination, the current change in all three devices exceeded 10³ %, with a more pronounced photoresponse observed as the deposition temperature decreased. This indicates that low-temperature deposition not only improves the electrical performance of the devices but also enhances their optoelectronic response.
The findings of this research demonstrate that low-temperature EBE offers significant advantages in reducing surface damage, increasing Schottky barrier heights, and suppressing reverse current, presenting new potential avenues for the development of 2D material Schottky diodes. |
