此論文研製了P通道二硒化鎢MOS場效應電晶體，使用了石墨烯做(Graphene)為電晶體的源極與汲極；二硒化鎢(WSe2)做為電晶體的通道。電晶體中的二維材料皆以化學氣相沉積的方式製程，因此可有更高品質、面積更大的二維材料薄膜，並對二維材料進行拉曼與光激發螢光之光學分析確認薄膜品質。對於二硒化鎢(WSe2)與大多數金屬接觸都呈現較大接觸電阻(Schottky Contact)，所以如何降低接觸電阻是製程P通道二硒化鎢MOS電晶體的重點之一，製程中將以石墨烯(Graphene)做為源極與汲極降低接觸電阻以達成歐姆接觸(Ohimc Contact)。在閘極堆疊製程時，將先以電子槍蒸鍍的製程方式在二硒化鎢表面蒸鍍附著層，以便接下來的原子層沉積二氧化鉿之製程。製程完成後之元件電性量測，可以得到單極性ID-VG 之電性曲線，電流開關比約105；次臨界擺幅約200 mV/dec.

This thesis reports the fabrication of P Channel WSe2 MOS field effect transistors. Here, graphene is used as the source and the drain, tungsten diselenide (WSe2) as channel material. All 2D materials were fabricated by Chemical Vapor Deposition such that high quality and large area film can be achieved. Raman spectrum and photo luminance were performed on the 2D films to ensure their qualities. Since the contact resistances of the WSe2 film with most metal are very high due to the nature of Schottky Contact, thus reduction of contact resistance is a major challenge for WSe2 MOS field effect transistors. In this thesis, the use of graphene as source/drain is proposed to lower the contact resistance and to achieve Ohmic Contact for unipolar conduction. As for the gate stack, an E-gun evaporated adhesion layer is adopted before the deposition of HfO2 by Atomic Layer Deposition. A unipolar ID-VG characteristics for the fabricated WSe2 MOS field effect transistors is observed with an ON/OFF ratio as high as 105 and a reasonable subthreshold swing of 200 mV/dec.

摘要 i
Abstract ii
內文目錄 iii
附圖目錄 v
第一章 序論 1
1.1 摩爾定律(Moore's Law) 2
1.1.1 摩爾定律的瓶頸 3
1.1.2 影響與應對 3
1.2 研究動機 5
第二章 二維材料與元件 6
2.1 石墨烯(Graphene)介紹與製程 6
2.2 二硒化鎢(WSe2)介紹 10
2.3 二硒化鎢電晶體 12
第三章 製程流程 13
3.1 化學氣相沉積(CVD)之石墨烯製程與轉移 14
3.1.1 石墨烯拉曼光譜分析(Raman Spectra Analysis) 16
3.1.2 石墨石墨烯圖案化及定義通道長度 20
3.2 化學氣相沉積(CVD)之二硒化鎢(WSe2) 23
3.2.1 二硒化鎢拉曼光譜分析(Raman Spectra Analysis) 26
3.2.2 二硒化鎢光激發螢光分析(Photo-Luminescence Analysis) 28
3.2.3 二硒化鎢圖案化定義通道寬度與元件隔離化 31
3.3 源極/汲極金屬製程 31
3.4 閘極絕緣層製程 34
3.4.1 二硒化鎢薄膜之表面特性 34
3.4.2 電子槍蒸鍍(E-Gun Evaporation)與原子層化學氣相沉積(ALD) 35
3.5 閘極金屬製程 38
3.6 探針接觸孔製程 39
第四章 電性與分析 42
4.1 石墨烯降低接觸電阻之電性比較 42
4.2 絕緣層之附著層製程與電性比較 44
4.3 IDVG、IDVD與厚度之電性比較 46
4.4 電性分析與快速熱退火(RTA) 49
第五章 總結 52
5.1 結論 52
5.2 未來改善與計畫 53
參考文獻 54

參考文獻

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