在現今半導體矽製程不斷進行尺寸微縮的發展下，會遭遇到短通道效應等諸多問題。二維材料被認為是有機會取代矽成為新一代半導體材料的候選人。不同於二維材料中的研究熱門過渡金屬二硫族化合物(Transition metal dichalcogenide, TMDCs)，硒化銦(InSe)屬於三六族層狀半導體的一員，InSe擁有較小的有效電子質量以及廣而可調變的直接能隙範圍，因此被視為是非常有潛力的一個半導體材料。

類似於黑磷的化學不穩定性造成InSe非常容易受到大氣中的水氧氧化 影響元件表現。本論文中利用90 torr的純氧環境對InSe做表面保護處理，發現經過6小時的氧化處理的元件，其特性比起經過大氣水氧氧化的元件有了大幅度的提升(遷移率從18.52 cm^2/V.s 提升到362 cm^2/V.s)。接著再利用電流遲滯大小與電流-時間關係量測來確認InSe氧化層的品質。另外經過比較發現電子束微影製程會對材料造成損傷，因此使用銅網當作金屬遮罩來製作元件能夠避免高能電子束的影響。

最後我們將PbS量子點旋塗在InSe元件表面，希望能看到光致電荷轉移的現象，然而由於逐層沉積配位基交換過程使用的化學藥品會損害到材料，因此沒有看到如預期的電流增大效果。

In the presence of short channel effect along with device scaling down, the use of 2D materials may be a possible solution. Indium selenide(InSe), which belongs to III-VI group layered semiconductors, is a promising material with small electron effective mass and large tunable bandgap.

Instability like black phosphorus making InSe devices easy to be affected by water and O_2 molecules. In this thesis, surface treatment by 90 torr, pure oxygen environment was made to form a protective oxide layer. By comparing transport characteristics of devices with different oxidation time, we find that 6-hours-oxidation device had the best performance. Next, we measured current hysterysis and I-T curves of devices to confirm different oxide quality. Furthermore, we find that using e-beam lithography to scale down channel length may largely degrade device performance.

Finally, in order to improve device performance by photo-assisted charge transfer, we deposited PbS quantum dot on InSe devices. The result showed that chemicals used in ligand exchange process will damage InSe channel, therefore the improvement of transport characteristics can not be seen.

論文摘要.................................. I
Abstract.................................... II
目錄.......................................... III
第一章序論............................... 1
1.1 半導體技術演進 . . . . . . . 1
1.2 矽製程的微縮與侷限 . . . . 2
1.3 金屬半導體接觸特性. . . . . 6
1.4 論文結構 . . . . . . . . . . . . . 8
第二章二維材料介紹................. 9
2.1 二維材料的發展. . . . . . . . . 9
2.2 硒化銦介紹. . . . . . . . . . . . . 12
第三章硒化銦材料檢測與特性.... 17
3.1 硒化銦拉曼光譜檢測. . . . . . . 17
3.2 硒化銦光致螢光光譜檢測. . . . 20
3.3 硒化銦原子力顯微鏡檢測. . . . . 23
3.4 X射線光電子能譜檢測. . . . . . . . 24
第四章硒化銦場效電晶體製作流程... 27
4.1 硒化銦表面氧化. . . . . . . . . . . . . 28
4.1.1 不同氧化條件的材料檢測. . . . . 28
4.2 元件製作流程. . . . . . . . . . . . . . . . 32
4.2.1 金屬遮罩 . . . . . . . . . . . . . . . . . 32
4.2.2 熱蒸鍍系統 . . . . . . . . . . . . . . . 34
4.2.3 電子束微影. . . . . . . . . . . . . . . . 35
第五章硒化銦場效電晶體量測結果與分析....... 37
5.1 氧化時間對元件載子遷移率的影響. . . . . . 37
5.2 低壓氧化元件的電流對時間量測比較 . . . . 44
5.3 電子束微影對元件載子遷移率的影響. . . . . . 50
第六章硫化鉛量子點對硒化銦場效電晶體的影響...... 53
6.1 硫化鉛量子點的載子轉移機制 . . . . . . 53
6.2 硫化鉛量子點覆蓋元件製作流程. . . . . 54
6.3 硫化鉛量子點覆蓋元件量測結果與討論. . . . . 55
第七章結論與未來展望................... 61
參考文獻....................... 63

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