二維材料（2D-materials）被認為有機會能取代矽（Si），成為新的半導體材料。除了常見的石墨烯（Graphene）和過渡金屬二硫族化物（Transition metal dichalcogenides, TMDCs）以外，三六族化合物半導體最近也被拿來廣泛研究，其中硒化銦（InSe）為一種n型的半導體材料，塊材時具有1.26 eV的直接能隙，隨著厚度的降低能隙會逐漸上升，到了最後會轉變為間接能隙。論文中使用機械剝離法撕出厚度為14到15 nm左右的硒化銦晶體，藉由光致螢光（Photoluminescence, PL）光譜的檢測顯示能隙為1.33 eV，此能隙大小對應到紅外光的波段，因此整個可見光到紫外光的波段都能被偵測到。本論文中探討了表面氧化對硒化銦的影響，利用反應離子蝕刻機產生氧電漿對材料表面進行氧化，不同的氧化時間會得到不同的元件遷移率及光響應，其中以氧化25秒的元件具有較大的遷移率為235 cm^2/Vs，而在閘極偏壓為80 V、白光入射光強度為0.08 mW/cm^2時量測到的光響應為8.362*10^3 A/W，同一個元件改為使用綠光照射並計算外部量子效率，其數值達到19141%。此外對氧化25秒的元件進行探測率的計算得到1.4*10^13 Jones，最後針對氧化25秒的元件在關狀態下量測光電流對時間的變化，亮電流降到暗電流的時間為150微秒，暗電流升到亮電流的時間為50微秒，為相當快的響應速度。另外本論文結合量子點與硒化銦，試圖藉由量子點來更進一步強化硒化銦的光電特性，但由於硒化銦本身不穩定的化學性質，因此沒有看到預期的效果。

Group III-VI compound semiconductors are one of important 2D-materials. The most intensively studied group III–VI material with MX stoichiometry is InSe. Bulk InSe is a typical n-type semiconductor with a direct band gap of 1.26 eV. The direct band gap of InSe used in this thesis is about 1.33 eV corresponding to the PL spectra. This value correspond to the thickness of about 14-15 nm. The InSe photodetectors are broad spectra responsive from UV-visible to near infrared. In this thesis, we discuss the effect of surface oxidation on InSe. Different oxidation time creates distinct trap concentration in InSe. For the InSe FET oxidized for 25 seconds, the electron mobility is up to 235 cm^2/Vs at room temperature. It also have high response to visible light, exhibiting a photoresponsivity of 8.362*10^3 A/W under white light illumination with irradiance of 0.08 mW/cm^2. The EQE of the same device reaches 19141% under green light illumination with the wavelength of 530 nm and irradiance of 0.08 mW/cm^2. The device exists ultrafast response. The rise time and fall time is about 50 us and 150 us respectively. We deposit PbS quantum dots on the surface of InSe by spin-coating to enhance the performance of the devices. The unsatisfying result may attribute to the reaction between InSe and solutions used in ligands exchange process. PbS cannot work without ligands exchang because the original ligands attached on the surface of PbS quantum dots are too long for electrons to transfer into InSe.

Abstract......................................................I
摘要........................................................III
目錄.........................................................VI
第一章 序論...................................................1
1.1 半導體的歷史與演進.........................................1
1.2 矽基半導體微縮的侷限.......................................3
1.3 半導體光電元件.............................................6
1.3.1 光偵測器................................................7
1.3.2 光導體..................................................9
1.4論文結構...................................................12
第二章 二維材料介紹............................................13
2.1 二維材料的發展............................................13
2.2 三六族化合物介紹...........................................15
第三章 硒化銦材料分析..........................................21
3.1 拉曼光譜檢測..............................................21
3.2 光致螢光光譜檢測...........................................25
3.3 原子力顯微鏡檢測...........................................27
3.4 X射線光電子能譜檢測........................................29
第四章 硒化銦場效電晶體製程介紹.................................31
4.1 硒化銦表面氧化.............................................31
4.2 元件製作流程..............................................36
4.2.1 金屬遮罩................................................36
4.2.2 熱蒸鍍系統..............................................38
第五章 硒化銦場效電晶體的光電量測結果與分析......................41
第六章 硫化鉛量子點對硒化銦場效電晶體的影響......................61
6.1 硫化鉛量子點的作用機制介紹..................................61
6.2 硫化鉛量子點元件的製程.....................................64
6.3 硫化鉛量子點元件的光電量測結果與討論........................64
第七章 結論與未來展望..........................................69
參考文獻......................................................71

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