管傑雄臺灣大學：電子工程學研究所王盈翔Wang, Ying-HsiangYing-HsiangWang2007-11-272018-07-102007-11-272018-07-102007http://ntur.lib.ntu.edu.tw//handle/246246/57213紅外線偵測器在民生，軍事，及科學上已被廣泛使用。其中的應用，如目標物辨識或是溫度感測，需要多彩的紅外線偵測器。在這篇論文中，我們設計超晶格包含在兩厚位障的週期結構，此紅外線偵測器的偵測範圍橫跨7~16 μm，並展現電壓調變光響應的特性。 元件受摻雜遷移遷移的影響而存在內建電場，使得元件有開路響應，存在光致電壓模式。在極低偏壓下，內建電場主導能帶。開路響應存在兩個波峰，這兩個波峰所對應的能態運動方向相反，因此在低偏壓同樣強度不同極性下有相異的響應。我們提出受內建電場影響的能帶圖，並經由理論計算得到對應的兩個能態，及其運動相反的原因。 在高偏壓下，外加電場主導能帶，除了能障外，超晶格區域亦有跨壓。能帶彎折影響躍遷能量的改變。光響應隨偏壓加大可以觀察到五個波峰，異於以平能帶計算的四個波峰，我們提出高偏壓下的能帶圖，重新計算，歸納出每個躍遷能量所對應的能階。 響應亦受溫度影響，元件在低偏壓下，電子受費米-德瑞克分佈函數分佈，整體響應皆隨溫度上升而變大。隨著偏壓增加，電子受到穿遂效應與散射效應的影響，響應出現分界點，分界點並會隨偏壓上升而跳至鄰近長波長的波峰，呈現兩個分界點的現象。 　　藉由此結構，我們的偵測器擁有寬頻的光響應。The infrared photodetectors are important in many civilian, military and scientific applications. Some of them, for example temperature sensing and target discrimination, require the infrared photodetectors to be equipped with the ability of multicolor detection. In the thesis, a new structure of superlattices bounded by two thick barrier was investigated. The detection range of this infrared photodetector was 7~16μm, and the detector showed the voltage-tunable characteristic. Due to dopant migration, build-in electric field exists in the device. There is open-circuit photoresponse, the detector can operate in photovoltaic mode. Under ultra low bias, build-in electric field dominates the energy band. There are two peaks in the open-circuit photoresponse. Photoelectrons in the two energy states which corresponding to the two peaks move to different direction. Therefore, response is different under same amplitude but different bias polarity. We presented the energy band diagram affected by build-in electric field. 　　Under high bias, applied electric field dominates energy band. Voltage drops not only on the barrier but also in the superlattice region. Transition energy changes because of band-bending. We observed five peaks in the response as applied bias increased. These five peaks are different from four peaks calculated by flat-band. We presented the energy band diagram under high bias. Recalculated the energy level, we concluded the ground states of each transition energy. Response is also affected by temperature. Under low bias, electrons follow Fermi-Dirac distribution. Whole response increases as temperature increases. While bias increase, electrons is affect by tunneling and scattering effect. There is a crossing point in the response. The crossing point jumps to next long wavelength peak as bias increases, and the crossing points become two. With this structure, our detector has broad-band response.口試委員會審定書...………………………. ...i 英文簽名頁..……..…………………………. ii 誌謝……….……..…………………………. iii 中文摘要…..……..………………………… iv 英文摘要…..……..………………………… v 第１章 1 導論 1 1.1紅外線頻段 1 1.2 黑體輻射與熱輻射 1 1.3 紅外線偵測器種類 2 1.4 內能帶躍遷光偵測器 3 1.4.1 光致電導量子井紅外線偵測器 4 1.4.2 光致電壓超晶格紅外線偵測器 5 1.5 轉移矩陣技術 7 1.5.1 理論介紹 7 1.5.2 程式計算 9 1.6 章節架構 10 第２章 11 製程與元件的量測 11 2.1 製程步驟 11 2.1.1 樣品清潔 11 2.1.2 微影 12 2.1.3 濕蝕刻 13 2.1.4 金屬蒸鍍及金屬剝離 13 2.1.5 退火 13 2.1.6 斜角研磨與鎊線 14 2.2 儀器架設與特性量測 15 2.2.1 傅利葉轉換紅外線光譜儀(FTIR)的介紹 15 2.2.2 相對光譜響應 16 2.2.3 絕對響應 17 2.2.4 電流-電壓特性 18 2.2.5 偵測率 19 第３章 21 理論計算與實驗結果 21 3.1 偵測器結構 21 3.2 理論計算 23 3.3 溫度20K下的響應 25 3.3.1 極低偏壓的響應 25 3.3.2 低偏壓與高偏壓的響應 28 3.4 溫度相依的響應 30 3.5 電流-電壓特性 33 3.6 偵測率 34 第4章 38 討論 38 4.1 內建電場與外加電場對能帶的影響 38 4.1.1 極低偏壓下內建電場主導能帶 38 4.1.2 高偏壓下外加電場主導能帶 42 4.2 溫度相依的響應 47 4.3 溫度相依的偵測率 48 第5章 49 結論 49 參考文獻 512383270 bytesapplication/pdfen-US紅外線偵測器超晶格量子井寬頻光響應開路響應Infrared photodetectorssupperlatticeQuantum wellsBroadband responseopen-circuit response[SDGs]SDG7thesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/57213/1/ntu-96-R94943056-1.pdf