電機資訊學院: 光電工程學研究所指導教授: 吳肇欣李奕德Lee, I-TeI-TeLee2017-03-022018-07-052017-03-022018-07-052015http://ntur.lib.ntu.edu.tw//handle/246246/272947本篇論文的主要研究為針對溫度效應對發光電晶體的光電特性之影響，藉由量測InGaP/GaAs發光電晶體，發現發光電晶體的電流增益會隨溫度而增加然而發光強度則隨著溫度而減少，並且發現發光電晶體隨著溫度的上升，光調變頻寬會隨著增強的新物理現象，此現象與傳統發光二極體的光調變頻寬會隨著溫度上升而下降之現象相反，主要由於在發光電晶體中基極集極介面之逆偏壓會將載子掃到集極區，使得載子濃度在基極集極介面趨近於零，少數載子在基極形成三角形的分布，生命週期較長的載子因而擴散至基極集極介面並被掃到集極區，所以溫度上升時，等效的複合週期幾乎維持定值使得光調變速度不隨之下降。 在溫度上升時，載子獲得較高的動能而有更高的機會跳出發光電晶體中的量子井而流到集極區，所以電流增益會隨溫度增加而增加，載子在基極中的傳輸時間(base transit time)也因此隨溫度上升而減少，進而使得載子從射極到集極的傳輸時間(emitter-to-collector transit time)隨溫度上升而減少且發光電晶體的截止頻率(f_T)隨溫度上升而上升，此現象也與異質介面電晶體(HBT)的現象不同其截止頻率隨溫度上升而下降。 載子逃脫出量子井的生命週期為溫度的指數函數，發光電晶體有潛力利用電流增益隨溫度上升而上升的現象而成為高解析度溫度感測器，一個高解析度溫度感測器的前端設計須具備越大的溫度產生之訊號及越小的雜訊，為了增加溫度產生之訊號，我們設計將兩顆發光電晶體串接形成達靈頓對，當溫度上升時，第一顆發光電晶體增加的電流將再被第二顆發光電晶體放大，所以此設計會使因溫度上升而增加的電流更顯著的增加，成為高解析度溫度感測器的前端設計。This thesis presents the effects of temperature on the light-emitting transistor (LET), specifically its effects on the DC I-V characteristics and the RF characteristics. The electrical and optical characteristics of the InGaP/GaAs LET with two undoped InGaAs quantum-wells (QWs) embedded in the base region operated from 25℃ to 55℃ are demonstrated. The LET is a unique semiconductor optoelectronic device with both electrical and optical outputs, which provides potential applications in future optical interconnects and photonic integrated circuits. LETs and transistors lasers (TLs) have gotten a lot of attention due to their high-speed characteristics and potential for use in the next era of Internet of Things (IoT). At elevated temperatures, the current gain of the LET is increased and the optical modulation bandwidth is also enhanced. Both findings are interesting and contradictory to the behaviors of conventional heterojunction bipolar transistors (HBTs) or light-emitting diodes (LEDs). The physics of temperature-induced carrier dynamics in the active region of LETs is unique and resulted from the inherent transistor tilted-charge population instead of stored-charge population of diodes. The effective base transit time will decrease with temperature due to the reduction of thermionic emission lifetime. As a result, the cut-off frequency of the LET increases with the temperature which is also different from the conventional HBTs. The thermionic emission in the quantum well increases with temperature resulting in the increase of the current gain. In order to increase the temperature-to-voltage signal for high resolution temperature sensor, the simple circuits are designed and fabricated. Due to the characteristic that the thermionic emission is sensitive to the temperature, it has the potential as the front end of the high resolution smart temperature sensor.2770970 bytesapplication/pdf論文公開時間: 2020/8/20論文使用權限: 同意有償授權(權利金給回饋學校)發光電晶體電流增益光調變速度截止頻率溫度感測器light-emitting transistorscurrent gainoptical bandwidthcut-off frequencytemperature sensorthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/272947/1/ntu-104-R02941055-1.pdf