照射閃爍光之蕭基二極體的導納模擬

Abstract

本論文提出模型來模擬照射閃爍光的蕭基二極體，分成四個部分，第一部分探討未照光之下缺陷隨外加小訊號提供的電容及電導值，模擬出未照光下的電性表現。第二部分提出如何以數學式子模擬閃爍光的開關行為，並探討閃爍光提供額外的電容及電導值，模擬出照射閃爍光之電容及電導變化量。第三部分研究儀器量測時給予樣品電壓小訊號，此小訊號與光的耦合現象，造成樣品暫態電容及電導值產生震盪，將數學式代入軟體模擬，並與實驗相互對照。第四部份觀察電容頻譜，對於電容頻譜中的每一個峰值討論，最後提出合理的猜測與解釋。本論文成功以數學式子模擬出照射閃爍光下的量子點樣品之光電耦合效應。

In this study, we demonstrate an analytical expression for admittance of InAs/InGaAs quantum dot embedded in a GaAs Schottky diode under flashing illumination. This thesis is divided in four parts. First, we discuss the capacitance and admittance of our model, which is a Schottky diode with a defect state embedded in. While we apply a small voltage signal, we can obtain excess capacitance and admittance supplying by the defect state. Second, we suggest an analytical expression for flashing illumination. We can obtain excess capacitance and admittance causing by flashing illumination. Third, while impedance analyzer is measuring samples, it exports a small signal voltage, which is going to coupling with optical signal from flashing light. We are going to simulate this phenomenon with Mathcad. Additionally, we try to explain the similarity and differences between simulated results and experimental results. At last, view of point goes to spectrum of capacitance. We explain each peak appearing in capacitance spectrum. In conclusion, we successfully simulate the electro-optic coupling effect in quantum dot sample under flashing illumination.