異質接面量子點之光與磁特性分析

Optical and magnetic properties of quantum dot heterostructures

陳柏瑋(Po-Wei Chen)

指導教授 ： 温武藝 ； 涂維珍

中原大學/電機資訊學院/電子工程研究所/碩士(2020年)

https://doi.org/10.6840/cycu202000524

摘要

量子點是一種奈米級別的半導體，具有特殊的光電特性，如生物相容性好、發光的穩定性、螢光壽命長、高的吸收係數、高激發光等眾多項優異性能。
本研究藉由光學模擬程式(RSoft FullWAVE)，以時域有限差分法(Finite-Difference Time Domain，FDTD)對Si與石墨烯(Graphene)量子點在矽基板上面進行模擬，並對不同粒徑大小、間距以及表面粗糙度來進行比較，當量子點的粒徑變大其電場會增強，而當量子點的間距變寬時，則電場值將減弱。最後模擬矽量子點的吸收頻譜，發現曲線產生藍位移。論文設計的結構可以應用於太陽能電池中，如非晶矽薄膜太陽能電池能吸收300 nm至700 nm的光與吸收700 nm至1100 nm紅外光的微晶矽薄膜太陽能電池，也能將石墨烯量子點/矽量子點複合材料作為鋰離子電池負極材料。

關鍵字

量子點 ； 光與磁

並列摘要

Quantum dot is a nanocrystal semiconductors material with unique photoelectric characteristics, such as high biocompatibility, great stability of light emission, long fluorescent life, high absorption coefficient,and high excitation light.
In this study, optical and magnetic properties of graphene/Si heterostructures are simulated base on the finite-difference time domain (FDTD) method. Graphene quantum dots with different sizes and distances on Si substrates are constructed to analysis electrical field intensity distributions and absorption spectra. The electric field intensity increases when the particle size of the quantum dot becomes larger, and when the distance of the quantum dot becomes longer, the electric field decreases. In addition, it is found that the absorption spectra is blue shifted as the size of quantum dots becomes smaller.
In the future, the proposed quantum dot/Si heterostructures can be applied for various solar cells, for example, amorphous silicon solar cells absorb incident light in the wavelength ranging from 300 nm to 700 nm and microcrystalline silicon solar cells absorb incident light in the wavelength ranging from 700 nm to 1100 nm. In addition, this heterostructure can be used for lithium ion batteries as an anode material .

並列關鍵字

quantum dot ； magnetic properties

參考文獻

參考資料

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