以蒙地卡羅方法分析氧化鋅鎂/氧化鋅薄膜層載子遷移率

Mobility Study of Polycrystalline MgZnO/ZnO Thin Film Layers with Monte Carlo Method

黃智怡(Chih-I Huang)

指導教授 ： 吳育任

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.00204

摘要

近年來，由於透明電極和薄膜電晶體在光照和顯示技術上的應
用，關於透明電極和薄膜電晶體的研究變得越來越重要，因此，如
何製造高電子遷移率的透明電極和薄膜電晶體成為業界關注的問
題。在本論文中，我們利用蒙地卡羅的方法分析多晶格的氧化鋅鎂
�氧化鋅薄膜層的電子遷移率，我們的研究考慮了晶格界面散射、
電離雜質散射、聲子散射和合金散射對於的影響，我們利用二維帕
松和漂移擴散方程來計算晶格界面強度、晶粒大小和屏蔽效應對電
子遷移率的影響。此外，我們也提出了氧化鋅鎂薄膜層的臨界厚
度，透過適當的設計，我們可以利用調變摻雜的技術和自發及壓電
極化，降低晶界強度，並提高氧化鋅薄膜層的電子遷移率。

關鍵字

氧化鋅鎂/氧化鋅 ； 異質結構 ； 蒙地卡羅 ； 壓電極化 ； 晶格界面 ； 遷移率

並列摘要

The study of transparent conducting oxide (TCO) and thin film transistor (TFT) has become an important area due to the applications of lighting and display technology. Therefore, finding a high mobility and conductivity TCO materials would be a key issue to the industry. In this paper, we have applied the Monte Carlo method to analyze the mobility of single and poly-crystalline MgZnO/ZnO thin film layer. The effects of grain boundary scattering, ionized impurity scattering, phonon scattering as well as alloy scattering have been included in our program. The grain boundary potential, the grain boundary size and carrier screening effect has been analyzed with our developed 2D Poisson and drift-diffusion solver. The critical depth of the MgZnO layer is also presented in our study. With a careful design of modulation doping and including the effect of spontaneous and piezoelectric polarization, the grain boundary potential can be suppressed and thus the mobility of the ZnO layer can be improved.

並列關鍵字

MgZnO ； ZnO ； heterostructure ； Monte Carlo Method ； piezoelectric polarization ； grain boundary ； mobility

參考文獻

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