以分子束磊晶技術成長的二維電子氣氮化銦鎵與氮化鋁異質接面之成長與特性研究

Study of growth and characteristics of two dimensional electron gas (2DEG) InGaN/AlN heterostructure grown by molecular beam epitaxy

沈宥竹(Yu-Chu Shen)

指導教授 ： 周武清

國立交通大學/理學院/電子物理系所/碩士(2020年)

摘要

本論文研究以分子束磊晶系統成長氮化銦鎵薄膜與氮化鋁/氮化銦鎵異質結構於以有機金屬氣相沉積法所製備的氮化鎵基板上，目的是優化半導體特性以應用於高頻與高功率之高電子遷移率電晶體。特性利用低溫光激螢光光譜、低溫反射光譜與X光繞射分析。並且使用原子力顯微鏡、掃描式電子顯微鏡及於磊晶過程即時觀察反射式高能電子繞射圖形，分析其表面形貌。再透過調變銦、鎵元素通量與長晶溫度，成長銦組成含量為3.9% 至14.4%的氮化銦鎵薄膜樣品，而表面粗糙度低至0.63 nm，且並無相分離的現象。而後使用較高銦組成含量(14.4%)的氮化銦鎵作為通道層，成長氮化鋁/氮化銦鎵異質結構，其二維電子氣載子遷移率為515 cm2/V，而最佳的片電荷濃度為1.54×1013 cm-2，片電阻值為789 Ω/sq。

關鍵字

分子束磊晶 ； 氮化銦鎵 ； 二維電子氣 ； 螢光光譜 ； 反射光譜 ； 表面特性

並列摘要

Molecular beam epitaxy was used to fabricate the InxGa1-xN thin films and AlN/InGaN hetero-structures on the GaN substrates grown by metal organic chemical vapor deposition to optimize the characteristics for the application in the high electron mobility transistor (HEMT) of high frequency and high power. The optical properties were studied by photoluminescence (PL), reflectance spectroscopy (R) and X-ray diffraction (XRD). The morphology was analyzed by atomic force microscopy (AFM) and scanning electron microscopy (SEM), and in-situ reflective high energy electron diffraction. By the control of In/Ga flux ratio and growth temperature, we successfully optimized the InxGa1-xN (x=0.039 ~ 0.144) epilayers without phase separation and achieved the surface roughness of 0.63 nm. The electron mobility μ=515 cm2/V, sheet carrier concentration n=1.54x1013 cm-2, and sheet resistance R=789 Ω/sq could be achieved in the AlN/InxGa1-xN two dimensional electron gas (2DEG) hetero-structures with a high composition InxGa1-xN (x=0.144) channel layer.

並列關鍵字

MBE ； InGaN ； 2DEG ； PL ； reflectance ； morphology

參考文獻

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