氮化鎵奈米線之CVD製作研究

Study on the CVD Process of GaN Nanowire

蔡國銘(Kuo-Ming Tsai) ； 謝忠祐(Chung-Yu Hsieh) ； 姚潔宜(Chieh-Yi Yao) ； 廖堃宏(Kun-Hung Liao)

《勤益學報》 23卷1期 (2005/06) Pp. 1-15

https://doi.org/10.6753/CYJ.200506.0001

摘要

本研究主要是探討以化學氣相沈積法生長氮化鎵(GaN)奈米線及製程條件對氮化鎵奈米線與氧化矽(SiO(下標 x))奈米線陣列形態的影響。實驗參數使用Fe/Co/Ni/Al搭配不同組合之硝酸鹽晶體作為反應催化劑，反應溫度為915℃，反應氣體為氨氣，流量60sccm，反應時間為10分鐘至10小時。
由實驗結果可發現不同的催化劑對氮化鎵成長形態有不同的影響，且在基材上亦成長不同形態的氧化矽奈米線陣列。因氧元素對矽有良好的親和性，加上鎵金屬元素是氧化矽最佳之觸媒，在實驗結果中呈現氧化矽會伴隨著氮化鎵成長，而造成氧化矽奈米線的量大於氮化鎵奈米線的量。
由SEM觀察結果知，在奈米線的頂端未發現觸媒金屬顆粒，因而確認此為氣體－固體(Vapor-Solid, VS)成長機制。經實驗觀察氮化鎵所呈現的形態有線狀、片狀與三角柱狀，線狀最小直徑約為50-70nm、長約10-20μm。另外，氧化矽奈米線形態約有直線陣列、球狀、蜂巢狀、層狀、樹叢狀、蓮花頂樹叢狀與尖錐球狀等等。

關鍵字

CVD ； 奈米線 ； 氮化鎵 ； 氧化矽

並列摘要

Nanowires of GaN and SiOx were synthesized through chemical vapor deposition processes. This research is aimed at studying the effects of processing parameters on morphology of the nanowires. Different combinations of Fe/Co/Ni/Al nitrates were employed as catalysts. A temperature of 915℃, an ammonia gas flow rate of 60sccm and a reaction time of 10 minutes to 10 hours were used during the CVD process.
The morphology of GaN nanowires produced was determined by the types of catalysts used. A by-product of different types of SiOx nanowire arrays were formed on the silicon substrate. Since the difference in electro-negativity between oxygen and silicon is rather high, together with the fact that gallium be the best catalyst for forming silicon oxide, the amount of SiOx produced was found to be greater than that of GaN.
Bare GaN nanowires without catalyst particles at the tips were observed in SEM micrographs, suggesting a vapor-solid (VS) mechanism of growth. GaN with morphologies of wires, platelets as well as triangular nano-rods with lengths of 10-20μm and diameters of 50-70 nm, were produced. Silicon oxide with morphologies of nanowire arrays, spheres, honeycombs, lamina, dendrites, showerhead and spiky-balls were also observed.

並列關鍵字

Chemical Vapor Deposition VCD ； Nanowires ； Gallium ； Nitride ； Silicon Oxide