摘 要
此論文利用兩年時間研究二氧化釕、二氧化銥奈米桿化學氣相沉積在Zn/Si、LiNbO3(100)、SA(012)、SA(100)基材表面的選區成長。這些一維奈米桿垂直陣列於LiNbO3(100)、SA(100)表面，傾斜陣列於SA(012)表面，無方向性的成長於Zn/Si基材。這兩種奈米桿都是沿金紅石結構的[001]方向生長，二氧化釕奈米桿表面含有多出計量比的氧，這些過多的氧可以用氬離子束清除。二氧化釕奈米桿選區成長在Zn/Si與LiNbO3(100)基材表面實現，當沉積溫度設定500C時，有最清晰的成長區非成長區定義，選區成長之物理緣由可追溯至成長非成長表面的成核能障差異，氧化矽玻璃表面的成核能障使其成為理想的非成長表面。若沉積溫度低於500C，成長區非成長區定義較不清晰，因為成長物種在表面的遷移不夠快，若沉積溫度高於500C，成長區非成長區定義清晰，但奈米桿成長受到抑制，奈米桿的抑制，我們相信與高價氧化物的脫附有關。
二氧化銥奈米桿的選區成長也可以實現，其最佳沉積溫度450C，選區的原理相信與二氧化釕奈米桿相同，用微影蝕刻的製程進行選區圖案定義，優於前面用於二氧化釕奈米桿圖案化的銅網遮罩方法。二氧化銥SA(012)表面初期成長顯示晶核的有趣分佈行列，這種晶核的分佈相信與表面缺陷有密切的關係。

ABSTRACT

The area-selective growth of RuO2 and IrO2 nanorods on Zn/Si, LiNbO3(100), SA(012), and SA(100) substrates has been investigated in the last two years. These one-dimensional rods are vertically aligned on LiNbO3(100) and SA(100), tiltedly aligned on SA(012), and randomly oriented on Zn/Si substrate. The growth direction is [001] of rutile crystal for both nanorods. The surface of RuO2 nanorods contains excess oxygen higher than the stoichiometric ratio. The excess oxygen can be removed using argon sputtering. The selective growth of RuO2 nanorods is demonstrated on the Zn/Si and LiNbO3(100) surfaces. And the definition of growth and nongrowth region is most clear when the growth temperature is 500C. The physics of area-selective growth can be traced back to the nucleation barrier on growth and nongrowth surfaces. The higher nucleation barrier on silica surface makes it an ideal nongrowth surface. When the growth temperature is lower than 500C, the definition is less clear since the mobility of growth species is reduced. When the growth temperature is higher than 500C, the definition is clear but the growth of nanorods is inhibited. The inhibition of 1D structure is believed to be related to the desorption of higher oxides.
The area-selective growth of IrO2 nanorods is also realized. The optimum growth temperature is 450C. The principle behind the growth and the nongrowth control is believed to be the same with that of RuO2 nanorods. The exposure-and-etching technique is utilized in patterning the IrO2 selective growth regions, and found to be superior to the patterning technique of copper grid that is used in patterning the RuO2 selective growth. The initial growth study on IrO2 reveals interesting distribution configuration of nuclei on SA(012) surface. The distribution of nuclei is believed to be intimately related to the surface defects.

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