以自發電化學反應簡易製備大範圍矽奈米線陣列

Abstract

矽奈米線以其半導體性質與發展為各式元件的極大潛力，受到學術界注意。本論文報導一種簡單的方法，解決以固－液－氣法合成矽奈米線的諸多缺點。可在常溫、常壓、大氣、水相條件下，不需外加任何形式能量，即可利用自發的電化學反應，以硝酸銀╱氫氟酸水溶液在矽晶片表面大範圍地生成單結晶的矽奈米線陣列。為了進一步縮小與均化線徑，同時讓陣列排列得更緻密整齊，矽晶片的表面被用濺鍍和燒結的方式做出一層金奈米粒子。以此做為反應發生的起始點，可得到線徑更細小、更一致、更緻密的產物。調整金奈米粒子的粒徑，可間接控制砂奈米線的線徑。將反應液中的硝酸銀更換為硝酸銅或六氯鉑酸鉀，可利用同樣的原理，在矽奈米線陣列表面修飾上一層銅或鉑的奈米粒子，更增加其實際應用的可能性。

Owing to the semi-conductor properties and the great potential for developing various applied devices, there has been growing concern in academics about silicon nanowires (SiNWs) recently. In this thesis, a simple method via electroless metal deposition (EMD) has been reported. This method can circumvent the shortcomings of SiNWs synthesis based on the vapor-liquid-solid (VLS) mechanism. By employing the spontaneous electrochmical reactions with silver nitrate / hydrofluoric acid solution, large areas of single crystal SiNW arrays were produced on silicon wafer in aqueous solution under room temperature, standard pressure, and atmosphere conditions. In order to decrease the SiNWs’ diameter and improve the uniformity, silicon wafers coated with gold nanoparticles (AuNPs), which were prepared by sputtering and annealing, were used as the starting material. When the electrochemical reaction started on AuNPs, the products with smaller, tidier, and more consensus wire diameters were obtained. Replacing silver nitrate with cooper nitrate or potassium hexachloroplatinate in the reaction solution, copper or platinum nanoparticles were coated on SiNW arrays, which further increase the applicability of the products.