Synthesis of Well Aligned Silicon Nanowire Arrays by Reflow of Photoresist Techniques

以光阻回流技術備製排列整齊之矽奈米線陣列

王譔博(C. P. Wang) ； 劉建惟(C. W. Liu) ； 高騏(C. Gau)

《機械技師學刊》 7卷2期 (2014/10) Pp. 1-7

https://doi.org/10.6208/JPME-2014-10-01

摘要

由氣－液－固態（VLS）生長過程的方法製備排列整齊的矽奈米線（SiNWs），在以下做介紹。目前使用氮氣做為載氣，而非氫氣。矽奈米線的生長條件是由氮氣與矽烷氣體的比例來控制。在T=620℃，P=333m torr發現漸縮的矽奈米線，藉由增加氮氣，漸縮參數會降低。漸縮的矽奈米線歸因於金催化劑擴散到奈米線的側壁導致體積減縮。然而，發現到氮氣和氧氣有相似的效果，可以延緩金催化劑的擴散，導致金催化劑的體積減小不那麼顯著，且使得矽奈米線生長成為非錐形。採用光阻回流的技術，生長矽奈米線所需的金屬催化劑尺寸可以大大的降低，而且矽奈米線的生長位置可以在矽的表面訂出。另一種方法在奈米孔陣列中生長排列整齊的矽奈米線陣列也將展現出來。然而，通過光阻回流製成的奈米孔洞的高寬比對奈米顆粒金量之影響很大，因此對奈米線的品質和生長有顯著的影響。

關鍵字

陣列矽奈米線 ； 氣－液－固生長過程 ； 光阻回流

並列摘要

Well aligned Si nanowires (SiNWs) made by vapor-liquid-solid (VLS) growth process are presented. Instead of using H_2, the current work uses N_2 as carrier gas. The growth conditions of SiNWs are controlled by the ratio of nitrogen versus silane gas. Tapering of nanowires was found at T=620℃ and P=333 m torr, and the tapering parameter was reduced by increasing the N_2 gas. Tapering of nanowires is attributed to volume reduction of Au catalyst which diffuses onto the side wall of nanowires. However, it is found that the N_2 gas has a similar effect of O_2 gas which can retard diffusion of Au catalyst so that volume reduction of Au catalyst is not so significant and nanowire growth becomes untapered. By adopting reflow of photoresist techniques, the size of the metal catalyst for the SiNWs growth can be significantly reduced, and the growth location of the SiNWs can be defined on surface of Si. An alternative approach to grow the well aligned SiNW arrays in the nanohole arrays is also demonstrated. However, the aspect ratio of the nano size hole made by the reflow of the photoresist has a significant effect on the amount of the Au in the nanoparticles and thus the quality and growth of the nanowires.

並列關鍵字

arrays of SiNWs ； Vapor-liquid-solid growth process ； Reflow of photoresist