- 學位論文
射頻磁控濺鍍法製備大面積的單層石墨薄膜
Large area graphene prepared by high temperature FR-sputtering
摘要
大面積的單層石墨薄膜在製作電子元件上是有其必要性的。到目前為止，雖然CVD成長以及SiC昇華這兩種方式廣泛運用在製作大面積的石墨薄膜上，但是其表面的均勻性還是需要改善。在這篇論文裡，我們試著使用射頻磁控濺鍍法將我們的石墨薄膜高溫成長於Si(111)的基板。藉由拉曼光譜以及x光光電子能譜，我們發現隨著成長溫度的提升，產生了更多的sp2鍵結以及D-peak高度的提升。而這些現象指出了非晶石墨薄膜的形成。另外，藉降低成長功率，D-peak/G-peak的比例也有明顯的增高。而這可以歸因於在不同的濺鍍功率下會產生不同大小的碳塊沉積在基板上，而較小塊的碳塊會更容易形成鍵結，進而形成石墨薄膜。此外，我們也使用膠帶剝離法來製備石墨薄膜及製作元件，拉曼及電性的量測結果會分析於論文內。
關鍵字
單層石墨薄膜並列摘要
Large-area uniform graphene is required for the development of graphene electronics. Until now, although large-area graphene films can be prepared by either chemical-vapor deposition or SiC substrate sublimation, the uniformity of the films is still unacceptable for practical applications. In this thesis, graphene films are grown on Si (111) substrates by using a RF-sputtering system at high temperatures. Through XPS and Raman measurements, increasing sp2 bonding compositions and D-peak intensities with increasing growth temperatures are observed, which suggest a amorphous carbon film with graphene grains is obtained via this approach. Also observed is the increase of D-peak/G-peak ratios with decreasing RF powers. The results suggest that the growth of graphene films with even better uniformity by using the RF sputtering technique is limited by the C flake sizes deposited on the substrates at the first place. The phenomenon indicates that by supplying even smaller C flakes, graphene films with better crystalline qualities could be obtained. For comparison, the Raman spectrums and I-V characteristics of graphene flakes and devices fabricated by using exfoliation of Scotch tapes from the HOPG are also shown in this thesis.