在此研究中，我們舖覆白金原子於鎢針表面，並加熱至約1000K，成功於W(111)位置成長金字塔形單原子針尖。我們發現兩種金字塔形單原子針尖結構，分別是針尖由上往下排列為一顆、三顆、十顆與一顆、六顆、十五顆兩種類型，也利用原子間的蒸發場差異發現其乃由基底原子在內部形成的金字塔形排列並在其外覆以白金原子所構成。我們也發現並解釋金字塔形針尖的上層原子排列與整體金字塔形排列有些許角度上的偏差，另外也研究單原子針尖無法在太鈍的針上形成的原因。在應用方面，我們提出了新型針尖蝕刻法與利用電鍍方式於鎢針上覆鈀，使其能適用於大量製造掃描穿隧顯微鏡的探針。另外，金字塔形結構的場發射研究發現F-N plot 分析中斜率的減少，很可能是電子共振穿隧所造成。

Depositing Pt atoms then annealing at 1000K can create single-atom sharp pyramidal W tips wrapped in a Pt overlayer. There are two types of single atom pyramidal tip structures. One we named type 1, which constituted with 1, 3, and 10 atoms from top to bottom layers. The other we named type 2, which constituted with 1, 6, and 15 atoms from top to bottom layers. The atom arrangements of pyramidal structure are determined to be inner W atoms covered with one-monolayer Pt atoms by the differences of the field evaporation resistive between Pt and W atoms. Additionally, we explained the angle deflection between the top three atoms and the whole pyramid. We also study why single atom can’t be grown on too blunt tip. In applications, a new etching and electrochemical deposition method was suggested. Therefore, the single atom tip, which is proper for STM probe, may be produced routinely. Moreover, the F-N plots of field emission of the pyramidal structure show the slope reduction. It may be due to the electron resonant tunneling effect.

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