我們利用電化學蝕刻方法蝕刻純鈮針，製作出針徑接近50nm以內的針尖後置入超高真空中，經過反覆加熱退火處理得到一熱穩態結構，此結構為四個{310}皺化擠壓{100}切面。
我們利用惰性氣體(Xe、Ne)給予腔體不同的鋪覆環境，再量測由純鈮{100}切面發射出來的電流與施加的偏壓去繪出FN圖，再由FN圖上斜直線斜率經計算後得到鈮{100}的表面功函數。
發現鋪覆此兩種氣體後，鈮{100}切面的表面功函數會下降，下降幅度會隨著鋪覆的環境而變化，兩種氣體有所謂的最佳鋪覆環境，而在最佳鋪覆環境下的鈮{100}表面功函數會有最大的下降幅度，經過三次實驗的統計結果顯示在最佳鋪覆環境下，鈮{100}面鋪覆Xe後的表面功函數下降幅度比鋪覆Ne明顯。
並且我們量測純鈮{100}切面在最佳鋪覆環境下場發射電流三十分鐘後的穩定性，我們調控場偏壓、平均電流並觀察穩定性上的變化，發現純鈮{100}面的發射電流穩定性沒有比鋪覆Xe在最佳鋪覆環境下的電流穩定。

We fabricate a thermally stable pure niobium tip with a small (100) facet faceting structure surrounded by four {310} surfaces by thermal treatment in UHV.
We observe the thermally stable structure by field ion microscopy (FIM) and measure field emission current from the niobium (100) facet with a Faraday cup. After exposing the tips under various gas (Ne, Xe) environments(1 Langmuir), we measure the emission currents at various applied voltages. Variation of field-emission work functions due to different absorption gases can be observed from the illustrated F-N plots. We find Xe gas noticeably reduces the work function of the niobium (100) facet.
We measure stability of the field emission current from niobium {100} facet with Faraday cup in 30 minunits.

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