Field-assisted oxygenetching for Niobium nanotip

• Main Authors: Huang, Quan-You, 黃詮友
• Other Authors: Fu, Tsu-Yi
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/02967126299440772123

碩士 === 國立臺灣師範大學 === 物理學系 === 104 === We present a straightforward modification technique for poly-crystal niobium tips in UHV. The modification technique is based on spatially controlling the reaction of oxygen gas with the surface atoms of a niobium tip in a field ion microscope (FIM). Confining this field-assisted etching reaction to the shank has enabled us to produce niobium nano- tips. Nano-tip formation is evident from the decrease in the FIM imaging voltage and the decrease in the apex area. We field-assisted etch niobium tip at three different temperature (25K，50K，80K). Then we compare the etching efficiency and FIM image quality. We measure the field emission electron current form the etched nano-tip and illustrate the F-N plot. The F-N plot shows that the shape of the etched tip will change after thermal treatment. We also measure the stability of the field emission current from the etched niobium nano-tip in 30 minute. When the emission electron current is 434pA, the instability is less than 10%.