課題番号 ：S-18-NI-0028
利用形態 ：共同研究
利用課題名（日本語） ：機能性カーボンナノファイバー探針の作製と評価
Program Title (English) ：Fabrication and characterization of functional carbon nanofiber probes
利用者名（日本語） ：Gemma Rius1),種村 眞幸2)
Username (English) ：Gemma Rius1), Masaki Tanemura2)
所属名（日本語） ：1) バルセロナ マイクロエレクトロニクス研究所（スペイン高等科学研究院）,
2) 名古屋工業大学
Affiliation (English) ：1) Institut de Microelectrònica de Barcelona IMB-CNM-CSIC,
2) Nagoya Institute of Technology

１．概要（Summary ）
For the high resolution nanolithography technique, local anodic oxidation of the probe of atomic force microscope (LAO-AFM) is quite important. In order to achieve the higher patterning resolution, AFM probes should possess the following properties: i) higher aspect ratio, ii) good electrical conductivity properties and iii) hydrophobic character. Carbon nanofiber (CNF) AFM probes consisting of an amorphous carbon fiber, ~500 nm long and ~10-70 nm thick, which is grown onto the apex of the Si tip, is ideal in shape. Next step is the functionalization (higher electrical conductivity) of the CNF probes. In the NITech Nano-tech platform project, we tackled this subject, because the fabrication of CNF probes is the original technique of NITech [1].

２．実験（Experimental）
The functionalized (conductive) CNF probes were fabricated using the CNF growth system in the line-up of the equipment of NITech nanotech platform. The CNFs were grown on the commercially available Si cantilevers (Olympus AC240) using the Ar+ ion irradiation method. In order to increase the conductivity of the CNF probes, metal included CNFs and CNFs covered with metal thin film were prepared by supplying metals during the CNF growth and by coating the metal thin film after the fabrication of the pristine CNFs, respectively. The simultaneous measurements of the conductivity and force acting on the CNF were performed using the SEM system in the equipment line-up of NITech nanotech platform.
３．結果と考察（Results and Discussion）
Figure 1(a) shows a set-up (SEM image) of the simultaneous measurements of the electrical and mechanical properties of a metal included CNF in SEM. The CNF used here was about 65 and 500 nm in diameter and length, respectively. Figure 1(b) shows a current-voltage (I-V) characteristic of the CNF measured while acting the force of 2.7 N on the CNF. The ohmic property was clearly seen. The better I-V characteristics were obtained with increasing the force acting on the CNF.

Fig. 1 (a) Set-up (SEM image) of the simultaneous measurements of the electrical and mechanical properties of a metal included CNF in SEM. (b) I-V characteristics at the acting force of 2.7 N on the CNF.

４．その他・特記事項（Others）
[1] S. Sharma, G. Kalita, 種村 眞幸、”炭素系ナノ材料の低温合成・その場観察・実用化” 金属 88 (2018) 95-102.

５．論文・学会発表（Publication/Presentation）
なし

６．関連特許（Patent）
なし