微焊接技術探討與微電路製備

Abstract

有鑑於原子力顯微術（Atomic force microscopy，簡稱AFM）在奈米科技發展的應用潛力，本論文擬以導電模組原子力顯微技巧（Conducting-mode AFM）製備出微型電流調節閥裝置（Current rectifier）。根據本實驗室過去經驗，若對AFM探針施加偏壓，其針端電場可引起局部氧化（AFM-based field-induced local oxidation，簡稱ALO），使Phenothiazine化合物，如Thionine，進行氧化聚合反應而固定於探針下方導電載體表面。由於這些聚合高分子具有導電性，故可作為微焊接著物。此外，根據文獻報導，奈米碳管具有優越電子傳導能力。若能結合這兩種物質的特性，便可藉以製備微電流調節閥，探討電子在奈米碳管表面的傳導機制。實驗結果顯示多層奈米碳管是半導體，幾乎不具電子傳導功能，但若在其兩端以微焊技術焊上Thionine，則可使電流在其表面流通，顯示本論文所發展的微焊技術極具應用潛力。In the light of the potential of the Atomic force microscopy (AFM) in the development of nanotechnologies, we study the possibility of developing any microsoldering technique to fabricate the carbon nanotube-based current rectification devices with the conducting-mode AFM techniques. According to our previous experiments, the AFM tip can induce electrical field to cause local oxidation (ALO) of phenothiazine compounds, such as thionine, as being applied with bias voltages. Since the phenothiazine after ALO can form polymer with appreciable conductance, it shows potential as a micro soldering reagent. Besides, carbon nanotubes (CNTs) have been known that may allow electrons to transport on their surface in a ballistic manner. Despite this, experiments show that multi-wall carbon nanotubes, if without proper ohmic contact, can not conduct electricity. When the both ends of the tested CNTs are soldered with polymeric thionine, significant currents can therefore flow. These results demonstrate that the microsoldering technique proposed in this thesis is useful, showing potential in the development of CNT-based current rectification devices.