摘要
Au fiber disk microelectrodes with well defined geometries were fabricated by low temperature plasma enhanced chemical vapor deposition（PECVD）.Silicon nitride thin films with thickness of 0.7 μm were deposited concentrically on the cylindrical length of 25 μm Au fibers.To form microelectrodes devices,the coated gold microfibre was connected to a copper leader with Ag epoxy.The thin film deposition was performed in a PECVD instrument with substrate temperature（340±10） ℃.Comparing with chemical vapor deposition and resistive heating（CVD-RH）,the insulation by the PECVD can be performed to metal microfibres with the low melting or softening points for the fabrication of microelectrodes as it offers the possibility to fabricate a surface coating at low temperature（≤450 ℃）.The quality,thickness and adhesion to the fiber substrates of films were characterized by scanning electron microscopy.The films are found to be free of microcracks and have a quality seal with Au fibers.Cyclic voltammograms were obtained in electrolyte of 0.5 mmol/L K3Fe3（CN）6 in 0.5 mol/L KCl solution.The electrochemical responses are sigmoidal in shape and indicate that the radial diffusion is the primary mode of mass transport at different scan rates.As a result,the silicon nitride coated disk microelectrodes exhibit an excellent microelectrode electrochemical response without using an epoxy sealant.
Au fiber disk microelectrodes with well defined geometries were fabricated by low temperature plasma enhanced chemical vapor deposition（PECVD）. Silicon nitride thin films with thickness of 0.7μm were deposited concentrically on the cylindrical length of 25μm Au fibers. To form microelectrodes devices, the coated gold microfibre was connected to a copper leader with Ag epoxy. The thin film deposition was performed in a PECVD instrument with substrate temperature （340±10）℃. Comparing with chemical vapor deposition and resistive heating （CVD-RH）, the insulation by the PECVD can be performed to metal microfibres with the low melting or softening points for the fabrication of microelectrodes as it offers the possibility to fabricate a surface coating at low temperature （≤450℃）. The quality, thickness and adhesion to the fiber substrates of films were characterized by scanning electron microscopy. The films are found to be free of microcracks and have a quality seal with Au fibers. Cyclic voltammograms were obtained in electrolyte of 0. 5 mmol/L K3 Fe3 （CN） 6 in 0.5 mol/L KCl solution. The electrochemical responses are sigmoidal in shape and indicate that the radial diffusion is the primary mode of mass transport at different scan rates. As a result, the silicon nitride coated disk microelectrodes exhibit an excellent microelectrode electrochemical response without using an epoxy sealant.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2006年第2期233-235,共3页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:2003CB716201
2003CB716203)资助
关键词
金微盘电极
等离子增强化学气相沉积
氮化硅
循环伏安法
扫描电子显微镜
Au disk microelectrodes
Plasma enhanced chemical vapor deposition
Silicon nitride
Cyclic voltammetry
Scanning electron microscopy
