Patterning of platinum microelectrodes in polymeric microfluidic chips
Patterning of platinum microelectrodes in polymeric microfluidic chips
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DOI：
10.1117/1.2242633
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发表时间：
2006-07-01
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影响因子：
--
通讯作者：
Dutta, Prashanta
中科院分区：
文献类型：
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作者：
Al Mamun, Nazmul Huda;Dutta, Prashanta
微型电极是用于分离、泵送、传感和其他生物分析的“芯片实验室”设备的最重要组件之一。在基于微流体的化学和生物分析操作中，铂电极由于其化学惰性而优选用于最小化与化学品或生物分子的相互作用。虽然用于在硅、石英或玻璃衬底上图案化集成铂微电极的微制造技术是可用的，但是迄今为止还没有报道用于在软聚合物微通道中沉积铂电极的技术。提出了一种在聚二甲基硅氧烷（PDMS）微芯片中形成集成微电极的新方法。电极制作技术包括光刻、热处理、钛和铂的顺序溅射以及剥离光致抗蚀剂，而软光刻用于在PDMS上形成微流体通道。这种方法有助于电极之间具有微米尺寸间隙的精确定位，并且它可以用于低纵横比通道和高纵横比通道。由于在铂和PDMS之间使用了非常薄的钛层，在PDMS通道表面上形成的铂电极表现出与基底非常好的界面粘附。溅射电极具有50 nm的表面粗糙度，并且能够感测通过苯的皮安级电流。(C)2006年，由光学仪器工程师协会（Society of Photo-Optical Instrumentation Engineers）主办。
Miniaturized electrodes are one of the most important components of "lab-on-a-chip" devices for separation, pumping, sensing, and other bioanalyses. In microfluidic-based chemical and bioanalytical operations, platinum electrodes are preferred to minimize the interaction with chemicals or biomolecules due to their chemical inertness. Although microfabrication techniques for patterning integrated platinum microelectrodes on silicon, quartz, or glass substrates are available, no techniques have been reported so far for depositing platinum electrodes in soft polymeric microchannels. A novel fabrication scheme is described for forming integrated microelectrodes in a poly-dimethylsiloxane (PDMS) microchip. The electrode fabrication technique consists of photolithography, thermal processing, sequential sputtering of titanium and platinum, and stripping off photoresist, while soft lithography is used to form the microfluidic channels on PDMS. This approach facilitates precise positioning of the electrodes with a micron-size gap between them, and it can be used for both low and high aspect ratio channels. Platinum electrodes, formed on the PDMS channel surface, demonstrate very good interfacial adhesion with the substrate due to the use of a very thin titanium layer between the platinum and PDMS. The sputtered electrodes have a surface roughness of 50 nm and are able to sense picoA level current through benzene. (C) 2006 Society of Photo-Optical Instrumentation Engineers.