Lee Dae-Sik, Yang Haesik, Chung Kwang-Hyo, Pyo Hyeon-Bong
BioMEMS Group, ETRI, P.O. Box 106, Yuseong-Gu, Daejeon 305-350, Korea.
Anal Chem. 2005 Aug 15;77(16):5414-20. doi: 10.1021/ac050286w.
Because of their broad applications in biomedical analysis, integrated, polymer-based microdevices incorporating micropatterned metallic and insulating layers are significant in contemporary research. In this study, micropatterns for temperature sensing and microelectrode sets for electroanalysis have been implemented on an injection-molded thin polymer membrane by employing conventional semiconductor processing techniques (i.e., standard photolithographic methods). Cyclic olefin copolymer (COC) is chosen as the polymer substrate because of its high chemical and thermal stability. A COC 5-in. wafer (1-mm thickness) is manufactured using an injection molding method, in which polymer membranes (approximately 130 microm thick and 3 mm x 6 mm in area) are implemented simultaneously in order to reduce local thermal mass around micropatterned heaters and temperature sensors. The highly polished surface (approximately 4 nm within 40 microm x 40 microm area) of the fabricated COC wafer as well as its good resistance to typical process chemicals makes it possible to use the standard photolithographic and etching protocols on the COC wafer. Gold micropatterns with a minimum 5-microm line width are fabricated for making microheaters, temperature sensors, and microelectrodes. An insulating layer of aluminum oxide (Al2O3) is prepared at a COC-endurable low temperature (approximately 120 degrees C) by using atomic layer deposition and micropatterning for the electrode contacts. The fabricated microdevice for heating and temperature sensing shows improved performance of thermal isolation, and microelectrodes display good electrochemical performances for electrochemical sensors. Thus, this novel 5-in. wafer-level microfabrication method is a simple and cost-effective protocol to prepare polymer substrate and demonstrates good potential for application to highly integrated and miniaturized biomedical devices.
由于其在生物医学分析中的广泛应用，集成有微图案化金属和绝缘层的聚合物基微型器件在当代研究中具有重要意义。在本研究中，通过采用传统半导体加工技术（即标准光刻方法），在注塑成型的薄聚合物膜上实现了用于温度传感的微图案和用于电分析的微电极组。选择环烯烃共聚物（COC）作为聚合物基底，是因为其具有高化学稳定性和热稳定性。使用注塑成型方法制造了一个COC 5英寸晶圆（厚度为1毫米），其中同时制作了聚合物膜（厚度约为130微米，面积为3毫米×6毫米），以减少微图案化加热器和温度传感器周围的局部热质量。所制造的COC晶圆具有高度抛光的表面（在40微米×40微米区域内约为4纳米），以及对典型工艺化学品的良好耐受性，这使得在COC晶圆上使用标准光刻和蚀刻协议成为可能。制作了最小线宽为5微米的金微图案，用于制造微加热器、温度传感器和微电极。通过原子层沉积和电极接触的微图案化，在COC可耐受的低温（约120摄氏度）下制备了氧化铝（Al2O3）绝缘层。所制造的用于加热和温度传感的微型器件显示出热隔离性能得到改善，微电极对电化学传感器显示出良好的电化学性能。因此，这种新颖的5英寸晶圆级微制造方法是一种制备聚合物基底的简单且经济高效的方案，并展示了在高度集成和小型化生物医学器件中的良好应用潜力。
