Lab-on-a-chip or μ-TAS (micro-total analysis systems) are portable and cost-effective devicescombining fluid-handling, detection and data interpretation. In μ-fluidic applications polymers have distinct advantages over Si or glass devices including broad materials selection, cost effectiveness, disposability,bio-compatibility, chemical resistance and easy process-ability. In order to realize miniaturized integrated systems with these materials new fabrication and packaging techniques have evolved.This work is focused on low temperature packaging of nano/micro structured polymers using plasma activated low temperature direct bonding techniques. Nano/micro structured polymer devices, structured by NanoImprint Lithography (NIL) [1], can be heterogeneously (polymer to glass or Si) or homogeneously (polymer to polymer) bonded. To improve the physical and chemical fusion of the bond materials, the bonding step usually uses high temperatures near the glass transition temperature of the polymer.Unfortunately high temperatures degrade fine features, especially for high aspect ratio structures.Plasma activation of the polymer in the EVG(R) 810LT plasma chamber uses a soft RF frequency plasma surface treatment, which cleans and activates the top layers without changing the bulk properties of the polymers. Finally, the two activated surfaces are joined together in an EVG(R) 501 wafer bonder by applying a modest and uniform contact force at low temperatures, ensuring hermetic sealing of the cavities and preventing destruction or distortion of small features. Vacuum conditions of atmosphere to 200～1 000 Pa, contact forces of 2～5 kN and temperature of RT to 80 ℃ were used in the bonding study.%Lab-on-chip或μ-TAS(micro-total analysi s systemS)结合流体处理、检测及数据分析,是一种便携式的低成本高效器件.在微流体应用中,聚合物具有比硅或玻璃器件更明显的优势,它包括:宽泛的材料选择性,成本低、效率高,使用任意性,生物兼容性,抗化学品和工艺灵活性.为了实现采用这类材料制备小型集成化系统,我们发展了新的制备与封装技术.这项工作着眼于运用等离子体活化低温直接键合技术实现纳/微结构聚合物在低温条件下进行封装.由纳米压印光刻制作的纳/微结构的聚合物器件,可能是异质(聚合物与玻璃或硅)或同质(聚合物与聚合物)键合.为了改进键合材料的物理和化学熔合,键合工序通常在接近聚合物的玻璃化转变温度的高温下进行.但遗憾的是,高温损伤了微细图形,特别是对于高深宽比结构.在EVG(R)810LT等离子体反应室里,我们采用软射频频率等离子体表面处理,来进行聚合物的等离子体活化,它能在不改变聚合物体特性的前提下清洗和活化聚合物顶层.最终结果是,在EVG(R)501晶圆键合机上,两个活化的表面在低温下通过施加一个适中的、均匀的接触压力而连接在一起,保证了空腔密封并防止了小结构的破坏和变形.键合工艺条件为:真空条件为从大气到200～100O Pa、接触压力为2～5kN、温度从室温到8 0℃.
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