Low-cost route for the definition of IDE (interdigitated electrode) structures with nanometric geometries over large areas

该项目的目的是提供一种低成本的方法，以制备电极几何尺寸在亚微米和纳米范围内的金属IDE(交指电极)结构，这些电极覆盖毫米范围内的有源区，并通过100微米范围内的接触面积连接电极。尽管这些目标雄心勃勃，但准备工作要尽可能简单和具有成本效益。旋涂、纳米压印、光学光刻和溅射技术将是选择的技术，而不是需要昂贵的高真空设备的电子束写入或干法蚀刻。一种混合技术被应用来进一步简化程序。纳米压印光刻技术(用于定义大面积上的交叉电极)将与光学光刻技术在单个光刻胶层内的简单接触式打印机(用于定义接触区域)中相结合；这两种技术都适用于并行的大面积图案定义。压印过程将以没有残留层的方式进行，使得去除这种层的任何干蚀刻步骤都是多余的。在混合光刻和显影后，直接通过溅射和剥离来制备金属结构。为了进一步促进低成本路线，将只使用容易获得的物品；传统邮票(硅，聚合物复制品邮票)，传统光掩模(石英上的铬，没有相移结构)，传统光致抗蚀剂(负色和正色)以及聚合物基板。金属IDE结构是许多器件的关键部件，这些器件受益于大面积纳米电极；这些器件的范围从简单的(电容或电阻)传感器(例如用于环境应用)到低成本可调的有机DFB(分布式反馈)激光器件(例如用于芯片实验室应用中的生物标记物识别)。低成本的制备路线使这种设备成为一次性、小型化分析系统的有趣之处，特别是在使用塑料衬底的情况下。

This project aims at providing a low-cost route for the preparation of metallic IDE (interdigitated electrode) structures with geometries of the electrodes in the sub-micrometre- and nanometre-range, with active areas covered by these electrodes in the millimetre range and the connection of the electrodes via contact areas in the 100-micrometre range. Though these goals are ambitious, the preparation is to be as simple and as cost-efficient as possible. Spin-coating, nanoimprint, optical lithography and sputtering will be the techniques of choice, and not electron beam writing or dry etching which require costly high-vacuum equipment. A hybrid technique is applied to further simplify the procedure. nanoimprint lithography (for the definition of the interdigitated electrodes over large areas) will be combined with optical lithography in a simple contact printer (for the definition of the contact areas) within one single photoresist layer; both techniques being suitable for parallel, large area pattern definition. The imprint procedure will be conducted in such a way that no residual layer remains, making any dry etch step for the removal of such a layer redundant. Directly after hybrid lithography and development the metallic structures will be prepared by sputtering and lift-off. In order to further foster the low-cost route only items that are easily accessible will be used; conventional stamps (Si, polymeric replica stamps), conventional photomasks (Cr on quartz, no phase shifting structures), conventional photoresists (negative tone and positive tone) as well as polymeric substrates.Metallic IDE structures are the key components for a number of devices that benefit from nanometric electrodes over large areas; these range from simple (capacitive or resistive) sensors (e.g. for environmental applications) to low-cost tunable, organic DFB (distributed feedback) laser devices (e.g. for biomarker recognition in lab-on-chip applications). A low cost preparation route renders such devices interesting for disposable, miniaturised analysis systems, in particular when plastic substrates are used.