Wafer level characterisation of microelectrodes for electrochemical sensing applications

Abstract

Abstract-This work presents a system for the in-line waferlevel characterisation of electrochemical sensors. Typically, such sensors are first diced and packaged before being electrochemically tested. By integrating their characterisation into the manufacturing process, the production of electrochemical sensors becomes more efficient and less expensive as they can be parametrically tested midway through the fabrication process, without the need to package them. This enables malfunctioning or failed devices to be identified before dicing and reduces costs as only functional devices are packaged (in many cases this can be more expensive than the sensor fabrication). This study describes wafer-level characterisation of a simple electrochemical sensor design using a photoresist hydrophobic corralling film for the electrolyte and a probe station for contacting to individual dies.

Recent advances in techniques for fabrication and characterization of nanogap biosensors: A review

“…Prior to applications in biomolecular sensing, electrical characterization of the nanogap electrode is needed to remove ambiguity and to select appropriate electrodes. 169 An electrical test station consists of a probe station with two needles, one representing cathode and another representing anode. 170 An example of electrical characterization using I-V picoammeter equipment (Figure 18).…”

Test structure and measurement system for characterising the electrochemical performance of nanoelectrode structures

“…The design of the liquid delivery system is based upon the approach described in reference [5]. It uses a hydrophobic pattern on a substrate to confine the liquid between it and another parallel plate, in this case a glass slide, and uses capillary action to fill the virtual well.…”

“…This paper describes a nanoelectrode array test structure together with a full characterization system. In its final implementation, such a test structure would be probed at waferlevel, therefore presenting a challenge for a sensor which requires contact with liquid without evaporation [5]. A potential solution could be a confined, thin film of liquid over the surface, which not only prevents evaporation but is more uniform than a droplet.…”