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In this study we present packaging techniques for SD-card form factor test adapters. Our test adapters consist of FETbased biochemical sensors and a CMOS integrated analog multiplexer connected to a printed circuit board (PCB). Protection of the test adapter is required for long term stability and reliable measurements of the biochemical sensor in a liquid environment. Two different encapsulation techniques and biocompatible materials with different thermomechanical properties were used for this purpose. Adhesive strength measurements of these encapsulants on different substrates were carried out.Finally, the package was integrated into a portable measurement system for multiplexed measurements. Measured gate characteristics were compared between blank and packaged test adapters. FET characteristics were measured in dry as well as in liquid environment.Our packaging technique is mechanically stable, suitable for measurements in liquid environments influences neither the electrical characteristics of the FET devices as nor data acquisition.

The aim of this study is the development of a portable measurement system that simplifies the analysis of bio-sensitive silicon nanowire field effect transistors (SiNW -FETs). In order to obtain the pH -dependent transfer characteristics of the Schottky barrier (SB) FETs, Id = f (Vg), a measurement unit and two biochip adapters are proposed. For the parallel measurement of multiple SiNW -FETs, an integrated CMOS analog multiplexer has been designed, allowing to connect of up to 32 transistors individually. In order to determine the influence of the measurement structure on signal integrity, overall size and system cost, an additional discrete analog multiplexer will be compared with the integrated solution.

In this study we demonstrate the sensing capabilities of a portable multiplex measurement system for FET-based (bio)chemical sensors with an integrated microfluidic interface. We therefore conducted pH measurements with Silicon Nanoribbon FET-based Sensors using different measurement procedures that are suitable for various applications. We have shown multiplexed measurements in aqueous medium for three different modes that are mutually specialized in fast data acquisition (constant drain current), calibration-less sensing (constant gate voltage) and in providing full information content (sweeping mode). Our system therefore allows surface charge sensing for a wide range of applications and is easily adaptable for multiplexed sensing with novel FET-based (bio)chemical sensors.