Microsystems for biochemical applications based on CVD diamond

In biochemistry, microsystems become more and more attractive. Presently they are built around capillary assemblies and reaction substrates. However, in the future, integration with active devices like actuators and sensors will become increasingly important. Diamond CVD films possess attractive features for many of the building blocks needed in such a "lab on a chip" system. In fact it is the only material which can be insulating, semiconducting or metal-like and is at the same time inert and stable within the entire range of chemicals in question. In this study two important key elements have been investigated: (1) CVD diamond films as inert electrode and FET structures with electrolyte gate, representative for many applications such as pH-sensing, and (2) a generic microreactor module with a digital inkjet dispenser with 4 pl-resolution. This device has been designed for oligonucleotide synthesis and its critical performance characteristics are demonstrated.