Development of Nano Probes for Electrical Measurement of Biomolecules

We have developed new micromachined opposing nano probes for electrical measurement of biomolecules. Since comb-drive micro actuators were integrated and connected to the nano probes electrically isolated from silicon piece, it will enables us to measure electro-mechanical characteristics of a biomolecule such as piezoelectricity. The probe structure was defined by etching of a 25[μm]-thick silicon-on-insulator wafer (SOI) using an inductively coupled plasma reactive ion etching apparatus (ICP-RIE). To obtain the tip radius of less than 10[nm] and to align two probe tips, new process sequence was designed by combining wet anisotropical etching of silicon with the ICP-RTE. Another type with probes directing outward was also developed.