TY - JOUR A1 - Schöning, Michael Josef A1 - Simonis, Anette A1 - Ruge, Christian A1 - Ecken, Holger A1 - Müller-Veggian, Mattea A1 - Lüth, Hans T1 - A (bio-)chemical Field-effect Sensor with Macroporous Si as Substrate Material and a SiO₂ / LPCVD-Si₃N₄ Double Layer as pH Transducer JF - Sensors. 2 (2002), H. 1 N2 - Macroporous silicon has been etched from n-type Si, using a vertical etching cell where no rear side contact on the silicon wafer is necessary. The resulting macropores have been characterised by means of Scanning Electron Microscopy (SEM). After etching, SiO₂ was thermally grown on the top of the porous silicon as an insulating layer and Si₃N₄ was deposited by means of Low Pressure Chemical Vapour Deposition (LPCVD) as transducer material to fabricate a capacitive pH sensor. In order to prepare porous biosensors, the enzyme penicillinase has been additionally immobilised inside the porous structure. Electrochemical measurements of the pH sensor and the biosensor with an Electrolyte/Insulator/Semiconductor (EIS) structure have been performed in the Capacitance/Voltage (C/V) and Constant capacitance (ConCap) mode. Y1 - 2002 SN - 1424-8220 U6 - http://dx.doi.org/10.3390/s20100011 SP - 11 EP - 22 ER -