Biochemical sensors with structured and porous silicon capacitors

Chemical sensors with structured and porous semiconductor:insulator capacit ors have been developed. The sensors have been prepared using standard tech niques of semiconductor processing, i.e. by means of an anisotropic and ano dic etching process, respectively. Both sensor types exhibit a high, near-N ernstian pH sensitivity of about 54 mV per pH decade. Due to the enlargemen t of the active sensor area, the measured capacitance values increase up to a factor of 30. These structured and porous electrolyte-insulator-semicond uctor (EIS) sensor substrates are suitable as transducer material for biose nsors which has been demonstrated by depositing the enzyme penicillinase th rough physical adsorption onto the respective pH-sensitive EIS capacitors. (C) 2000 Elsevier Science S.A. All rights reserved.