SiNx/SiO2 Stacked Sensitive Thin Film for ISFET-based Chemical and Biochemical Sensors - Preparation and Characterization of the Stacked Thin Films and Sensors

In this work, nitrogen rich SiNx thin film was deposited on SiO2/p-Si (100) substrate by low pressure chemical vapour deposition (LPCVD). The film was physically characterized using techniques such as Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM) and ellipsometry. The biocompatibility of such film was investigated by FTIR. Using a set of metal insulator semiconductor field effect transistors (MISFETs) and ion sensitive field effect transistors (ISFETs) fabricated, electrical characteristics and sensing properties were investigated. The biocompatibility of the SiNx film and the electrical quality of the SiNx/SiO2/p-Si interface obtained suggests that SiNx/SiO2 is an adequate insulator on ISFET based chemical and biochemical sensors.