Nanocrystalline Cerium Oxide Films for Microelectronic Biosensor Transducers

Abstract

The physical properties of thin nanocrystalline cerium oxide films have been studied with the purpose of their application as a functional material of different microelectronic transducers for biosensors: highperformance photoresistors and photodiodes for bioluminescence registration, ion-selective field-effect transistors (ISFET) and MOS-varactors indicating the pH changes as a result of biochemical processes. The effect of technological factors on the photoelectrical, optical, temperature and electrophysical properties of cerium oxide films has been studied. We established the technological conditions which allow to obtain СеОх-films with desired functional characteristics. On the basis of the synthesized nanocrystalline СеОх-films obtained by the "explosive evaporation" method we developed new types of photodetectors for registration of bioluminescent signal (photoresistors and photodiodes) with enhanced photosensitivity (310- 330 mA/lm∙V) in the visible range. Application of cerium oxide based photoresistors in the bioluminometers instead of photomultiplier tubes and avalanche photodiodes allows to significantly reduce the cost of bioluminometer and increase its sensitivity when measuring at alternating signal. On the basis of nanocrystalline СеОх-films obtained by the "metallic mirrors oxidation" method we developed potentiometric biosensory transducers (ion-selective field-effect transistors and MOS-varactors) with CeOx as gate dielectric. It yields higher sensitivity and stability as compared to the use of the SiO2 and Si3N4 films. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/34964