Integration of MOSFET/MIM Structures Using a CMOS-Based Technology for pH Detection Applications with High-Sensitivity

Chemical and Morphological Characteristics of ALD Al2O3Thin-Film Surfaces after Immersion in pH Buffer Solutions

“…These instabilities are usually related to the degradation of the chemical composition of the sensing layer (typically silicon nitride, Si 3 N 4 ); i.e., oxidation degrades the commonly stable chemical response of the nitride layer to the unstable SiO 2 ; 1 also, hydration of the Si 3 N 4 film could modify its dielectric properties in such a way that a more conductive surface layer is formed 2 and finally, saturation of the film's surface could occur from continuous adsorption of the chemical species of interest. 1 On the other hand, for integration into useful electronic devices, these sensing materials must comply with a fully compatible Complementary Metal-Oxide-Semiconductor (CMOS) fabrication process, so that a low manufacturing cost of the final sensor can be obtained; [3][4][5] as a result, world research efforts are being focused into using novel dielectric materials as sensitive gates for ISFETs like stoichiometric Al 2 O 3 . Although aluminum oxide presents a high sensitivity to pH (close to the ideal Nernstian response), 2,6 neither the degradation mechanisms for an Al 2 O 3 -based ISFET (like sensitivity-drift) nor the initial ability of Al 2 O 3 to give reliable pH measurements with high sensitivity are fully understood.…”

Plant Nutrient Solution Detection System Based on ZigBee Wireless Technology

“…This composite electrode combines the PH indicator electrode and the reference electrode to-Journal of Computer and Communications gether. Its detection temperature range is 5˚C -60˚C, PH measurement range is 0 -14, accuracy is up to 0.01PH, meet the general requirements for PH testing of nutrient solution [11].…”

Study of the Chemical and Morphological Characteristics of Al2O3 and HfO2 Surfaces after Immersion in Time-Dependent pH Solutions

“…These instabilities are usually related to the degradation of the chemical composition of the sensing layer (typically silicon nitride, Si3N4); i.e., oxidation degrades the commonly stable chemical response of the nitride layer to the unstable SiO2 (1); also, hydration of the Si3N4 film could modify its dielectric properties in such a way that a more conductive surface layer is formed (2). Furthermore, for integration into useful electronic devices, these sensing materials must comply with a fully compatible CMOS fabrication process, so that a low manufacturing cost of the final sensor can be obtained (3)(4)(5); as a result, research efforts are focused into using novel dielectric materials as sensitive gates for Ion-Sensors like stoichiometric Al2O3 and HfO2. Although these materials presents a high sensitivity to pH (close to the ideal Nernstian response) (2,6), the degradation mechanisms for a high k-based Ion-Sensor (like sensitivitydrift) are not fully understood (4,7).…”