Hydrogen Sensing Mechanisms of Metal−Insulator Interfaces

Abstract

Lars-Gunnar Ekedahl (formerly Petersson) was born in 1947 in Kalmar, Sweden. He received a B.Sc. (1972) and a Ph.D. (1977) in physics from Linko ¨ping University. He became a Professor of surface chemical physics in Linko ¨ping (1993). He is also the program director of a new multidisciplinary graduate school, Forum Scientum, located at Linko ¨ping University. From 1981 his research has been focused on kinetics of surface reactions and catalysis, particularly with applications toward chemical sensing with MOS devices. Both modeling and experimental studies utilizing surface science oriented methods have been performed. At present Ekedahl heads a research group studying fundamental heterogeneous catalysis, from ultrahigh vacuum up to atmospheric pressures.Mats Eriksson was born in 1963 in Stockholm, Sweden. He received a M.Sc. in 1987 and a Ph.D in 1997 from Linko ¨ping University. He has studied fundamentals of hydrogen sensing with Pd-MOS structures in ultrahigh vacuum. He has studied adsorption processes and catalytic reactions on catalysts with different degrees of dispersion. He has also performed kinetic modeling of catalytic reactions.

CMOS Single Chip Gas Detection Systems — Part I

“…Hydrogen molecules readily absorb on the gate metal (platinum, iridium, palladium) and dissociate into hydrogen atoms. These H-atoms can diffuse rapidly through the Pd and absorb at the metal/silicon oxide interface partly on the metal and partly on the oxide side of the interface [77,78]. Owing to the absorbed species and the resulting polarization phenomena at the interface, the threshold voltage (U d ) is shifted.…”

“…Applications also include the detection of ammonia [77,78], amines and any kind of molecule that gives rise to polarization in a thin metal film (hydrogen sulfide, ethene, etc.) or causes charges/dipoles on the insulator surface [77,78]. iliary sensors such as temperature sensors are needed to deal with cross-sensitivities of the sensing device.…”

SiC-based MIS gas sensor for high water vapor environments

“…Nevertheless, its high chemical inertness, its physical resistance and its high thermal conductivity make of SiC a semiconductor suitable for harsh environmental applications. According to most accepted model for the sensing mechanism of MIS hydrogen sensors the changes in the electrical characteristics of the devices are due to the formation of H-induced dipole layer at the metal-oxide interface [1,[14][15][16][17][18]. The hydrogen gas molecules are dissociatively adsorbed at the surface of the catalytic gate and then the atomic hydrogen diffuses quickly toward the metal-oxide interface through the dense metallic layer.…”

Remote sensing system for hydrogen using GaN Schottky diodes

“…In addition, these detectors would have dual-use in automobiles and aircraft, fire detectors, exhaust diagnosis and emissions from industrial processes [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. The high-temperature capabilities of GaN electronics and sensors will reduce spacecraft launch weighs and increase satellite functional capabilities.…”