Title :
Influence of the gate insulator on gas measurements with suspended gate FETs
Author :
Topart, F. ; Flietner, B. ; Josowicz, M. ; Leu, M. ; Lorenz, H. ; Peschke, M. ; Riess, H. ; Eisele, I.
Author_Institution :
Inst. fur Phys., Univ. der Bundeswehr Munchen, Neubiberg, Germany
Abstract :
An attempt is made to separate the relative contributions to the threshold voltage shift of the layers composing a suspended gate FET (SGFET). For that purpose the insulators silicon nitride and diamondlike (a-C:H) films, as well as the sputtered SnO/sub 2/ and Ti/W, active layers have been investigated. The gas-surface interaction has been characterized by carrying out simultaneous measurements of mass changes (quartz crystal microbalance) and work function shifts (Kelvin probe). It is shown that the threshold voltage shift of SGFETs, composed of various insulator/active layer combinations, is a superposition of the independently measured work function shifts.<>
Keywords :
adsorption; electric sensing devices; gas sensors; insulated gate field effect transistors; work function; NH/sub 3/ adsorption; SiO/sub 2/-Si/sub 3/N/sub 4/ sandwich; Ti-W films; amorphous C:H films; gas sensors; gas-surface interaction; gate insulator influence; insulator/active layer combinations; mass changes; sputtered SnO/sub 2/ films; suspended gate FET; threshold voltage shift; work function shifts; Chemical vapor deposition; FETs; Gas detectors; Gas insulation; Humidity; Kelvin; Probes; Semiconductor films; Silicon; Threshold voltage;
Conference_Titel :
Solid-State Sensors and Actuators, 1991. Digest of Technical Papers, TRANSDUCERS '91., 1991 International Conference on
Conference_Location :
San Francisco, CA, USA
Print_ISBN :
0-87942-585-7
DOI :
10.1109/SENSOR.1991.149058
