Back to results
US 4,638,346 AGranted
Field effect transistor-type moisture sensor
AssigneeSharp Kabushiki Kaisha
InventorsYasuhiko Inami, Masanori Watanabe, Masaya Hijikigawa
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeSharp Kabushiki Kaisha
InventorsYasuhiko Inami, Masanori Watanabe, Masaya Hijikigawa
Estimating the term…
A field effect transistor-type moisture sensor comprising a field effect transistor device incorporated with a moisture sensitive means, the electrostatic capacity or the electrical conductivity of which varies with the absorption and the desorption of water vapor or moisture, wherein said moisture sensitive means is disposed on a gate insulating film of said field effect transistor device to form an electrode structure, said moisture sensitive means being a film prepared by cross-linking cellulose acetate butyrate with at least one selected from the group consisting of compounds containing two or more isocyanate groups; compounds containing two or more epoxy groups; compounds containing two or more carboxylic acid groups; and acid anhydrides of carboxylic acids.
A field effect transistor-type moisture sensor comprising a field effect transistor device incorporated with a moisture sensitive means, the electrostatic capacity or the electrical conductivity of which varies with the absorption and the desorption of water vapor or moisture, wherein said moisture sensitive means is disposed on a double-layered gate insulating film of said field effect transistor device, a gate electrode is connected to said moisture sensitive means, an auxiliary electrode for the application of a drift-cancellation voltage to said moisture sensitive means is located at the interface between said gate insulating film and said sensitive means, and said moisture sensitive means is a film prepared by cross-linking cellulose acetate butyrate with at least one compound selected from the group consisting of compounds containing two or more isocyanate groups, compounds containing two or more epoxy groups, compounds containing two or more carboxylic acid groups, and acid anhydrides of carboxylic acids.
A MIS-field effect transistor type moisture sensor comprising a field effect transistor device incorporated with a moisture sensitive means, the electrostatic capacity or the electrical conductivity of which varies with the absorption and the desorption of water vapor or moisture, wherein said moisture sensitive means is disposed on a gate insulating film of said field effect transistor device, a gate electrode for the field effect transistor is disposed on the outer surface of said moisture sensitive means, an auxiliary electrode for the application of a drift-cancellation voltage to said moisture sensitive means is located at the interface between said gate insulating film and said moisture sensitive means, and said moisture sensitive means is a film prepared by cross-linking cellulose acetate butyrate with at least one compound selected from the group consisting of compounds containing two or more isocyanate groups, compounds containing two or more epoxy groups, compounds containing two or more carboxylic acid groups, and acid anhydrides of carboxylic acids.
A field effect transistor-type moisture sensor comprising in combination:
Dependencies are inferred from the claim text.