초록 ▼

Methods of and systems providing high reliability relative humidity sensors having integrated signal conditioning are described, providing a series capacitive circuit including a humidity-sensitive dielectric, a common top plate and first and second bottom plates associated with a first and second c

Methods of and systems providing high reliability relative humidity sensors having integrated signal conditioning are described, providing a series capacitive circuit including a humidity-sensitive dielectric, a common top plate and first and second bottom plates associated with a first and second capacitor, respectively. Changes in humidity affect the humidity-sensitive dielectric thereby causing changes in the capacitive value of said series capacitive circuit. The system includes a common top plate; a common humidity-sensitive dielectric formed under said common top plate; a first series capacitor Cx1 including a first bottom plate formed under said common humidity-sensitive dielectric opposite said common top plate; a second series capacitor Cx2 including a second bottom plate formed under said common humidity-sensitive dielectric opposite said common top plate; wherein said first series capacitor Cx1 and said second series capacitor Cx2 commonly share said dielectric and commonly share said common top plate and are arranged in a series capacitor circuit configuration within a semiconductor system. A sampling voltage source can provide a fixed voltage through said series capacitive circuit.

대표청구항 ▼

1. A semiconductor-based humidity sensor, comprising: a substrate;a first insulator layer formed on said substrate;a first capacitor plate formed on said first insulator layer;at least one first contact associated with said first capacitor plate formed on said first insulator layer;a second capacito

1. A semiconductor-based humidity sensor, comprising: a substrate;a first insulator layer formed on said substrate;a first capacitor plate formed on said first insulator layer;at least one first contact associated with said first capacitor plate formed on said first insulator layer;a second capacitor plate formed on said first insulator layer;at least one second contact associated with said second capacitor plate formed on said first insulator layer;an electrically insulative barrier formed in a gap between said first capacitor plate and said second capacitor plate, wherein said first capacitor plate and said first contact and said second capacitor plate and said second contact define a first stray capacitor;a humidity-sensitive dielectric layer formed on said first insulator layer, said first capacitor plate and said second capacitor plate; anda porous, electrically-conductive plate formed on said humidity-sensitive dielectric, wherein said porous, electrically-conductive plate is a common top plate to said first and second capacitor plates of a respective first series capacitor Cx1 and second series capacitor Cx2.2. The invention of claim 1, wherein said humidity-sensitive dielectric layer includes a polyimide material, which changes its dielectric constant with changes in humidity as sensed through said porous, electrically-conductive plate.3. The invention of claim 1, further comprising:a source of sampling potential; andmeans for detecting change in capacitive value of said series capacitive circuit configuration.4. The invention of claim 3 further comprising a reference capacitor whose dielectric does not change with changes in humidity.5. The invention of claim 3 wherein said means for detecting change in capacitive value of said series capacitive circuit configuration includes an indicator for indicating the humidity measured.6. The invention of claim 1 wherein said substrate is a semiconductor.7. The invention of claim 1 wherein said humidity-sensitive dielectric layer comprises a moisture sensitive porous dielectric film.8. The invention of claim 1 further comprising a humidity-sensitive dielectric layer formed on said porous, electrically-conductive plate for covering and protecting said porous, electrically-conductive plate and said humidity-sensitive dielectric layer from exposure to non-vaporous contaminants.9. The invention of claim 1 wherein said porous, electrically-conductive plate comprises a conductive polymer film.10. The invention of claim 1 wherein said porous, electrically-conductive plate is moisture permeable.11. The invention of claim 1 wherein said porous, electrically-conductive plate comprises platinum.