초록

A humidity sensor comprising an insulating substrate, a detection electrodes and a moisture-sensitive layer, wherein the moisture-sensitive layer is a porous layer and has a thickness not greater than 200 μm.

대표청구항 ▼

1. A humidity sensor comprising an insulating substrate, a moisture-sensitive layer, and at least two detection electrodes contacting the moisture-sensitive layer, wherein the moisture-sensitive layer is a porous layer and has a thickness not greater than 200 μm, and each of the detection elec

1. A humidity sensor comprising an insulating substrate, a moisture-sensitive layer, and at least two detection electrodes contacting the moisture-sensitive layer, wherein the moisture-sensitive layer is a porous layer and has a thickness not greater than 200 μm, and each of the detection electrodes comprises a noble metal and is formed of a porous material which has an average pore size greater than that of the moisture-sensitive layer. 2. The humidity sensor according to claim 1, wherein the moisture-sensitive layer has a thickness not greater than 50 μm. 3. The humidity sensor according to claim 1, wherein the detection electrodes comprise a lower electrode and an upper electrode; the lower electrode overlies the insulating substrate; the moisture-sensitive layer overlies the lower electrode such that an entire surface of the lower electrode except the surface covered with the insulating substrate is covered with the moisture-sensitive layer; and the upper electrode overlies the moisture-sensitive layer at a same position with the lower electrode in a laminating direction. 4. The humidity sensor according to claim 1, wherein a planar shape of the detection electrodes is a comblike planar shape; the detection electrodes overlay the insulating substrate; and the moisture-sensitive layer overlies the detection electrodes such that an entire surface of the detection electrodes except the surface covered with the insulating substrate is covered with the moisture-sensitive layer. 5. The humidity sensor according to claim 1, wherein a heater is provided in the insulating substrate. 6. The humidity sensor according to claim 1, wherein a temperature measurement resistor is provided in the insulating substrate. 7. The humidity sensor according to claim 5, wherein the heater is positioned at least partly within a region formed by projecting the moisture-sensitive layer in a laminating direction. 8. The humidity sensor according to claim 6, wherein the temperature measurement resistor is positioned at least partly within a region formed by projecting the moisture-sensitive layer in a laminating direction. 9. The humidity sensor according to claim 1, further comprising a protective coat that covers the detection electrodes and the moisture-sensitive layer, wherein the protective coat comprises one of a metal oxide and a compound oxide. 10. The humidity sensor according to claim 9, wherein the protective coat has a porosity of from 20% to 80%. 11. The humidity sensor according to claim 9, wherein the protective coat has a thickness of from 10 μm to 200 μm. 12. The humidity sensor according to claim 1, wherein the moisture-sensitive layer comprises Al 2 O 3 , TiO 2 and SnO 2 . 13. The humidity sensor according to claim 12, wherein the moisture-sensitive layer has a thickness not greater than 50 μm. 14. The humidity sensor according to claim 12, wherein each of the detection electrodes comprises a noble metal and is formed of a porous material which has an average pore size greater than that of the moisture-sensitive layer. 15. The humidity sensor according to claim 12, wherein the detection electrodes comprise a lower electrode and an upper electrode; the lower electrode overlies the insulating substrate; the moisture-sensitive layer overlies the lower electrode such that an entire surface of the lower electrode except the surface covered with the insulating substrate is covered with the moisture-sensitive layer; and the upper electrode overlies the moisture-sensitive layer at a same position with the lower electrode in a laminating direction. 16. The humidity sensor according to claim 12, wherein a planar shape of the detection electrodes is a comblike planar shape; the detection electrodes overlay the insulating substrate; and the moisture-sensitive layer overlies the detection electrodes such that an entire surface of the detection electrodes except the surface covered with the insulating substrate is covered with the moisture-sensitive layer. 17. The humidity sensor according to claim 12, wherein a heater is provided in the insulating substrate. 18. The humidity sensor according to claim 12, wherein a temperature measurement resistor is provided in the insulating substrate. 19. The humidity sensor according to claim 17, wherein the heater is positioned at least partly within a region formed by projecting the moisture-sensitive layer in a laminating direction. 20. The humidity sensor according to claim 18, wherein the temperature measurement resistor is positioned at least partly within a region formed by projecting the moisture-sensitive layer in a laminating direction. 21. The humidity sensor according to claim 12, further comprising a protective coat that covers the detection electrodes and the moisture-sensitive layer, wherein the protective coat comprises one of a metal oxide and a compound oxide. 22. The humidity sensor according to claim 21, wherein the protective coat has a porosity of from 20% to 80%. 23. The humidity sensor according to claim 21, wherein the protective coat has a thickness of from 10 μm to 200 μm. 24. The humidity sensor according to claim 1, wherein the moisture-sensitive layer has a thickness of from 5 to 50 μm. 25. The humidity sensor according to claim 12, wherein the moisture-sensitive layer has a thickness of from 5 to 50 μm.