title: A zirconium dioxide ammonia microsensor integrated with a readout circuit manufactured using the 0.18 μm CMOS process.
abstract: The study presents an ammonia microsensor integrated with a readout circuit on-a-chip fabricated using the commercial 0.18 μm complementary metal oxide semiconductor (CMOS) process. The integrated sensor chip consists of a heater, an ammonia sensor and a readout circuit. The ammonia sensor is constructed by a sensitive film and the interdigitated electrodes. The sensitive film is zirconium dioxide that is coated on the interdigitated electrodes. The heater is used to provide a working temperature to the sensitive film. A post-process is employed to remove the sacrificial layer and to coat zirconium dioxide on the sensor. When the sensitive film adsorbs or desorbs ammonia gas, the sensor produces a change in resistance. The readout circuit converts the resistance variation of the sensor into the output voltage. The experiments show that the integrated ammonia sensor has a sensitivity of 4.1 mV/ppm.
authors.affiliation: Department of Mechanical Engineering, National Chung Hsing University, Taichung 402, Taiwan. hunter741213@yahoo.com.tw
authors.forename: Guan-Ming
authors.initials: GM
authors.lastname: Lin
authors.forename: Ching-Liang
authors.initials: CL
authors.lastname: Dai
authors.forename: Ming-Zhi
authors.initials: MZ
authors.lastname: Yang
mesh_terms: D000641:Ammonia / Q000737:chemistry*; D004566:Electrodes; D005740:Gases / Q000737:chemistry; D056656:Lab-On-A-Chip Devices; D012666:Semiconductors; D013696:Temperature; D015040:Zirconium / Q000737:chemistry*
chemical_list: D005740:Gases; D000641:Ammonia; D015040:Zirconium; C028541:zirconium oxide