The design and implementation of a monolithic MEMS-based (Micro Electro Mechanical Systems) gas sensor virtual component is described. A bulk micromachining technique is used to create suspended microhotplate structures. The thermal properties of the microhotplates include a one-millisecond thermal time constant and a 10 'C/mW thermal efficiency. Tin oxide (SnO2) and titanium oxide (TiO2) sensing films are grown over gold sensing electrodes using low-pressure chemical vapor deposition (LPCVD). Gas sensor characterization results are presented showing isothermal response to carbon monoxide molecules with detection sensitivity better than 100 nanomoles/mole.
Citation: Solid-State Electronics
Pub Type: Journals
gas sensor, MEMS, monolithic, SoC, virtual component