Development and reliability analysis of micro gas sensor platform on glass substrate

In this paper, technology for a gas sensor platform with borofloat as the substrate material is presented. Comprehensive characterization of the platform, its comparison with silicon and alumina, fabrication yield improvement and a study of reliability of the micro-heater platform have been carried out. Usually, the chips are suspended in air to reduce power consumption. However, the presented technology is a non-MEMS technique and doesn't require any complex packaging. Borofloat has much lower thermal conductivity in comparison to silicon and alumina, thereby reducing the thermal losses, making it possible to operate the device with low power consumption. The process adapted for the fabrication of the gas sensor platform has lesser complexities and the process cost is reduced compared to conventional gas sensor fabrication, as it does not require thermal oxidation and bulk micromachining. Different substrates (silicon, alumina and glass) have been simulated using COMSOL to depict the benefit of lower thermal conductivity. Micro-heater has also been fabricted on all the three above mentioned substrates and the power consumption is compared. Various reliability analysis have been carried out on the glass based platform such as maximum temperature test, long term ON test and ON-OFF pulse test.