Optimization of post-deposition annealing temperature for improved signal-to-noise ratio in In2O3 gas sensor

This paper investigates the effects of post-deposition annealing (PDA) temperature on H2S gas sensing and low-frequency noise characteristics of In2O3 gas sensors. In2O3 thin-films are deposited using the radio frequency (RF) sputtering method at an RF power of 150 W and post-annealed at various temperatures (200, 300, and 400 degrees C). The response of the In2O3 gas sensor to H2S decreases with increasing PDA temperature due to the increase of grain size. However, the In2O3 post-annealed at 200 degrees C shows the largest 1/f noise since the damaged sensing material-substrate interface is not fully recovered by the PDA. The sensors post-annealed at a higher temperature (300 degrees C and 400 degrees C) recover the damaged interface. Thanks to its moderate response and noise level, the sensor post-annealed at 300 degrees C shows the largest signal-to-noise ratio.

Automated summary

The effects of post-deposition annealing temperature on In2O3 gas sensors' response to H2S gas and low-frequency noise characteristics were investigated. The sensor annealed at 200 degrees Celsius exhibited the largest 1/f noise, while the sensor annealed at 300 degrees Celsius showed the largest signal-to-noise ratio.