Evaluation of pH sensors using self-aligned four-terminal planar embedded metal double-gate low-temperature polycrystalline-silicon thin-film transistors on glass substrate

This study presents an evaluation of pH sensors using self-aligned four-terminal planar embedded metal double-gate low-temperature polycrystalline-silicon thin-film transistors (TFTs) on a glass substrate. The voltage variation due to a change in pH is read as the variation in threshold voltage of the TFTs by connecting a TFT control gate to a glass electrode. Our experimental results confirm that these TFTs can be successfully used as pH sensors.