Thin-Film Sensors

Abstract

This chapter focuses on potential possibilities of the thin-film sensors based on Thin-film transistors (TFTs) technologies. It introduced a photosensor and temperature sensor as examples of the thin-film sensors. The chapter proposes a p/i/n thin-film phototransistor (TFPT), compares it with other photodevices, characterizes it from the viewpoint of the device behaviour and shows that the p/i/n TFPT is an excellent thin-film photodevice. The p/i/n TFPT is fabricated on a glass substrate using the same fabrication processes as low-temperature poly-Si TFTs. The human eyeballs are curved; the flexible substrate is also preferable. It is possible to make spherical shape by designing a petal-like pattern. As a result, the artificial retinas using TFPTs and TFTs are suitable for the epiretinal implant on the curved human eyeballs. The chapter also focuses on a temperature sensor. It is known that the TFTs have temperature dependence of the current–voltage characteristic.