Enhanced Visible-Light Response and Optoelectronic Properties of a-IGZO Phototransistors with Dye and PMMA Blend Heterojunctions

This study presents a hybrid phototransistor that combines amorphous-InGaZnO (a-IGZO), a widely studied metal oxide semiconductor in the display industry, with an organic layer composed of dyes and PMMA. In this device, a-IGZO functions as the conducting channel, while the organic layer serves as a visible-light absorption layer. This heterojunction structure overcomes the limitations of a-IGZO phototransistors, which have restricted visible-light detection due to their wide bandgap (3.73 eV) and enables superior photoresponse to visible wavelengths. Furthermore, the device demonstrates tunable light detection wavelengths depending on the type of dye used as well as controllable optoelectronic properties by adjusting the structure of the light-absorption layer. This work provides an analysis of the operating mechanism of the hybrid phototransistor responsive to visible light and explores its potential applications in neuromorphic technologies.