A 256 × 256, 50-μm Pixel Pitch OPD Image Sensor Based on an IZO TFT Backplane

This paper proposes an organic photodiode (OPD) image sensor based on indium zinc oxide (IZO) thin-film transistors (TFTs). The sensor array has a 256 × 256 pixel format with a 50 μm pixel size. The continuous OPD fabricated by the solution process is stacked vertically on the top of the IZO TFT backplane. A measurement system is built based on the readout IC driven by the field programmable gate array (FPGA). It is shown that the optical image can be successfully detected by the sensor array with good clarity and high quality. With a leakage current of the IZO TFT as low as 5×10 ^-14 A and a dark current of OPD as low as 10 ^-13 A, the total electronic noise is less than 683 e ^- .