Thin-Film Transistor Pixel Circuits for Image Sensor
Geonwook Yoo, Gwanghyeon Baek and Jerzy Kanicki
Image sensor usually contains optical lens assembly and photo-sensing chips. Due to the limitation of the processing capability, image sensors currently rely on chips built on the planar surface. This approach, however, requires complicate lens system and makes high performance image sensor inevitably bulky. In this project, we expect to be able to achieve high performance image sensor with wider field-of-view by building the thin-film transistor circuitry (or backplane) and photo-sensing element on a hemispherical surface.
We have investigated passive and active pixel circuit designs with various TFT structures developed in our group, and their performance has been studied using HSPICE simulations. Below is the schematics of the simulated result of the passive pixel sensor (PPS). Also, innovate fabrication methods on non-planar surface are under development. This work is supported by DARPA/MTO.
Image sensor usually contains optical lens assembly and photo-sensing chips. Due to the limitation of the processing capability, image sensors currently rely on chips built on the planar surface. This approach, however, requires complicate lens system and makes high performance image sensor inevitably bulky. In this project, we expect to be able to achieve high performance image sensor with wider field-of-view by building the thin-film transistor circuitry (or backplane) and photo-sensing element on a hemispherical surface.