High performance read-out IC design for IR image sensor applications

Abstract

In this paper, high performance read-out integrated circuits (ROIC) for infrared (IR) image sensor applications is proposed. Because an uncooled microbolometer image sensor, used in an IR image sensor, is made by a micro electro mechanical systems process, the resistance of bolometer by each process does not appear same value under same temperature condition. This resistance variation generates a different output signal for same input by each chip. In order to improve on these drawbacks, a ROIC, which compensates for the error described above, was designed. Instead of a single input mode, a differential input mode ROIC was proposed and thus, a new circuit structure was proposed. Using results from a computer simulation, improvements such as that the effect of the process error was decreased 10-12% without an additional compensation circuit was found. Based on the simulation results, a prototype device including a ROIC and a micro bolometer with 16 9 16 cell arrays was fabricated and characterized.

Simulation and Analysis of Uncooled Microbolometer for Serial Readout Architecture

“…2 Journal of Sensors Microbolometer detector arrays are fabricated using the microelectromechanical systems (MEMS) technology [5,9]. Due to the variability within the material and process, each fabricated microbolometer has a different nominal resistance value corresponding to the same infrared radiation that introduces the FPN in detector arrays [1,2,10].…”