A low-cost 64x64 uncooled infrared detector array in standard CMOS

Eminoglu S., Tanrikulu M., Akin T.

12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03), Massachusetts, United States Of America, 8 - 12 June 2003, pp.316-319 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Doi Number: 10.1109/sensor.2003.1215316
  • City: Massachusetts
  • Country: United States Of America
  • Page Numbers: pp.316-319
  • Middle East Technical University Affiliated: Yes


This paper reports the development of a low-cost, 64 x 64 uncooled infrared focal plane array (FPA) based on suspended and thermally isolated p(+)-active/n-well diodes in a standard 0.35 mum CMOS process. The array is implemented using a simple post-CMOS process that do not require any critical lithography or complicated deposition steps. The pixel is 40 mum x 40 mum in size with a fill factor of 44%, and it has a measured DC responsivity of 4970 V/W with a thermal time constant of 36 msec at 80 mToff vacuum. The detector noise is measured as 0.52 muV for a 4 kHz electrical bandwidth with a 1/f corner frequency of 4.4 Hz, resulting in a measured detectivity of 9.7 x 10(8) cmHz(1/2)/W and an estimated NETD value of 470 mK for an f = 1 optics. The FPA is scanned at 30 fps using a 16-channel parallel readout circuit with low noise preamplifiers. The preampliers have a measured noise of 0.48 muV, resulting in an overall estimated NETD of 800 mK, which can be decreased by increasing the number of parallel readout channels. The uncompensated pixel voltage non-uniformity is measured as 0.82%, which easily decreases down to 0.05% by compensating the fixed pattern noise. Considering its simple fabrication method and its moderate performance, this approach is suitable for low-cost commercial infrared imaging applications.