An optimum reference detector design for uncooled microbolometer FPAs

Tepegoz, Murat
Civitci, Fehmi
Akın, Tayfun
This paper introduces an optimum reference detector design for uncooled resistive microbolometer focal plane arrays (FPAs). Reference detectors are mainly used for canceling the bias heating and for decreasing the ambient temperature dependence of the system. The proposed method in this paper determines an optimum thermal conductance value for the reference detector such that it is almost infrared blind, but still has the same bias heating characteristics as the active microbolometer detector. Infrared blindness of the reference detector is further increased by covering the top of the detector with an infrared reflective material. An optimum number of reference detectors are determined such that the over-heating of the reference detectors is prevented. Simulation results show that, with the use of the proposed method, it is possible to compensate the resistance change due to bias heating by 87% for the specific case where the detector has 60 k Omega resistance biased at 2 V, 10 ms thermal time constant, and 0.5x10(-7) W/K thermal conductance.


A Two-Stage Digital-to-Analog Converter for Bias Correction in Uncooled Microbolometer Arrays
Toprak, Alperen; Tepegoz, Murat; Akın, Tayfun (2011-04-29)
This paper introduces a detector biasing scheme proper for resistive microbolometer type uncooled thermal detector focal plane arrays (FPAs). The proposed scheme utilizes a 2-stage digital-to-analog converter (DAC) architecture where the first DAC stage generates the voltage interval that covers the bias voltage range of the overall FPA, while the second stage generates the high resolution analog voltages that are used to apply pixel-specific bias voltages. The second DAC stage output includes a resistive l...
An uncooled microbolometer infrared focal plane array in standard CMOS
Tezcan, Ds; Eminoglu, S; Akar, Os; Akın, Tayfun (2001-01-24)
This paper reports implementation of a low-cost microbolometer focal plane array using n-well layer in a CMOS process as the microbolometer material. N-well microbolometer structures are suspended for thermal isolation by postetching of fabricated CMOS dies using silicon bulk-micromachining techniques. Although n-well has a moderate TCR of 0.5-0.65 %/K at 300 K, it still provides a reasonable performance due to its single crystal structure which contributes low 1/f noise. Detailed thermal simulations in ANS...
A CMOS n-well microbolometer FPA with temperature coefficient enhancement circuitry
Eminoglu, S; Tezcan, DS; Akın, Tayfun (2001-04-20)
This paper reports the development of a low-cost CMOS microbolometer focal plane array with a new temperature coefficient enhancement readout circuit. We have recently reported an uncooled microbolometer detector that uses the CMOS n-well layer as the active material, where the suspended and thermally isolated n-well structure is obtained by silicon bulk micromachining of fabricated CMOS dies. In addition, we have successfully fabricated a 16x16 n-well microbolometer FPA. Although n-well is single crystal s...
A Thermal Conductance Optimization and Measurement Approach for Uncooled Microbolometers
Senveli, S. Ufuk; Tanrikulu, M. Yusuf; Akın, Tayfun (2011-04-29)
This paper introduces an optimization approach of thermal conductance for single level uncooled microbolometer detectors. An efficient detector design is required due to the limited availability of silicon area per pixel, i.e., the pixel pitch, and due to the capabilities of the fabrication line. The trade-offs between physical parameters are studied to attain the best performance, including the thermal conductance, the thermal time constant, the effective temperature coefficient of resistance (TCR), and th...
A CMOS current mirroring integration readout structure for infrared focal plane arrays
Külah, Haluk; Akın, Tayfun (1998-09-24)
This paper reports a new, high performance CMOS readout structure, called Current Mirroring Integration (CMI), for high-resolution infrared Focal Plane Array (FPA) applications. Using the integration capacitance outside the FPA, the unit cell area is decreased, making the circuit suitable for high-resolution applications. Moreover, the readout circuit offers high injection efficiency, perfect (almost-zero) detector bias, and large dynamic range in a small pixel area. The circuit provides a maximum charge st...
Citation Formats
M. Tepegoz, F. Civitci, and T. Akın, “An optimum reference detector design for uncooled microbolometer FPAs,” 2008, vol. 6940, Accessed: 00, 2020. [Online]. Available: