针对非制冷红外探测器系统,设计了一种无需衬底温度稳定器——热电制冷器(TEC)的读出电路(ROIC)结构.首先分析了衬底温度对微测辐射热计的特性的影响,利用ROIC对衬底温度变化引起的微测辐射热计的特性的变化进行补偿,实现ROIC的输出信号与衬底无关.该ROIC已在0.5gmCMOS工艺下成功流片,并应用了到阵列大小为320×240的非制冷微测辐射热计焦平面上.测试结果表明:在衬底温度变化20K时,ROIC输出信号仅变化2mV,实现了去除TEC后衬底温度补偿的功能,有效地降低了系统功耗.该ROIC在低功耗,小体积的非制冷红外探测器上有着广泛的应用.
A new read-out IC (ROIC) architecture with substrate temperature compensation was introduced for the un- cooled microbolometer detector. The influence of responsivity on the substrate temperature was evaluated. Numerical simulation and measurement of the proposed ROIC architecture demonstrated high quality of signal over wide temperature range without using multiple corrections. A 320 x 240 uncooled microbolometer focal plane array(FPA) based on the proposed circuit was implemented on silicon using a 0.5 Ixm CMOS technology. The measurement data show that the maximum difference of the output voltages is only 2mV over the change of 20K in the substrate temperature. This archi- tecture is expected to allow removal of the thermoelectric cooler (TEC) from uncooled systems. Thus it is ideally suited for low-cost, low-power, and low-weight production applications.