在模拟的空间环境试验中测试了锰钴镍型红外探测器的电阻值和低频噪声参量.采用钴-60源分别在10 rad(si)/s和0.1 rad(si)/s的剂量率下对两组样品累积辐照到总剂量150 krad(si), 结果表明：在0.1rad(si)/s剂量率下探测器低频噪声退化量远大于10 rad(si)/s剂量率下的低频噪声退化量.对第三组样品先后施加了三种热应力, 即无偏热应力(40℃, 保持4h), 加偏热应力(偏置电压±15 V, 40℃, 保持600 h)和无偏热循环(－40℃到40℃, 温度变化率1℃/s, 峰值温度保持1 h, 20个循环), 结果表明：热应力试验中, 样品电阻值变化规律相对一致, 但低频噪声的退化趋势存在明显差异, 且失效探测器表现为低频噪声突然增大.分析表明, 无偏热应力与加偏热应力引起的低频噪声退化来源于电阻薄片内部的缺陷, 而热循环导致的低频噪声退化来源于连接Pt引线焊点接触处的潜在缺陷.研究发现噪声系数是锰钴镍型红外探测器低频噪声退化的敏感参量, 热应力与热循环则可以有效甄别该类器件噪声退化.

Electrical resistance and low-frequency noise of Mn-Co-Ni type infrared detectors were measured during space-simulated environment experiments. Two groups of samples were irradiated up to 150 krad(si) accumulated dosage with a cobalt-60 source at dose rate of 10 rad(si)/s and 0.1 rad(Si)/s), respectively. The results show that 1/f noise increased significantly at dose rate of 0.1rad(Si)/s, but almost unchanged at dose rate of 10 rad(Si)/s. Three thermal stresses, namely, short-term thermal burn-in without bias (40℃, hold for 4 h), extended thermal brun-in with DC bias (bias voltage of ±15 V, 40℃, hold for 600 h) and thermovacuum cycling (－40℃ to +40℃, 1℃/min, hold for 1 h, 20 cyclings), were successively applied to a third group of samples, the changes of electrical resistance of samples have similar behavior; however, the degradation of 1/f noise shows different trends, and all malfunctions present abrupt increment. Theoretical analysis shows that the degradations of 1/f noise during the short-term thermal burn-in and extended thermal burn-in with DC bias may be ascribed to the defects within the thermistor bulk, and the degradations of 1/f noise during thermal cycling may be ascribed to the defects at the contacts. These results suggest that noise figure is a sensitive parameters for describing the low-frequency noise degeneration of infrared detectors, and short-term thermal burn-in and thermal cycling are effective testing methods for discriminating 1/f noise of infrared detectors.