有Al激光器和无Al激光器的工作寿命对比研究

为了证明无Al激光器在可靠性方面优于有Al激光器,对InGaAsP/GaAs无Al和AlGaInAs/AlGaAs/GaAs有Al的808nm大功率半导体激光器进行了常温下电流步进加速老化寿命试验,介绍了半导体激光器寿命试验的理论依据,给出寿命试验的数学模型,据此得到了器件在常温电流步进条件下的寿命,利用最小二乘法拟和得到加速老化的加速方程,从而推算出激光器的特征寿命,分析了有Al激光器和无Al激光器寿命对比结果,提出了材料中含Al对器件可靠性的一些不良影响,无Al激光器可靠性明显优于有Al激光器.     

大功率半导体激光器的可靠性研究

文中介绍了半导体激光器寿命测试的理论依据,给出寿命测试的数学模型,据此对InGaAsP/GaAs有源区无铝的808nm大功率半导体激光器进行高温恒流加速老化实验,得到器件在高温下的寿命,利用外推公式推算出激光器在室温条件下工作的寿命可超过30000小时。讨论了实验中出现的灾变退化,提出了防止灾变退化的几种方法。     

808 nm大功率半导体激光器的加速老化实验

对InGaAsP/GaAs有源区无铝的808 nm大功率半导体激光器进行了高温恒流加速老化实验,得到了器件在高温条件下的寿命,利用外推公式推算出激光器在室温条件下工作的寿命可超过30000 h.讨论了实验中出现的灾变退化现象,提出了防止灾变退化的几种方法.     

半导体激光器加速寿命测试系统研制

介绍了半导体激光器(LD)加速寿命测试的理论依据,给出了寿命测试的数学模型,并据此研制了新型LD寿命测试系统。该系统在密封抽真空充氮环境下,通过采集恒功工作LD的工作电流随时间变化的信息及所处环境的温度,绘制出LD的老化曲线,即恒功条件下的“I-t曲线”,然后推断LD的使用寿命。     

用于光纤通信的1.55μmDFB激光器的可靠性分析

对用于光纤通信的InP基1．55μm DFB激光器的可靠性进行了研究。测试并分析了100℃时100mA和150mA2种电流应力条件,经过1700h老化,测试分析了激光器特性随时间的变化情况,拟合出在100C,150mA条件下的激光器寿命存1000h小时左右。根据实验结果对比。提出了一种新的利用温度、电流两个加速度变量同时进行加速老化,快速估计激光器寿命并分析其可靠性的方法。对新的寿命估算方法进行了详细的讨论。     

双应力交叉步进加速退化试验下大功率半导体激光器寿命预测方法

高可靠性已成为大功率半导体激光器实用化的重要指标之一，而寿命预测是大功率半导体激光器可靠性评估的首要环节。文中提出了一种双应力交叉步进加速退化的试验方法，对830 nm F-mount封装的大功率半导体激光器进行了四种不同的双应力条件A[22℃，1.4 A],B[42℃，1.4 A],C[42℃，1.8 A],D[62℃，1.8 A]下的电流-温度交叉步进加速退化试验研究，对光输出功率退化轨迹进行拟合，按照80%功率退化作为失效判据，结合修正后的艾琳模型和威布尔分布外推得到器件在正常工作条件下的平均失效时间(MTTF)为5 811 h。文中给出了完整的加速退化模型建立过程与详细的外推寿命计算方法，并对模型进行了准确性检验，误差不超过10%。该方法相比单应力恒定加速试验方法，可以大幅度节约试验时间和试验成本，这对于大功率半导体激光器的自主研制具有重要的指导意义。     

半导体激光器电导数及其可靠性的研究

为了探索和验证半导体激光器电导数参数与其可靠性的关系,将12个半导体激光器串联后进行高温加速电老化,直到器件不激射。监测在加速老化过程中半导体激光器电导数参量的变化情况。通过分析老化期间监测的数据,发现电导数曲线在阈值电流处的下沉高度随着老化时间的增加而变小;结特征参量与电导数曲线(在大于阈值电流的工作状态下)在电流I=0处的截距值随着老化过程逐渐变大。并且结特征参量的变化量在早期处于比较小的平稳状态,然后快速增加到一定值并保持一段时间,之后快速下降并最终稳定在比较小的值,这说明器件退化分为3个阶段:在早期退化较慢,之后退化很快并保持一定的退化速度,最后又到了慢速退化期。从实验结果得知电导数参量与器件的寿命和老化程度有密切关系,并且电导数参数可表征半导体激光器的退化状态。     

回音壁微腔激光器电老化试验及寿命分析

为了考察深刻蚀结构的回音壁模式半导体微腔激光器的寿命,采用恒电流模式对InGaAsP/InP多量子阱耦合双圆微腔激光器进行了电老化试验,电流应力为100mA,老化总时长为1400h。对比了电老化试验前期、中期和后期器件的输出光谱和功率-电压-电流(P-V-I)特性,以器件稳定工作的电老化中期为例分析了器件的性能。分析了输出功率和阈值电流随时间的变化情况,判断出在电老化试验期间器件退化模式始终为渐进模式。以器件输出功率降到初始值的50%作为失效判据标准,在100mA电流下,器件的寿命约为1200h。     

1.06μm大功率连续半导体激光器

利用金属有机化学气相淀积(MOCVD)技术,生长了InGaAs/AlGaAs分别限制压应变双量子阱和单量子阱两种材料结构,通过对不同腔长单管激光器的LIV测试获得内部参数,对单、双阱两种材料结构器件参数进行对比分析,确定了单量子阱结构作为1.06μm大功率半导体激光器的材料结构。通过研究单管激光器的电光转换效率与腔长、注入电流的关系,获得了最高达到57.5%的电光转换效率。对1mm腔长单管激光器进行了大电流高温加速老化测试,结果显示研制出的单管激光器室温下在1.5A工作电流下寿命远大于104h。     

半导体激光器空间辐射应力加速寿命实验模型

通过对半导体激光器在空间环境中辐射损伤机理的分析,得到了器件在辐射条件下的性能退化规律以及辐射过程中的退火规律。在此基础上,建立了辐射应力加速寿命实验模型,获得了故障时间、加速因子、故障概率分布函数、概率密度函数和平均故障前时间的表达式。模拟了三组应力分别为100、50和10Gy/s情况下器件的性能退化数据,进而对加速寿命实验模型的参数进行了估算,求得器件在0.03Gy/s的正常应力条件下的故障时间为43862h。基于威布尔故障分布,利用应力为50Gy/s的加速试验模拟数据,得到了器件的故障概率分布函数以及平均故障前时间,其平均故障前时间约为39755.8h。     

激光二极管寿命测试方法研究

文中介绍了半导体激光二极管(LD) 寿命测试的理论依据,给出了寿命测试的数学模 型,并据此设计了LD 高温加速寿命自动测试系统。系统通过采集恒流工作LD 的平均输出光功率随时间变化的信息,绘制LD 的老化曲线,即恒流条件下的P - t 曲线,或通过采集恒功工作LD 的工作电流随时间变化的信息,即恒功条件下的I - t 曲线,然后推断LD 正常条件下的使用寿命。     

环形腔氦氖激光器加速寿命试验分析

为了找到特定条件下使用环形腔氦氖气体激光器寿命估计理论模型与寿命试验方法,文中假设环形腔氦氖激光器的工作寿命分布规律,在大电流应力下满足威布尔分布,选取电流作为加速应力,对环形腔氦氖激光器进行加速寿命试验。通过最小二乘法对试验数据进行处理,试验结果验证了假设的正确性,得出了环形腔氦氖激光器在正常工作电流下的特征寿命,可以通过大电流应力下的特征寿命来计算,有效缩短了试验时间。     

1.3 µm buried heterojunction laser diodes under high electrical stress: Leakage currents and aging behavior

Investigations on 1.3 μm DCPBH laser diodes under high electrical stress are reported. Leakage currents are identified by electro-and photoluminescence. Experiments on laser diodes with additional collector contacts to the n-InP floating layer show that blocking layer leakage is strongly enhanced by transistor action. The observed aging behavior is described. Excellent stability is observed for our diodes, more so after stress testing. It is found that stress test aging of diodes from moderate quality wafers, which typically still strongly levels off in time, is not caused by an increase in leakage current via the blocking layers, but by an increased leakage in and/or around the mesa. Though transistor action has a strong influence on device performance at high currents, thyristor breakover is shown to be absent in DCPBH-diodes: primarily due to lateral conduction in the blocking layers. Experimentally, thyristor breakover could be obtained by restricting the lateral conduction to about the channel width or less.     

节能灯电容器老练工艺的研究

研究了老练工艺对节能灯电容器漏电流的影响，通过不同条件（温度、电压、时间）下进行老练的试验，表明温度是影响漏电流及其稳定性的最主要因素。指出了保证节能灯长寿命、高可靠工作的三个因素：电容器在高温（１０５℃）下漏电流小；常规测试漏电流稳定；损耗小，阻抗频率特性好。     

Application of Cumulative Degradation Model to Acceleration Life Test

A general degradation model which includes conventional acceleration tests such as fixed, progressive, and step stress experiments is derived from the reaction theory under the assumption of linear degradation accumulation. Its application to the acceleration test is discussed. According to the reaction theory, degradation of the characteristic parameter, ? is connected to reaction rate K and time t by a linear transformation function f(?) = Kt. The total degradation is determined by the linear accumulation of the Kiti product such as f(?n)= # Kiti. This relationship is also expressed as a generalized Miner's equation #(ti/Li) = 1 in which ti and Li are the actual stressing time and expected life under the ith stress condition, respectively, and # ti is the life expectancy of the component under successive stress conditions from i = 1 to n. Validity of this linear accumulation assumption is investigated under various stress application paths. For monotonic step-up, cyclic, and random stress, the rule almost holds as a whole, but monotonic step-down stress sometimes causes erroneous recovering effects of the parameter. The degradation accumulation principle is effectively applicable to integrate degradation and failure pattern information and also to avoid some shortcomings of conventional life test methods. 1) For example, in order to find efficiently the life vs. stress plot, we could combine the degradation (failure fraction) vs. stress diagram, obtained by one step stress experiment, and the knowledge of the degradation pattern obtained by a constant stress test.     

Estimation for a life model of transformer insulation undercombined electrical and thermal stress

A life model for power transformer insulation is proposed. It is the Arrhenius model with a weighting factor for the enhanced reaction under combined thermal/electrical stress. Laboratory tests are used to evaluate the model's parameters. The thermal and thermal/electrical stress aging data on Fish paper are presented and analyzed. The estimates from the life model are close to the experimental results. It is hoped that the life model is extendable to other engineering materials. The model's parameters can be evaluated from two laboratory tests, thermal aging and combined thermal/electrical aging. For the Fish paper, when thermal stress is increased by 30°C, the life is reduced by a factor of 2; at 70°C life was 238 hours and at 100°C life was 120 hours. The material life was further reduced by a factor of nearly 2 when subjected to thermal/electrical stress: at 80°C life was 200 hours, whereas at 80°C and 600 Vac life was 118 hours. Electrical stress is important in accelerating the material degeneration