电子散斑干涉载频调制形貌测量技术

提出了电子散斑干涉(ESPI)载频调制测量物体形貌的方法.在ESPI中,物体表面的微小偏转可引入包含物体高度信息的载波干涉条纹,具有灵敏度高的优点.用摄像机采集该载波条纹图,利用傅里叶变换法可解调出物体高度的位相信息,从而实现物体的形貌测量.     

Nondestructive Measurement of Fatigue Damage of Thermally Sprayed Al2O3/NiCr Using ESPI Method Under High Temperature

High-temperature fatigue (R = 0) damage and deformation behaviors of SUS304 steel thermally sprayed with an Al₂O₃/NiCr coating were investigated using a servopulse fatigue-testing machine, SEM, and an electronic speckle pattern interferometry (ESPI) method. The relation between crack/delamination and strain variation is discussed. Surface cracks occurred at the outer Al₂O₃ coating but stopped at the inner NiCr coating after one fatigue cycle when the tensile stress was 202 MPa at 873 K. They propagated into the NiCr coating but stopped at the substrate, and local delamination occurred along the NiCr/substrate interface after 1 × 10⁵ cycles test in condition (_max = 202 MPa, T = 873 K). Cracks and delamination largely decreased when _max = 115 MPa or T = 573 K. No influence of cycle frequencies (6.7 or 14 Hz) was detected. The strain value measured by ESPI method was confirmed to be almost the same as that obtained with strain gauges at 293 K. Strain values along cracks measured with the ESPI method were much larger than other areas as a result of crack opening under the tensile load, referred to as the strain concentration zone in this work. Positions of strain concentration zones on strain distribution figures by the ESPI method corresponded well to positions of cracks on sprayed coatings. Moreover, strain values largely decreased where local delamination occurred.     

基于电子散斑干涉技术的IC芯片加速寿命预测研究

提出了基于电子散斑干涉技术(ESPI)可预估局部温度最高区域的加速寿命预测方法.实验通过对芯片样品进行了动态工作模式下的功耗评估,预估了芯片局部温度最高的热源区域,尔后对此区域进行去封装处理;在芯片去封装区域,分别测出常温和高温环境下芯片动态上作模式的裸片表面温度,以此数据作为Arrhenius模型中加速因子的结温,求出加速因子;最后,根据实验得出芯片存高温环境下的寿命时间,即可推出其在正常工作条件下的寿命.结果表明,这种方法具有准确、快速和简单的特点,可广泛应用于微电子器件的正常工作寿命预测.