超声检测在IGBT可靠性评估中的应用

摘要

The thermal conduction in the IGBT modules can be affected by the interface defects, resulting in the thermal failure of the modules. It is one of the important factors for the reliability of IGBT modules. Compared with X-ray inspection and sample preparation microscopy technique, the acoustic inspection technology has the advantage of high accuracy, high sensitivity, low cost, high speed and nondestructivity, which can be used to detect the different internal defects such as delamination and void. It is impor-tant for the evaluation of the electronic component reliability. Thus the acoustic inspection technology was applied to the evaluation of IGBT reliability in this paper. The interface defects in the IGBT modules were inspected by applying the layer-by-layer acoustic in-spection technology to analyse the process quality of the interfaces, which was helpful for finding problems in the materials or process of the IGBT modules. It is not only instructive for the process improvement of enterprises, but also significant for the improvement of the IGBT quality.%IGBT模块内部的界面缺陷会影响其热传导,导致模块失效,是影响IGBT模块可靠性的重要因素之一.在常用的缺陷检测方法中,超声检测与制样镜检、X射线检查等技术相比,具有定位准确、 检测灵敏度高、 成本低、 检测速度快、 不损伤样品等优势,能够有效探测样品内部任意部位的各种缺陷(如分层、 空洞等),对元器件的可靠性评估有着重要的意义.本文将超声检测技术应用于IGBT模块的可靠性评估,从IGBT模块的热失效机理出发,通过利用逐层超声检测技术分析模块内部各界面的工艺质量,实现对IGBT模块内部界面缺陷的有效检测,准确找到IGBT模块材料、 工艺中出现的问题,为研制单位的工艺改进提供借鉴,对IGBT模块质量提升具有一定的指导意义.