基于小波变换的集成电路内部缺陷检测方法

Internal defect detection method for integrated circuit based on Wavelet transform

随着集成电路向多功能、高精密、高集成度的发展,集成化多层封装技术成为关键,而传统的表面缺陷检测和功能性测试方法对内部缺陷无法实现有效检测.X射线可通过透射成像直观地呈现元器件的内部缺陷,为极大规模集成电路产品的高可靠性生产提供了有效的检测手段.然而,集成电路的X射线图像灰度水平低、对比度低、有效特征细小,难以实现有效的检测.针对该问题文章设计了一种基于小波变换的集成电路内部缺陷检测方法.该方法利用小波的多分辨率分析特点,采用小波同态滤波方法对集成电路的X射线图像进行预处理,提高图像的对比度,进而采用小波模极大值方法提取缺陷的有效边缘供给工业检测判断.实验结果表明,该方法提取的缺陷边缘清晰、数量完整,为保证内部缺陷检测精度、提高集成电路封装质量提供依据.

With the development of multi-function,high precision and high integration density of the integrated circuits(IC),integrated multi-layer packaging technology attracts much attention.Some existing surface defect detection methods and functional tester are infeasible for the internal defects in multi-layer packaging.X-ray detector can penetrate packaged components and yield projective images that contain internal defects,which provides a very effective means to tackle IC internal defect detection and high-reliability production of IC.However,X-ray images of IC exhibit characteristics of low gray level,low contrast and contain very small fine features,resulting in extreme challenges for internal defect detection.In this paper,considering the multi-resolution analysis of wavelet,a Wavelet transform based internal defect detection method for IC is proposed.Firstly,a wavelet homomorphic filtering method is adopted to preprocess IC X-ray images,resulting in improvement of image contrast.Then,wavelet modulus maximum method is chosen to extract the effective edge of internal defects.Experimental results demonstrate that the edge details of internal defects are clear and complete,which provides a basis for precision of internal defect detection and the quality of integrated circuit package.