Mechanical Systems and Signal Processing Volume 241, 1 December 2025, 113428 doi.org/10.1016/j.ymssp.2025.113428

Flip-Chip Microbumps Reliability Study: Enhancing Defect Features of Vibration Signals Using Dual-Drive Adaptive Reweighted Sparse Framework

Yu Sun¹, Lei Su¹, Jiefei Gu¹, Xinwei Zhao¹, Tong Tong¹, Ke Li¹, and Michael Pecht<sup>2

1</sup>Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology, School of Mechanical Engineering, Jiangnan University, Wuxi 214122, China
²Center for Advanced Life Cycle Engineering, University of Maryland, College Park, MD 20742, USA

For more information about this article and related research, please contact Prof. Michael Pecht.

Abstract:

The effective extraction of weak defect features is crucial to the reliability analysis of flip-chip microbumps. A novel dual-drive adaptive reweighted sparse (DDARS) framework is proposed, which can skillfully realize the time-varying noise suppression and unsupervised feature stabilization of flip-chip vibration signals under large-scale environmental disturbances. Specifically, the compact representation (CR) of patch operators Λ and Λ⁻¹ are defined to segment the high-dimensional data into low-scale time-varying noisy patches. By integrating the prior knowledge of noise variance distribution and singular value sparse distribution, an adaptive knowledge prior reweighted matrix(ARM) is constructed to precisely reweight and match sparse regularization terms, thereby effectively mitigating time-varying noise interference. Quadratic sparse projection constraints are introduced under the multi-patch sample condition, utilizing quadratic sparsity to evaluate feature saliency and stabilize the potential representation of signal features. Based on the potential connection between patches and sweep-frequency signals, analyze the sparsity intensity of signals in different time periods to guide the optimal frequency range for ultrasonic excitation of chips. The validity of DDARS is verified through qualitative and quantitative analysis with simulated signals and data from engineering application examples, which can provide technical support for flip-chip microbumps reliability analysis.

This article is available online here, and to CALCE Consortium Members for personal review.