Research on Defects Inspection of Solder Balls Based on Eddy Current Pulsed Thermography

Abstract

In order to solve tiny defect detection for solder balls in high-density flip-chip, this paper proposed feasibility study on the effect of detectability as well as classification based on eddy current pulsed thermography (ECPT). Specifically, numerical analysis of 3D finite element inductive heat model is generated to investigate disturbance on the temperature field for different kind of defects such as cracks, voids, etc. The temperature variation between defective and non-defective solder balls is monitored for defects identification and classification. Finally, experimental study is carried on the diameter 1mm tiny solder balls by using ECPT and verify the efficacy of the technique.

Eddy Current Pulsed Thermography with Different Excitation Configurations for Metallic Material and Defect Characterization

“…Simulation and experimental results demonstrate different ECPT configurations own individual strengths for different shape samples and defects detection applications. One proposed configurations of ECPT with Helmholtz coil with relatively uniform inductive heating can be applied for crack edge [ 4 , 24 ] detection, and other proposed ferrite-yoke-based excitation can be applied for the characterization of RCF cracks in the rail track heads [ 14 , 15 ] with uniform heating and open-view thermal imaging. The open-view field imaging can be applied for large area inspection in contrast to the ECPT with the line-coil.…”

An Overview of Non-Destructive Testing Methods for Integrated Circuit Packaging Inspection

“…The reflected wave oscillates at the same frequency as the thermal wave [ 106 ]. The active thermography methods have been adopted extensively to inspect the IC packaging (pulsed [ 94 , 95 , 107 , 108 ] and lock-in [ 92 , 93 , 101 , 109 ]). A sample setup (both schematic and actual) of the active thermography is shown in Figure 13 .…”

Quantitative Detection of Cracks in Steel Using Eddy Current Pulsed Thermography

“…The quality, internal state, structure, and defects of the examined objects are determined based on the temperature field distribution. From the light and dark areas in the thermal image, the location of defects can be determined [ 13 ]. Compared with conventional nondestructive testing methods, this approach offers many advantages as it is a non-contact measurement technique with high sensitivity, fast response, and a large detection area that provides intuition and high precision [ 14 ].…”