Ccga failure analysis by cutting columns in horizontal cross-section

Abstract

A printed circuit board assembly (PCBA) was failed, and two pins routed from CCGA had no signal output in the electrical performance test at low temperature (C). Visual inspection, X-ray and 3D X-ray examinations did not find any failure in PCBA’s via/wire, solder joint, and CCGA body. In order to find the failure mode of the PCBA, more failure analysis is required. The commonly used vertical cross-section of PCBA will destroy the CCGA. This paper uses the method of cutting the CCGA columns in horizontal cross-section. After the cutting, microscopic inspection of the solder joints on both sides with the CCGA columns revealed no failure. The metallographic section of the solder joint on the side of the printed circuit board confirmed no failure. After the CCGA removed the columns, it is then re-balled and soldered to a new printed circuit board. The electrical performance test confirms that the fault is inside the CCGA. In this paper, the improvement of PCBA failure analysis solved the problem that CCGA will be damaged when cutting samples. The CCGA can be tested and chip-level failure physical analysis can be performed after the board-level failure analysis.