S.A. Protsenko1, A.V. Turetsky2, Yu.A. Pirogova3, I.V. Goncharenko4

1-4 FSBEI of HE “Voronezh State Technical University” (Voronezh, Russia)

1 sergo2023@bk.ru; 2 tav7@mail.ru; 3 pirogov.alx@gmail.com, 4clashofclans22885@gmail.com

Formulation of the problem. When mounting electronic components on a board during the soldering process, voids inevitably form inside the connection. There are especially many of them in solder joints that have a large area. These voids impair thermal conductivity and generally reduce both the mechanical and electrical reliability of the contact. Therefore, finding ways to reduce the impact of this defect is a fairly urgent task.

Target. Consider the effect of solder mask roughness on the distribution of flux around the contact pad, and also identify the dependence of the formation of voids on the configuration and thickness of solder paste application.

Results. More active fluxes have been shown to produce fewer voids in terms of average total area covering the pad. Analysis of samples prepared using modified stencils showed a significantly lower proportion of voids than when using a standard stencil. In addition, it has been shown that the choice of solder mask type has a significant impact on the formation of voids in solder joints. The best results were achieved using a thin stencil with a larger aperture when the printed circuit boards were without a solder mask, and the surface has the greatest roughness. However, when modified, thicker, smaller aperture stencils were used, the solder mask had no effect on void formation. Thus, it was found that stencil modification can be recognized as a more preferable and effective way to minimize voids in solder joints.

Practical significance. The results obtained can be used to improve the reliability of radio-electronic equipment by selecting optimal soldering technology parameters that affect the reduction of the number of voids in solder joints of components on the board.

Protsenko S.A., Turetsky A.V., Pirogova Yu.A., Goncharenko I.V. Method for minimizing voids in solder joints on a printed circuit board. Radiotekhnika. 2024. V. 88. № 7. P. 31−35. DOI: https://doi.org/10.18127/j00338486-202407-06 (In Russian)

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