Toward reducing no-clean flux spatter during reflow soldering: Investigating the effect of flux type, solder mask, and solder pad design

Veselý, Petr; Dušek, Karel; Froš, Denis

doi:10.1016/j.jmapro.2022.07.027

Cited by 6 publications

(2 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The substrate without the solder mask exhibited the highest surface roughness from evaluated variants of PCB. As the previous state [21,25], the higher surface roughness generally increases the wettability of the liquid. The flux spreading area was thus larger (Fig.…”

Section: Influence Of Different Types Of Solder Maskmentioning

confidence: 83%

Analysis of solder mask roughness and stencil shape influence on void formation in solder joints

2023

View full text Add to dashboard Cite

Voids inside solder joints are empty spaces negatively affecting the mechanical, thermal, and electrical properties of the solder joint. This article deals with this problematics using two novel approaches to reduce voids’ occurrence. The first approach is the change of the roughness of the solder mask to influence the flux spreading around the solder pad. The second approach is the deposition of the same volume of the solder paste to the solder pads using a modified, thicker stencil with smaller apertures. The experiments were performed for solder pastes containing SAC305 alloy and two types of fluxes (ROL0/ROL1). Solder joints were inspected by X-ray imaging, and the shots were subsequently processed by image analysis. For determination of the spreading area of the flux around the solder pad during the reflow process, the tested boards were scanned by a confocal digital microscope. The results showed that more aggressive flux caused less voiding in terms of the average area of voids covering the soldering pad. Analysis of samples prepared with modified stencils showed a much lower proportion of voids than with the standard stencil. Furthermore, the results revealed that the selection of the solder mask type significantly influenced the voids’ formation within solder joints in the case of the unmodified stencil for solder paste deposition. On the other hand, when the modified stencils were used for sample preparation, the solder mask had no further impact on voiding. Therefore, modifying the stencil can be pointed out as a preferable and effective way.

show abstract

Section: Influence Of Different Types Of Solder Maskmentioning

confidence: 83%

Analysis of solder mask roughness and stencil shape influence on void formation in solder joints

2023

View full text Add to dashboard Cite

show abstract

“…During the traditional soldering process, organic flux is applied to metal surfaces to remove dirt and oxide, enhancing the soldering reliability. However, if the flux residues existed in the solder joint, it can cause severe corrosion and the weakening of the soldering strength [ 7 , 8 , 9 , 10 ]. With the miniaturization of solder joints in three-dimensional integrated circuits, it has become more challenging to eliminate the flux, and its impact on the interconnection is becoming increasingly significant [ 11 , 12 ].…”

Section: Introductionmentioning

confidence: 99%

Improvement of Solder Joint Shear Strength under Formic Acid Atmosphere at A Low Temperature

He,

Jiang,

Shen

et al. 2024

Materials

View full text Add to dashboard Cite

With the continuous reduction of chip size, fluxless soldering has brought attention to high-density, three-dimensional packaging. Although fluxless soldering technology with formic acid (FA) atmosphere has been presented, few studies have examined the effect of the Pt catalytic, preheating time, and soldering pad on FA soldering for the Sn-58Bi solder. The results have shown that the Pt catalytic can promote oxidation–reduction and the formation of a large pore in the Sn-58Bi/Cu solder joint, which causes a decrease in shear strength. ENIG (electroless nickel immersion gold) improves soldering strength. The shear strength of Sn-58Bi/ENIG increases under the Pt catalytic FA atmosphere process due to the isolation of the Au layer on ENIG. The Au layer protects metal from corrosion and provides a good contact surface for the Sn-58Bi solder. The shear strength of the Sn-58Bi/ENIG joints under a Pt catalytic atmosphere improved by 44.7% compared to using a Cu pad. These findings reveal the improvement of the shear strength of solder joints bonded at low temperatures under the FA atmosphere.

show abstract

Behavior of Sn-3.0Ag-0.5Cu solder/Cu fluxless soldering via Sn steaming under formic acid atmosphere

Shen

Xiong

et al. 2022

Journal of Materials Research and Technology

View full text Add to dashboard Cite

Toward reducing no-clean flux spatter during reflow soldering: Investigating the effect of flux type, solder mask, and solder pad design

Cited by 6 publications

References 21 publications

Analysis of solder mask roughness and stencil shape influence on void formation in solder joints

Analysis of solder mask roughness and stencil shape influence on void formation in solder joints

Improvement of Solder Joint Shear Strength under Formic Acid Atmosphere at A Low Temperature

Behavior of Sn-3.0Ag-0.5Cu solder/Cu fluxless soldering via Sn steaming under formic acid atmosphere

Contact Info

Product

Resources

About