pH neutral Cleaning Agents – Market Expectation & Field Performance

Conference: PCIM Asia 2019 - International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management
06/26/2019 - 06/28/2019 at Shanghai, China

Proceedings: PCIM Asia 2019

Pages: 8Language: englishTyp: PDF

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Authors:
Tosun, Umut; Patel, Jigar; Nukala, Kalyan; Gazcon, Fernando (ZESTRON Americas, USA)
Ji, Jerry (ZESTRON China, China)

Abstract:
With regard to precision cleaning applications within electronics manufacturing, pH neutral product development was a major breakthrough in recent years. The impetus for this development resulted from changes with regard to solder paste formulations and resulting assembly processes. The greater use of lead-free solder paste and the required higher reflow profiles have resulted in even more difficult to remove burnt-in flux residues. Coupled with increases in component density, larger component packages, higher lead counts, finer lead spacing, and lower standoff distances, effective cleaning is greatly challenged. The aqueous alkaline based cleaning agents can effectively remove these flux residues, however, the process often requires an increase in wash temperature and exposure time, chemical concentration, and mechanical energy. Although an efficient and effective cleaning process can be developed, oftentimes, the required operating parameters present a new set of challenges with regard to material compatibility. Since their introduction, the newly developed pH neutral formulations have proven to be capable not only of removing these difficult post reflow residues from complex board geometries, but do so without affecting material compatibility of sensitive components. Additionally, they perform at low concentration levels. This study reviews the performance of pH neutral cleaning agents as compared to alkaline cleaning agent alternatives and includes field data demonstrating their effectiveness with regard to material compatibility and cleaning performance.