Why Clean Boards should be a Priority for the SMT Sector Sheila - PowerPoint PPT Presentation

Why Clean Boards should be a Priority for the SMT Sector Sheila Hamilton Teknek Limited

Outline 05/03/2019 EEARS 2011 2

What does Teknek do? • Teknek manufactures high efficiency contact cleaning systems using proprietary technology for removing particles of contamination down to 1 micron from substrates at several stages during the manufacturing process 05/03/2019 EEARS 2011 5

Double Sided Option Pre-Sheeted Adhesive Roll traps contamination Elastomer cleaning rollers Static elimination PCB Feed Panel conveyor

Single Sided Option Pre-Sheeted Adhesive Roll traps contamination Elastomer cleaning rollers Static elimination PCB Feed

Assembly Process Defect Chart According to data from the Surface Mount Technology Association 74% of defects in PCB manufacturing process are related to solder paste. Printing Process Related Defects [ Source: SMTA 2000 ]

Board failures Some typical board failure mechanisms

Contamination related issues found by 3D-SPI Excessive solder paste deposit Desired amount of paste Chip Chip Reason: Volume: 205% (Excessive Error) Dust and dirt from board manufacture and storage cause poor gasketing from stencil to PCBs

Contamination related issues found by 3D-SPD Insufficient solder paste deposit Desired amount of paste Insufficient paste may lead to parts separation or cracking of the fillet during accelerated life testing. Volume: 35% Reasons: Contamination creating blockage of stencil hole, meaning solder paste cannot fill the aperture properly

Contamination related issues found by 3D-SPI CSP or BGA After Reflow CSP or BGA Open Circuit

Contamination related issues found by 3D-SPI Reasons: Foreign substances are on the PCB’s Too many prints without wiping the stencil

Conductive contamination analysis using EDX EDX result = Mg, Al 200µ

Conductive contamination analysis using EDX EDX result = Mg, Al 200µ

Conductive contamination analysis using EDX EDX result = Mg, Al 100µ

Conductive contamination analysis using EDX EDX result = Sn 50µ

Conductive contamination analysis using EDX EDX result = Cu,Ni 50µ

Contamination from boards collected on Adhesive Roll can be analysed

PPM Improvement

Cleaning = yield improvement = ROI Koh Young AOI – overall combined supply results Teknek SMT installed weeks 36 -38 Approx 30% yield improvement

Yield Improvement Teknek SMT machine results: • Overall fails fall from an average of 6.66% to 4.6% - an improvement of 31% • Excessive solder faults fall from 1.53% to 0.6% - an improvement of 61% • Bridging falls from an average of 1.13% to 0.43% - an improvement of 62%

Benefits of Teknek Contact Cleaning  Increase Yields  Improves solder joint integrity  Removal of random and variable contamination related defects  Ensure a clean surface for printing and maximise print quality  Ensures better stencil to board gasketing  Reduces tombstoning / rework / rejects  More reliable product  Reduced field returns  Saves time and money