Implementing Robust Bead Probe Test Processes
Via-In Pad Plated Over (VIPPO) Design Considerations
Screening of Lower Melting Point Pb-Free Alloys
Condensation Testing - A New Approach
Case Study for Improving the PCB Print Process Using Factory Data
DFX on High Density Assemblies
Improved SMT and BLR of 0.35 mm Pitch Wafer Level Packages
Wetting and Solidification of Pure Tin on Polycrystalline Intermetallic Substrates
Latest Industry News
MacBook, iPad Production Delayed as Supply Crunch Hits Apple
Microsoft unveils liquid cooling solution for datacenters
A Theory of (Almost) Everything
Toyota unveils new models in advanced driver-assist technology push
Tech Giants Enter Their Chips in the Race for Self-driving Cars
What will self-driving trucks mean for truck drivers?
4 Great Things That Happened When We Went Remote
iPhone 13 is going to be worth the wait: All the major upgrades we're looking forward to

Improved Reliability of Jet Dispensable Polymeric Coating Material

Improved Reliability of Jet Dispensable Polymeric Coating Material
The study compares a paste that barely passes SIR at 85C/85RH with polymeric material, Silicone conformal, and acrylic conformal coating.
Materials Tech


Authored By:

Hemal Bhavsar1, Dan Duffy, Bruno Tolla, Ph.D.
Kester, An ITW Company
Itasca, IL, USA


OSCA materials are dispensable or printable polymeric coating material, which is One Step Chip Attach Coating material designed to form a protective layer around solder joints, which ultimately results into results into reduced corrosion, salt formation, and dendrite growth. Advantages to using this material includes no masking that reduces process time and cost. The material is designed to have controlled flow after dispense, fast cure and simpler process compared to standard conformal coating. It can be dispensed using Jet or Auger technologies, which integrates into existing assembly equipment. There is no need to coat entire device. Device can be selectively coated on most critical areas or areas known to be susceptible to corrosion. After dispensing, this material can be cured in convection oven and can be cured in few minutes between 140-160oC. This paper presents reliability study of highly corrosive printed paste with polymeric coating material and comparing it with conformal coating.

The study was designed to compare a paste that barely passes SIR at 85C/85RH with polymeric coating material, Silicone conformal coating, and acrylic conformal coating. Another part of this study was to study thickness effect on reliability results. Preliminary results show formation of tin salts around traces and some corrosion on uncoated areas, but it was not observed after polymeric coating material was printed on the board. Using this new material as coating prevents formation of salts, corrosion and dendrite growth. Material thickness and volume of material dispensed on the area is very important to obtain optimum results with this polymeric coating material.


OSCA-C materials are designed to be dispensable specific coating material. Advantages to using this material includes faster processing times, fast curing, and no drying step. There is no masking required and minimal volume of material will be required, which end up reducing cost and much faster processing. This study shows that reliability performance can improved using this material. Paste A performed poorly with dendrites and salt formation, but with OSCA-C material it wasn't observed. Using acrylic or silicone conformal coating showed negligible resistivity improvements.

Initially Published in the SMTA Proceedings


No comments have been submitted to date.

Submit A Comment

Comments are reviewed prior to posting. You must include your full name to have your comments posted. We will not post your email address.

Your Name

Your Company
Your E-mail

Your Country
Your Comments

Board Talk
Solder Paste Volume for BGA Rework
Reflow For Rigid Flex
Delay Before Cleaning Partial Assemblies
Problems With Starved "J" Lead Joints
Solder Paste Transfer Efficiency - What/Why
Can a CTE Mismatch Cause Reliability Problems?
Going Beyond Your Solder Paste Work Life
Issues Mixing Silicone and Acrylic Conformal Coatings
Ask the Experts
Bottom Terminated Components and Vias
Is Solder Mask Considered an Insulator
Reduce Glare During Assembly
BGA BAll Sheer Testing
Components Jumping Around During Reflow
Floor Life of MSD Parts
QFN Open Solder Joints
Delamination Causing Scrap