1. Why we clean; What we clean.
Selecting a Winning Combination for Electronic Assembly

2. Why clean? Performance Cosmetics It Pays to CLEAN
Contractual Reliability
It Pays to CLEAN

3. IPC/EIA J-STD 001/D Requires Clean Boards Class B & C Electronics
8.3.1 No Particulate matter (all classes)
No lint, solder splash, dross, wire clippings
No loose or dislogable solder balls
8.3.2 Unless otherwise specified (all classes), assemblies shall be cleaned and be:
Free from flux residue (1X)
< 1.56 micrograms/cm2 NaCl equivalent ionizables
Appendix B standardizes a testing protocol to be used when implementing new flux materials or validating a cleaning process change
SIR, ROSE, Ion Chromatography

4. Confusion leads to poor choices
Saving a dollar by not cleaning may cost $100’s of repairs or worst, lost customers
Exponential rule of repair
board level = $1
assembly level = $10
customer level = $100

5. Soils to Clean Dust & Dirt Solder balls
Oils Solder Paste Plating salts
Adhesives Finger prints
Fluxes

6. Soldering Fluxes Flux Type Hand solder Wave solder Wire solder SMT
Paste
Notes
Water soluble
-Must be cleaned
About 1/3 of market
Common
Residues usually water soluble
High temperature can change to non-water soluble
Can use chemistry 1-5%
No-clean low residue
-Should be cleaned
Available
Unusual -because of dull solder
Low solids no-cleans require heat to de-activate flux activity as the active agent evaporate only if heated
No-clean
bulk
Unusual because low residue is preferred
High solids no-cleans encapsulate activators in hardened flux matrix
Could be a rosin or resin based flux R
RMA RA
RMA common
Needs cleaning
RMA on old military projects
Mil-F military classifications
R – Rosin non-activated
RMA – Rosin mildly activated
RA – Rosin Fully activated
Lead-free
Any of
the
above
made
For higher temperature

7. Cleaning Agents Catagory Kyzen Petroferm Zestron other
Applications Notes
Aqueous
Water only
Water – tap
Water - DI
Water Soluble Fluxes
Residues usually water soluble
Heat usually required
Sometimes need defoamer
Mixtures
Non-reactive
I3330
Axarel
EC-7R
SP50
Vigon
SC200
SC202
Some LF Fluxes, Most RMA’s
Work by dissolving
may need heat
Non-foaming
neutral pH
Does not affect metals
Less aggressive
Less complicated waste disposal
Reactive
XJN, XJN+, 4625
Hydrex LF
New*
Atron 205, Vigon 200+
ALL Fluxes
Referred to as saponifier
Amines react with flux
High pH -10 to 12
Can attach metals
Needs heat 125 to 200F
More difficult to close loop
Organic
Solvents
Cybersol
MegaSolv
Lenium
DS-100
IPA
Toluene
Water Soluble and RMA
Some Lead-free & no-clean
No water – water free
Closed loop with Mega resins
Combustible or flammable design
Always closed-loop

8. Soil Removal Soil type Key to success Fluxes Process Flexibility
Time, temp, concentration, Automation
Solder balls
High energy, good flux cleaning
Solder paste
High energy, Process Flexibility and Waste management
Dirt & Dust
High energy, Automation
Finger prints
Polar/non-polar solvent
Plating salts
Polar solvent - heated
Machine Oils & lubricants
Organic solvent unless water soluble
Adhesives
Organic solvent, low temperatures

9. AAT Recommended Systems
Soil type
Key to success
AAT cleaner(s)
Reflowed Fluxes
Process selection
Time, temp, concentration, Automation
Inline
AquaTherm
Mega
X-Cleaner
Emulsionator
Solder balls
High energy, good flux cleaning
X-cleaner
Solder paste
High energy, chemistry selection, waste management
Dirt & Dust
High energy
Cyclone
Finger prints
Polar/non-polar solvent
Emuslionator
Plating salts
Polar solvent - heated
Machine Oils & lubricants
Organic solvent unless water soluble
Adhesives
Organic solvent, wash and rinse, high energy, time, temp
Emulusionator

10. Critical Questions to answer in Selecting a Winning Cleaning Process
What are we cleaning?
What standard(s) apply?
What solvent are we using?
What equipment is selected?
How are we going to qualify
and control the process?