|
HASL - Hot Air Solder Leveled |
Lead free - RoHS Compliant |
No |
|
Hot Air Solder Leveling (HASL), is a process where solder
masked, bare copper PWBs are cleaned, fluxed and then submerged into a tank
of molten solder. Upon extraction from the solder tank, air knives blow
excess solder from the holes and off the surface of the PWB. Nationwide
Circuits uses Alco-met electrolytic grade 63% Tin / 37% Lead solder in its
solder pot, insuring reliable and contaminant free solder joints.
www.alcomet.com
|
Maximum Shelf Life |
12 months |
|
Multiple Assembly Cycles |
Yes |
|
Thermal Shock |
Yes |
|
Fabrication Costs |
Low |
|
Solder Joint Integrity |
Excellent |
|
Wettable |
Excellent |
|
Flatness |
Poor |
|
Wire Bondable |
No |
| |
|
ENIG - Electrodless Nickel Immersion Gold |
Lead free - RoHS Compliant |
Yes |
| The
Electroless Nickel - Immersion Gold (ENIG) process is a series of steps that
clean and prepare a PWB to plate in an a auto-catalytic nickel bath,
producing an intermediate layer of 120-200 µ in. This is followed by the
immersion plating of a thin layer of gold, 2-4 µ in thick. The ENIG deposit
meets the RoHS standard and offers a solderable coplanar surface with a long
shelf life. Nationwide Circuits offers Electrochemicals OMG chemicals in its
ENIG Line.
www.electrochemicals.com/ecframe.html
|
Maximum Shelf Life |
12 months |
|
Multiple Assembly Cycles |
Yes |
|
Thermal Shock |
No |
|
Fabrication Costs |
Medium |
|
Solder Joint Integrity |
Good |
|
Wettable |
Good |
|
Flatness |
Excellent |
|
Wire Bondable |
Yes |
| |
|
Immersion Tin |
Lead free - RoHS Compliant |
Yes |
| The
Immersion Tin process deposits approximately a 1 micron layer of dense pure
Tin on the copper surfaces of the PWB. Nationwide Circuits offers the
Technic Leveltech Immersion Tin from Technic Corp.
www.technic.com/pwb/finaltin.htm
|
Maximum Shelf Life |
3-6 months |
|
Multiple Assembly Cycles |
Limited |
|
Thermal Shock |
No |
|
Fabrication Costs |
Low |
|
Solder Joint Integrity |
Good |
|
Wettable |
Good |
|
Flatness |
Excellent |
|
Wire Bondable |
No |
| |
|
Lead Free HASL - Hot Air Solder Leveled |
Lead free - RoHS Compliant |
Yes |
|
Lead free Hot Air Solder Leveling is preformed much like standard Tin/Lead
HASL except the solder pot contains a lead free alloy of solder. The current
make up of the no lead solder alloy offered at Nationwide is
99.25% Tin, 0.7 % copper, 0.05% nickel. |
Maximum Shelf Life |
12 months |
|
Multiple Assembly Cycles |
Yes |
|
Thermal Shock |
Yes |
|
Fabrication Costs |
Medium |
|
Solder Joint Integrity |
Good |
|
Wettable |
Good |
|
Flatness |
Poor |
|
Wire Bondable |
No |
| |
|
Electroplated Gold |
Lead free - RoHS Compliant |
Yes |
|
Electroplated gold PWB's are first electroplated with a nonporous nickel
layer directly over the copper circuitry. The thickness of the nickel layer
is generally between 100-200 µ in. The gold layer is then electroplated over
the nickel in thickness ranging from 10-100 µ in depending upon the
application. Nationwide offers both a cobalt hardened gold for fingers and
contacts and a non-hardened or soft gold for use in wire bonding
applications.
|
Maximum Shelf Life |
12 months |
|
Multiple Assembly Cycles |
Yes |
|
Thermal Shock |
No |
|
Fabrication Costs |
Medium |
|
Solder Joint Integrity |
Poor |
|
Wettable |
Good |
|
Flatness |
Good |
|
Wire Bondable |
Yes |
|
|
Immersion Silver |
Lead free - RoHS Compliant |
Yes |
|
Immersion Silver is processed in a similar manner to ENIG. Like ENIG,
Immersion Silver (Ag) offers a coplanar surface that is readily solderable.
|
Maximum Shelf Life |
9-12 months |
|
Multiple Assembly Cycles |
Yes |
|
Thermal Shock |
No |
|
Fabrication Costs |
Medium |
|
Solder Joint Integrity |
Excellent |
|
Wettable |
Good |
|
Flatness |
Excellent |
|
Wire Bondable |
|
