Immersion Silver

Pros

Cons

Good Wettability

Poor Shelf-Life:                                                  *Must be vacuumed packed for shipping          *Must be vacuumed packed for storage             *Must not handle Surface Areas

Good Coplanarity

Good Reflow Cycles

Good Process times

Low Cost

Fair Process Window

Good Process Control

Poor Adhesion                                                

Good Electrical Testability

Difficult to Re-Work

Organic Solderability Preservative - OSP

Pros

Cons

Good Coplanarity

Poor Shelf-Life:                                          *Degrades with High Temperature                    *Must not handle Surface Areas

Good Surface Oxidation

Re-Workable

Very Low Cost

Reflow Cycles

Good Process Window

Flux Sensitivity

Good Process Control

Poor Wettability

Very Poor Electrical Testability

Poor Adhesion

Electroless Nickel Immersion Gold - ENIG

Pros

Cons

Good Wettability

High Cost

Good Coplanarity

Complex Process

Good Reflow Cycles

Not Re-Workable

Good Surface Oxidation

Ni/Sn brittle Solder Joints

Good Shelf-Life

Field Failure

Good Adhesion

Fair Process Window

Wire Bonding    

Fair Process Control

Keypads

Good Electrical Testability

Hard Gold

Pros

Cons

Good Wettability

High Cost

Good Coplanarity

Not Re-Workable

Good Reflow Cycles

Good Surface Oxidation

Good Shelf-Life

Good Process Window

Good Process Control

Good Adhesion

Good Electrical Testability

White Tin

Pros

Cons

Good Wettability

Long Process Time

Good Coplanarity

Fair Process Window

Good Reflow Cycles

Possible Tin Whiskers

Good Surface Oxidation

Problems if Tin Thickness is Low

Low Cost

Good Process Control

Good Adhesion

Good Electrical Testability

Lead-Free Hot Air Solder Leveling

Pros

Cons

Excellent Wettability

Process Control

Much Improved Coplanarity over Sn/Pb

Heat Cycle

Excellent Reflow Cycles

Excellent Surface Oxidation

Very Low Cost

Re-Workable

Good Process Window

Good Adhesion

Excellent Solder Joints

Excellent Shelf-Life

Good Electrical Testability