x-ray inspection of bgas

X-Ray Inspection of BGAs

November 2017

Your BEST choice in PCB Test/ Rework/Repair and Solder Training & Tools www.solder.net

X-Ray Inspection-BGAs IPC-A-610 G Criteria

You DO NOT HAVE to x-ray BGAs according to the IPC-A-610G

CHOICEA.Develop process. Validate process using x-ray. Sample plan inspection. Need to have objective

evidenceOR

B. Inspect via x-ray

Note: X-ray equipment not intended for electronic assemblies or not properly set up can damage sensitive assemblies


Collapsing Soldering Balls

Note 1. Design induced voids, e.g., microvia in land, are excluded from this criteria. In such cases acceptance criteria shall be established between the manufacturer and user.

Note 2. Manufacturers may use test or analysis to develop alternate acceptance criteria for voiding that consider the end-use environment.

Feature Classes 1,2,3 X-Ray

Alignment Solder ball offset does not violate minimum electrical clearance.

Can scan to see separation of balls or use built-in metrology tools

Solder Ball Spacing

Solder ball offset does not violate minimum electrical clearance.


Soldered Connections

No solder bridging; BGA solder balls contact and wet to the land forming a continuous elliptical round or pillar connection.

No non-common connections of solder balls. Telltale sign is same ball volume/area based on min amd max set oints

Voids 30% or less voiding of any ball in the x-ray image area.1,2

Modern x-ray can measure


Non-Collapsing Soldering Balls

Note 1. Design induced voids, e.g., microvia in land, are excluded from this criteria. In such cases acceptance criteria shall be established between the manufacturer and user.

Note 2. Manufacturers may use test or analysis to develop alternate acceptance criteria for voiding that consider the end-use environment.

Feature Classes 1,2,3 X-Ray

Alignment Solder ball offset does not violate minimum electrical clearance.


Soldered Connections

No solder bridging; BGA solder balls contact and wet to the land forming a continuous elliptical round or pillar connection.

No non-common connections of solder balls. Telltale sign is same ball volume/area based on min and max set points

Voids No to little voiding


IPC-7095 Inspection Guidelines

NOTE: These are guidelines (suggestions)


Oblique View


Know What You Are Looking For


Open


Short


Broken Wire Bond


Voiding


Starved Solder Joint


Non Uniform Collapse


Solder Anomolies


Uneven HeatingSmaller

Larger


Measurement and QC


iPhone 4 Example

[email protected]

X-Ray Inspection of BGAs

x-ray inspection of bgas

Engineering