Hot-Bump-Pull-Application-Note.pdf - 第2页

Hot Bump Pull/Hot Pin Pull Application Note What is Hot Bump Pull? Hot Bump Pull load cartridge e new Nor dson DAGE 4000 Plus HBP system is a totally industry unique solution, conforming to IPC-9708 as well as JEIT A ET…

Although these mechanical test methods test the entire

assembly, it can however be dicult to dierentiate

the types of failure modes occurring during the test.

Common factors which contribute to dierent failure

modes include:

• Solder metallurgy

• PBAmaterials

• Reowconditions

It is therefore important to isolate the failure modes

in order to identify any weaknesses in the assembly.

is is an important part of development and

production, as it ensures correct design of product,

manufacturing process control as well as quality of

product produced.

Hot Bump Pull/Hot Pin Pull

Application Note

e shift from tin-lead to lead-free materials has had

many aects on the surface mount technology

and printed circuit board industries. ese aects

continue to be a major focus of many sectors from

telecommunications, military, aerospace to consumer

electronics.

A common failure mode in lead-free assemblies is pad

cratering, where the contact pad on a PCB or package

substrate lifts away. ere are many factors that cause this

failure mode to be more prevalent in lead-free assemblies

compared to tin-lead assemblies, these include:

• Lead-free solders are mechanically stier than tin-lead

solders, hence it transfers more strain to the assembly.

• Lead-freesolderrequireshigherreowtemperaturesas

well as cooling rates compared to tin-lead. is can

lead to increased strains on the assembly.

Mechanical testing such as bend and shock testing are

common practices on surface mount assemblies and

printed circuit boards in order to verify product design,

ensure quality and ultimately to ensure product longevity.

e mechanical stresses applied, evaluate the susceptibility

of a product to failure.

Hot Bump Pull/Hot Pin Pull Application Note

What is Hot Bump Pull?

Hot Bump Pull load cartridge

e new Nordson DAGE 4000Plus HBP system is a totally

industry unique solution, conforming to IPC-9708 as well

as JEITA ET-7407A. It is fully integrated into a single load

cartridge on a standard 4000Plus system. Heating, cooling

stages and pin clamping mechanism are integrated into the

single load cartridge. e Paragon

™ software provides a user

friendly interface via temperature time proles to setup a test.

e new cartridge design allow simple straight test pins to

be used, allowing maximum force to be transferred as well as

providing a low cost consumable for testing. e new straight

pin design provides successful and consistent testing.

It is important to pull the pin vertically, directly by the

apparatus without imposing any bending moments.

e latest pad cratering standard, IPC-9708, denes hot bump pull as a method to evaluate the susceptibility of

printed board assembly materials and designs to cohesive dielectric failure underneath surface mount technology

attach pads. A method that can be used to rank order and compare dierent materials and parameters.

The Hot Bump Pull Test Procedure

e test procedure consists of two parts, set up of the test parameters and positioning of the pin over a solder bump.

Firstatemperatureproleiscreated,thisallowsausertoinputtemperatureandtimecriteriaforreowandtestconditions.

is simple interface only requires the desired temperature and the time to reach that temperature. e heating and cooling rates

as well as test execution are then automatically handled by the hardware and software.

A temperature time prole consists of the following stages.

Preheat

Soak

Rate of rise

Reﬂow/Liquidus

Cool down

Test execution

Close up of copper probe on BGA

Application Note Hot Bump Pull/Hot Pin Pull

Temperature-time proﬁle in Paragon™

Test results in Paragon™

T1 is the preheat region, this is selected by dening the

temperature to reach and the time to achieve this heating period.

T1 to T2 is the soak period, the soak time can be selected.

T2 to T3 is the rate of rise.

A straight pin is vertically inserted into the cartridge, where it is held in place. e pin is then lowered onto the solder bump via motorised

horizontal and vertical stages. e pin is set so that it is touching the solder bump. e test is then executed, where the pin temperature

rampsupaccordingtothedenedtemperatureprolecreated.Atreowpointthepindropsdowntoadesiredlevel,ensuringagood

solder joint. e clamping mechanism then engages and clamps the pin so it is ready to be pulled. e cooling is handled internally by

pulsing compressed air past the pin and onto the test sample, cooling at the dened temperature prole.

Once the test temperature is reached, the test is automatically executed, recording the force-time,

force-distance and energy values.

T3toT4isthereowperiod,thereow

time period can be selected.

T4 to T5 is the cooling period.

T6 is the temperature where the test will be executed.

Close up of solder ball reﬂow