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Statistical Process Control
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Statistical Process Control
Manufacturing process quality assurance.
Solder joint measurement data,collected during x-ray
test, can be statistically analyzed to identify
manufacturing drifts,trends and other relevant process
quality issues.
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Statistical Process Control Chart
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Is your process in control & capable?
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Statistical Analysis of Manufacturing Process
X-Ray Images Statistical Data
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Statistical Data from BGA Inspection
Void [%]Frequencyofoccurrence
20%
Histogram
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Statistical Data from BGA Inspection
Void [%]Frequencyofoccurrence
10%
Histogram
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Statistical Data from BGA Inspection
Void [%]Frequencyofoccurrence
20%
Histogram
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Statistical Data from BGA Inspection
Void [%]
Frequencyofoccurrence
Histogram
Void [%]
Frequencyofoccurrence
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Statistical Data from other X-Ray Inspections
OPENS SHORTS VOIDS
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Statistical Parameters of Interest
Mean, Average, Expected Value (µ):
central value of a discrete set of numbers:
specifically, the sum of the values divided by
the number of values.
Variance (σ2):
measures how far a set of numbers is spread
out.
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Parameters of Interest: Mean and VarianceFrequencyofoccurrence
µ
σ2
Mean (µ): Average of process performance
Variance (σ2): How consistent process
performance is
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How can we use statistical analysis to manage my
manufacturing process?
Example 1: QFN Opens and Shorts
DAY 1 DAY 3 DAY 5
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Another Example: LED voiding, day 1
8AM 1PM 8PM
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Another Example: LED voiding, day 2
8AM 1PM 8PM
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You can’t manage what you don’t measure
Metrics are critical to manage a manufacturing process
Depending on the process, metrics can be pad voiding,
underfill voiding, shorts, opens, or all of these
Need to collect data and analyze it over time to
properly manage process
Spot checks are inadequate to verify longer term
deviations
Mean and variance of key statistical parameters can
tell you a lot about the performance of your business
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Key takeaways
X-ray inspection systems are safe and easy
instruments to use everyday
Must be closely integrated to all aspects of
manufacturing
Process design
Process validation
Process quality control
X-ray in the loop assures superior quality design
and control
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For more information
Contact us:
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Chat with us live at our website
Email us at info@creativeelectron.com
Call us at 760.752.1192
Learn more at X-Ray University
http://creativeelectron.com/x-ray-university/
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Thanks for your time!

Statistical Process Control for SMT Electronic Manufacturing