ME4 Industrial Application Talk

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ME4 Industrial Application Talk
by Yam Hong See (Seagate Technology)
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Scope

• The QA Engineer In Industry
• The Latest Buzzword Six Sigma
• Case Study on Crystal ESR Characterization

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The QA Engineer In Industry
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Typical Manufacturing Structure
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ME4271 Quality Assurance
Course Syllabus

• Control Charts
• Process Capability Analysis
• Acceptance Sampling
• Reliability Data Analysis

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CareerKnowledge Matrix
A sound knowledge of engineering statistics is
essential.
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What Is Quality?

• The totality of features and characteristics of a
  product or service that bear on its ability to
  satisfy given needs. (ASQC)
• Uniformity about target. (Edwards Deming)
• Fitness for use. (Joseph Juran)
• The loss imparted to the society from the time a
  product is shipped. (Genichi Taguchi)
• The inverse of variability. (Douglas Montgomery)

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Demings Chain Reaction
W Edwards Deming
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Breakthrough Improvement Strategy

• Define the Problem
• Prove the Need
• Form the Team
• Diagnostic Journey
• Remedial Journey
• Maintain the Gain

Joseph M Juran
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The Latest Buzzword - Six Sigma
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(No Transcript)
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What Is Six Sigma?

• A business strategy
• A philosophy
• A statistical measurement

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Cost Of Poor Quality
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Challenging Status Quo

• To deal with a world of declining product prices
• To compete successfully with the best companies
  in the world
• To establish standard language and approaches
  across functions and across businesses
• To develop the next generation of leaders

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What Is Six Sigma?

• A business strategy
• A philosophy
• A statistical measurement

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99 Good is Not Good Enough

• 5,000 incorrect surgical procedures each week
• 20,000 lost articles of mail each hour
• No electricity for 7 hours each month
• Unsafe drinking water for 15 minutes each day

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Breakthrough Improvement
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The Hidden Factory
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What Is Six Sigma?

• A business strategy
• A philosophy
• A statistical measurement

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Six Sigma Metrics

• Conventional Quality Metric Six Sigma Metric
• Defective Parts Per Million Defects Per Million
  Opportunities
• Yield First Time Yield
• Rolled Throughput Yield
• Normalized Yield
• Baseline
• Entitlement
• Goal

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Six Sigma Breakthrough Strategy
DEFINE
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Define

• Problem Description
• Defect
• Baseline, Entitlement Goal
• Project Assessment
• Time Line
• Cost
• Savings
• Initial Project Validation

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Measure

• Key Process Output Variables (KPOVs)
• Identification
• Process Capability Analysis
• Measurement System Analysis
• Key Process Input Variables (KPIVs)
• Identification
• Adequacy of Existing Controls
• Short-Listing

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Analyze

• KPIVs Demographics Matrix
• Verify Significance of KPIVs
• Hypothesis Testing
• Parametric Statistics
• Non-Parametric Statistics
• Multi-Vari Analysis
• ANOVA ANACOVA
• Correlation Regression
• DOE Planning Sheet

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Improve

• Design Of Experiments (DOE)
• Identify Best Process Window
• Revise Process Settings
• Identify Actions Required For Improvement

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Control

• Implementation of Solutions
• Monitor KPOVs
• Control KPIVs
• Closure of Project
• Produce Final Report

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The Six Sigma Black Belt

• Black Belts lead improvement efforts on projects
• The Black Belt ensures that each project follows
  the process of
• Measure ? Analyze ? Improve ? Control
• Dedicated resource of highly skilled focused
  individuals
• Typically 1 of the companys resources
• Among the best people on the site
• A Black Belt performs 5-6 projects per year, over
  2 year assignment (minimum)
• Annual savings of 875K per Black Belt

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The Master Black Belt

• The Six Sigma expert on-site
• Trains and coaches Black Belts, Green Belts and
  others
• Works with Champions to establish priorities and
  goals
• Direct projects in key process areas to success
• Review progress of key initiatives
• Communicate progress of key initiatives
• Eliminate road blocks to ensure achievement
• Drive business focus dedication to improve

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Crystal ESR Characterization
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Background Information

• Failure Crystal unable to initiate oscillation
• Defect Rate 3,500 dppm (Functional Test)
• Root Cause Contamination on crystal blank

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Cost Of Poor Quality (COPQ)

• Scrap of defective crystals Material Cost
• Rework of defective PCBAs Labour Cost
• VMI of reworked PCBAs Labour Cost
• Retest of reworked PCBAs Labour Cost
• Escape of defective PCBAs Customer Good-Will

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Suppliers Counter-Measure

• Electrical Testing of Crystals

R
C
L
C0
Measurements of R, L, C and C0 are made and
compared vs specification limits.
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Suppliers Counter-Measure

• Implementation of Sweep Test

• Consequences of Counter-Measure
• Investment by supplier
• About 1 additional reject
• Failure at Seagate ? 3,000 dppm

?R
Unit is rejectable if ?R?5?
Cost gt Benefit
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Internal Failure Analysis

• Bode Plot of Crystal

Good Unit
? Good gt ? Reject
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Quadratic Transfer Functions

• a) Mechanical System

b) Electrical System
Strategy Review Upper Specification Limit of R
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Characterization of ESR (R)

• Data collected over
• 10 production lots
• 100 units per lot

Current Specifications 40 ohms (max)
Distribution of ESR well within specifications
Data from the 10 lots were pooled.
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Distribution of ESR
Mean 8.1952 Std Dev 1.7306 Skewness 1.4370 K
urtosis 1.8237
Transformation of data set is required
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Box-Cox Power Transformation
Y X² was used to transform ESR
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Distribution of ESR2
Transformation of data set was successful
Mean 0.0165 Std Dev 0.0054
Skewness 0.1361 Kurtosis 0.5709
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Determination of Specification Limits

• Note LSL for ESR2 ? USL for ESR
• a) ? 0.005, LSL for ESR2 0.00260 USL for
  ESR 19.6 ?
• b) ? 0.010, LSL for ESR2 0.00395 USL for
  ESR 15.9 ?

Functional Failure Rate ? 3,500 dppm
USL of 20? was elected (? lt 0.005)
Functional Failure Rate ? sub-100 dppm (over 97
reduction)
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Lessons Learned

• More expensive method ? Best method

• Do not neglect first principles
• Integration of statistics with engineering
  knowledge.

The problems of today cannot be solved with the
solutions of yesterday. Albert Einstein