DOE2-INTRO

Introduction to DOE & Application of ECHIP
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Practices of DOE
DOE builds on basic quality tools
Depends on an in-control process
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Control charts Histograms Flow Charts
What are the interactions that would effect the process? Example of Bonding Force and Bonding Time on Ball Shear.
Ball Shear Strength (g)
60 50 40 30 20 10 0
Identify DOE resource needs
A method to help determine time and material resource needs
Knowledge and expertise
Statisticians (if any) can be of help Experts involved in, or related to, the process being tested
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60 50 40 30 20 10 0
0 20 40
Bon time = 30 ms
Bond Time = 10 ms
60 80
Bonding Power
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Interactions Plot
Identification of factors
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Cause and Effect diagrams Pareto charts and Check sheets
Monitoring of changes made by DOE
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Control Charts Scatter plots
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Introduction to DOE & Application of ECHIP
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Ball Shear Test Pareto Chart
Effects of Bonding Parameters on Ball Shear Strength
40 35 30 25 20 15 10 5 0 Bond Power % Effect on Ball Shear
0 20 40 60 80
Bon time = 10 ms
Bond Time = 30 ms
Bonding Force
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Interactions plot - 3-way example
What are the interactions that would effect the process? Example of all three factors.
Section 2
Design Of Experiment - An Introduction
Feb. 2000
Introduction to DOE & Application of ECHIP Sec#2 Page 1
Purposes and practices of Design of Experiments A Method to:
describe – predict – and control variables in a process in order to understand and improve the process or product.
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In order to improve a process or system one must first understand it. If it is not understood, then any change made to it is tampering. The effect then is almost always detrimental to the quality of the process and product.
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More difficult to measure savings
Internal Failure
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Training and planning are critical and on-going
Appraisal Prevention
Time in process
Introduction to DOE & Application of ECHIP
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Practices of DOE
Uses statistical principles to obtain accurate results
Yields more information than one-at-a-time experiments Statistically valid design gives statistically valid results Uses confidence testing to determine significance of effectson to DOE & Application of ECHIP
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Interactions plot
What are the interactions that would effect the process? Example of Bonding Power and Bonding Time on Ball Shear Ball shear Strength (g)
Better able to “manage” the process for cost, time and quality Better able to predict the effects of adjustments of the process Better meet customer requirements
Introduction to DOE & Application of ECHIP
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Purposes of DOE
Identify key factors to design (or re-design) a process or product for better quality and efficiency.
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DOE in Manufacturing: Ball Bonding Example
Variable
Bond Power Bond Force Bond Time Temperature
Low Level High Level
30 mw 40 g 10 ms 190°C 60 mw 80 g 30 ms 240°C
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Purposes of DOE
To gain knowledge about the effects of variables (factors) in a process
Identify Input and output variables Determine optimum levels of variables Determine interactions of variables
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Practices of DOE
Leads to good engineering practice such as:
Highly structured and thoughtful design and implementation encourages good design practice. Provides a base to mathematically model a process using response surface methodology. (session 2) Promotes systematic and logical testing that validates and verifies intuition and experience. Encourages good decisions through documentation and data analysis.
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Identify DOE resource needs
Management support necessary
Time and money for training Need management perspective to see impact on the whole system Downtime, if necessary of process Material/product costs ( Wafer, Frames )
Introduction to DOE & Application of ECHIP
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