Taguchi Method and SPC system
in Semiconductor Manufacturing
Chin-Yuan Chen 陳志遠
Quality Manufactory
Advance Semiconductor Engineering Manufacturing Company, Ltd
Fisher_Chen@aseglobal.com
April 30, 2010
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Abstract:
This presentation will cover the following topics, Taguchi Method
Application in Assembly and Testing Site, SPC appliation system in
Assembly process.
• First, to present basic process introduction of semiconductor of
assembly and testing. Taguchi Methodology and examples of
assembly/test will be shown. To assist engineers to find root casue
and enhance process capability, reduce variance, improve process
capacity. Our company offer complete statistic training to new
engineers.
• However, SPC methodology is most important tool for process
control. To understand SPC concept, QC tools and OCAP(Out of
Control Action Plan) become basic request of engineers.
• JMP software
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The statistical software in ASE
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The statistical software in ASE
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Content:
1. Assembly/Test brief introduction
2. Taguchi Method in test site
- Enhance wrinkle bump yield
3. Taguchi Method in Assembly site
- Gold Wire Diameter Reduction Evaluation
4. SPC in Assembly site
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1. Assembly/Test brief
introduction
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What common point
they had?
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ASE Vision:The Comprehensive Solution
Final Test
Module, Board
Assembly &
Test (DMS)
Assembly
Wafer
Bumping/Probing
Foundry
Materials
Circuit Design
Engineering Test
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Brief Assembly Process
研磨
黏晶片
晶片切割
缺點檢查
. .. . .
. ...
..
.
晶圓 (研磨後)
已切割
缺點檢查
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Brief Assembly Process
上銀膠
黏晶粒
銲線
. .. . .
. ...
..
.
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Brief Assembly Process
銲線缺點檢驗
金線直徑(20um)約頭髮直徑(40um)的一半
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Brief Assembly Process
封膠
正印
植球
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Brief Test Process
測試
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Brief Test Process
Contact pushor
Contact
blade
Dut
socket
Loadboard
Handler
TESTER
TEST HEAD
Interface
晶圓
Wafer
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2. Taguchi Method in test site
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Bump Status Check
Wrinkle bump issue
Low Yield
Normal bump
Wrinkle bump
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Test Pin
Test Pin
Normal Bump
Wrinkle Bump
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Normal Bump
Wrinkle Bump
If you are engineer, then what will you improve?
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Hint
Good Yield
Good Contact
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Normal Bump
Wrinkle Bump
Contact deeper (Enhance Over Drive)
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Taguchi Method
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Taguchi Method - Analysis
L9 (34 )直交表
To choose L9 Taguchi experiment matrix and consider two response(y) as
above table.
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Taguchi Method- Analysis
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3. Taguchi Method in
Assembly site
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History
1. Customer want cost saving with device,
and to reduce gold wire diameter.
2. Current diameter is 25um, customer
request to reduce as 20 um.
3. Current composition is Au, customer need
to replace by Au-Pb.
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Structure
652 golden wire
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Taguchi Matrix
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Taguchi Analysis Result
On Desirability Functions
The desirability functions are smooth piecewise
functions that are crafted to fit the control points.
The minimize and maximize functions are three-part
piecewise smooth functions that have exponential tails
and a cubic middle.
The target function is a piecewise function that is a
scale multiple of a normal density on either side of the
target (with different curves on each side), which is
also piecewise smooth and fit to the control points.
These choices give the functions good behavior as the
desirability values switch between the maximize, target,
and minimize values. For completeness, we
implemented the upside-down target also.
JMP doesn't use the Derringer and Suich functional
forms. Since they are not smooth, they do not always
work well with JMP's optimization algorithm.
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4. SPC in Assembly site
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height
Quantil es
50
55
60
65
Normal(62.55, 4. 24234)
70
100.0% maximum
99. 5%
97. 5%
90. 0%
75. 0%
quart ile
50. 0%
median
25. 0%
quart ile
10. 0%
2.5%
0.5%
0.0%
minimum
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Moments
70. 000
70. 000
69. 975
68. 000
65. 000
63. 000
60. 250
56. 200
51. 025
51. 000
51. 000
Mean
St d Dev
St d Err Mean
upper 95% Mean
lower 95% Mean
N
Sum W gt
Sum
Varianc e
Sk ewnes s
Kurt os is
CV
N Miss ing
Fi tted Nor mal
62. 55
4.2423385
0.6707726
63. 906766
61. 193234
40
40
2502
17. 997436
-0. 781526
0.8768985
6.7823157
0
Parameter Estimates
Type
Parameter
Loc at ion £g
D ispersion£m
Esti mate Lower 95% U pper 95%
62. 55
61. 193234 63. 906766
4.2423385 3.4751583 5.4473132
Goodness-of-Fi t Test
Shapiro-W ilk W Tes t
W
Prob<W
0.953459
0.0998
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N ot e: H o = The dat a is f rom the N ormal dist ribut ion. Small
p-v alues reject H o.
授權書
範例內容(Enhance wrinkle bump yield, Gold Wire Diameter Reduction Evaluation)
的原作者之授權
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攜帶物品
八吋晶圓(破片)乙片
PBGA(正印已處理過)四顆
PBGA 空基版四條
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