Data Analysis tool by EBA

1. Standard
Test Data
Yield
Analysis
Tool
Ertan Baykal
ertan.baykal@stericsson.com
April 2010

2. Contents
•What is STDF
•What is STDF_PRJ tool
•Tool’s Main Features
•Benchmark
2 CONFIDENTIAL 5/5/2012

3. What is STDF
The Standard Test Data Format is a
comprehensive standard for the entire
ATE industry, developed by Teradyne.
STDF is flexible enough to meet the needs
of the different testers that generate raw
test data coming from ATE.
Data analysis programs use STDF
( binary file ) to extract desired information.
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4. What is Standard Test Data Yield Analysis
Standard Test Data Yield Analysis tool enables test and
product engineers to perform fast Yield analysis and Start up Window
process characterization on their desktops, using standard
semiconductor test data files STDF.
Tool is particularly useful for test engineers, close to ATE
system. It dose not require a Data Base and DataPower
to identify and report yield issues.
ATE generates STDF file, tool opens it and analyses the
results, no need to wait for data to be inserted into Data
Base and later appear in DataPower.
Tool was developed over a year out of office hours to
enable me to do my job better and faster. Softwares used
to develop it are Windows Pascal, Advance_Grid and
TeeChart_Pro.
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5. Tool’s Main Features
Distribution Plots:
Contains main Stat Data
Box Plots:
useful for process
characterization & Matrix Lots
Analysis
Parametric test wafer map:
analyze the test gradient on
wafer to investigate process or
testing related problems
Color gradients on the distribution Tools can read multiple STDF files
Plot corresponds to gradient
Pareto Fails Charts:
On the wafer for a given parameter..
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6. Tool’s Main Features cont…
1 2 3 4 5 6 7
1 Contains Raw data.
2 Soft Ware Bin Fails
• Stores a count of the parts associated with a particular logical bin after testing.
3 Hard ware Bin Fails
• Stores a count of the parts “physically” placed in a particular bin after testing.
4 Test Synopsis Data :
• Contains the test execution and failure counts for parametric or functional tests.
5 Detailed Global information: tester, lot, operator etc…
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7. Tool’s Main Features cont…
Test summary:
Test name, limits, Fail count, Min, Max, Range, Mean, Sigma, Cpk, etc..
Copy and paste for reporting…
6
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8. Tool’s Main Features cont…
Detailed Global information:
tester, lot, operator information,
Copy and paste for reporting
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9. Tool’s Main Features cont…
Raw Data view
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10. Tool’s Main Features cont…
Yield information : good parts, failing parts, parts retested, Copy and
paste for reporting
A mouse click on YLD% or FAIL_CN cells sorts the data, useful to see
main parameters causing a yield loss.
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11. Tool’s Main Features cont…
Software Bin Fails, text or graphical format, Copy and
paste for reporting
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12. Benchmark
STDF TOOL Data Power
NO, Data to be
inserted into DATA
BASE later picked up
Does Data is avaiable immediatley after a Lot is completed? Yes by Datapower
Does it require Data Base to access Data ? NO Yes
Pareto Fails Available after extraction Time ? Yes NO *
Yield Data Available after extraction Time ? Yes NO *
Wafer Maps Available after extraction Time ? Yes NO *
Distribution Plots Available after extraction Time ? Yes NO *
* After Data extraction It requires extra steps and time
to filter data
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