Arif Choudhury 1 , Eric McCormick 1 , Guy Takayesu 1 ,
Keith Han 3 , Alex Lee 3 , Young Hwan Lee 3 , Justin
Wong 2 , and John Yoo 2
1 TriQuint Semiconductor Corporation, 500 W Renner Rd, Richardson, Texas, USA 75080
2 BISTel America, 4633 Old Ironsides Dr, Suite 300, Santa Clara, CA 95054
3 BISTel Inc. 2F, Jeongpung Bldg, 1341-3 Seocho-dong, Seocho-gu, Seoul, Korea 137-070
© 2013 TriQuint Semiconductor, Inc.

Content
• Introduction
– RGA Usage In PVD Process
• Applications of RGA in Manufacturing
• Architecture of FDC and Sensors
• RGA Filament Control Schemes
• Examples of FDC with RGA
• Future Work
• Conclusion
© 2013 TriQuint Semiconductor, Inc.

Introduction of RGA and RGA Usage in PVD
• The RGA is commonly used to identify atomic and molecular species in a high vacuum environment.
• In the PVD process the RGA is commonly used to monitor contamination before and during the process.
– Screens the incoming substrate for resist residue
– Monitoring process gases
• The RGA is very sensitive, it can detect low pressure contaminants in 10 -14 Torr
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Pressure Range of PVD Process
• Various Vacuum Mediums*
* http://www.eng.tau.ac.il/~yosish/courses/vlsi.html
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RGA Advantage
• The RGA is an ideal tool for monitoring of PVD process because it can detect subtle changes in the chamber condition, i.e. contamination
• The mean free path increases at high vacuum so the probability of detecting a contaminant goes up.
• Can report the probable species of molecule present in the PVD chamber.
• Possible real time detection of contaminants or chamber leaks.
• Not reliant on metrology feedback.
© 2013 TriQuint Semiconductor, Inc.

Applications of RGA in Manufacturing
• Baseline Spectrum
– Spectrum scan of a known good chamber or condition
• Spectrum Analysis (Troubleshooting)
– Analyzing the species that exist inside a chamber that is having some unknown issue
• He Leak Checking
– Standard practice after a PVD target change
• Stand Alone Process Analysis
– The RGA manufacturers offer stand alone packages for near real time analysis of spectrum as the tool is running.
– Typically not integrated into the house FDC system.
– High cost for the software.
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Benefits of Integrating RGA with FDC
 Having one system that can connect to multiple components and interdict in the event of an incident saves the expense of having multiple FDC systems for each component
 Adding RGAs from different manufacturers that are not supported by the tool OEMs.
© 2013 TriQuint Semiconductor, Inc.

Architecture of FDC and Sensors
FDC
Pump
Y-TAP
Chamber Processing Status RGA
Application
RGA Control
Libraries
RF
Application
RF Data
Collection
Library
• Wafer Processing Status of
Each Chamber
• Trace Data
PM1
PVD
Controller
PM6
RF
PM2 PM5
Pump
Application
Pump Data
Collection
Library
PM3 PM4
Pump
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Component Connections
• Tool SVIDs  HSMS Ethernet
• RF Monitor  A to D device to receive the analog signals and pass them to the
Ethernet
• Pump data  RS-232 hub to Ethernet convertor
• Others?
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What is Gained?
• Context for sensors that are not available on processing chambers.
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RGA Filament Control Schemes
• RGA operation constraint
– Open Ion Source mode of RGA operation
– RGA operating pressure region is limited
– Filament tripped off when P > 9.0 x 10 -3 Torr
• Customized RGA filament control schemes
– P < 9.0 x 10 -3 Torr, filament is always on
– P > 9.0 x 10 -3 Torr, filament on only for a short time (10sec.) at end of wafer process, otherwise filament is off
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Real time control with integrated sensors like the RGA
Chamber Pressure Filament Status
(On)
•Example of RGA control to sample at the end of a process run.
AMU 28 (N
2
)
Process is complete. FDC sends the command to ignite the RGA filament.
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RGA contaminated bottle controlled test
• A small Ar bottle that was purposely contaminated with
1600ppm of N2 was connected to a PVD chamber as a controlled test.
1,40E-05
1,20E-05
1,00E-05
8,00E-06
6,00E-06
4,00E-06
2,00E-06
0,00E+00
Ar36 Test
Bottle
N2 Test
Bottle
Ar36 House
Bottle
N2 House
Bottle
N2
Contamination
1 11 21 31 41 51 61 71
Time
*
The Ar36 isotope was chosen for the graph instead of Ar40 because of the signal magnitude relative to the magnitude of N
2
.
Sample
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Example 1: Real Time RGA Alarm
•Ar should be present.
•O
2 and H
2 signals.
•N
2 are baseline peak (pulse) detected.
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Example 2: Chamber Lid Leak RGA Trace
AMU28 (N2)Red  Chamber lid leak
Blue  Normal
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Future Work
• Implementing RGA at house Ar gas supply
– Detect problem at time close to t
0
– Minimize recovery
• Adding Real-time leak test recipes for maintenance and operators
– Post chamber recovery
– Weekly chamber integrity check
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Conclusion
• There is great value in integrating RGAs and other sensors into an in-house FDC system.
– Sensor Control
– Real time context with existing tool parameters
– Real time detection
© 2013 TriQuint Semiconductor, Inc.

Acknowledgement
• The authors want to express their appreciations for the valuable inputs on this project from Romek Bobkowski and Richard
Groom, both of TriQuint Semiconductor
Corporation on PVD processing and RGA operation respectively.
© 2013 TriQuint Semiconductor, Inc.

© 2013 TriQuint Semiconductor, Inc.