© 2013 TriQuint Semiconductor, Inc. Automation of RGAs and Sensors for FDC of PVD Metal Thin Film Processing 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 BISTel America, 4633 Old Ironsides Dr, Suite 300, Santa Clara, CA BISTel Inc. 2F, Jeongpung Bldg, Seocho-dong, Seocho-gu, Seoul, Korea

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 Torr © 2013 TriQuint Semiconductor, Inc.

Pressure Range of PVD Process Various Vacuum Mediums* © 2013 TriQuint Semiconductor, Inc. *

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. © 2013 TriQuint Semiconductor, Inc.

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 Y-TAP PVD Controller FDC RGA Application RF Application Pump Application RGA Control Libraries RF Data Collection Library Pump Data Collection Library Pump PM1 PM2 PM3PM4 PM5 PM6 RF RGA Chamber Processing Status Wafer Processing Status of Each Chamber Trace Data © 2013 TriQuint Semiconductor, Inc.

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? © 2013 TriQuint Semiconductor, Inc.

What is Gained? Context for sensors that are not available on processing chambers. © 2013 TriQuint Semiconductor, Inc.

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 Torr Customized RGA filament control schemes –P < 9.0 x Torr, filament is always on –P > 9.0 x Torr, filament on only for a short time (10sec.) at end of wafer process, otherwise filament is off © 2013 TriQuint Semiconductor, Inc.

Real time control with integrated sensors like the RGA Filament Status (On) Chamber Pressure AMU 28 (N 2 ) Example of RGA control to sample at the end of a process run. Process is complete. FDC sends the command to ignite the RGA filament. © 2013 TriQuint Semiconductor, Inc.

RGA contaminated bottle controlled test © 2013 TriQuint Semiconductor, Inc. A small Ar bottle that was purposely contaminated with 1600ppm of N2 was connected to a PVD chamber as a controlled test. N2 Contamination Rs Sample Time Pressure * The Ar36 isotope was chosen for the graph instead of Ar40 because of the signal magnitude relative to the magnitude of N 2.

Example 1: Real Time RGA Alarm © 2013 TriQuint Semiconductor, Inc. Ar should be present. O 2 and H 2 are baseline signals. N 2 peak (pulse) detected.

Example 2: Chamber Lid Leak RGA Trace © 2013 TriQuint Semiconductor, Inc. AMU28 (N2)- Red  Chamber lid leak Blue  Normal

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 © 2013 TriQuint Semiconductor, Inc.

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.