Digital PECVD Machine Design and
Construction
Zlatan Ceric
William Edwards
Timothy Gurtler
David Ogden
Quan Tran
Date:12/10/2010
Project Overview
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Contracted by Nanotechnology Research Center
Converted existing RIE to PECVD machine
Automation of process eliminates the need for
constant human monitoring
Cost of Hardware: $35,000
Built base model for NRC modification
Final Product
Design Objectives
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Continuously monitor chamber vacuum
pressure, RF power, and gas flow rate
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Automated the polymer deposition process
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Allows for future process modification through
HMI
RIE to PECVD Conversion
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Removed turbo pump
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Use one chamber pressure sensor instead of two
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Removed old chamber heater
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Remapped wires to integrate new design
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Edited PLC and HMI code to reflect all changes
System Hierarchy
RF
Power
Matching
Network
PLC
Chamber
HMI
Mech
Pump
MFC
Legend
Mech Conn.
Output from PLC
Input to PLC
Mechanical Pump
Mass Flow Controllers
RF Power System
Chassis Construction
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Gator Jaw is the material
used to build the stand
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It is customizable and
easily changed if needed
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Plates can be mounted
to the frame to provided
a surface for
components to mount
Component Mounting
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Din rail provides a simple
mounting solution
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Standard 35mm width used
widely in industrial control
systems
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PLC was designed to
mount onto this type of rail
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Power supply and terminal
blocks also mount to it
Centralized Signal Testing
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Over 70 signals are required
for the PLC to manage
Having terminal blocks gives a
convenient location to test the
signals
Mounting them onto the din
rail gives a clean look for the
machine
Future manipulations of the
machine will also be more
convenient
Testing the Machine

Wire continuity was first check to ensure each
component was properly connected
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Each Input into the PLC was forced on to ensure
each component was working properly
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Feedback was compared between components and
HMI Display
Set Point Feedback
• Pressure is required
to stay within 10%
• Gas Flow Rate is
required to stay within 1%
• RF
Power is required to
stay within 5%
PLC Operational Flow Chart
HMI Screen Capture
Recipe Input Capture
Power Input Capture
Coding Challenges
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Working with new programs and languages:
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RSLogix5000 with Ladder Logic
FactoryTalk View Studio
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Interfacing with analog, digital, and serial
connections
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Inability to test and debug software before machine
was fully assembled
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Not able to implement “Trending” function due to
time constraints
Subsystems Interaction
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Subsystems need a way to interact with each other
and PLC
Require customized cables
Problems with Pneumatics
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Problem: No Documentation
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Solution: Called Technical
Support
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Problem: Solenoid was not
working properly
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Solution: Craig Fox came out to
help solve the problems
Problems with RF Power
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Problem: RF Power
would not respond
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Solution: Called Tech
Support to resolve
problem
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Problem: High Power
could not be achieved
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Solution: Replaced RF
Power Supply
Budget and Cost
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Project is exclusively design for Ga Tech NRC and
cannot be used for mass production
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Parts were donated, salvaged, and funded by:
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Ga Tech NRC
Rockwell Automation
A conservative estimate cost of $135,000 including
hardware and labor/testing for completed project
Cost Breakdown
Hardware
• Major components
Plasma Chamber
$2,500
RF Power Supply
$6,500
Frame
$2,000
MFC x4
$8,000
Throttle Valve
$5,000
Labor & Testing
 Assume average GT ECE
graduate earns $65K
annually
 Project includes 5 design
and implementation
members
 Estimated labor and
testing of $100K
Future Work: Intended Machine Use
M. Bakir 2008
Options: •Deep UV lithography
•Electron Beam Lithography
•FEL/ARLP X-Ray Lithography
•Nano Imprint Lithography
Future Work: Additional Machine Use
Topographic negative of structure will will be constructed with electron beam lithography
Organic Gas will deposit non stick polymer on mold
Mold will be used as press to relief desired structure
Antistick coating will have to be reapplied after several uses (~3)
Future Work: Diagnostic and Expansion
•Plasma Density Test
•Additional internal real
estate available:
•MFCs
•Turbo
•Heating System
•Magnetic field module
Video Demonstration
Questions or Comments?