Digital PECVD Machine Design and Construction

Zlatan Ceric

William Edwards

Timothy Gurtler

David Ogden

Quan Tran

Date:12/10/2010

Project Overview

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

Continuously monitor chamber vacuum pressure, RF power, and gas flow rate

Automated the polymer deposition process

Allows for future process modification through HMI

RIE to PECVD Conversion

Removed turbo pump

Use one chamber pressure sensor instead of two

Removed old chamber heater

Remapped wires to integrate new design

Edited PLC and HMI code to reflect all changes

System Hierarchy

HMI

RF Power

Mech Pump

MFC

Matching Network

Legend

Input to PLC

Output from PLC

Mech Conn.

PLC

Chamber

Mechanical Pump

Mass Flow Controllers

RF Power System

Chassis Construction

Gator Jaw is the material used to build the stand

It is customizable and easily changed if needed

Plates can be mounted to the frame to provided a surface for components to mount

Component Mounting

Din rail provides a simple mounting solution

Standard 35mm width used widely in industrial control systems

PLC was designed to mount onto this type of rail

Power supply and terminal blocks also mount to it

Centralized Signal Testing

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

Each Input into the PLC was forced on to ensure each component was working properly

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 Working with new programs and languages:

– RSLogix5000 with Ladder Logic– FactoryTalk View Studio

Interfacing with analog, digital, and serial connections

Inability to test and debug software before machine was fully assembled

Not able to implement “Trending” function due to time constraints

Subsystems Interaction

Subsystems need a way to interact with each other and PLC

Require customized cables

Problems with Pneumatics

Problem: No Documentation

Solution: Called Technical Support

Problem: Solenoid was not working properly

Solution: Craig Fox came out to

help solve the problems

Problems with RF Power

Problem: RF Power would not respond

Solution: Called Tech Support to resolve problem

Problem: High Power could not be achieved

Solution: Replaced RF Power Supply

Budget and Cost

Project is exclusively design for Ga Tech NRC and cannot be used for mass production

Parts were donated, salvaged, and funded by:– Ga Tech NRC– Rockwell Automation

A conservative estimate cost of $135,000 including hardware and labor/testing for completed project

Cost Breakdown

Labor & Testing Assume average GT ECE

graduate earns $65K annually

Project includes 5 design and implementation members

Estimated labor and testing of $100K

Hardware

Plasma Chamber $2,500

RF Power Supply $6,500

Frame $2,000

MFC x4 $8,000

Throttle Valve $5,000

• Major components

Future Work: Intended Machine Use

M. Bakir 2008

Options: •Deep UV lithography•Electron Beam Lithography•FEL/ARLP X-Ray Lithography•Nano Imprint Lithography

Topographic negative of structure will will be constructed with electron beam lithographyOrganic Gas will deposit non stick polymer on moldMold will be used as press to relief desired structureAntistick coating will have to be reapplied after several uses (~3)

Future Work: Additional Machine Use

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?