Plasma 703-1-0 User manual

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ION BEAM RF SOURCES
MANUAL
ESTABLISHED 2003

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Thank you for purchasing an ion beam source from Plasma Process Group! We want your new source to operate
safely. Anyone who installs or operates this equipment should read this publication (and any other manuals)
before installing or using the ion beam source, neutralizer and power supply.
All applicable local and national codes that regulate the installation and operation of this electronic equipment
should be followed. It is your responsibility to determine the codes that apply to your area.
Please follow all applicable sections of the National Fire Code, National Electronic Code, and the codes of the
National Electrical Manufacturer’s Association (NEMA). Consult with your local government to help determine
which codes are necessary for safe installation. Failure to comply with applicable codes and standards may
result in equipment damage or serious injury to personnel.
Our equipment is designed for laboratory or production vacuum environments. The external interlock for the
ion beam source power supply should be connected to your facility to ensure maximum safety and prohibit
usage of the equipment when unsafe conditions arise. Failure to use the external interlock is considered “High
Risk Activities” where personal injury or equipment damage may result. Plasma Process Group specically
disclaims any expressed or implied warranty for High Risk Activities.
The ion beam power supply has been CE certied and the electronic discharges for the source and neutralizer
are created using industry standard radio frequency (RF) methods. Improper installation of this equipment may
result in disruptions with other sensitive electronic equipment.
If you have any questions regarding the installation and operation of this equipment, please contact us immediately at
970-663-6988 or [email protected].
We at Plasma Process Group hope that using your new ion beam source will produce rewarding results.
Copyright © 2019 by Plasma Process Group, Inc. All rights reserved.
7330 Greendale Road, Windsor, CO 80550 USA
Phone [phone] • Fax [phone]
No part of this publication may be reproduced without prior written permission
Date: October 2019 REV P1
Safety
WARNING
HAZARDOUS VOLTAGE – ion beam sources are to be serviced
and operated by trained personnel only.

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For Service or Repair please contact us at 970-663-6988 or send an email to [email protected].
Before contacting us please have ready the following information about the issue:
Many issues can be solved over the phone or email.
In the event hardware needs to be returned, all equipment, including warranty, returned to Plasma Process
Group (PPG) requires a return authorization (RA) number. Our support team will provide a return request form
with instructions to start the process. This form is also located at our website plasmaprocessgroup.com (see
Resources then Terms and Forms). Special instructions will apply to international customers.
Our workmanship warranty can be found at our website plasmaprocessgroup.com (see Resources then Terms
and Forms).
Service and Technical Support
• Product type
• Model and serial number
• Date purchased
• List of all the operating parameters
• Error messages on power supply
• Gas ow to the source, neutralizer and background
• Chamber pressure
Warranty

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This manual uses these symbols to indicate potential hazards.
ALERT - This symbol is used for tips and other pointers.
Warning Statements
Warning- Risk of Injury to Persons
is symbol is used to warn of a heavy li operation.
CAUTION
This symbol is used to alert of a potential risk to person or equip-
ment.
WARNING
This symbol illustrates a electrical shock hazard.

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Table of Contents
Chapter 1: Getting Started 6
Section 1.1: Terminology 6
Section 1.2: Overview 8
Chapter 2: Installation 11
Section 2.1: General Requirements 11
Section 2.2: Layout 12
Section 2.3: Unpacking 13
Section 2.4: Source Installation 14
Chapter 3: Specications 18
Section 3.1: Specications for RF Neutralizer (RFN) 18
Section 3.2: Specications for 6 cm RF 19
Section 3.3: Specications for 12 cm RF 20
Section 3.4: Specications for 16 cm RF 21
Section 3.5: Specications for 23 cm RF 22
Section 3.6: Specications for Linear RF 23
Section 3.7: Power Supply Specications 24
Chapter 4: Operation 25
Section 4.1: Quick Start Sequence 25
Section 4.2: Additional Resources 29
Chapter 5: Advanced Operation 30
Section 5.1: Grid Theory 30
Section 5.2: Source Ignition 36
Section 5.3: Source Ignition Sequence 38
Section 5.4: Technical Tips 39
Chapter 6: Maintenance 42
Section 6.1: Maintenance Work Station 42
Section 6.2: Schedule 43
Section 6.3: Common Wear and Tear 44
Section 6.4: Recommended Spare Parts 45
Chapter 7: Troubleshooting 46
Section 7.1: Common Issues and Quick Fixes 47
Section 7.2: Power Supply Error Codes 48
Section 7.3: RF Neutralizer (RFN) Errors 51
Section 7.4: Starting the Source 53
Section 7.5: Turning on the Beam 54
Section 7.6: Additional Resources 55
Chapter 8: Parts and Drawings 56
Section 8.1: Navigating Grid Assembly Drawings 56
Section 8.2: Part Numbers for RFN 57
Section 8.3: Part Numbers for 6 cm RF Source 58
Section 8.4: Part Numbers for 12 cm RF Source 61
Section 8.5: Part Numbers for 16 cm RF Source 64
Section 8.6: Part Numbers for 23 cm RF Source 69
Section 8.7: Part Numbers for 6x22 cm RF Source 72
Section 8.8: Part Numbers for 6x30 cm RF Source 73
Appendix A: Cleaning Guide 75
Section A.1: Molybdenum Grid Cleaning Procedure 75
Section A.2: Reassemble 78
Section A.3: Electrical Testing 82

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Ion beam technology was developed at NASA in the 1960s as a means of producing thrust on
spacecraft. Today, ion beam sources are used on vacuum systems for depositing precise thin lm
coatings of oxides, diamond-like carbon, and other useful materials on optical and mechanical
components.
This manual covers the installation and operation of radio frequency (RF) ion beam source
products we oer.
Section 1.1: Terminology
The function of an ion beam source is to produce ions
and accelerate these ions to high velocities so they
are ejected downstream from the source. The ejected
ions are directed to form a “beam” in which they all
have the same energy and can be directed to a target
or other substrate. At low energies, the ion beam is
useful for etching or cleaning parts. At high energies,
the ion beam can be used to sputter target materials.
An RF ion source package consists of the ion beam
source, an RF neutralizer (RFN), feedthroughs, power
supply(s), RF matching network, and cables. To install
the source in a vacuum system, feedthroughs are
used and these combined with additional hardware
form an interface kit.
Chapter 1: Getting Started
Ion beam striking a target.
The hardware unpacked.
ION BEAM RF SOURCES MANUAL

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ION BEAM RF SOURCES MANUAL Chapter 1: Getting Started
Depending upon the conguration, the source
may already be attached to the interface kit. This
is common for ange mounted sources. For these
cases, the matching network is also attached and the
entire assembly just requires installation. Internal
mount kits will come with individual feedthroughs
that require installation into the vacuum system
before the source can be attached.
Inside the source are the key elements for operation.
These include the gas inlet (also called gas isolator),
the RF antenna (also called coil), discharge chamber
and grids. Process gas, such as high purity Argon,
is fed into the discharge chamber. The RF antenna
will then excite free electrons causing ionization of
the process gas. A plasma is then created inside
the discharge chamber. A plasma is an electrically
conductive gas where the density of ions and
electrons are approximately equal.
All RF ion beam sources will have these same key
elements. Only the sizes and geometries will dier
for antennas, grids, and discharge chambers.
Source and interface kit assembly
Inside the source
The RF ion beam source family.

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ION BEAM RF SOURCES MANUAL Chapter 1: Getting Started
ION BEAM PARAMETERS
PARAMETER DEFINITION UNIT
Source Gas Flow Process gas delivered to the discharge chamber. sccm
RF Forward Power The RF power applied to the matching network. This controls the
ion production rate W
RF Reected Power The RF power returned from the matching network. W
Beam Voltage Positive voltage applied to the screen grid (ion energy). V
Beam Current The total ion current leaving the source. mA
Accel Voltage Negative voltage applied to the accelerator grid. V
Accel Current Current collected by accelerator grid (charge-exchange). mA
A/B Ratio Ratio of accel to beam current. Typical A/B is < 10%. %
Section 1.2: Overview
The schematic below illustrates how the key elements work inside the source. Process gas is supplied to
the discharge chamber. The RF antenna is tuned using the matching network where its voltages can reach
upwards of ±2500 V. The oscillating eld will excite free electrons that can ionize the process gas and sustain
a plasma discharge (ions and electrons). Ions created in the discharge chamber that drift towards the grids
are then accelerated to high velocities with electrostatic potential applied to the grids. The screen grid is
biased positive, the accelerator grid is biased negative and the decelerator grid is grounded.
Electrical schematic for the RF ion beam source

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ION BEAM RF SOURCES MANUAL Chapter 1: Getting Started
The grids, which control the ion optics, will come in
dierent shapes, sizes and materials. They can be
at (i.e. graphite) or dished (i.e. molybdenum) to
promote beam shape and trajectories. The inner
most grid is called the screen grid (biased positive)
and the middle grid is called the accelerator (biased
negative). Most grid assemblies will have 3 grids
where the decelerator will act as a shield to the other
two grids and capture process material coming back
to the source. Additional information about the grid
operation and design can be found in Chapter 5.
A neutralizer is placed downstream from the source
where it emits electrons to balance the number
of positive ions which leave the source. The RFN
operates in a similar fashion to the source as it
requires process gas, has an RF antenna and its own
matching network. Please refer to its manual for a
detailed description of its operation and additional
information.
The RFN needs to be placed so that its electrons can
couple (or “see”) the ion beam. It is very important
that these electrons have a close (about 150 mm),
unobstructed path to the beam to ensure stable,
noise free operation. The RFN should also be located
away from strong magnets or shielded from magnetic
elds using 400 series stainless steel. A common
challenge will be to protect the RFN from process
material that can coat its keeper - but allow for
electrons to couple.
Electrons from the neutralizer do not recombine
with source ions, rather they provide space-charge-
neutralization for the downstream plasma. Under
normal operation, the neutralizer will emit between
125% to 200% of the measured beam current. In this
fashion substrates or targets downstream will not
suer damage due to arcing or surface charging.
Typical grids before assembly
Place the RFN in close proximity to the ion beam
The RFN will emit more electrons than ions from
the source

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ION BEAM RF SOURCES MANUAL Chapter 1: Getting Started
The source and RFN are both controlled using
the I-BEAM power supply. The I-BEAM supply is
connected to the source, RFN and it will monitor the
source matching network controller. There are three
modes of control. These are “Manual” which provides
full RF control, “Local” which allows direct beam
current control, and “Remote” for system interface.
Please refer to its manual for a complete description
and additional information. Specics on the power
supply operational features will be discussed in
Chapters 4 and 5 of this manual. Chapter 5 also has
tech tips for the source, RFN, and I-BEAM.
The table below are the critical operating parameters
for the RFN. The I-BEAM ion source controller
NEUTRALIZER PARAMETERS
PARAMETER DEFINITION UNIT
RFN Gas Flow Gas delivered to the neutralizer. sccm
RFN Forward Power The RF power applied to the matching network. W
RFN Reected Power The RF power reected from the matching network. W
Keeper Current Discharge current between keeper and collector. Typical is
300 mA. mA
Keeper Voltage Voltage applied to keeper. Lower than 30 V is preferred. V
Neutralizer Emission
Current The electron current emitted by the neutralizer. mA
E/B Ratio Ratio of neutralizer emission to beam current. Typical E/B
is 125% or greater to minimize surface charging and arcing. %