Advanced Energy Industries RFX 600 User manual

THE
ADVANCED ENERGY®
RFX 600 GENERATOR
User Manual
ADVANCED ENERGY
INDUSTRIES, INC
1600 Prospect Parkway
Fort Collins. Colorado 80525
[phone]
Telex #45-0938
PN: 5705008-8
June 1991

To ensure years of dependable service, Advanced Energy® products are
thoroughly tested and designed to be among the most reliable and highest
quality systems available worldwide. All parts and labor carry our standard
1-year warranty.
For Customer Service, call:
AE, Colorado office
AE, California office
AE, Japanese office
AE, German office
all others
[phone] (24-hour line)
Fax: [phone]
[phone] (8 a.m. to 5p.m. Pacific
Standard Time -California only)
Fax: [phone]
81 (03) 3222-1311
Fax: [phone]
49 [phone]
Fax: [phone]
contact your local service center-see the list
on the next page
©1990, Advanced Energy Industries, Inc
All rights reserved. Printed in the United States of America. This manual is
supplied to enable the reader to safely install, operate, and service the
equipment described herein. Making copies of any part of this manual for any
purpose other than these is aviolation of U.S. copyright law.
In the interest of providing even better equipment, Advanced Energy
Industries, Inc., reserves the right to make product changes without
notification or obligation.
For more information, write Advanced Energy Industries, Inc., 1600 Prospect
Parkway, Fort Collins, CO 80525.

l.
2.
3.
4.
5.
safe'ty .
General ~iption.
Specifications .
Front Panel Display
Rear Panel Display.
TABlE OF CONI'ENI'S
Page No.
6
7
7
9
9
6 • Connectors..................................... 10
7. Diagnostic Connector Table
8.
9.
Input PcMer Connectors .
Analog/digital I/O Connections.
Pin-description Table ..
Signal ~iptions ....
D:: Bias.
D:: Bias Regulation ...
First Time Operation.
Unpacking
start-up ....•.••.
10
10
10
12
16
17
18
20
20
20
10.
Troubleshooting .
21
Warranty
3

****** WARNING ******
SAFE O~ IRXE:IJRES AND IRJP!:R lEE OF 'lliE mJIIMENI' ARE '!HE
RESKNSmn..r.I'Y' OF 'mE USER OF 'IRIS SYSTEM.
Advanced Energy Irrlustries, Inc. provides information on its prcrlucts arrl
associates hazards, but it assumes no responsibility for the after sale
operation arrl safety practices.
AIL PERSONNEL WHO IDRK wrrn OR ARE EXFOSED TO '!HIS ECPIfMENT MUST TAKE
PRECAurIONS TO PROTECT 'THEMSELVES AGArnST Fa3SIBIE SERICUS AND/OR FATAL EODILY
INJURY.
5

1. SAFE'IY
'!be high voltage nature of the outp..rt of these ~ sut=Plies dictates the use
of caution when near the ootp.,rt pa...'er connection.
Precautic:ns:
1) Make certain that the chassis is properly grc:mrled. 'lEE GR.XJND ~OO
IR:JVIIE) SB:lJI.D lUI' BE IEFEATEJ!
2) '!be ootpJt connector is no:rna1.1y grourrled. VOIXllGE lEVElS Kl? 'lliE a::NNE:CIUR
MAY BE M::.RE 'llWl 1000 VOIll'S I:IJRn«; O~CN.
All internal adjustments may be made with the tq:> cover rercxwed but with the
safety plexiglass shield in place. After adjustments are completed, the top
cover should be replace::1 prior to turrJ.irB on the po.ver supply.
6

2. GENERAL DESCRIPTION
The RFX 600 is a two-stage power generator using aFetpower™
modular power amplifier and a switchmode dc power supply for main
power and control. The RFX is designed for 80% reflected power
capability. It regulates output power using either forward power or
dc bias of the load.
Its features allow it to be used alone or in combination with other
supplies (through common exciter mode) in such configurations as RF
with RF bias, RF with dc bias, and dc with RF bias.
3. SPCIFICATIONS
Power Output: 600 watts maximum into a 50 ohm load.
Harmonic Distortion: All harmonics are more than 50dB below the
fundamental. Noise, hum and ripple are down by 30dB or greater
below the fundamental.
Freguency: 13.56MHz ± 0.005%
Output Impedance: 50 ohms
output Power Regulation:
variation from 1: 1 to
limits).
± 3% of power setting for any load VSWR
10: 1 resistive (wi thin auto protection
Load Mismatch Tolerance:
mismatch without failure.
continuous operation into any load
Pulsed Operation: Frequency range from zero to 10KHz maximum.
Rise and fall times are less than 2.0 microseconds. PUlsing input
is CMOS 15V compatible. Unit is capable of simultaneous and
independent RF amplitude control and pulse operation.
Protection: Automatic foldback occurs when voltage, current or
dissipation exceeds preset limits. Unit capable of up to 400 watts
reflected power mismatch without foldback. Unit is completely
protected from hardware damage due to open outputs.
RF Power Control: 0 to 600 watts with front panel control or
remote 0 to 5 volt command.
Maximum Power Limit: Adjustable limit from zero to maximum output
prevents excessive output during remote operation. Front panel
setscrew adj ustment. setting may be observed on front panel
digital display.
Automatic Forward Power Setting:
externally controlled.
o to 600 watts internally or
7

Efficiencv: Variable switchmode dc input combined with Class D
Fetpower™ output provides a minimum 60% overall efficiency from 100
watts to 600 watts output into 50 ohms resistive.
Regulation: Forward power or dc bias of the load.
Input Power: 115 VAC + 10% or 230 VAC ± 10% single phase, 50/60
Hz.
Dual Supply operation: unit may operate either as master or slave
or independent mode by logic level selection through a user
connector on the rear panel (common exciter -"CEX TOGGLE") .
Remote Operation: A user connector (25-pin subminiature D-type) is
provided on the rear panel to allow remote operation or computer
interface.
Diaqnostic Connector: Rear panel subminiature (IS-pin subminiature
D-type) connector provides sufficient information to troubleshoot
a problem to an internal module level without the need to open the
cover.
Cooling: Forced air; maximum inlet ambient temperature is 40°C.
Temperature monitors protect the unit from fan failure or airflow
blockage.
Size:
6.97 in. (17.70 cm) Height
8.50 in. (21.59 cm) Width*
17.75 in (45.09 cm) Deep
*Add 2 inches (5.08 cm) to include removable rack ears
Weight: 26.5 lbs. (12 Kg)
RF Output Connector: Type "N"
8

4. FR:NI' PANEL DISPIAY
Control
IUiER - energizes unit. FWRD FWR (left) display) an:l REFL FWR (right display)
light up.
Displays
lEFT DISPIAY - controls status of left display. Each ti.ne the push button is
pressed, the display cycles tl1rc:xJgh FWRD FWR, an::i OC BIAS.
RIaII' DISPIAY - controls status of right display. Each ti.ne the push button is
pressed, the display cycles tl1rc:xJgh REFL FWR, MAX FWR an:l HiASE ANGLE.
Re;:rulation
FWD RtlR 1.CW) :Rtm - provides forward ~ regulation control.
OC BIAS LeW) :Rtm - provides dc bias regulation control. Hole above this push
button is a set screw adjustment to scale the dc Bias Control from 0-1000.
FWD p,.m;oc BIAS - pressed t.cxjether provides a load pa.ver regulation control.
5. REAR PANEL DISPlAY
2 aJC Connectors:
CEX cur - 13 .56MHz outp.rt signal frem the exciter sub-assernbly. Used in dual
system operation as a master outp.J.t to keep both units in tylase.
CEX rn - 13.56MHz inp.rt. signal to the pa.ver anplifier sub-assernbly of the
slaved unit in a dual system to keep both units in ~.
Circuit Breaker
The circuit breaker must be on to operate the unit.
9

Irn:::yt Pc:1Ner Connections
'Ihe st:.arrlard inp..It. ~ is 115V, 8. SA, sin~Ie-P"Jase, SO/60Hz.
Analcx:J/digital 110 Connections
'Ihe user I/O interface uses a 2S-pin, D-type connector. All analcg signals are
O-S V in am out. All digital signals are 0-IS V ODS carpatible.
Pin-descri.ptiCl1 Table
Pin
Narre Description
See page
1
OC BIAS.A +(+) Differential analcg feedback
12
i.np..It. for de bias regulation.
2 OC BIAS.A -
(-)
Differential analcg feed back
12
input for de bias regulation.
3OFF/RESET.D Digital rerrote input off/reset
12
CCil'll'l'aIrl. Referenced to pin 19.
4 ON.D* Digital rerrote input on e::atIrlEl"rl.
12
Reference::1 to pin 19.
SroI..SE
ON.D Digital rerrote input p.llse output 13
CCil'll'l'aIrl. Ref erence::1 to pin 19.
6CEX 'ItX3GLE. D*
Digital input enable for cornroc>n
13
exciter. Referenced to pin 19.
7 FHASE ANGIE.A Analcg input representation of phase
13
angle. Referenced to pin 18.
8
FHASE.D (+) (-)
Digi tal input representation in::licating
13
the sign of the P1ase angle, based on a
user-provided signal. Reference::J. to pin 19.
9
PIASMA.D Digital input in:iication of plasma
13
presence fran ATX tuner. Referenced
to pin 19.
10 I.DAD
~ ill.A
Analcg inplt representation of load
13
p:JWer, based on a user-provided signal.
Referenced to pin 18.
10

pin
Name
rescription
see page
11
REMJI'E PRX;RAM. A
Analc:x;r rerrote inp.It poNer adjust. 14
IEVEL
Referenced to pin 18.
12 'IUNER ARC. D
Digi tal inp.rt: in:lication of d1.amber
14
SENSE*
ARC, based on a user-providerl signal.
Referenced to pin 19.
13 rnrI..K.D
User access to digital interlock 14
strirg. Referenced to pin 19.
14 REFlECI'ED.A
Analc:x;r out:p..It representation of 14
fCWER
reflected po.Yer. Referenced to pin 18.
15 WAD ~.A
Analc:x;r output representation of 14
load power, baserl on a user-provided
signal. Referenced to pin 18.
16 OC BIAS.A
Analc:x;r output representation of 15
d1.amber de bias measured. by user.
Referenced to pin 18.
17 FDIMARD fCWER. A
Analc:x;r output representation of 15
forward power. Referenced to pin 18.
18
SIGNAL C01M)N
caraton of all analc:x;r inp.rtjoutput
15
signals.
19
FeWER C01M)N
Digital am control cornrt'¥Jn.
15
20 'IUNER
OK.D
Digital input in:lication of
15
satisfactory tuner operation from
ATX tuner. Referenced to pin 19.
21 NOr USED
22 NO!' USED
23 NO!' USED
24 NO!' USED
25
NO!' USED
*l'Eg;ltive ~ lcgie
11

Signal Descriptions: User 1/0 Pins
pin 1. dc BIAS.A +
The analog dc Bias (+) connection is the positive input to a
differential operational amplifier for scaled feedback from
the chamber. To use this input, a voltage divider of 200:1
should be established across the chamber electrodes. This
ratio will provide 5 volts dc feedback at 1000 volts dc
chamber bias. The maximum working voltage of the connection
is 10 volts above ground. The more positive of the two
feedback leads should be connected at this pin.
pin 2. DC BIAS.A (-)
The analog dc Bias (-) connection is the negative input to a
differential operation amplifier for scaled feedback from the
chamber. To use this input a voltage divider of 200:1 should
be established across the chamber electrodes. This ratio
will provide 5 volts de feedback at 1000 volts dc chamber
bias. The maximum working voltage of the connection is 10
volts below ground. The less positive of the two feedback
leads should be connected at this pin.
pin 3. OFF/RESET.D
The remote digital OFF/RESET command duplicates the RF off of
the front panel. This function overrides all other commands
and forces the RFX drive to turn off, opens the main
contactor and resets the interlock. A continuous digital low
command (contact closure to power common, user Pin 19) is
required to override the off command. The internal circuit
has a 15 volt pull-up on it to provide the OFF command when
contact closure to Pin 19 is interrupted.
The user connector plug shipped with a new RFX power supply
has a jumper wire installed between OFF/RESET.D and power
common. This will override the OFF command when this plug is
installed.
pin 4. ON.D
The remote digital on command duplicates the RF on function
of the front panel, when remote control has been selected at
the front panel. A momentary contact closure of D. on to
power common (User Pin 19) will cause RFX drive to turn on if
OFF/RESET.D has been overridden. (See pin 3, OFF/RESET.D.)
12

A two-wire on command is possible with ON.D and OFF/RESET.D
connected together. To accomplish this both must be
connected to power common (User Pin 19) simultaneously to
turn the RFX drive on.
pin 5. PULSE ON.A
This digital input enables the user to pulse the 13.56MHz
output at rates up to 10KHz and duty cycles from 0-100%.
To pulse the output off, a digital low must be provided at
this control pin. To pulse the output on, a +15 volts signal
must be provided at this control pin.
pin 6. CEX TOGGLE.D
The digital common exciter toggle command enables the CEX in
port, on the rear of the RFX supply. This command
simultaneously disables the exciter within this power supply
allowing for acommon exciter signal to drive both supplies
in synchronization through the CEX port. (Refer to the
section pin 16, DC BIAS.A on page 15).
pin 7. PHASE ANGLE. A
Analog phase angle is an input representing the phase angle
between the output voltage and current. This is a zero to 0-
5 volt signal indicating 0-90 degrees.
pin 8. PHASE.D (+) (-)
Digital phase (+) (-) is an input representing the sign of
the phase angle between the output voltage and current. A
digital low indicates a voltage lag of a capacitive load.
pin 9. PLASMA. D
The digital plasma signal is an input from the ATX tuner
indicating that the ATX tuner has sensed the presents of a
plasma in the chamber.
pin 10. LOAD POWER IN.A
The analog load power signal is an input representing load
power. This analog signal is scaled such that 0-5 volts
equals 0 to full power rating.
13

pin 11. REMOTE PROGRAM LEVEL.A
Analog remote program level is a user input for remote
control of the RFX output. To enable this input, "Remote
Signal" must be selected at the front panel. An analog 0-5
volt signal will program 0 to full output of the RFX. This
input signal must be referenced to signal common, user pin
18.
pin 12. TUNER ARC SENSE. D
The digital tuner arc signal is an input indicating a chamber
arc. This is a digital low active signal.
pin 13. INTLK.D
The interlock function allows the user to gain access to the
interlock string. With the string not satisfied the main
contactor will not close, or if closed, will begin opening
with 1 millisecond of the break. To satisfy the interlock
command, contact closure to power common, user pin 19 must be
made. When the interlock string has been satisfied, the
"INTLK" status indicator on the front panel will be
illuminated.
The user connector plug shipped with a new RFX power supply
has a jumper wire installed between INTLK.D and power common.
This will establish the interlock string when this plug is
installed, enabling the unit to recognize an ON command.
pin 14. REFLECTED POWER.A
The analog reflected power signal is a scaled output signal
representing reflected power as measured by the RFX. The
scaling factor is: 0-5 volts represents zero to full
reflected power of the RFX. The unit limits reflected power
at 400 W, therefore 3.33 VDC is the maximum voltage present
on pin 14.
pin 15. LOAD POWER.A
The analog true power signal is a scaled output signal
representing true output power. The scaling factor is: 0-5
volts equals zero to full.
14

pin 16. DC BIAS.A
The analog dc bias signal is a scaled output signal
representing chamber dc bias as measured by the ATX or the
voltage divider/filter network (See the DC Bias Regulation
section on page 18.) When properly calibrated, 0-5 volts
equals 0-1000 volts dc bias.
pin 17. FORWARD POWER.A
The analog forward power signal is a scaled output signal
representing forward power, as measured by the RFX. The
scaling factor is: 0-5 volts represents 0 to 600 W of the
RFX.
pin 18. SIGNAL COMMON
The signal common (ground) is a dedicated common for all user
connector analog input and output signals.
pin 19. POWER COMMON
The power common (ground) is a dedicated common for all user
connector digital and control input and output signals.
pin 20. TUNER OK.D
The digital tuner OK signal is an input from the ATX Tuner
indicating satisfactory tuner operation. The signal is an
active digital high.
15

DIAGNOSTIC CONNECTOR TABLE
(15 Pin, D-Type)
Pin No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Nomenclature
D. C. Current
V - Limit
Primary Current
PWM Program
Level setpoint
Unavailable
P.A. Ed
Exc Power
Signal Common
D. C.
Enable
5V =50V Bus
Fast Loop Program
+5V Reference
16

Dc Bias
"Dc bias" refers to the dc component of the RF power that is
developed between the cathode and the anode of a typical RF
plasma vacuum system. This dc component is blocked from the
RF generator by the capacitors that are used in the
impedance-matching networks.
Thedc potential is a controllable parameter. It is also a
valuable indicator that changes in response to changes in
other process parameters. Some of the parameters that affect
dc bias are molecular densities and ratios of process gases,
cathode/anode surface area ratios, pressure regimes and
stability, and RF power densities. While some of these
parameters are controllable, others are fixed and so must be
worked around.
The amount of dc bias that is developed within a process
system depends upon the system design or the process being
run. Although a systems manufacturer can use modeling or
empirical data to predict the dc bias that should be expected
with a specific system or process, a power supply
manufacturer cannot.
In any case, you can determine dc bias by measuring it
yourself with a high-voltage probe.
DANGER!
Lethal high-voltage and high-current potentials
are present during the measurement of dc bias.
Extreme caution is required to ensure the
safety of yourself and of those working with
you. Carelessness can cause severe burns,
paralysis, or instant death.
Measure dc bias at the RF feedthrough. The farther the probe
is from the feedthrough, the less accurate the measurement.
This is because dc bias decreases with distance from the
feedthrough due to electrical loss. A convenient point for
taking this measurement is inside the impedance- matChing
network, at the output of the series capacitor.
Dc bias can be regulated in two ways, the choice of which
depends upon the process or application. The mutually
exclusive choices result in either maximum range or maximum
resolution.
If you choose maximum range, run the RF generator at maximum
power when you measure dc bias. In the more advanced,
microprocessor- controlled RF generators, a normalization
(calibration) function makes it possible to tailor the
17
~.'

process to the dc bias regulation. with one of these
generators, maximum power will also equate with maximum dc
bias. By normalizing for the maximum dc bias, the process
will have the widest range of available dc biases.
If resolution of the dc bias control is more important, set
your system up for a "typical" process before you measure dc
bias. The new microprocessor- controlled generators will
calibrate the dc bias over a smaller power cross section,
thus providing a higher resolution over a smaller area of
operation.
since what is best for one application will not necessarily
be best for another application, you may calibrate for either
resolution or range, and then later repeat the process for
the other possibility.
Dc BIAS REGULATION
The RFX 600 has the capability to regulate dc bias at the
chamber. If you are using a tuner other than the ATX 600,
you must provide a scaled and filtered dc bias feedback
signal from the chamber to the RFX 600.
To scale the dc bias voltage a 200:1 voltage divider should
be configured using a 2 megohm and a 10 kilohm high voltage
resistor such as the Dale type "HVX3/4".
To filter the scaled dc bias feedback, a dual stage R/C
filter should be configured with 1 kilohm resistors and 1000
picofarad capacitors. See Figure 1 for divider/filter
configuration.
The feedback network is designed to scale 1000 volts dc
chamber bias to a 5 volt dc feedback signal. The front panel
left monitor will display chamber dc bias voltage directly.
The maximum display digits is 1000 volts dc.
18

1
1000
pI 11000 pI
To user pin #2
(DC bias -)
To user pin #1
(de bias +)
1 kQ
2 MQ
10 kQ
Figure 1. DIVIDER/FILTER CONFIGURATION
19

FIRST TIME OPERATION
Unpacking
DO NOT APPLY POWER TO THE UNIT BEFORE FOLLOWING THIS
PROCEDURE:
Unpack and inspect your power supply carefully. Check for
obvious physical damage.
Remove the top cover (6 phillips screws). Inspect the
plexiglass shield for signs of physical damage and if none,
replace cover and proceed to the connection section.
Start-up Procedure
1. Connect output connector to ATX.
2. Connect input power (115 VAC or 240 VAC).
3. Turn on breaker at rear of unit. Fan will turn on.
4. Press power push button on the front panel. Both
displays will turn on, as well as the power LED, RF OFF
LED,
and any control button that is activated.
5. To set output level, select regulation mode (FWDPWR, DC
BIAS, or LOAD PWR). Press SETPOINT push button and hold
while adjusting power level. Observe left display for
desired value. Release button.
CAUTION!
The next step will cause RF to be present at the output
connector. Take appropriate steps to prevent electrical
shock.
6. To enable output, press RF on. The main contactor will
close and the output light will come on. The SETPOINT
light will continue to flash until the output is
delivering its preset level.
20

TROUBLESHOOTING
controlling the unit from the front panel.
1. Front panel display won't light
when the pc:Mer switch is press-
ed. Fan does not a::rne on.
2. 'The lED on the RF ON switch
does not turn on when pressed.
3. '!he lED is lit on the RF ON
p..JSh button, but no OI..ltplt
~er.
a) Make certain the unit is
plug:;ed in.
b) 'Ihe breaker at the rear of
the unit should be pulled
up to the rn position.
a) O1eck to see if the renot:e
ex::ttb:ol p.1sh button has
been pressed. 'The lED on
the p..lSh button should not
be lit.
a) O1eck the RemJte Signal
p..JSh button. 'The lED on
the p..lSh button should not
be lit. If lit p..JSh button
one time.
b) O1eck Maxinn..Irn ~er
setting. If zero, rotate
the Maximum ~er
p::ltentianeter to the
desired pc:Mer level.
c) O1eck CEX ~le: I/O
connector pin 18 should not
be pulled law unless using
external CEX.
d) O1eck pulse input should
not be pliled law.
21