· 100, 200 and 300 amu systems
· Better than 1 amu resolution
· 6 decades of dynamic range
· 5
×
× 10
14
Torr detection limit
· RGA Windows & LabVIEW software
· Field-replaceable electron multiplier
and filament
· RS-232 interface
· RGA100 ... $3750
(U.S. list)
· RGA200 ... $4500
(U.S. list)
· RGA300 ... $6000
(U.S. list)
The 100, 200 and 300 amu residual gas analyzers from SRS
offer exceptional performance and value. These RGAs
provide detailed gas analysis of vacuum systems at about half
the price of competitive models. Each RGA system comes
complete with a quadrupole probe, electronics control unit
(ECU), and a real-time Windows software package that is
used for data acquisition and analysis, as well as probe control.
Rugged Probe Design
The probe consists of an ionizer, quadrupole mass filter, and a
detector. The simple design has a small number of parts which
minimizes outgassing and reduces the chances of introducing
impurities into your vacuum system. The probe assembly is
rugged and mounts onto a standard 2.75" Conflat flange. It is
enclosed within a stainless steel tube, with the exception of the
ionizer which requires just 2.5" of clearance in your vacuum
system
about that of a standard ion gauge. The probe is
designed using self-aligning parts so it can easily be
reassembled after cleaning.
Compact Electronics Control Unit
The densely packed ECU contains all the necessary
electronics for controlling the RGA head. It is powered by
either an external +24 VDC (2.5 A) power supply or an
optional, built-in power module which plugs into an AC
outlet. LED indicators provide instant feedback on the status
of the electron multiplier, filament, electronics system and the
SRS Residual Gas Analyzers
Stanford Research Systems
phone: (408)744-9040
www.thinkSRS.com
www.thinkSRS.com probe. The ECU can easily be removed from the probe for
high-temperature bakeouts.
Unique Filament Design
A long-life, dual thoriated-iridium (ThO
2
/Ir) filament is used
for electron emission. Dual ThO
2
/Ir filaments last much
longer than single filaments, maximizing the time between
filament replacement. Unlike other designs, SRS filaments
can be replaced by the user in a matter of minutes.
Continuous Dynode Electron Multiplier
A Faraday cup detector is standard with all SRS RGAs,
allowing partial pressure measurements from 10
5
Torr
to 5
× 10
11
Torr. For increased sensitivity and faster scan
rates, an optional electron multiplier is offered that detects
partial pressures down to 5
× 10
14
Torr. This state-of-the-art,
multi-channel, continuous-dynode electron multiplier (EM)
offers increased longevity and stability, and can also be
replaced by the user
a first for RGAs.
Useful Features
SRS RGAs have a built-in degassing feature. Using electron
impact desorption, the ion source is thoroughly cleaned,
greatly reducing the ionizers contribution to background noise.
A firmware driven filament protection feature constantly
monitors (675 Hz) for over pressure. If over pressure is
detected, the filament is immediately shut off, preserving its life.
A unique temperature-compensated, logarithmic electrometer
detects ion current from 10
7
to 10
15
amps in a single scan,
with better than 2 % precision. This huge dynamic range
means you can make measurements of small and large gas
concentrations simultaneously.
Complete Programmability
Communication with computers is made via the RS-232
interface. Analog and histogram (bar) scans, leak detection,
and probe parameters are all controlled and monitored through
a high-level command set. This allows easy integration into
existing programs.
RGA Windows Software
The RGA systems are supported with a real-time Windows
software package that runs on PCs. The intuitive graphical
user interface allows measurements to be made quickly and
easily. The program is fully interactive, giving the user
complete control of the graphical display. Screens can be split
for dual-mode operation, scales can be set to linear or log
format, and data can be scaled manually or automatically.
Data is captured and displayed in real time or scheduled for
acquisition at a given time interval for long-term data logging.
Features include user-selectable units (Torr, mbar, Pa and A),
programmable audio and visual alarms, and comprehensive
on-line help.
RGA100/200/300 Residual Gas Analyzers
Dual ThO
2
/Ir filament
Continuous dynode electron multiplier
RGA Windows software
Analog mode
Stanford Research Systems
phone: (408)744-9040
www.thinkSRS.com The software also allows complete RGA head control with
easy mass scale tuning, sensitivity calibration, ionizer setup,
and electron-multiplier gain adjustment. For further analysis,
data files can be saved in ASCII format for easy transfer into
spreadsheets. Graphic images can be saved as META files or
copied to the clipboard for importing directly into other
Windows programs. The software also provides password
protection for locking out head parameters so that casual users
cant alter important settings. A LabVIEW driver is also
available on the SRS website.
An optional stand-alone monitor (PPM100) can be used to
control the RGA without a host computer.
Multi-Head Operation
The software supports multiple head operation when more
than one RGA is needed. Up to eight ECUs can be monitored
from the software.
Performance and Value
The SRS family of RGAs is ideal for applications involving
gas analysis, leak detection, and vacuum processing. We offer
100, 200 and 300 amu systems with supporting Windows
software, and options that include an electron multiplier and a
built-in power module for AC line operation. The RGA
Windows software is available on the web at
www.thinkSRS.com
.
RGA100/200/300 Residual Gas Analyzers
RGA rear panel
(without AC power module)
RGA rear panel
(with AC power module)
RGA dimensional drawing (inches)
Stanford Research Systems
phone: (408)744-9040
www.thinkSRS.com Pressure vs. time presents a strip chart of
partial pressures for selected masses and
provides a complete time history of your
data. Complete scrolling and zoom control
is available even while data is being
acquired. This mode is most often used for
monitoring process trends.
Leak detection mode monitors a particular
mass number (not just helium) over time,
and combines many features of the
previous modes. A vertical bar graph
provides a visual reference for viewing
changes in intensity from a distance. A
programmable audible tone, large numeric
read-out, and visual alarm are also provided.
Annunciator mode
is provided for
conveniently monitoring up to 10 masses.
If a particular mass has tripped its preset
alarm, the large box will turn red
indicating a problem. An audible alarm
will also be present until the mass falls
back within its preset limits. This mode is
most often used for Go/No-Go testing.
Analog mode provides a line graph
representation of the acquired mass
spectrum (partial pressure vs. mass
number). Span, resolution and noise floor
can each be set. Scans can be single-shot,
timed or taken continuously.
Histogram mode displays a bar graph of
partial pressure vs. mass, allowing the
spectrum to easily be interpreted. This
mode is often used for quick and easy
vacuum analysis. The screen can be split
for viewing two modes of operation
simultaneously.
Table mode provides a readout of mass,
scaling factor, and true partial pressure.
The display shows the peak heights and
alarm status of up to 10 masses. The
electron multiplier can be independently
set on or off for each mass. This allows the
user to view minor species even in the
presence of high total pressure.
Library mode contains a comprehensive
list of gases that can be used to compare
against the current spectrum. A search
mode allows you to select up to 12 masses
and identify and display (numerically and
graphically) the intensity of all gases that
contain these masses.
Analysis utility provides an approximation
of the composition of gases being
monitored by the RGA. Since more than
one gas can contribute to a particular
amus partial pressure, the analysis mode
is extremely useful in determining the
make-up of complex gases. Up to 12 common
gases can be selected for the analysis.
Multi-head operation is available when
when more than one RGA is needed for
analysis. Up to eight heads can be
monitored simultaneously from the software.
RGA100/200/300 Software
Stanford Research Systems
phone: (408)744-9040
www.thinkSRS.com RGA100/200/300 Specifications
ECU dimensions
3.1"
× 4.1" × 9.1" (WHD). Easily
separated from the probe for bakeout.
LED indicators
Power ON/OFF, filament ON/OFF,
degas ON/OFF, electron multiplier
ON/OFF, RS-232 Busy, Error,
Overpressure, Burnt Filament
Warm-up time
Mass stability ±0.1 amu after 30
minutes
Computer interface
RS-232C, 28,800 baud with high-
level command set
Software Windows
based
application
Power requirement
24 VDC @ 2.5 amps, male DB9
connector, optional built-in power
module for AC line operation
Weight
6 lbs.
Warranty
One year parts and labor on defects
in materials and workmanship
Ordering Information
RGA100
100 amu RGA w/ RS-232
$3750
RGA200
200 amu RGA w/ RS-232
$4500
RGA300
300 amu RGA w/ RS-232
$6000
Option 01
Electron multiplier
$1500
Option 02
AC power module
$250
Option 03
Ion counting output
$250
O100HJR
200 °C heater jacket
$395
O100MAX
Max. insertion nipple (4.5" CF)
$400
O100EM
Replacement electron multiplier
$1000
O100RF
Repla