QMS SC-100 Manual de usuario

User’s Manual QMS 100 Series Gas Analyzer 1290-D Reamwood Avenue Sunnyvale, CA 94089 U.S.A. Phone: (408) 744-9040, Fax: (408) 744-9049 Email

x SRS QMS Gas Analyzer Calibration Log SRS serial number ___________ In the table below are the results of the factory calibration of the inle

1-10 Capillary DesignSRS QMS Gas AnalyzerCapillary DesignThe inlet uses a bypass configuration that results in a fast response time. A large flow

Capillary Design 1-11Technical ReferenceThe chromatography industry uses a large variety of capillaries, from which we can select capillaries fo

1-12 Capillary DesignSRS QMS Gas AnalyzerMaterials and FittingsUsers will find vendors of gas chromatography supplies a good source for capillaries

Capillary Design 1-13Technical ReferenceExtensionsAs discussed in the previous section, the capillary can be designed to any length necessary by

SRS QMS Gas Analyzer Technical ReferenceChapter 2. Quadrupole SpectrometerThis chapter describes the design and principles of operation of the compone

2-2 IntroductionSRS QMS Gas AnalyzerIntroductionThe SRS RGA is a mass spectrometer consisting of a quadrupole probe, and an Electronics ControlUnit

ECU 2-3Technical ReferenceECUIndependently from the gas handling susbsystem, the ECU completely controls the operation of thespectrometer, handles i

2-4 ECUSRS QMS Gas Analyzerchanges in the calibration parameters by inexperienced operators. Peak tuning is completely disabledwhen the jumper is c

Electrometer 2-5Technical ReferenceElectrometerDetection limit vs. scan rateA unique, temperature-compensated, logarithmic picoammeter built into th

2-6 ElectrometerSRS QMS Gas AnalyzerWhen using the RGA Windows program to operate the RGA, the Scan Speed parameter settingavailable in the Scan Pa

SRS QMS Gas AnalyzerChapter 1. Introduction & OperationIn This ChapterIntroduction ...

Mass Filter Power Supply 2-7Technical ReferenceMass Filter Power SupplyAll the necessary electronics required to power up the quadrupole mass filter

2-8 IonizerSRS QMS Gas AnalyzerIonizerPositive ions are produced in the ionizer by bombarding gas molecules with electrons derived from aheated fil

Ionizer 2-9Technical ReferencePrinciple of operationThe principle of operation of the ionizer is similar to the Bayard-Alpert gauge, except there is

2-10 IonizerSRS QMS Gas AnalyzerParameter SettingsThe parameters that affect the ionization efficiency of the ionizer are: electron energy, ion ene

Ionizer 2-11Technical ReferenceIon energy also determines the time spent by the ions in the fringing fields at the entrance and exit pointsof the fi

2-12 Quadrupole mass filterSRS QMS Gas AnalyzerQuadrupole mass filterPositive ions are transferred from the ionizer into the quadrupole where they

Quadrupole mass filter 2-13Technical Referencepotential terms. The radius of the circle inscribed by the rods is 0.109”. The frequency of operation

2-14 Quadrupole mass filterSRS QMS Gas Analyzercompared to other types of analyzers. The upper limit of useful operation is determined by the colli

Quadrupole mass filter 2-15Technical ReferenceThe mass range is the range of masses defined by the lightest and the heaviest singly charged ionswhic

2-16 Quadrupole mass filterSRS QMS Gas AnalyzerIt is well established that the resolution attainable by a quadrupole is limited by the number of cy

1–2 IntroductionSRS QMS Gas AnalyzerIntroductionThe QMS 100 series instruments are modern massspectrometers designed for the analysis of light gase

Ion Detector 2-17Technical ReferenceIon DetectorPositive ions that successfully pass through the quadrupole are focused towards the detector by an e

2-18 Ion DetectorSRS QMS Gas Analyzermounting the CDEM cone very close to the top of the FC. The clip anchors the CDEM glass tube tothe side of the

Ion Detector 2-19Technical Referenceof the electron multiplier currents is reversed before the current value is sent out over RS232 so that thecompu

2-20 Ion DetectorSRS QMS Gas Analyzeralong the channel walls replenishing their charge as secondary electrons are emitted. Channel electronmultipli

Ion Detector 2-21Technical Referenceapplications. However, in order to achieve maximum useful lifetime and optimum performance, it is veryimportant

SRS QMS Gas Analyzer Technical ReferenceChapter 3. Programming the RGAThis chapter describes how to program the RGA ECU from a host computer using the

3-2 IntroductionSRS QMS Gas AnalyzerMIparam, param: 1 - M_MAX, *, ? ...

Introduction 3-3Technical ReferenceIntroductionThe RGA comes standard with an RS232 communications port. A host computer interfaced to theRGA can ea

3-4 The RGA COM UtilitySRS QMS Gas AnalyzerThe RGA COM UtilityThe RGA Com Utility is a simple Windows™ OS communication program that allows you toc

Command Syntax 3-5Technical ReferenceCommand SyntaxThe RGA commands are ASCII character strings consisting of a two letter (case insensitive) comman

Introduction 1–3SRS QMS Gas Analyzerneeds of most users. For users with specialized needs, the QMS can be controlled from user programs.The Technica

3-6 Command SyntaxSRS QMS Gas AnalyzerID? RGA Identification Query.MI1 Set initial scan mass to 1 amu.MF100 Set final scan mass to 100 amu.FL1.0 Tu

Communication Errors 3-7Technical ReferenceCommunication ErrorsCommunication errors are signaled to the user flashing the Error LED a few times, set

3-8 Communication ErrorsSRS QMS Gas AnalyzerJumper Protection ViolationSome calibration related commands are subject to jumper protection. Jumper J

Programming the RGA ECU 3-9Technical ReferenceProgramming the RGA ECUThis section describes the basic programming steps needed to configure, operate

3-10 Programming the RGA ECUSRS QMS Gas Analyzer-Check the quality of the serial connection to the host computer.-Check the user’s communication so

Programming the RGA ECU 3-11Technical ReferenceProgramming the DetectorPositive ions that successfully pass through the quadrupole filter are focuse

3-12 Programming the RGA ECUSRS QMS Gas AnalyzerPlease consult the RGA Command Set section for details on the CA command.Detector Programming examp

Programming the RGA ECU 3-13Technical Reference• Follow all recommended procedures for the operation of the CDEM. Consult the RGAMaintenance chapte

3-14 Programming the RGA ECUSRS QMS Gas AnalyzerMF150 Final mass = 150 amu.NF7 Fastest scan rate selected.SA10 Steps/amu = 10.AP? Analog Points que

Programming the RGA ECU 3-15Technical ReferenceHistogram scans are triggered with the HS command. The scan parameter can be set for single, multiple

1–4 What’s Inside ?SRS QMS Gas AnalyzerThe system exhausts to the rear panel. All of the gas drawn into the inlet is exhausted through this port.Th

3-16 Programming the RGA ECUSRS QMS Gas Analyzer• Any command sent to the RGA during scanning will immediately halt the scanning actionand clear t

Programming the RGA ECU 3-17Technical Referencescanning procedure, referred to as Peak-Locking, is designed to measure peak currentsfor individual m

3-18 Programming the RGA ECUSRS QMS Gas Analyzer• The output of a D/A converter can be linearly related to the readings obtained at acertain mass.

Programming the RGA ECU 3-19Technical Referencegauge readings. Expect to see deviations between the two gauges as thecomposition of a residual gas c

3-20 Programming the RGA ECUSRS QMS Gas AnalyzerMG: CDEM gain at the HV setting stored in MV. See MG command.See the Parameter Storage commands lis

Programming the RGA ECU 3-21Technical ReferenceThe net result is very stable RF/DC levels that are highly insensitive to the operating conditions of

3-22 Programming the RGA ECUSRS QMS Gas Analyzer3. The Burnt and Leak LED’s indicate specific filament problems and are turned on, inaddition to t

Programming the RGA ECU 3-23Technical ReferenceThe Error LED is immediately turned on if any one of the bits 1-7 of STATUS is set. Bit 0 of STATUSre

3-24 Programming the RGA ECUSRS QMS Gas AnalyzerThe RGA is turned on and, after all the internal checks are performed, the green Power LED and theE

RGA Command Set 3-25Technical ReferenceRGA Command SetThis section lists and describes the commands of the RGA’s Command Set. The commands aresepara

What’s Inside ? 1–5SRS QMS Gas Analyzera length of 0.9 m. Most of the capillary flow does not travel to the RGA, but is bypassed directly to thedia

3-26 RGA Command SetSRS QMS Gas AnalyzerInitialization CommandsID?Description: Identification query.Echo: ID string.Use to identify the RGA ECU co

RGA Command Set 3-27Technical ReferenceInitialize the RGA to a known state.Three different levels of initialization are available.Command excecution

3-28 RGA Command SetSRS QMS Gas AnalyzerIonizer Control CommandsDGparam, param: 0 - 20,*Description: Ionizer Degas commandEcho: STATUS error byt

RGA Command Set 3-29Technical Reference8. At the end of the time specified by the parameter (and if no problems were encountered) theDegas_LED is tu

3-30 RGA Command SetSRS QMS Gas AnalyzerCommand excecution times vary depending on the pre-existing ionizer conditions. The end of thecommand excec

RGA Command Set 3-31Technical Reference• The repeller grid and the focus plate are only biased while the filament isemitting electrons.• In order

3-32 RGA Command SetSRS QMS Gas AnalyzerSince the axis of the quadrupole mass filter is at ground, the ion energy (in eV) is equal to the anode gri

RGA Command Set 3-33Technical ReferenceCommand excecution times vary depending on the pre-existing ionizer conditions. The end of thecommand excecut

3-34 RGA Command SetSRS QMS Gas AnalyzerDetection Control CommandsCADescription: Calibrate All.Echo: STATUS Error Byte.Readjust the zero of the io

RGA Command Set 3-35Technical ReferenceNotes:• This mass axis correction procedure can also be triggered at any time, byitself, using the RS and RI

1–6 What’s Inside ?SRS QMS Gas AnalyzerMass SpectrometerA residual gas analyzer (RGA) is mass spectrometer of small physical dimensions whose funct

3-36 RGA Command SetSRS QMS Gas Analyzer• All offset correction factors previously stored in memory are cleared after acomplete calibration of the

RGA Command Set 3-37Technical Reference• It is good practice to readjust the Zero of the ion detector every time the typeof detector (FC or CDEM) i

3-38 RGA Command SetSRS QMS Gas AnalyzerError Checking:The CDEM option (Opt01) must be available in the RGA ECU receiving the command or a bad-comm

RGA Command Set 3-39Technical ReferenceA decrease in the Noise-Floor setting results in cleaner baselines and lower detection limits during scansand

3-40 RGA Command SetSRS QMS Gas AnalyzerScan and Measurement CommandsAP?Description: Analog Scan Points Query.Echo: Query Response.Query the total

RGA Command Set 3-41Technical ReferenceImportant: The query response does not include the extra current (4 bytes) corresponding to the totalpressure

3-42 RGA Command SetSRS QMS Gas Analyzer• The detector’s zero and the internal scan parameters are checked andcorrected at the beginning of each s

RGA Command Set 3-43Technical Referencecomputer over RS232. As a result of the high acquisition rate of the RGAthere might be a delay between the ti

3-44 RGA Command SetSRS QMS Gas AnalyzerThe mass value set by MF must always be greater than or equal to the initial mass setting of MI or else apa

RGA Command Set 3-45Technical ReferenceThe type of detector and noise-floor settings to be used by the measurement must be selected in advancewith t

Operation 1–7SRS QMS Gas Analyzer• Histogram scanning• Single mass measurementRGA Windows provides fast access to all the RGA functions without th

3-46 RGA Command SetSRS QMS Gas AnalyzerThe upper mass limit depends on the RGA model number: M_MAX=100 for RGA100, 200 for RGA200and 300 for the R

RGA Command Set 3-47Technical ReferenceParameters:SAparam, param: 10-25: The parameter specifies the number of steps-per-amu desired during analog

3-48 RGA Command SetSRS QMS Gas Analyzer• A Total Pressure measurement is performed at the end of each scanand transmitted out to the host compute

RGA Command Set 3-49Technical Referencereceived to the time it actually starts. Using the SC1 command and waitinguntil the whole scan data stream i

3-50 RGA Command SetSRS QMS Gas Analyzerdifferent from that of the Bayard Alpert gauge readings. Expect to see deviations between the twogauges as

RGA Command Set 3-51Technical ReferenceParameter Storage CommandsMGparam, param: 0.0000 - 2000.0000,?Description: Electron Multiplier Gain Storage

3-52 RGA Command SetSRS QMS Gas AnalyzerImportant: The voltage value is not used internally by the RGA to set the bias voltage of the ElectronMulti

RGA Command Set 3-53Technical ReferenceSTparam, param:0.0000 - 100.0000, ?Description: Total Pressure Sensitivity Factor storage.Echo: Query Respo

3-54 RGA Command SetSRS QMS Gas AnalyzerMass Filter Control CommandsMLparam, param: 0.0000 - M_MAXDescription: Mass LockEcho: noneActivate the qu

RGA Command Set 3-55Technical ReferenceError Reporting CommandsEC?Description: RS232_ERR Byte QueryEcho: RS232_ERR Byte.Query the value of the RS23

1–8 OperationSRS QMS Gas AnalyzerFront Panel OperationThe two pumps and two valves are operated with the four switches on the small panel (see Figu

3-56 RGA Command SetSRS QMS Gas AnalyzerED?Error checking:The only acceptable parameter is a question mark.The absence of a parameter (i. e. ED) is

RGA Command Set 3-57Technical ReferenceThis query command can be used to determine whether the CDEM option is installed in the RGA unitbeing program

3-58 RGA Command SetSRS QMS Gas Analyzerresults). The QMF_ERR byte value is returned to the computer in ASCII format and with a <LF><CR>

RGA Command Set 3-59Technical ReferenceError checking:The only acceptable parameter is a question mark.The absence of a parameter (i. e. ER) is trea

3-60 RGA Command SetSRS QMS Gas AnalyzerTuning CommandsCE?Description: Calibration Enable Query.Echo: JP100 setting.Query the Calibration Enable/D

RGA Command Set 3-61Technical Referencenon-volatile memory of the RGA, to calculate the 8 bit settings of the DAC according to the linearequation:DA

3-62 RGA Command SetSRS QMS Gas AnalyzerProgram the value of DS during the Peak Width Tuning Procedure. The parameter (one of four peaktuning param

RGA Command Set 3-63Technical ReferenceRIparam, param: -86.0000 - +86.0000, *, ?, noneDescription: RF_Driver output @ 0 amu (Peak Position Tuning

3-64 RGA Command SetSRS QMS Gas AnalyzerError checking:The absence of a parameter (i. e. RI) is treated as an error in the parameter.This parameter

RGA Command Set 3-65Technical ReferenceRS: Uses the current parameter value to recalculate the internal scan parameters used to step the RFduring s

Operation 1–9SRS QMS Gas AnalyzerController State Diagram0134-1OffVentRou gh Pum pBypass FlowSample Flow21T u rbo pum p is not at s peedP res s u

3-66 Error Byte DefinitionsSRS QMS Gas AnalyzerError Byte DefinitionsThe Error Bytes described in this section store the results of the firmware-dr

Error Byte Definitions 3-67Technical ReferencePS_ERR Error Byte: 24V P/S Error Byte.Bit Description Error Code7 External 24V P/S error: Voltage >

3-68 Error Byte DefinitionsSRS QMS Gas AnalyzerQMF_ERR Error Byte: Quadrupole Mass Filter RF P/S Error Byte.Bit Description Error Code7 RF_CT excee

Error Byte Definitions 3-69Technical ReferenceFIL_ERR Error Byte: Filament Error Byte.Bit Description Error Code7 No filament detected. FL76 Unable

SRS QMS Gas Analyzer Technical ReferenceChapter 4. Trouble ShootingIn This ChapterSystem Problems ...

4-2 System ProblemsSRS QMS Gas AnalyzerSystem ProblemsDiaphragm Pump Does Not StartIf the light next to the diaphragm pump switch on the front panel

System Problems 4-3Technical ReferenceLoud Noises While Shutting DownIt is common to hear loud noises while the turbo pump is coasting to a stop.

4-4 Internal Error Detection in the SRS RGASRS QMS Gas AnalyzerInternal Error Detection in the SRS RGASeveral firmware-driven checks automatically t

Internal Error Detection in the SRS RGA 4-5Technical Reference• The query command that can be used to trigger the check (see Error Reporting Comm

4-6 Internal Error Detection in the SRS RGASRS QMS Gas Analyzerchecked at any time with the query command: ED?.Several tests are performed during th

Certification Stanford Research Systems certifies that this product met its published specifications at the time of shipment. Warranty This

1–10 OperationSRS QMS Gas AnalyzerThe microcontroller is inactive for about 5 seconds after main power is turned on. The user cannot turnon any of

Internal Error Detection in the SRS RGA 4-7Technical ReferenceFilament’s Background Protection modeSTATUS Bit affected: 1Error Byte affected: FIL_E

4-8 Windows Software Error CodesSRS QMS Gas AnalyzerWindows Software Error CodesA unique Error Code has been assigned to each one of the fault condi

Windows Software Error Codes 4-9Technical ReferenceTroubleshooting: Contact SRS.DET5Type of Error: ElectrometerError Message: Electrometer Error: D

4-10 Windows Software Error CodesSRS QMS Gas AnalyzerEM7Type of Error: Electron MultiplierError Message: Electron Multiplier Error: No Electron Mult

Windows Software Error Codes 4-11Technical Reference If a short is detected, remove the probe from the vacuum system , inspect theionizer and fix a

4-12 Windows Software Error CodesSRS QMS Gas AnalyzerTroubleshooting: Check the voltage output of the external power supply with a voltmeter.Adjust

Windows Software Error Codes 4-13Technical ReferenceError Cause: The circuit that drives the primary of the RF Transformer is delivering anunusuall

4-14 Windows Software Error CodesSRS QMS Gas Analyzercontinuously for a long time.Note: During the warm-up period, RGA Windows users should see that

SRS QMS Gas Analyzer Technical ReferenceChapter 5. ServiceThe QMS contains no user serviceable parts. The service information in this chapter is int

5-2 Warnings!SRS QMS Gas AnalyzerWarnings!• The service information in this chapter is for the use of Qualified Service Personnel.To avoid shock,

Operation 1–11SRS QMS Gas Analyzerestablished, the sample valve will open, and measurements can be made. When the capillary flow valveis first open

Component Notes 5-3Technical ReferenceComponent NotesGas Handling ComponentsThe QMS system is designed to require low maintenance. A regular maint

5-4 Component NotesSRS QMS Gas Analyzerdoubled to 2 mbar. The turbo pump can easily tolerate exhaust pressures up to 5 mbar, so theperformance of t

Component Notes 5-5Technical ReferenceCDEM Handling and CareContinuous Dynode Electron Multipliers (CDEM) have a history of high performance and de

5-6 Component NotesSRS QMS Gas Analyzerliquid nitrogen traps with diffusion pumps (particularly for silicone oil based pumps) , and molecularsieves

Accessing Internal Components 5-7Technical ReferenceAccessing Internal ComponentsThe first step to all of the service procedures in the cleaning or

5-8 Accessing Internal ComponentsSRS QMS Gas AnalyzerInternal ViewMap of Internal Components

Accessing Internal Components 5-9Technical ReferenceRemoving the RGA ECUThe RGA ECU is supported between the front panel and the probe body. After

5-10 Accessing Internal ComponentsSRS QMS Gas Analyzer• Work in a clean dust-free area. Avoid dust, lint and any kind of particulate matter.• We

General Checks 5-11Technical ReferenceGeneral ChecksLeak TestingThe seals in the system will have a long life. The metal seals will last indefinite

5-12 General ChecksSRS QMS Gas Analyzerto install a second gauge in the inlet fitting of the QMS. The two gauges are then compared to see if thein

1–12 OperationSRS QMS Gas AnalyzerIf the diaphragm pump is inadvertently stored under vacuum for extended periods, the internal pressureswill reach

Cleaning 5-13Technical ReferenceCleaningThe most general method of cleaning the QMS is to use the vacuum pumps to remove contaminants.The inlet sec

5-14 CleaningSRS QMS Gas Analyzer2. Wrap a heating tape or heating jacket around the vacuum chamber. Make sure the entire probe,including flanges,

Cleaning 5-15Technical ReferenceWarning:The fumes from isopropyl alcohol can be dangerous to health if inhaled and are highlyflammable. Work in wel

5-16 CleaningSRS QMS Gas Analyzer• The exact alignment of the rods in the quadrupole is essential to the optimumperformance of the RGA.• Do not s

Cleaning 5-17Technical Reference Figure 1 Probe Removal for Quadrupole Filter Cleaning6. Carry the probe to a clean, dust free area immediately.

5-18 CleaningSRS QMS Gas Analyzergrit down to 12000 until the metal surface has a fine polished appearance. Warning: Do notremove excessive materia

Cleaning 5-19Technical Reference16. Visually inspect the probe to make sure all the parts are in place and correctly aligned. Use anohmmeter to mak

5-20 Component ReplacementSRS QMS Gas AnalyzerComponent ReplacementIonizer ReplacementAs the RGA is used, deposits form on the ionizer parts and th

Component Replacement 5-21Technical Reference Figure 2 Probe Removal for Ionizer Replacement6. Carry the probe to a clean, dust free area immedia

5-22 Component ReplacementSRS QMS Gas Analyzer16. Attach the new repeller to the longer filament rod using a fresh screw. Align the cage and tighte

Operation 1–13SRS QMS Gas AnalyzerMicrocontroller Error ChecksThe microcontroller is programmed to prevent the system from restarting after a power

Component Replacement 5-23Technical ReferenceFilament ReplacementThe filament eventually wears out and needs to be replaced. The replacement proced

5-24 Component ReplacementSRS QMS Gas Analyzer Figure 3 Probe Removal for Filament Replacement6. Immediately carry the probe to a clean, dust-fre

Component Replacement 5-25Technical Referencerepeller and anode grid and need to be corrected. Use gentle pressure on the filament wire tobend it

5-26 Component ReplacementSRS QMS Gas Analyzer2. Set up in advance a clean dust-free working area where to carry out this procedure.3. Turn off t

Component Replacement 5-27Technical Referencecontacts. A plate (CDEM Anode) mounted at the exit of the CDEM collects the secondaryelectrons. The wh

5-28 Replacement PartsSRS QMS Gas AnalyzerReplacement PartsSome of the parts discussed in the previous sections are widely available. For users wh

Factory Service 5-29Technical ReferenceFactory ServiceThe procedures described in this chapter are designed to guide the user through the various s

SRS QMS Gas Analyzer Technical ReferenceAppendix A. System ElectronicsIn This ChapterDescription of Schematics ...

A-2 Description of SchematicsSRS QMS Gas AnalyzerDescription of SchematicsControl of the system originates from the microcontroller board mounted t

Description of Schematics A-3Technical ReferenceSchematic: MCA_C2The relay and two solenoid valves have 24 VDC coils. The relay draws very little

1–14 OperationSRS QMS Gas AnalyzerOperating Modes of the SpectrometerThe RGA is a mass spectrometer that analyzes residual gases by ionizing some o

A-4 Parts ListSRS QMS Gas AnalyzerParts ListMicrocontroller Board and Chassis Assembly Parts ListREF. SRS part# VALUE DESCRIPTIONC 1 5-00011-501 27

Parts List A-5Technical ReferenceJ 7 1-00250-116 2 PIN, WHITE Header, Amp, MTA-156J 8 1-00037-130 16 PIN DIL Connector, MalePC1 7-00748-701 QMS CON

A-6 Parts ListSRS QMS Gas AnalyzerU 11 3-00546-340 HDSP-4830 Integrated Circuit (Thru-hole Pkg)U 12 3-00546-340 HDSP-4830 Integrated Circuit (Thru-

Parts List A-7Technical ReferenceZ 0 1-00316-113 8 PIN, 18AWG/OR Connector, Amp, MTA-156Z 0 1-00317-179 2 PIN PLUG Connector Housing, ReceptacleZ 0

Appendix B RGA Circuit DescriptionThis chapter describes the electronics circuits located inside the Electronics Control Unit ofthe RGA. There are n

B-2 Overview of the RGASRS QMS Gas AnalyzerSchematic name: QMSE_V1...

Overview of the RGA B-3Technical Reference Overview of the RGAThe SRS RGA is a mass spectrometer consisting of a quadrupole probe, and an Electron

B-4 Circuit DescriptionSRS QMS Gas Analyzer Circuit Description General DescriptionThe specifications and features of the many circuits that drive t

Circuit Description B-5Technical Referencemultiplier may be used. The electron multiplier needs to be biased with as much as -2500VDC toprovide ga

B-6 Description of SchematicsSRS QMS Gas Analyzer Description of Schematics Schematic name: QMSE_T1 MicroprocessorAn MC68HC11E9 microcontroller is

Operation 1–15SRS QMS Gas AnalyzerRGA Windows uses the two modes to generate the data for the Analog and Histogram Scan Modes.Analog scanning is the

Description of Schematics B-7Technical ReferencePD0 RXD RS232 data received from host computer.PD1 TXD RS232 data transmitted to host computer.PD2

B-8 Description of SchematicsSRS QMS Gas AnalyzerQ2 CAL_2 MSB of current detector calibration attenuatormultiplexer.Q3 MPX_0 LSB of 16-bit A/D convert

Description of Schematics B-9Technical Reference RS232 InterfaceThe microcontroller communicates with a host computer via the RS232 interface. The

B-10 Description of SchematicsSRS QMS Gas Analyzer-IRQ, the CPU sets CS_VETO high (which sets -CS_ADC16 high) and sets R/-C high to allow thedata to b

Description of Schematics B-11Technical Reference RF Amplitude DetectionThe amplitude of the RF is detected by a full-wave charge pump detector. I

B-12 Description of SchematicsSRS QMS Gas AnalyzerThe 18-bit DAC output is also used to set the DC potentials applied to the mass filter. RF_SET ismul

Description of Schematics B-13Technical Referencewith the correct amplitude and phase into the primary drive inductor, T401, to cancel the chargein

B-14 Description of SchematicsSRS QMS Gas AnalyzerDE_GAS bit) to the voltage seen on the 100Ω emission current shunt resistor, R522. (The currentsense

Description of Schematics B-15Technical ReferenceFor a high power de-gas, a DPDT relay is used to by-pass the bias regulators, connecting the grid

B-16 Description of SchematicsSRS QMS Gas Analyzerlowest current which may be detected. Extreme care is required to achieve low drift and low noisecur

1–16 Mass Spectrometry BasicsSRS QMS Gas AnalyzerMass Spectrometry BasicsThe RGA can perform both qualitative and quantitative analysis of the gase

Description of Schematics B-17Technical Reference Schematic name: QMSE_V2 Electron Multiplier High Voltage Power SupplyThe electron multiplier op

B-18 Parts ListsSRS QMS Gas Analyzer Parts ListsTop Board Parts ListREF. SRS part# VALUE DESCRIPTIONC 100 5-00023-529 .1U Cap, Monolythic Ceramic, 50

Parts Lists B-19Technical ReferenceC 303 5-00239-562 680P Cap., NPO Monolitic Ceramic, 50v, 5% RaC 304 5-00233-532 22P Capacitor, Ceramic Disc, 50

B-20 Parts ListsSRS QMS Gas AnalyzerQ 104 3-00021-325 2N3904 Transistor, TO-92 PackageQ 105 3-00021-325 2N3904 Transistor, TO-92 PackageQ 106 3-00021-

Parts Lists B-21Technical ReferenceR 210 4-00192-407 49.9K Resistor, Metal Film, 1/8W, 1%, 50PPMR 211 4-00142-407 100K Resistor, Metal Film, 1/8W,

B-22 Parts ListsSRS QMS Gas AnalyzerR 316 4-00021-401 1.0K Resistor, Carbon Film, 1/4W, 5%R 317 4-00188-407 4.99K Resistor, Metal Film, 1/8W, 1%, 50PP

Parts Lists B-23Technical ReferenceU 307 3-00633-340 MAX528CPP Integrated Circuit (Thru-hole Pkg)Z 0 0-00042-010 4-40 HEX Nut, HexZ 0 0-00241-021 4

B-24 Parts ListsSRS QMS Gas AnalyzerC 505 5-00329-526 120U Capacitor, Electrolytic, 35V, 20%, RadC 506 5-00264-513 .0015U Capacitor, Mylar/Poly, 50V,

Parts Lists B-25Technical ReferenceD 503 3-00004-301 1N4148 DiodeD 504 3-00004-301 1N4148 DiodeD 505 3-00203-301 1N5711 DiodeD 506 3-00004-301 1N41

B-26 Parts ListsSRS QMS Gas AnalyzerPC1 7-00670-701 RGA BOTTOM Printed Circuit BoardQ 400 3-00022-325 2N3906 Transistor, TO-92 PackageQ 404 3-00627-32

Mass Spectrometry Basics 1–17SRS QMS Gas AnalyzerNotes on Fragmentation Patterns: The electron impact type of ionizer used in modern RGA’s almostalw

Parts Lists B-27Technical ReferenceR 424 4-00405-407 2.49M Resistor, Metal Film, 1/8W, 1%, 50PPMR 425 4-00034-401 10K Resistor, Carbon Film, 1/4W,

B-28 Parts ListsSRS QMS Gas AnalyzerR 517 4-00141-407 100 Resistor, Metal Film, 1/8W, 1%, 50PPMR 518 4-00031-401 100 Resistor, Carbon Film, 1/4W, 5%R

Parts Lists B-29Technical ReferenceR 617 4-00800-401 1 Resistor, Carbon Film, 1/4W, 5%R 618 4-00058-401 220K Resistor, Carbon Film, 1/4W, 5%RL500 3

B-30 Parts ListsSRS QMS Gas AnalyzerVertical Board Parts ListREF. SRS part# VALUE DESCRIPTIONC 700 5-00023-529 .1U Cap, Monolythic Ceramic, 50V, 20%,

Parts Lists B-31Technical ReferenceD 810 3-00626-301 MUR1100E DiodeD 811 3-00626-301 MUR1100E DiodeD 812 3-00004-301 1N4148 DiodeJ 701 1-00268-120

B-32 Parts ListsSRS QMS Gas AnalyzerR 705 4-00193-407 499 Resistor, Metal Film, 1/8W, 1%, 50PPMR 706 4-00032-401 100K Resistor, Carbon Film, 1/4W, 5%R

Parts Lists B-33Technical ReferenceZ 0 0-00308-021 4-40X7/8PP Screw, Panhead PhillipsZ 0 0-00316-003 PLTFM-28 InsulatorsZ 0 0-00317-000 40MM 24V Ha

Technical ReferenceAppendix C. Drawings & SchematicsThis appendix contains foldout drawings & schematics refered to in previous chapters.Sys

Stanford Research Systems, 1290 D Reamwood Ave., Sunnyvale, CA 94089, Ph. (408) 744-9040, FX. 744-9049Declaration of Contamination of Vacuum Equipment

1–18 Mass Spectrometry BasicsSRS QMS Gas AnalyzerSg = RGA’s partial pressure sensitivity factor for gas g, in amp/Torr (see Partial Pressure Sensit

Mass Spectrometry Basics 1–19SRS QMS Gas AnalyzerThe sensitivity of the RGA varies with different gases, changes with time due to aging of the head,

iii SRS QMS Gas Analyzer Table of Contents Safety ...

1–20 Mass Spectrometry BasicsSRS QMS Gas Analyzerbuilt into the program, can adjust the CDEM voltage for any gain between 10 and 106. Consult theRG

SRS QMS Gas Analyzer Chapter 2. Windows Software The QMS system contains a mass spectrometer that belongs to a class of spectrometers commonly r

2-2 Overview SRS QMS Gas Analyzer Running in Split Display Mode...

Overview 2-3 SRS QMS Gas Analyzer Overview Program Structure The RGA program is a fully interactive Windows program capable of managing sev

2-4 System Requirements SRS QMS Gas Analyzer RGA ASCII Data files (.txt) The RGA program can save the last scan data in an ASCII format that is

Getting Started 2-5 SRS QMS Gas Analyzer Starting the RGA Software To start the RGA software simply double-click on the RGA icon in the &qu

2-6 Features and Operation SRS QMS Gas Analyzer The recommended shut-down procedure is: 1. Stop the scan if there is one in progress using the

Features and Operation 2-7 SRS QMS Gas Analyzer Analog (Mode Menu) Analog mode is the spectrum analysis mode common to all Residual Gas Ana

2-8 Features and Operation SRS QMS Gas Analyzer Spec Scan Parameters menu button on the toolbar Table entries can be configured independently

Features and Operation 2-9 SRS QMS Gas Analyzer parameters, alarm parameters, and graph trace colors. The data acquisition method for the

iv SRS QMS Gas Analyzer Safety WARNING Hazardous voltages, capable of causing injury or death, are present in this instrument. Use extreme ca

2-10 Features and Operation SRS QMS Gas Analyzer The Annunciator channels can be independently configured. Some channels can use the Channel E

Features and Operation 2-11 SRS QMS Gas Analyzer 2. Establish a connection between the RGA program and the Head (Connector List Setup in t

2-12 Features and Operation SRS QMS Gas Analyzer example, if the background mode in Analog mode is changed to yellow, the background mode of al

RGA Head and Scan Parameters 2-13 SRS QMS Gas Analyzer Background Data This mode is helpful in providing the user with a clean baseline aft

2-14 RGA Head and Scan Parameters SRS QMS Gas Analyzer Note: Changing scan parameters will result in loss of all displayed data on the screen.

Display Modes 2-15 SRS QMS Gas Analyzer Scanning With The Filament Off The software can run experiments with the filament off. This is usef

2-16 Display Modes SRS QMS Gas Analyzer Changing Display Modes A display mode presents the user with a specific way to analyze the RGA data acq

General Utilities 2-17 SRS QMS Gas Analyzer To Enable the Background mode make sure the graph has valid data and the RGA head is connected.

2-18 General Utilities SRS QMS Gas Analyzer In PvsT mode, the cursor values are displayed in the legend box. If the legend view is toggled off

General Utilities 2-19 SRS QMS Gas Analyzer 3. Use the Next Item or Previous Item from the View menu to view the sequential logs (The time

v SRS QMS Gas Analyzer

2-20 Head Calibration and Security SRS QMS Gas Analyzer Analysis Procedure Make sure the RGA window is in either Analog mode or Histogram mode

Head Calibration and Security 2-21 SRS QMS Gas Analyzer Please refer to the RGA Tuning Chapter for more information about tuning and calibr

2-22 Head Calibration and Security SRS QMS Gas Analyzer Peak Tuning the RGA Head WARNING! The peak tuning procedure should be performed by qual

RGA On-line Help 2-23 SRS QMS Gas Analyzer • Press Undo ALL to revert to the initial settings, or • Press Factory Settings to recall fact

2-24 RGA On-line Help SRS QMS Gas Analyzer To see the entries for a topic, click the first letter of the word you want to look up, or press TAB

SRS QMS Gas Analyzer User’s ManualChapter 3. Measurement TechniquesThis chapter discusses procedures to help the user make accurate measurements with

3-2 CalibrationSRS QMS Gas AnalyzerCalibrationThe QMS has been calibrated at the factory to measure the partial pressure of nitrogen correctly. Fo

Calibration 3-3User’s ManualEffect of Total PressureIncreasing the total pressure at the inlet of the capillary will increase the flow through the

3-4 CalibrationSRS QMS Gas Analyzerrange of the QMS with respect to increasing the inlet pressure above the design point. The instrumenthas little

Calibration 3-5User’s ManualCalibration of Partial PressureAll quantitative calculations performed with the RGA rely on the assumption that there i

vi SRS QMS Gas Analyzer Fast Start • Connect the power cord to the QMS. Set the four switches on the control panel to off and turn on the ma

3-6 CalibrationSRS QMS Gas Analyzercontrol the filter (electron energy, focus voltage, ionizer current, and ion energy). In the equation above,the

Calibration 3-7User’s ManualThis completes the calibration. All modes of the software will now report partial pressure at the inlet tothe capillar

3-8 CalibrationSRS QMS Gas AnalyzerCalibration for Multiple Operating ConditionsThe QMS capable of being used over a variety of operating condition

Calibration 3-9User’s ManualThe Peak Tuning procedures described in this section allow the user to calibrate the mass scale and theresolution, ∆m10

3-10 CalibrationSRS QMS Gas AnalyzerGeneral ProcedurePeak tuning is a simple procedure that requires the introduction of two known gases into the v

Calibration 3-11User’s ManualLow Mass High Mass00.10.20.30.40.50.60.70.80.9115 16 17 18 19 20 21 22 23 24 25H20+Ar++00.10.20.30.40.50.60.70.80.980

3-12 CalibrationSRS QMS Gas Analyzer scale. An increase in RI causes the low end of the analog spectrum to displace towards lower masses(A small ef

Calibration 3-13User’s Manual(Slope), stored in the non-volatile memory of the RGA, to calculate the 8 bit settings of the DACaccording to the line

3-14 CalibrationSRS QMS Gas Analyzer• The effect is more significant at the higher masses and that is why we do this adjustment secondafter the wi

Calibration 3-15User’s ManualElectron Multiplier Tuning ProcedureAccurate quantitative measurements with the electron multiplier detector require t

vii SRS QMS Gas Analyzer Specifications Inlet Type capillary: available in stainless steel, PEEK, and glass lined plastic Flowrate 1 to 10

3-16 TechniquesSRS QMS Gas AnalyzerTechniquesCorrecting for the Chamber BackgroundEven with the sample flow and capillary flow valves closed, their

Techniques 3-17User’s ManualCorrecting for Multiple SpeciesAs discussed above, the QMS is calibrated at one mass number. Because every gas behaves

3-18 TechniquesSRS QMS Gas AnalyzerWhen the gas being measured is significantly hotter than the QMS system, condensation is likely andpresents a pr

SRS QMS Gas AnalyzerGlossaryThe following is a listing of some of the most important terms used throughout the SRS RGA OperationsManual. For a more c

GlossarySRS QMS Gas AnalyzerElectron Energy. The kinetic energy of the electrons (in eV) used for electron bombardment in theionizer. Note: In the SRS

GlossarySRS QMS Gas AnalyzerIonization efficiency. The ionization probability normalized to the probability of ionization of areference gas.Ionization

GlossarySRS QMS Gas Analyzercannot be differentiated from each other with most mass spectrometers. Note: Massspectrometers do not actually measure the

GlossarySRS QMS Gas AnalyzerResponse time - is a measure of the steepness of the response when a step change is presented at theinlet.RGA - residual g

SRS QMS Gas AnalyzerReferencesGeneral RGA informationDawson, “Quadrupole Mass Spectrometery and Its Applications”, AIP Press, NY, 1995.Drinkwine and D

GlossarySRS QMS Gas Analyzer

viii SRS QMS Gas Analyzer protection class IP44 Materials (see full materials list for details) construction: SS304 and SS316 insulators: alu

Technical Reference Manual QMS 100 Series Gas Analyzer Version 3.1 (4/2009)

CertificationStanford Research Systems certifies that this product met its published specifications at the time ofshipment.WarrantyThis Stanford Resea

SRS QMS Gas Analyzer Technical ReferenceTable of ContentsSafety...

iv SRS QMS Gas Analyzer SafetyLine VoltageThe QMS system is specified for power line of either 110 V / 60 Hz or 220 V / 50 Hz. The diaphragmpump wi

vTechnical ReferenceSpecificationsInletType capillary: available in stainless steel, PEEK, and glass linedplasticFlowrate 1 to 10 milliliter per m

vi SRS QMS Gas Analyzer Recommended bakeouttemperature100 - 250 CIonizer:Design Open ion source. Cylindrical symmetryOperation Electron impact ioniz

viiTechnical Reference

viii SRS QMS Gas Analyzer Materials ListSRS receives many requests for information about corrosion compatibility. It is our policy not to statethe

ixTechnical ReferenceCommand ListInitialization Name Description Parameters EchoID Identification Query ? ID StringIN Initialization 0,1,2 STATUS

x SRS QMS Gas Analyzer HS Histogram Scan Trigger 0-255, *, none Ion CurrentsMF Final Mass 1-M_MAX, *, ? Query responseMI Initial Mass 1-M_MAX, *, ?

ix SRS QMS Gas Analyzer Materials List SRS receives many requests for information about corrosion compatibility. It is our policy not to state

xiTechnical ReferenceError ReportingName Description Parameters EchoER STATUS Byte Query ? Query responseEP PS_ERR Byte Query ? Query responseED D

SRS QMS Gas AnalyzerChapter 1. Principles of OperationThe QMS consists of two main subsystems: the gas handling inlet and the mass spectrometer. Thes

1-2 Internal View SRS QMS Gas Analyzer Internal View Figure 1. Main components of the QMS are labeled: 1. microcontroller 2. aperture 3. s

Overall System 1-3Technical ReferenceOverall SystemThe QMS was designed to be a self contained instrument. Only line power is required to opera

1-4 Overall SystemSRS QMS Gas AnalyzerThe pressure gauge operates on 15 VDC, which is provided by the microcontroller. The gauge has on-board elec

Pressure Reducing Inlet 1-5Technical ReferencePressure Reducing InletThe gas handling subsystem is designed to achieve several goals:• reduce t

1-6 Pressure Reducing InletSRS QMS Gas AnalyzerFlow CalculationsThe pressure and flowrates of the sampled gas can be calculated with simple formula

Pressure Reducing Inlet 1-7Technical Referencewhere Cbd is the conductivity of the tube from the tee to the diaphragm pump. The flow through th

1-8 Pressure Reducing InletSRS QMS Gas AnalyzerThese last two characteristics greatly simplify the selection of alternate capillaries and is discus

Pressure Reducing Inlet 1-9Technical ReferenceTurbo PumpThe pump attached to thespectrometer chamber is hybridturbomolecular/drag pump. Thehybr