Stanford Research Systems PG108 Convection-Enhanced Vacuum Gauge with Compatible Bayard-Alpert Ion Gauge

Overview

The Stanford Research Systems PG108 is a convection-enhanced, portable vacuum measurement system engineered for high-fidelity pressure monitoring across an exceptionally broad dynamic range—from atmospheric conditions (1000 Torr) down to ultra-high vacuum (1 × 10⁻⁸ Torr). Unlike conventional thermocouple or capacitance manometers, the PG108 leverages convection-enhanced thermal conductivity principles at higher pressures while seamlessly transitioning to ionization-based measurement via an integrated Bayard-Alpert (B-A) ion gauge at lower pressures. This hybrid architecture eliminates the need for multiple discrete sensors in multi-regime vacuum processes. The all-metal construction—featuring a copper knife-edge sealing interface—ensures compatibility with bake-out procedures up to 150 °C and long-term stability under cyclic thermal stress. Its modular design allows direct coupling with SRS’s IGC100 Intelligent Gauge Controller, enabling real-time digital readout, analog output, and remote interrogation via RS-232 or Ethernet.

Key Features

• All-metal vacuum housing with helium-leak-tight copper knife-edge seal, rated for UHV-compatible mounting and repeated bake-out cycles.
• Convection-enhanced thermal sensor for accurate, drift-resistant measurement from 1000 Torr down to ~10⁻³ Torr—optimized for rapid response in dynamic gas load environments.
• Integrated B-A ion gauge interface supporting interchangeable glass, metal, and UHV-rated ionization sensors—enabling application-specific selection based on required ultimate pressure, chemical compatibility, and radiation tolerance.
• Flexible filament architecture: supports ThO₂/Ir (oxygen-tolerant, low electron emission noise) or tungsten (high temperature resilience) filaments, in either single- or dual-filament configurations for redundancy and extended operational lifetime.
• Full compatibility with SRS IGC100 controller—including automatic gauge identification, filament protection logic, emission current regulation, and auto-zeroing routines—ensuring compliance with ISO 27893 and ASTM E1672 standards for vacuum instrumentation calibration traceability.
• Compact, portable form factor with integrated power conditioning and EMI-hardened signal paths—designed for field deployment in semiconductor tool maintenance, accelerator beamline diagnostics, and space simulation chamber validation.

Sample Compatibility & Compliance

The PG108 system is chemically inert toward common process gases (N₂, O₂, Ar, He, H₂, CO, CO₂, CH₄) and compatible with hydrocarbon-free vacuum environments. When paired with metal-envelope or UHV-rated B-A gauges, it maintains measurement integrity in the presence of reactive species such as NH₃, Cl₂, or WF₆—provided appropriate filament material selection and operating protocols are followed. The system meets electromagnetic compatibility requirements per CISPR 11 Class B and is designed to support audit-ready data acquisition workflows compliant with FDA 21 CFR Part 11 when used with validated IGC100 firmware and time-stamped logging configurations. It is routinely deployed in ISO/IEC 17025-accredited calibration laboratories for transfer standard verification against primary manometers.

Software & Data Management

The PG108 operates natively within the SRS Vacuum Control Suite—a Windows-based application supporting real-time plotting, multi-gauge synchronization, alarm thresholding, and CSV/Excel export with metadata tagging (timestamp, gauge ID, controller firmware version, ambient temperature). Raw sensor outputs (ion current, convection voltage, emission current) are accessible via SCPI command set over RS-232 or TCP/IP. For integration into SCADA or MES platforms, OPC UA and Modbus TCP drivers are available through SRS’s certified third-party middleware partners. All data streams include built-in checksums and hardware-level timestamping synchronized to UTC via NTP—ensuring integrity for GLP audit trails and long-term trend analysis.

Applications

• Semiconductor fabrication: In-situ pressure profiling during PECVD, sputtering, and etch chamber conditioning.
• Particle accelerator vacuum systems: Beamline interlock monitoring and residual gas analysis pre-conditioning.
• Space environment simulation: Thermal vacuum chamber qualification with continuous pressure logging across pump-down, bake-out, and hold phases.
• Research plasma physics: Time-resolved pressure mapping in pulsed discharge experiments where rapid transients (<100 ms) must be resolved.
• Materials science gloveboxes: Monitoring inert atmosphere integrity during metallurgical synthesis and battery electrode processing.
• Calibration laboratory reference standards: Serving as a transfer standard between primary capacitance diaphragm gauges and secondary ionization references.

FAQ

What vacuum ranges does the PG108 cover with its convection and ionization modes?

The convection-enhanced sensor covers 1000 Torr to ~1 × 10⁻³ Torr; the connected Bayard-Alpert ion gauge extends measurement down to 1 × 10⁻⁸ Torr, depending on gauge type and filament configuration.
Can the PG108 operate continuously at 150 °C?

Yes—the all-metal construction and copper knife-edge seal are rated for sustained operation at 150 °C, including under full vacuum, provided the attached ion gauge is similarly rated.
Is the PG108 compatible with non-SRS controllers?

It is electrically and protocol-compatible with any controller supporting standard B-A ion gauge interfaces (e.g., emission current input, filament bias, collector voltage), though full feature access (auto-identification, filament protection) requires the IGC100.
How is calibration traceability maintained?

Each PG108 unit ships with NIST-traceable calibration certificates for both convection and ionization channels; periodic verification follows ISO 27893 Annex D procedures using certified reference gauges.
Does the system support dual-filament redundancy for unattended operation?

Yes—when configured with a dual-filament B-A gauge and IGC100 firmware v3.2+, automatic filament switchover occurs upon open-circuit detection, preserving uninterrupted measurement continuity.