Pfeiffer Vacuum ASI35 Helium Mass Spectrometer Leak Detection Module

Overview

The Pfeiffer Vacuum ASI35 is a compact, high-sensitivity helium mass spectrometer leak detection module engineered for OEM integration into automated, application-specific leak testing platforms—particularly those deployed in the semiconductor, microelectronics, and advanced packaging industries. Operating on the principle of magnetic sector mass spectrometry, the ASI35 selectively ionizes helium atoms introduced into a vacuum chamber and separates them by mass-to-charge ratio (m/z = 4) using a precision magnetic field. This enables quantitative detection of helium tracer gas escaping from sealed electronic components—such as hermetic ceramic packages, MEMS sensors, RF filters, and power modules—under controlled vacuum conditions. With a specified minimum detectable leak rate of 5 × 10⁻⁷ mbar·L/s in vacuum mode, the ASI35 delivers the sensitivity required to validate integrity at the sub-micron defect level, supporting reliability assurance in mission-critical applications where failure due to moisture ingress or atmospheric contamination is unacceptable.

Key Features

• Modular architecture optimized for embedded system integration—no standalone user interface or internal vacuum pump; designed for direct control via external PLC or host PC through RS-232/RS-485 or optional Ethernet/IP interface.
• High-stability quadrupole mass filter combined with cold cathode ion source ensures long-term signal reproducibility and resistance to hydrocarbon contamination common in production environments.
• Integrated helium discrimination logic minimizes false positives from background helium or residual air peaks (e.g., H₂⁺, CH₄⁺), enhancing measurement specificity in multi-unit test cells.
• Compact footprint (190 × 120 × 75 mm) and low power consumption (<25 W) facilitate installation in space-constrained test chambers or inline production fixtures.
• Factory-calibrated sensitivity traceable to national metrology institutes; supports periodic verification using certified helium standard leaks (e.g., 1 × 10⁻⁸–1 × 10⁻⁶ mbar·L/s).

Sample Compatibility & Compliance

The ASI35 module is intended exclusively for use in evacuated test chambers where samples undergo pre-conditioning—typically pressurization with helium (e.g., 2–5 bar for 30–120 min) followed by evacuation and sniffing or vacuum testing. It accommodates rigid and semi-rigid electronic enclosures up to 5 L internal volume when integrated into custom-built test stations. The module itself complies with CE marking requirements under the EU Electromagnetic Compatibility Directive 2014/30/EU and Low Voltage Directive 2014/35/EU. When deployed within validated leak test systems, it supports compliance with industry-specific quality frameworks including IATF 16949 for automotive electronics, MIL-STD-883 Method 1014 for military-grade hermeticity, and JEDEC J-STD-033 for moisture-sensitive device handling protocols.

Software & Data Management

As an OEM component, the ASI35 does not include proprietary GUI software. Instead, it provides standardized ASCII command protocol (Pfeiffer Vacuum “HiPace”-compatible syntax) for seamless integration with customer-developed test executive software—such as NI TestStand, Keysight PathWave, or custom LabVIEW/C# applications. All leak measurement data (raw ion current, calculated leak rate, timestamp, chamber pressure status) are output in ASCII format with configurable sampling intervals (100 ms–10 s). For regulated environments, the host system may implement audit trail functionality, electronic signatures, and data archiving aligned with FDA 21 CFR Part 11 requirements—provided the host platform includes appropriate validation documentation and change control procedures.

Applications

• Final hermeticity verification of ceramic QFN, LGA, and BGA packages prior to shipment.
• In-process leak screening of wafer-level chip-scale packages (WLCSP) after lid bonding.
• Reliability qualification testing of MEMS oscillators, accelerometers, and pressure sensors exposed to thermal cycling or humidity bake.
• Root cause analysis of field returns suspected of seal degradation using comparative leak rate trending across production lots.
• Integration into fully automated inline leak test cells operating at >30 units/hour throughput in high-volume semiconductor assembly facilities.

FAQ

Is the ASI35 supplied with a vacuum pump or foreline trap?
No—the ASI35 is a mass spectrometer-only module and requires external roughing and high-vacuum pumping (e.g., turbomolecular + dry scroll pump combination) and appropriate gas ballast and cryo-trapping to maintain base pressure below 1 × 10⁻⁵ mbar.
Can the ASI35 be used in sniffer (pressure-rise) mode?
No—it is configured exclusively for vacuum-mode operation; helium detection during pressurized testing requires a separate handheld or benchtop sniffing probe connected to a compatible analyzer.
What calibration documentation is provided?
Each unit ships with a factory calibration certificate indicating sensitivity at m/z = 4, measured against NIST-traceable helium standard leaks; full calibration reports are available upon request for IQ/OQ validation support.
Does Pfeiffer Vacuum provide SDKs or driver libraries?
Yes—Pfeiffer offers Windows-compatible DLLs and .NET assemblies, as well as Linux-compatible shared libraries and Python bindings, all documented in the ASI35 OEM Integration Manual (Document No. 510-800-001-EN).
Is firmware upgrade capability supported remotely?
Firmware updates require physical connection via RS-232 and execution of Pfeiffer’s proprietary update utility; remote update over Ethernet is not supported for security and validation integrity reasons.