Introduction to Vacuum and Hermetic Feedthroughs

Feedthrough devices (Feedthrough) are key components in the fields of vacuum technology and hermetic sealing, widely used in semiconductor manufacturing, aerospace equipment, and medical devices.

They allow electrical signals, power, or fluids to pass through vacuum chamber walls while maintaining strict hermetic seals to prevent leakage and contamination.

This article will explore in depth what a Feedthrough is, Feedthrough wiring, vacuum Feedthrough, and hermetic Feedthrough core concepts.

1.Basic Definition of Feedthrough

A Feedthrough is a specialized component that allows electrical signals, power, fluids, or mechanical motion to pass through vacuum chamber walls, pressure barriers, or sealed enclosures while maintaining hermetic integrity.

Its core lies in the perfect combination of insulators and conductors, ensuring the internal environment remains unaffected by external interference.

It is commonly used in electrical feedthrough devices, supporting applications from low to high voltage.

2.Concept and Role of Feedthrough Wiring

Feedthrough wiring refers to the conductor routing part within feedthrough devices, typically including pins, cables, or coaxial structures.

It is responsible for transmitting low-voltage signals, high-power electricity, or RF signals, while also providing electromagnetic shielding.

Common Feedthrough Wiring Forms：

• Single-pin feedthroughs for simple signals
• Multi-pin feedthroughs for complex instrumentation
• Coaxial structures for RF applications
• Power-type feedthrough wiring designed to handle high currents without overheating

3.What is a Vacuum Feedthrough?

Vacuum Feedthroughs are specifically designed for high vacuum or ultra-high vacuum (UHV) environments, preventing gas leakage down to levels as low as 10⁻¹⁰ Torr.

They typically use metal sealing flanges such as CF, KF, or ISO, and feature excellent resistance to high temperatures and corrosion.

Overview of Vacuum Feedthrough Types：

• Electrical vacuum feedthroughs
• Coaxial vacuum feedthroughs
• Multi-pin vacuum feedthroughs
• Power vacuum feedthroughs

Do you need samples of vacuum feedthrough products or guidance on options? Visit our vacuum feedthrough product page to learn more.

4.Standards for Hermetic Feedthroughs

Hermetic Feedthroughs emphasize permanent sealing, with helium leak rates typically less than 10⁻⁹ atm·cc/s, or even lower.

They are suitable for extreme environments such as aerospace and medical implants, focusing more on long-term reliability compared to standard vacuum feedthroughs.

Hermetic Sealing Techniques：

• Ceramic-to-metal brazing (Ceramic metallization technology)
• Glass-to-metal sealing

These seals are verified through helium mass spectrometry leak detection to ensure integrity.

5.Common Types Classification and Materials & Processes

By function:

• Electrical feedthroughs (power, instrumentation, coaxial, RF, thermocouple)
• Fluid feedthroughs
• Mechanical motion feedthroughs

By installation method:

• Flange-type
• Threaded
• Welded

Key Materials and Processes：

• Insulators: High-purity alumina ceramics (Al₂O₃)
• Conductors: Stainless steel, molybdenum, or Kovar alloys

The core manufacturing process is metallized ceramics, where alumina surfaces are metallized and then brazed to metal pins to achieve permanent, hermetic connections.

Would you like to design a vacuum or sealing system? Obtain one-stop material selection and product customization services through the contact form.

6.Application Fields and Selection Guide

Main Application Scenarios：

• Vacuum coating equipment
• Semiconductor manufacturing
• Particle accelerators
• Medical instruments
• Nuclear and research equipment

Selection Considerations：

When choosing a feedthrough, consider:

• Required vacuum level
• Voltage and current ratings
• Operating temperature range
• Acceptable leak rate
• Material compatibility

For long-term stability, metallized ceramic hermetic feedthroughs are generally recommended.

Related Education Links:

• NASA: Vacuum Technology Overview
• CERN: Particle Accelerator Vacuum Systems
• ScienceDirect: Hermetic Feedthrough Research

7.Conclusion: Future Outlook for Feedthrough Devices

Feedthrough devices serve as critical bridges in vacuum and hermetic technology and are indispensable in high-tech industries.

With increasing demands for miniaturization and high-frequency performance, metallized ceramic processes will continue to evolve and optimize.

A solid understanding of Feedthrough concepts, types, and applications helps engineers design more reliable and efficient systems.

Would you like to customize high-performance feedthrough equipment or obtain a solution?
Contact us through the contact form to obtain professional technical support and prompt responses.