Hermetic Ceramic-Metal Feedthroughs

Ceramaseal^® ceramic-to-metal feedthroughs are custom assemblies for the passthrough of substances or energy from outside a hermetically-sealed chamber to the inside. They provide hermeticity and electrical isolation and remain leak-free in high and ultra-high vacuum.

Ceramaseal^® feedthroughs are ideal for all applications that require both hermeticity (vacuum-tightness) and electrical insulation. Ceramic-to-metal feedthroughs not only offer absolute freedom from leaks in vacuum and ultra-vacuum environments, but are also resistant to high temperatures, cryogenic temperatures, high pressure, and aggressive chemicals. This makes them ideal for use under such conditions.

Ceramic-to-metal feedthroughs from Ceramaseal^® are defined by the requirements for installation, insulation, and conductor material. The method of interconnection is flexible and often subject to specific customer requirements. CeramTec offers a wide selection of Ceramaseal^® plug connectors and feedthroughs with interconnection (connectors and multipin connectors). Ceramaseal^® feedthroughs can be divided into the following types:

Feedthroughs for low voltages (up to 12 kV)
Water-cooled feedthroughs and RF feedthroughs
High-voltage feedthroughs (20 to 100 kV)

Ceramaseal^® high-frequency and ultrahigh-frequency feedthroughs (RF feedthroughs) are engineered to perform efficiently in a variety of RF applications including sputtering, plasma generation, and induction heating.

Feedthrough applications

Semiconductor processing equipment
Particle accelerators
Furnaces
Analysis equipment
Coating applications in vacuum environments
Satellite instrumentation
X-ray equipment

Ceramaseal^® ceramic-to-metal feedthroughs use only inorganic materials. The insulators are made from high-purity, high-strength, low-loss alumina ceramics. Metals include Kovar^®, stainless steel, nickel, copper, nickel-iron alloys, cupro-nickel alloys, molybdenum, Alumel^® and Constantan^®. In corona-free designs, standard design practices consider electrical characteristics such as flashover, corona breakdown, creep, dielectric strength and puncture resistance.

Braze materials used are silver, copper, silver-copper, or gold-copper alloys. Metalization processes include both refractory-metal and active-metal metalizations, depending on the size, geometry, and performance requirements for the feedthrough. CeramTec uses advanced techniques and methods to control and monitor critical processes, including 100 percent helium leak testing and x-ray measurements for metalization control.

Standard installation mountings for Ceramaseal® ceramic-to-metal feedthroughs include: