Since the founding of the Durakool name over 70 years ago, our HermaSeal division has supported our Relay and Switch product line with in-house design and manufacturing of hermetic glass-to-metal seals, feed-throughs and metal-to-metal vacuum brazing. Requirements for unique and intricate seal components, which must withstand extreme challenges, are our speciality. Advanced, characteristics like:
Can all be done simultaneously using our proprietary processing. Our in-house capabilities continue to supply various niche applications with this core expertise; HermaSeal is here to support your needs.
HermaSeal is capable of manufacturing transistor packages, quartz crystal packages, housings for photodiodes, hybrid packages, diode housings, battery and power feed-throughs, sensor packages, microwave packages, and many other custom designs.
TYPES OF SEAL AVAILABLE
STANDARD PRODUCT RANGES INCLUDE
● TO-Series headers
● Diode packages
● Single pin
● Multiple pins
● Flange mounted packages
● Sight Seals Etc.
If you require an application specific hermetic seal or combination Glass/Ceramic/Metal assembly, HermaSeal would be pleased to provide engineering support with your design.
● Excellent electrical insulation
● High hermeticity
● Automotive Electronics
● Pressure resistance
● Pressure Sensors
● Corrosion resistance
● Battery Terminals
● High operating temperature
● Mechanical strength
● Easy final assembly (i.e. welding or wire bonding)
● High reliability
COMPRESSION SEALS: The coefficient of thermal expansion of the header/seal body greatly exceeds that of both the glass and the electrode(s). The external metal component shrinks to form a compression ring around the glass. Assemblies of the available combinations are shown in the table below.
Typical compression seals will withstand extreme temperatures, in some cases -454o F (-270o C) to 842o F (450o C) with no loss in integrity.
MATCHED SEALS: The coefficient of thermal expansion of the metal components and the glass are similar. The hermetic seal is typically made by forming a bond between the glass and the oxide created on the metal components prior to sealing. Assemblies are available in the following combinations of materials:
Matched seals are more susceptible to temperature excursions, and are not recommended for applications exceeding 85o F (-65o C) to 482o F (250o C).
● Alkali Barium, Lead Silicate, Potash Lead, Soda Lime
● Borosilicate (Alkali, Barium, Soda, Potash)
Typical Characteristics offered by our seal assemblies
● Insulation resistance ranges from 1010 to 1012 Ohms. ● Breakdown voltage 40 VAC/55 VDC per radial .001 of glass between header and electrode ● Hermeticity 1.0 x 10-9 1.0 x 10-10Atm cc/sec (mbar l/s) He.
HermaSeal offer a variety of high quality surface finishes to meet the application requirements. These include but are not limited to:
● Good corrosion protection ● Good wire bonding ● Good solderability with flux ● Uniform thickness ● Good weldability
● Good corrosion protection ● Good solderability ● Excellent pre-plate for Au
Pure Au flash
● Improved solderability ● Protects against tarnish/oxidation
● Good wire bonding ● Excellent solderability without aggressive flux
● Wear resistant protection for contacts, plugs, connectors
Ag – Silver
● Excellent solderability ● High electrical conductivity
Sn – Tin
● Improved corrosion protection ● Very good solderability