Keywords
Citation
(2002), "Low temp glass-to-metal preform seals for optic fibres", Anti-Corrosion Methods and Materials, Vol. 49 No. 6. https://doi.org/10.1108/acmm.2002.12849fad.006
Publisher
:Emerald Group Publishing Limited
Copyright © 2002, MCB UP Limited
Low temp glass-to-metal preform seals for optic fibres
Low temp glass-to-metal preform seals for optic fibres
Keywords: Seals, Optics, Fibre optics, Glass
Good news for laser diode packaging comes from Production Equipment Sales Ltd (PESL) in the shape of the DIEMAT range of glass preforms for use in hermetically sealing glass to metal. Specifically, small diameter glass tube feed-throughs may be sealed by a small donut shaped glass preform to a Kovar package at temperatures as low as 320°C. The preform is said to replace solder at a fraction of the cost by simplifying the manufacturing process. In addition, it is reportedly eliminated along with the plating requirements, voiding, stress concentrations, flux residue cleaning, or non oxidising atmospheres associated with solder. Designated as DM2700PF, these clean sealing preforms can, we are told, be processed in a matter of seconds without residue and are available with hole sizes as small as 0.010 in.
The DIEMAT process features a preformed glass collet which fits over the optic fibre. The preform (with fibre) is then induction heated in a metal head, (generally to just over 350°C) this flows the collet into the header while maintaining central alignment of the fibre and provides a hermetic glass to metal seal in the laser package.
This process is said to replace solder and associated need for fibre metalisation, it is stated to be fatigue and corrosion resistant without creepage. The no-flux process reportedly takes less than 10 s, has high adhesion and proven reliability associated with low thermal stresses. Preforms are available in a variety of sizes ranging from 0.010 in. ID, donuts to large forms up to 1 in. or larger of various shapes.
Details available from: PESL, Tel: +44 (0) 1825 766644; Fax: +44 (0) 1825 766464; E-mail: mail@peslcixco.uk; Web site: www.pesl.win-uknet