Metalizing

Thick-film metallizing can be applied to fired ceramics to provide a bonding surface for subsequent attachment of chips or metal parts such as circuit leads, flanges, heat spreaders, seal rings, etc. The most commonly used technique for thick-film metallizing is screen printing, and spraying, roller coating and hand application are also used.

A molybdenum-manganese refractory metal composition is primarily used by American Beryllia Inc. and after application, it must be sintered at high temperature (1400ºC) before subsequent processing. Typical thicknesses for the fired metallizations are 100 to 1000 micro inches (2.5 to 25 microns). Sputtered thin film metallized patterns, which permit very tightly spaced fine lines to be applied to a ceramic substrate, are also available to meet special needs such as microwave circuits.

Precision Grinding

Both manual and automatic grinding techniques are used to achieve precise physical dimensions not possible in an "as-fired" part. Available methods include centerless, cylindrical, surface and inside diameter grinding using diamond wheels. Dimensional tolerances of +0.0001 inches (0.0025mm) can be met with simple and complex geometries.

Lapping and Polishing

Lapping and polishing is used to achieve specific surface finish, flatness and parallelism. In the lapping process, revolving flat surfaces abrade the ceramic part with a diamond or other abrasive lapping compound. The surface finish is controlled through selection of the proper abrasive, pressure and lapping cycle.

Dicing

Advanced, computer-controlled dicing equipment with diamond saw blades, similar to machines used for dicing integrated circuit wafers, is used to cut ceramic wafers into predetermined shapes and sizes. Linear cuts at any desired angle are also possible with this equipment.

Beryllium Oxide Manufacturing Process