99.6% alumina ceramic substrates are most often used in thin film applications and are commonly called as thin film Ceramic substrates. In the as-fired time, flatness, surface imperfections, thickness tolerances and surface finish may not meet required conditions of sensitive applications.
Lapping provides the desired flatness and thickness tolerance, with a surface finish typically in the 8 to 12 microinch range.
Polish will make the surface defect-free and improve the finish to 0.5 microinch with good flatness and thickness tolerances.We can bring alumina ceramic substrate thickness down to 0.001″ with either a lapped or polished finish. The surface finish for 96% Alumina ceramic may be as rough as 30 microinches.Our lapping process will give desired thickness tolerance and flatness. The thicker of the finished substrate, the better flatness we can achieve.Most of thick film do not require polished substrates. 96% Alumina ceramics can be polished, although not as highly as 99.6% Alumina.