please pay attention to the cassettes

[Lian Zhang]

Users,

Someone apparently messed up a wbdiff cassette with a wbnonmetal
cassette.  Right now a wbdiff cassette is sitting in a wbnonmetal box and
a wbnonmetal cassette was left in the wbdiff dump rinser.

Please note that your wafers can go from wbnonmetal but not the
cassettes.  Cassettes in the lab are all marked with a colored dot on the
front side, and every wet bentch has a uniqe color.

Please always pay attention to what cassette you are using.

Lian