The first step in manufacturing blank CD discs is to create a glass
master with a Laser Beam Recorder, just as you would do for a CD-ROM.
Instead of etching pits and lands into the photo resist or non photo resist on
the glass as would be done for a factory produced data or audio CD.
Electroforming
Once the glass master for the CD has been written, it is then tested,
silvered, and is ready to be electroplated. The disc is now electrically
conductive. It is placed in a reservoir with an electrolyte solution of
nickel sulphamate. Electrical current is applied to the glass master, first
at a low level, then gradually increased. This current produces a metal
layer on the glass in a few hours.
This nickel copy of the glass master is called the called the metal
father, and can be used as a stamper to replicate CD media. However, if the
replication run is large, the metal father goes back to the electroplating
process to create metal mothers. These metal mothers are used to make metal
sons, which are identical to the fathers.
