Abstract :
A new process is described whereby quartz crystal units are vacuum baked, plated, and sealed during one and the same pump-down cycle. The crystal blanks are mounted by means of gold rivets and plated with copper. The performance potential of the resulting "clean" and "strain-free" crystal units is demonstrated at 62 MHz where aging rates below ±5×10-10per week and Q values of 200 000 are obtained.
