Thin film controllers and control units with quartz oscillators

Thin film controllers and control units with quartz oscillators 

The selection of the right crystal holder thus plays an important role in all measurements with quartz oscillators. Various crystal holder designs are recommended for the different applications with or without shutter, bakeable for UHV, double crystal holder or crystal six as well as special versions for sputter applications. In addition to these important and more mechanical aspects, the advances in measuring and control technology and equipment features will be discussed in the follovi/ing. 

Since there is still a problem with quartz capacity (i.e. the maximum possible coating thickness of the quartz at which it still oscillates reliably) despite refined technology, a number of approaches have been developed to expand this capacity  

The use of several crystals, one behind the other, in a multiple crystal holder with automatic change and data updating in the event of imminent failure of a quartz CrystalSix. 

The RateWatcher function, in which the quartz is alternately exposed to the coating beam for a short time until all measurements and regulation have been carried out and then remains covered by a shutter for a longer period of time. 

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