My crystal’s aren’t lasting as long.
Crystal life issues can be very complex to immediately resolve. However, there are some general conditions that can lead to lower life and/or less desirable performance. The information below is a general guide to resolving issues. However, if you need additional help, please complete this form before contacting us.
If you have suddenly noticed that your crystals aren’t lasting as long or the rate is “noisy,” please observe the following:
Has your evaporation material changed?
If you have switched to a new material and not changed your crystal type accordingly (I.e. you’re using gold crystals but should now use alloy) this can be a strong influence on crystal life. Many times we observe customers trying to interchange crystals between different processes but not anticipating poor performance. Please refer to our Buyers Guide to choose the proper crystal for your application.
Have you introduced heat or plasma to your process?
In the case of AT Crystals, suddenly introducing heat in the chamber could cause issues with frequency drift and erratic rate. These are issues addressed by our RC, HT, and SQ crystals. Anything over 150 degrees C will effectively render an AT crystal useless. For more technical information on AT quartz click here.
Have you increased the thickness of your process?
If you have increased your target thickness this could lead to overloading the crystal surface and dramatically reducing life. A crystal only has a limited carrying capacity, and while you might have been OK coating with your original thickness, increasing this might be just enough to go over the threshold.
Have you increased the evaporation rate of your process?
Dramatically increasing the rate, could lead to film stress on the crystal surface and effect resonance, thereby reducing life. In the simplest of terms, film stress is the microscopic fracturing of the crystals electrode layer. When this happens, the crystal will begin to resonate erratically and either register as dead or substantially lower health.
How old is your monitor system and/or oscillator?
Aging hardware is often the culprit for inexplicable performance issues. Circuitry in old monitors can begin to degrade the very fine measurement characteristics of a QCM and begin to display inferior performance.
Is your crystal cable integrity sound?
Are there and cracks in the jacket or are the connections loose? Is the cable bent excessively? Ensure the cable is not defective, by testing with a multimeter, and replace if necessary.