Vacuum Equipment- Thin Film Deposition Equipment- Thin Film Controllers- Thin Film Monitors- Quartz Crystals

Sigma Instruments offers an extensive selection of commonly used quartz crystal feedthroughs, sensors and multi-channel monitors, cables, quartz crystals, accessories and replacement parts for use in semiconductor, optical and industrial thermal deposition processes. Custom feedthroughs are available with a variety of flanges in all sizes.

Our coating instrumentation products support one of the more popular methods of thin film measurement and rate control the crystal monitor, which utilizes the piezoelectric properties of a quartz crystal.

The electrical characteristics of the crystal, which is held in place by the sensor, change during deposition. Single sensors are generally used for short deposition runs, whereas, dual sensors allow for longer runs. Dual sensors require an airline to operate a pneumatic shutter which covers one crystal at a time. The sensor is either welded to the feedthrough or attached with connectors. Most sensors are available with cooling lines.

The application determines the correct choice of sensor. The sensor determines compatible feedthroughs and cabling. The chamber determines the appropriate feedthrough and flange. For application temps up to 150°C, electrical connection between the sensor and feedthrough is accomplished with a vacuum coaxial cable. A bakeable, one piece sensor/feedthrough replaces the standard in-vac cable with a stainless steel high-temp coaxial line for high temperature applications up to 300°C.

The feedthrough is the air-to-vacuum connection between the sensor and the oscillator. The feedthrough transfers the quartz crystal’s piezo-electric vibrations to the oscillator via a short coaxial cable. The oscillator conditions the signals and transfers them to the monitor via another coaxial cable. The monitor then measures, interprets and displays the thickness, rate and frequency of deposition. Nor-Cal’s thin film deposition monitors are available with up to six independent channels to read six single sensors or three dual sensors simultaneously. Each sensor requires its own cabling and oscillator. Contact our sales staff for help with your system configuration.