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Product Briefing Outline: INFICON has introduced the XTC/3 a thin film deposition controller for single and multiple-layer processes. The XTC/3 utilizes INFICON's patented ModeLock technology that provides mode hop prevention while in operation. The controller is designed to provide accurate control of deposition rate and thickness, for virtually any number of layers, while it is easy to install and offers high reliability, according to the company.

Problem: Conventional quartz crystal in the sensor head determines the frequency of operation of the RF power supply. The coupling between the crystal and the RF drive electronics at the fundamental frequency weakens and eventually crashes when the crystal hops to a higher harmonic frequency. The measurement circuit, based on the history of changes in the fundamental frequency, is unable to resolve the information and the measurement 'fails.'

Solution: The ModeLock measurement system forces the crystal to remain in its fundamental frequency and virtually eliminates 'mode hopping.' This patented system provides crystal-frequency information with a precision unobtainable from conventional oscillator systems, according to the company. Monitors and controllers using ModeLock technology maintain a single measurement resolution of .005Å, even at ten measurements per second. This is particularly important for low deposition rate processes. With an update rate of 0.15 MHz, ModeLock functions much faster than any significant film thickness change can occur. It also extends the crystal's useful life for all materials. The technology also makes possible continuous computation of acoustic impedance ratios during deposition - critical to maintaining thickness accuracy when depositing layered or alloy materials on a single crystal.

Applications: XTC/3M multiple-layer model supports up to 99 processes, 999 layers, 32 films, 2 sensors, and two sources. The XTC/3S single-layer model supports up to 9 films, 2 sensors, and two sources.

Platform: Controllers include the RateWatcher electronics, a life extender for crystal sensors used for in-line or automatic load-locked sputtering processes. If a shuttered crystal sensor is used with any controller, the deposition rate can be periodically, rather than continuously, checked. While the shutter is open it adjusts the power to the pre-set deposition rate, then closes the shutter and holds the adjusted level until the next check.

Availability: May 2006 onwards.