Ultra-Thin Film Aluminum Oxide Technology - AquaXact 1688

The AquaXact 1688 ultra-thin film technology is based on major advances in micro layer deposition and metal oxide sciences. It provides measurements with a sensitivity several orders of magnitude larger than of those made with other technologies. The Servomex AquaXact 1688 sensor results are free of drift and insensitive to temperature changes.

Operating Principle:

Aluminum Oxide (Al2O3) sensors measure the capacitance between an aluminum core and a gold film deposited on top of the oxide layer, which varies with the water vapor content in the pores of the oxide layer. Three fundamental structural improvements in the oxide layer give AquaXact 1688 sensors much increased sensitivity and stability: the Servomex sensors have a much thinner oxide layer, a betterdefined barrier layer between the aluminum and the aluminum oxide, and a unique pore geometry enhancing the entrapment of water molecules.

Ultra-Thin Layer Technology:

The ultra-thin Aluminum Oxide AquaXact 1688 sensors are manufactured without compromising transmitter strength. The thinner oxide layer of the sensors results in much higher capacitance changes since capacitance is inversely proportional to the distance of the capacitor’s plates from each other. The thinner layer also means that water molecules will travel faster in and out of the pores. Servomex Aluminum Oxide sensors therefore respond several times faster than conventional Al2O3 sensors.