New Sensing technology using new materials (crystals) from Tohoku University
Frequency is decreased by mass load effect of deposited on the surface of the sensing crystal. This crystal microbalance mechanism enables to detect weight as little as nanogram level by frequency variation “Δf”.
It is applied to the high temperature of “ALD process” used for the film deposition process of the most advanced semiconductors. Although it is possible to expect reduction of crystal defects and new high-performance in the film due to the high temperature, the conventional measurement method makes it impossible to measure reliable data because the quartz crystal is unstable in a high temperature environment.
We have developed a film deposition process sensor using a new material that is stable even in a high temperature environment.
Quartz used in conventional sensors causes deterioration of piezoelectric performance and composition abnormalities such as crystal twinning at over 300 °C, but the newly developed piezoelectric crystal can withstand high temperatures from 300 °C to nearly 1000 °C. In addition, there is little frequency deviation due to temperature, enabling highly accurate sensing. In the future, we plan to take advantage of this material and aim to develop applications in different fields such as pressure sensors under high-temperature.