A level sensor for the semiconductor industry
In a proof-of-concept study, Hittech Multin successfully designed and built a cost-efficient level sensor, specifically aimed at semiconductor applications, using mostly off-the-shelf parts and a self-developed processing algorithm.
The target measurement stability was 50 nm. Experiments on a 300-mm wafer showed a short-term instability between 6.4 nm and 10E2 nm, at the centre and the edge of the measurement range, respectively. Read all about it in this Mikroniek article. The next research stage will focus on bringing stability performance within specification throughout the entire range. Finally, the sensor’s ability to also measure wafer tilt (Rx and Ry), for counteracting tilt-dependent wafer height measurement errors, will be investigated. (Image courtesy of Hittech Multin)