A Chip-Scale, Low Cost PVD System

• Published in: Journal of microelectromechanical systems Vol. 29; no. 6; pp. 1547 - 1555
• Main Authors: Barrett, Lawrence K., Lally, Richard W., Fuhr, Nicholas E., Stange, Alexander, Bishop, David J.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.12.2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: evaporation; Evaporators; fab-on-a-chip; Film thickness; film thickness monitor; Lab-on-a-chip; Lithography; Low cost; mass sensor; MEMS; Microelectromechanical systems; Micromechanical devices; Nanostructures; Phase locked loops; phased locked loop; Physical vapor deposition; Physical vapor deposition (PVD); quartz oscillator; Thin films
• ISSN: 1057-7157; 1941-0158
• DOI: 10.1109/JMEMS.2020.3026533

Standard physical vapor deposition systems are large, expensive, and slow. As part of an on-going effort to build a fab-on-a-chip, we have developed a chip-scale, low cost, fast physical vapor deposition system designed to be used with atomic calligraphy or dynamic stencil lithography to direct write nanostructures. The system comprises two MEMS devices: a chip-scale thermal evaporator and a mass sensor that serves as a film thickness monitor. Here, we demonstrate the functionality of both devices by depositing Pb thin-films. The thermal evaporator was made by fabless manufacturing using the SOIMUMPs processs (MEMSCAP, inc). It turns on in 1:46 s and reaches deposition rates as high as 7.2Å s −1 with ~1 mm separation from the target. The mass sensor is a re-purposed quartz oscillator (JTX210) that is commercially available for less than one dollar. Its resolution was measured to be 2.65 fg or 7.79E-5 monolayers of Pb. [2020-0237]