title: In situ dissolution or deposition of Ytterbium (Yb) metal in microhotplate wells for a miniaturized atomic clock.
abstract: Current atomic clocks are burdened by size, weight, power and portability limitations to satisfy a broad range of potential applications. One critical need in the fabrication of a miniaturized atomic clock is small, low-power metallic sources. Exploiting the relatively high vapor pressure of ytterbium (Yb) and its dissolution in anhydrous ammonia, we report two independent techniques for depositing Yb inside a well micromachined into a microhotplate. Subsequent in situ evaporation of Yb from the microhotplate well serves as a low-power metallic source suitable for atomic clocks. The deposition and evaporation of Yb were confirmed using a variety of physicochemical techniques including quartz crystal microbalance, scanning electron microscopy, energy dispersive X-ray spectroscopy, and laser fluorescence. We also describe the fabrication of the microhotplate device, an integral component of our Yb-based miniature atomic clock. The Yb deposition/evaporation on a microhotplate well is thus useful as a low power Yb source during the fabrication of a miniaturized atomic clock, and this technique could be used for other applications requiring a vapor of a metal that has a moderate vapor pressure.
authors.affiliation: Microsystems-Enabled Detection, Sandia National Laboratories, 1515 Eubank Blvd, Albuquerque, New Mexico 87185, USA. rpmangi@sandia.gov
authors.forename: Ronald P
authors.initials: RP
authors.lastname: Manginell
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Moorman
authors.forename: John M
authors.initials: JM
authors.lastname: Anderson
authors.forename: George R
authors.initials: GR
authors.lastname: Burns
authors.forename: Komandoor E
authors.initials: KE
authors.lastname: Achyuthan
authors.forename: David R
authors.initials: DR
authors.lastname: Wheeler
authors.forename: Peter D D
authors.initials: PD
authors.lastname: Schwindt