New flash-evaporation feeder for chemical vapor deposition

Abstract
A new device for generation of vapor of solid precursor(s) for the Chemical Vapor Deposition (CVD) process has been designed and tested. Powder of the precursor(s) is kept at room temperature in an inert atmosphere during the deposition and steadily delivered by small portions into an evaporator. Small beads of an inert material are added to the powder in order to dilute the mixture and make the slow powder delivery process more reliable. Flash-evaporation of the precursor(s) from the beads' surface assures controlled and constant in-time composition of the precursor(s) vapor. This facilitates the use of temperature unstable precursors. Simultaneous evaporation of several precursors allows multicomponent films to be easily grown. This process is especially suitable for use of precursors with a big difference in sublimation/evaporation temperatures. The feeder was tested during the CVD of nickel, copper, cobalt, and copper-cobalt thin films. These films were deposited from nickel(II) bisdiethylglyoximate, copper(II) bisdipivaloylmethanate, cobalt(II) bisacetylacetoniminate, and cobalt(II) bis-3,5-dimethylpyrazolylborate complexes. The conditions were optimized for the film growing processes in each case. All films were characterized by X-ray Photoelectron Spectroscopy, X-ray Diffraction and Scanning Electron Microscopy.