Method and appartus for subliming precursors

Abstract

An improved method and apparatus are provided for subliming solid precursors, and especially organometallic precursors, for use in a chemical vapor deposition (CVD) process. The sublimation apparatus includes a sealed vessel having a vacuum chamber. A quantity of the solid precursor is mixed with a loosely packed particulate material, such as ceramic beads, placed within the vacuum chamber. The vacuum chamber and particulate material are heated. A supply of a carrier gas is directed through the particulate material (particularly through pockets formed in the particulate material) to sublime the precursor which coats the individual particles of particulate material. By agitating the particulate material, a relatively constant sublimation area is maintained. Agitation of the particulate material may be with a mechanical stirrer or by directing an a.c. field through a piezoelectric particulate material.

Dependencies are inferred from the claim text.