Apparatus for flash vaporization delivery of reagents

Claims

What is claimed is:

1. A liquid delivery system for delivery of an initially liquid reagent in vaporized form to a chemical vapor deposition reactor arranged in vapor-receiving relationship to the liquid delivery system, said liquid delivery system comprising:

(a) an elongate fluid flow passage defining a longitudinal axis and bounded by an enclosing wall to define a cross-section of the fluid flow passage transverse to the longitudinal axis;

(b) a thin flat porous vaporization element,

(i) having pores in the range of 2 to 200 micrometers,

(ii) having a surface to volume ratio of at least 4, and

(iii) positioned in the fluid flow passage transverse to the longitudinal axis and extending over the cross-section of the fluid flow passage to an outer periphery at the enclosing wall;

(c) means for heating the thin flat porous vaporization element to elevated temperature for vaporization of said liquid reagent;

(d) passage means for delivering a stream of said liquid reagent onto the surface of said porous vaporization element so that the reagent liquid wets the surface of the porous vaporization element in a thin layer of the liquid reagent and is vaporized on said surface when heated by said heating means (c); and

(e) means for discharging vapor formed by vaporization of reagent liquid on the porous vaporization element, from the fluid flow passage for passage to the chemical vapor deposition reactor.

2. A liquid delivery system according to claim 1, wherein the passage means for delivering a stream of said liquid reagent onto the surface of said porous vaporization element comprise a liquid reagent delivery conduit longitudinally extending along the elongate fluid flow passage and terminating at the surface of the porous vaporization element.

3. A liquid delivery system according to claim 1, wherein the porous vaporization element comprises a sintered disk formed of a material selected from the group consisting of metal, glass and ceramics.

4. Apparatus for forming films or layers on a substrate from a source reagent vapor derived from an initially liquid reagent, comprising:

a chemical vapor deposition reactor; and

a liquid deliver system arranged in vapor feeding relationship to the chemical vapor deposition reactor, for delivery of the initially liquid reagent in vaporized form to the chemical vapor deposition reactor.

said liquid delivery system comprising:

(a) an elongate fluid flow passage defining a longitudinal axis and bounded by an enclosing wall to define a cross-section of the fluid flow passage transverse to the longitudinal axis;

(b) a thin flat porous vaporization element,