Abstract: Provided are ionic purifiers and methods that are suitable for providing an ultra-high-purity chemical to a semiconductor manufacturing process. The ionic purifiers include a vapor inlet introducing a chemical vapor to be purified into a column. A high-purity water inlet continuously introduces high-purity water into the column. The high-purity water contacts the chemical vapor to be purified, thereby forming a purified chemical vapor and contaminated water. A vapor outlet removes the purified chemical vapor from the column. A liquid outlet removes the contaminated water from the column. The invention has particular applicability in the semiconductor manufacturing industry.

Abstract: Provided is a novel on-site system and method for providing ultra-high-purity nitric acid to a point of use. The system includes a source of nitric acid at a concentration greater than 68 wt %; a reflux distillation column having an inlet in communication with the nitric acid source for introducing nitric acid into the column, a reboiler, and a condensate outlet to provide a flow of nitric acid condensate from the column; a reservoir in communication with the condensate outlet for receiving the flow of nitric acid condensate; and piping for delivering nitric acid from the reservoir to a point of use. The system and method can be used as an on-site subsystem, in a semiconductor device fabrication facility for supplying the nitric acid condensate to points of use in the semiconductor device fabrication facility.

Abstract: The invention relates to an improved method and a novel apparatus for the concentration, separation, and purification of contaminated chemical compounds, wherein the chemical compound is less volatile than the contaminant. The distillation is performed using constant, predetermined distillation parameters.

Abstract: The invention relates to an improved method and a novel apparatus for the concentration, separation, and purification of contaminated chemical compounds, wherein the chemical compound is less volatile than the contaminant. The distillation is performed using constant, predetermined distillation parameters.

Abstract: Method and apparatus for the distillation of liquids which is particularly suited for the removal of soluble impurities and insoluble and non-volatile particles of 10 microns to 0.2 micron or less in size. A substantially elongated distillation chamber having walls equipped with axially disposed concentric boiling rings spaced from the walls near the bottom, and a packing stop, packing redirector rings for condensed vapor, and a reflux condenser in the upper part of the distillation chamber provide, during distillation, a smooth convective upward flow of distilling liquid and vapor proximate the walls and boiling rings and a smooth convective downward flow of distilling liquid and vapor substantially centrally of the distillation chamber.

Abstract: The invention relates to a distillation method and an apparatus for the concentration and purification of water-containing liquid chemicals. The distillation is performed using constant, predetermined distillation parameters.

Abstract: The invention relates to a distillation method and an apparatus for the concentration and purification of water-containing liquid chemicals. The distillation is performed using constant, predetermined distillation parameters.

Abstract: Method for the production of ultrapure sulfuric acid including distillation of sulfuric acid material for the removal of soluble impurities and insoluble and non-volatile particles of 10 microns to 0.2 micron or less in size. Reprocessing is also provided. Distillation takes place in a distillation chamber having walls which are provided with means within the chamber to provide smooth convective upward flow of distilling liquid and vapor proximate the walls and means for smooth convective downward flow substantially centrally of the distillation chamber. Redirection means and packing together with reflux means insure the washing of rising vapor and direct the condensing vapor substantially centrally of the distillation chamber. Ultrapure sulfuric acid is also provided having 5 or less particles per cubic centimeter of a size of 0.5 micron and larger and less than 10 ppb of any specific trace impurity such as cations.

Abstract: An improved wafer cleaning process wherein a novel oxidant solution comprising ultrapure sulfuric acid, peroxydisulfuric acid, and ultrapure water used in a semiconductor wafer cleaning process is continuously withdrawn after use. The withdrawn oxidant is reprocessed continuously by contacting with alumina to remove fluoride ions. Water is continuously separated or stripped from the oxidant solution by heating the solution and bubbling an inert gas therethrough. The separated oxidant is continuously distilled and condensed to form a purified stream of sulfuric acid. The major portion of this stream is continuously returned to the wafer cleaning process. The remaining minor portion is continuously cooled, subjected to analysis for purity, and diluted with ultrapure water prior to electrochemical treatment in the anode compartment of an electrochemical cell. This converts at least a portion of the dilute sulfuric acid to peroxydisulfuric acid.

Abstract: A continuous process and apparatus for the repurification of ultrapure liquids. An oxidant solution comprising ultrapure sulfuric acid, peroxydisulfuric acid, and ultrapure water is continuously withdrawn from a process after use. The withdrawn oxidant is reprocessed continuously by contacting with alumina to remove fluoride ions. Water is continuously separated or stripped from the oxidant solution by heating the solution and bubbling an inert gas therethrough causing the water to vaporize from the solution. The separated oxidant is continuously distilled and condensed to form a purified stream of sulfuric acid. The major portion of this stream is continuously returned to the process. The remaining minor portion is continuously cooled, subjected to analysis for purity, and diluted with ultrapure water. The diluted sulfuric acid is further cooled prior to electrochemical treatment in the anode compartment of an electrochemical cell.