Abstract: A filtering device for a gravity-flow liquid treatment system includes a first filter component that can be either exposed or adjacent to a substantially transparent region in at least a portion of a filter housing. The first filter component is capable of providing a visual indication of exposure to at least one contaminant. The contaminants for which the first filter component can indicate exposure include particles, inorganic, and organic contamination. Particle contamination is indicated by a change in color of the first filter component through particle collection. Inorganic and organic contaminants are indicated by reaction with at least one agent capable of undergoing a color-change reaction in response to at least one contaminant.

Abstract: A method of delivering a reagent to a wafer is provided. A solvent is provided. A set of conditions of temperature and pressure is provided to the solvent, which is sufficient to bring the solvent to supercritical conditions. A reagent is provided. A surfactant is provided, where the surfactant has a first moiety with an affinity for the solvent and a second moiety with an affinity for the reagent, where the surfactant increases the concentration of the reagent that may be carried by the solvent. The solvent, surfactant, and reagent are combined to form a solution. The solution is delivered to a supercritical process chamber, wherein a wafer is exposed to the solution in the process chamber.

Abstract: Disclosed formulations of supercritical solutions are useful in wafer cleaning processes. Supercritical solutions of the invention may be categorized by their chemistry, for example, basic, acidic, oxidative, and fluoride chemistries are used. Such solutions may include supercritical carbon dioxide and at least one reagent dissolved therein to facilitate removal of waste material from wafers, particularly for removing photoresist and post-etch residues from low-k materials. This reagent may include an ammonium carbonate or bicarbonate, and combinations of such reagents. The solution may include one or more co-solvents, chelating agents, surfactants, and anti-corrosion agents as well.