Supercritical fluid-based cleaning compositions and methods

Abstract

Compositions and methods employing supercritical fluids, e.g., supercritical carbon dioxide, for removal of unwanted material from microelectronic device structures and process equipment. One composition of such type, having utility for removing flux and solder perform surface films, includes supercritical fluid, e.g., supercritical CO₂, and organic co-solvent, e.g., xylene. Another composition of such type having utility for removal of metals, metal oxides, metal-containing post-etch residues and, CMP particles from semiconductor substrates includes supercritical fluid and at least one β-diketone.

Description

BACKGROUND OF INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to supercritical fluid-based compositions and methods useful in semiconductor manufacturing for the removal of unwanted material from semiconductor manufacturing equipment as well as semiconductor substrates and device structures. [0003] 2. Description of the Related Art [0004] In the field of semiconductor manufacturing, many different types of cleaning reagents are utilized for removing unwanted material from process chambers as well as substrates and microelectronic device structures. Examples include removal of flux employed in connection with bonding of integrated circuitry devices and packages, cleaning of chemical reservoirs for use in deposition operations, and cleaning of substrates and device structures to remove post-etch, lithographic resist residue, and removal of chemical mechanical planerization slurry particulates in deep trench, high aspect ratio structures. [0005] Each of ...

AI Technical Summary

Benefits of technology

[0020] Yet another aspect of the invention relates to a method of making a packaged integrated circuit (IC) product, comprising fabricating an IC chip, affixing the IC chip to packaging structure with an array of solder preform balls in contact with a flux, applying heat to the array

Problems solved by technology

A significant problem with flip-chip bonding is the need to remove all residual flux from the space between the chip and the package, with the difficulty being attributable to the relatively narrow separation of the chip and package, as well as the proximity of the solder balls to each other (in the array of solder bumps that is typically employed for the bonding operation).

This proximity prevents good circulation and removal of conventional cleaning media, such as polar organic solvents, used for removing the residual flux.

Such cleaning processes employ large amounts of organic solvents, producing substantial volumes of organic waste and increasing the cost of the process, due to the necessity of solvent abatement and reclamation operations, to comply with applicable environmental and safety regulations.

These conventional cleaning processes also have an associated deficiency when aqueous rinsing is employed, since any adsorbed water can be difficult to remove from the reservoir.

If remaining in the reservoir as a residue, such adsorbed water can cause degradation of chemical reagents, when the reservoir is refilled with the chemical reagent and returned to active processing service.

The degradation of the chemical reagent in turn may result in the manufactured semiconductor product being de

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