Device and method for collecting and measuring chemical samples on pad surface in CMP
AssigneeMicron Technology, Inc.
InventorMichael J. Joslyn
Life of this patent
Estimating the term…
Abstract
A chemical collection assembly and a method for using the assembly such that a chemical-mechanical polishing (CMP) pad used in the manufacture of semiconductor wafers can be assessed for cleanliness. The method involves delivering solvent from the assembly's reservoir to an enclosed volume over the CMP pad. The solvent then brings contaminants imbedded on the CMP pad into solution. This solution is then drawn back up from the enclosed volume wherefrom a sample of the solution can be taken. That sample is then analyzed for the level of contaminants present therein, and the analysis is compared to a pre-determined level of cleanliness to determine whether the CMP pad should or should not continue to be used for semiconductor wafer manufacturing.
Claims28
A method of determining the cleanliness of a CMP pad comprising:
- positioning a retaining structure on a first surface of the CMP pad so as to define a controlled space;
- injecting a controlled volume of solution onto the CMP pad within the controlled space, wherein the solution is selected to dissolve contaminants on the CMP pad;
- extracting the solution with the dissolved contaminants from the controlled space adjacent the CMP pad;
- sampling the extracted solution to determine the quantity of dissolved contaminants on the CMP pad;
- and
- determining, based on the sampling of the extracted solution, whether the CMP pad meets a pre-selected cleanliness threshold.
An assembly for obtaining a sample indicative of the cleanliness of a CMP pad having a first surface, the assembly comprising:
- a retaining structure that is positionable adjacent the first surface so as to define an enclosed volume adjacent the first surface of the CMP pad;
- a reservoir containing a sampling solution;
- a delivery mechanism for delivering the sampling solution to the enclosed volume such that the sampling solution absorbs contaminants on the first surface of the CMP pad;
- an extraction mechanism that extracts the sampling solution from the enclosed volume such that the extracted sampling solution contains contaminants of the first surface of the CMP pad so that the sampling solution can be evaluated to determine the cleanliness of the first surface of the CMP pad.
An assembly for assessing the cleanliness of a CMP pad comprising:
- a retaining structure that is adapted to be positioned adjacent a surface of the CMP pad, wherein the retaining structure defines an enclosed volume that retains fluid within the enclosed volume adjacent the surface of the pad;
- and
- a pipette that stores a cleaning solution, wherein the cleaning solution in the pipette can be injected onto the surface of the CMP pad within the enclosed volume and wherein the cleaning solution can be extracted from the enclosed volume for subsequent analysis to determine the level of contaminants to thereby ascertain whether the CMP pad is suitable for continued use.
A system for evaluating the cleanliness of a surface of a CMP pad, the system comprising:
- a delivery system for delivering cleaning solution to the surface of the CMP pad;
- a retaining structure that is positionable with respect to the surface of the CMP pad so as to define an area on the surface of the CMP pad into which the delivery system positions the cleaning solution;
- a recovery system that recovers cleaning solution from the area on the CMP pad for subsequent analysis;
- and
- a controller that sends signals to the delivery system and the recovery system so as to induce delivery and recovery of the cleaning solution.
Dependencies are inferred from the claim text.