Apparatus and method of detecting a polishing endpoint layer of a semiconductor wafer which includes a metallic reporting substance
First Claim
1. A method of planarizing a semiconductor wafer having a polishing endpoint layer that includes a metallic reporting substance, comprising the steps of:
- polishing a first side of said wafer in order to remove material from said wafer;
utilizing an atomic absorption spectroscopic technique to detect the presence of said metallic reporting substance in said material removed from said wafer; and
terminating said polishing step in response to detecting the presence of said metallic reporting substance.
10 Assignments
0 Petitions
Accused Products
Abstract
A method of planarizing a semiconductor wafer to a distance from a semiconductor substrate of the wafer is disclosed. The method includes the step of forming in the wafer a metallic reporting substance that is at the predetermined distance from the substrate of the wafer. The method also includes the step of polishing a first side of the wafer in order to remove material from the wafer. The method further includes the step of utilizing an atomic absorption spectroscopic technique to detect the presence of the metallic reporting substance in the material removed from the wafer. Moreover, the method includes the step of terminating the polishing step in response to the detection of the metallic reporting substance. An associated apparatus for polishing a semiconductor wafer down to a metallic reporting substance of the wafer is also described.
83 Citations
20 Claims
-
1. A method of planarizing a semiconductor wafer having a polishing endpoint layer that includes a metallic reporting substance, comprising the steps of:
-
polishing a first side of said wafer in order to remove material from said wafer; utilizing an atomic absorption spectroscopic technique to detect the presence of said metallic reporting substance in said material removed from said wafer; and terminating said polishing step in response to detecting the presence of said metallic reporting substance. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A method of planarizing a semiconductor wafer to a distance from a semiconductor substrate of said wafer, comprising the steps of:
-
forming in said wafer a metallic reporting substance that is at said distance from said substrate of said wafer; polishing a first side of said wafer in order to remove material from said wafer; utilizing an atomic absorption spectroscopic technique to detect the presence of said metallic reporting substance in said material removed from said wafer; and terminating said polishing step in response to detection of said metallic reporting substance. - View Dependent Claims (10, 11, 12, 13, 14, 15)
-
-
16. An apparatus for polishing a semiconductor wafer down to a metallic reporting substance of said wafer, said wafer having a first side and a second side, comprising:
-
a polishing platen having a polishing surface; a wafer carrier configured to (i) engage said wafer by said second side of said wafer and (ii) press said first side of said wafer against said polishing surface of said polishing platen; a slurry supply system configured to apply a chemical slurry to said first side of said wafer which (i) facilities removal of said metallic reporting substance from said wafer, and (ii) receives said metallic reporting substance removed from said wafer, wherein said polishing platen and said wafer carrier are configured to rub said first side of said wafer against said polishing surface in the presence of said chemical slurry in order to remove said metallic reporting substance from said wafer; and a polishing endpoint detector that (i) utilizes an atomic absorption spectroscopic technique to detect the presence of said metallic reporting substance in said material removed from said wafer, and (ii) is operable so as to cause said polishing of said wafer to terminate in response to detecting the presence of said metallic reporting substance. - View Dependent Claims (17, 18, 19, 20)
-
Specification