International Business Machines Corporation

Gary Joseph Beardsley

Cuc Kim Huynh

David Louis Walker

Theodore Gerard Van Kessel

Timothy Scott Bullard

Steven J Messier

Michael P McMahon

Zhong X He

In a fabrication process, photoresist is disposed over a semiconductor substrate ( ), covering a front surface ( ) of the substrate ( ) and filling trenches ( ) therein. The photoresist is planarized in chemical mechanical polishing to achieve a uniform thickness throughout the substrate ( ). An anisotropic etching process partially removes the photoresist in the trenches ( ), thereby creating recesses in the trenches ( ). Because the thickness of the photoresist is uniform throughout the substrate ( ) before the etching process, the depths of the recesses in different trenches ( ) are substantially equal to each other. A uniform recess depth throughout the substrate ( ) is thereby achieved. The uniform recess depth facilitates in ensuring the semiconductor devices fabricated on the substrate ( ) to have consistent parameters, characteristics, and performances.

Method for homogenizing device parameters through photoresist planarization

A method of detecting the presence of a brush used in a semiconductor wafer cleaner for post-CMP processing is described. Semiconductor wafers are loaded into the wet environment of the wafer cleaner, affixed to a rotatable fixture and rotated at high speed. The rotatable fixture is effectuated by a servo motor linked to a servo controller and a torque monitor. A first torque on the rotating wafer is calculated prior to the start of the brush cleaning cycle. During the brush cleaning cycle, as the brush within the brush cleaner contacts the rotating wafer, the torque on the wafer increases and a second torque is calculated. If, during the brush cleaning cycle, the second torque calculation is substantially equal to the first torque calculation, the brush cleaner is not contacting the wafer and cleaning has not progressed. A tool user can be notified to reaffix the brush within the cleaner. When the second torque calculation is greater than expected, the tool user can be notified that the brush downforce has been improperly set. Inadequate removal of CMP residue is detected before entire wafer lots have passed through an ineffective brush cleaning cycle prior to an inspection point.

Post CMP cleaning method using a brush cleaner with torque monitor

A polishing apparatus for polishing a substrate. The polishing apparatus has a slurry delivery system for delivering slurry to the apparatus; a porous polishing pad having an upper surface at which the substrate is polished; and a rotating platen upon which the porous pad lies. The rotating platen has a recess which has a first portion in communication with the delivery means for delivering slurry into the first portion. The recess further has a second portion extending under the polishing pad. Slurry is delivered from the first portion to the second portion and to the upper surface of the pad where it aids in the polishing of the substrate. Preferably, the first portion of the recess is situated such that the slurry delivered to the top surface returns to the first portion for removal or reuse due to the rotational force of the rotating platen.

CMP apparatus with built-in slurry distribution and removal

An apparatus for and method of detecting the presence of a brush used in a semiconductor wafer cleaner for post-CMP processing is described. Semiconductor wafers are loaded into the wet environment of the wafer cleaner, affixed to a rotatable fixture and rotated at high speed. The rotatable fixture is effectuated by a servo motor linked to a servo controller and a torque monitor. A first torque on the rotating wafer is calculated prior to the start of the brush cleaning cycle. During the brush cleaning cycle, as the brush within the brush cleaner contacts the rotating wafer, the torque on the wafer increases and a second torque is calculated. If, during the brush cleaning cycle, the second torque calculation is substantially equal to the first torque calculation, the brush cleaner is not contacting the wafer and cleaning has not progressed. A tool user can be notified to reaffix the brush within the cleaner. When the second torque calculation is greater than expected, the tool user can be notified that the brush downforce has been improperly set. Inadequate removal of CMP residue is detected before entire wafer lots have passed through an ineffective brush cleaning cycle prior to an inspection point.

Post CMP clean brush with torque monitor

A non-motorized polishing pad conditioner and cleaner having a free-wheeling conditioner head with a plurality of channels to direct the flow of a cleansing fluid; a hollow shaft connected to a fluid source; and a conditioning pad to facilitate loosening the debris found on a polishing pad wherein the pad conditioner and cleaner is self-propelled upon contact with a rotating polishing pad. A cantilever may be used to attach the conditioner and cleaner adjacent to the polishing apparatus. The cantilever may contain a motorized element for extending and retracting the conditioner and cleaner over the radius of a polishing pad such that the entire surface of the polishing pad may be conditioned and cleaned. A method of conditioning and cleaning a polishing pad while simultaneously polishing a silicon wafer is also described.

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Underhill, VT, United States of America

Gary Joseph Beardsley