Lam Research Corporation

Damon Vincent Williams

Miguel Angel Saldana

Aleksander Owczarz

Yehiel Gotkis

Rodney C Kistler

David J Hemker

Bruno Morel

John Boyd

David Wei

Glenn W Travis

CMP systems and methods implement instructions for moving a polishing pad relative to a wafer and a retainer ring and for applying pressure for CMP operations. Feedback of polishing pad position is coordinated with determinations of desired inputs of variable forces by which changing areas of the wafer, a pad conditioning puck, and the retainer ring are separately urged into contact with the polishing pad so that the pressure on each such area is separately controlled. Processing workload is evaluated according to criteria related to the characteristics of the instructions. If none of the criteria is exceeded, a central CMP processor is used for the processing. If any of the criteria is exceeded, the force determinations are made separately from the central CMP processor by a force controller, and the central processor manages data transfer to the force controller.

Polishing apparatus and methods having high processing workload for controlling polishing pressure applied by polishing head

A CMP system accurately measures eccentric forces applied to carriers for wafer or polishing pad conditioning pucks. An initial coaxial relationship between wafer axis of rotation and a carrier axis is maintained during application of the eccentric force, such that a sensor may measure the eccentric forces. Such initial coaxial relationship is maintained by a linear bearing assembly mounted between the carrier and the sensor. The linear bearing assembly is provided as an array of separate linear bearing assemblies, and may be assembled with a retainer ring in conjunction with a motor for moving the ring relative to the wafer mounted on the carrier so that an exposed surface of the wafer and a surface of the retainer ring to be engaged by the polishing pad are coplanar during the polishing operation.

Apparatus for controlling retaining ring and wafer head tilt for chemical mechanical polishing

In chemical mechanical polishing apparatus, a wafer carrier plate is provided with a cavity for reception of a sensor positioned very close to a wafer to be polished. Energy resulting from contact between a polishing pad and an exposed surface of the wafer is transmitted only a very short distance to the sensor and is sensed by the sensor, providing data as to the nature of properties of the exposed surface of the wafer, and of transitions of those properties. Correlation methods provide graphs relating sensed energy to the surface properties, and to the transitions. The correlation graphs provide process status data for process control.

Apparatus and methods for detecting transitions of wafer surface properties in chemical mechanical polishing for process status and control

In chemical mechanical polishing, a wafer carrier plate is provided with a cavity for reception of a sensor positioned very close to a wafer to be polished. Energy resulting from contact between a polishing pad and an exposed surface of the wafer is transmitted only a very short distance to the sensor and is sensed by the sensor, providing data as to the nature of properties of the exposed surface of the wafer, and of transitions of those properties. Correlation methods provide graphs relating sensed energy to the surface properties, and to the transitions. The correlation graphs provide process status data for process control.

Methods for detecting transitions of wafer surface properties in chemical mechanical polishing for process status and control

CMP methods reduce a cause of differences between an edge profile of a chemical mechanical polished edge of a wafer and a center profile of a chemical mechanical polished central portion of the wafer within the edge. The wafer is mounted on a carrier surface of a wafer carrier so that a wafer axis of rotation is gimballed for universal movement relative to a spindle axis of rotation of a wafer spindle. An operation using a retainer ring limits wafer movement on the carrier surface perpendicular to the wafer axis. Another operation limits a direction of permitted movement between the wafer carrier and the retainer ring to only movement parallel to the wafer axis, so that a wafer plane and a retainer ing may be co-planar.

Methods for aligning a surface of an active retainer ring with a wafer surface for chemical mechanical polishing

CMP systems and methods provide necessary vacuum and pressure to be applied from a vacuum chuck through a carrier film to a wafer without interfering with desired wafer planarization during CMP operations. Prior low polish rate-areas on the wafer may be eliminated from an exposed surface of the wafer by structure to uniformly compress the carrier film in response to a force from the wafer on the carrier film during the CMP operations. A distance between, and diameters of, adjacent holes of the carrier film are reduced, and the locations of the holes are in an array to coordinate with passageways through the vacuum chuck. The structure significantly reduces a maximum value of compression of the carrier film during CMP operations. As a result, during the CMP operations the wafer does not deform in a manner that exactly matches the compression of the carrier film, but remains essentially flat.

Chemical mechanical polishing apparatus and methods with porous vacuum chuck and perforated carrier film

A chemical mechanical planarization (CMP) system having a polishing pad, a carrier body for holding a wafer, a retaining ring, and an active retaining ring support is provided. The active retaining ring is defined by a circular ring having a thickness and a width. The circular ring is defined by an elastomeric material. The circular ring is configured to be placed between the retaining ring and the carrier body. The circular ring has a plurality of voids therein, and the plurality of voids are defined in locations around the circular ring. The circular ring has a compressibility level that is set by the elastomeric material and the plurality of voids.

Active retaining ring support

A CMP system and methods reduce a cause of differences between an edge profile of a chemical mechanical polished edge of a wafer and a center profile of a chemical mechanical polished central portion of the wafer within the edge. The wafer is mounted on a carrier surface of a wafer carrier so that a wafer axis of rotation is gimballed for universal movement relative to a spindle axis of rotation of a wafer spindle. A retainer ring limits wafer movement on the carrier surface perpendicular to the wafer axis. The retainer ring is mounted on and movable relative to the wafer carrier. A linear bearing is configured with a housing and a shaft so that a direction of permitted movement between the wafer carrier and the retainer ring is only movement parallel to the wafer axis, so that a wafer plane and a retainer ing may be co-planar.

Apparatus for aligning a surface of an active retainer ring with a wafer surface for chemical mechanical polishing

A system for rinsing and cleaning a wafer carrier and a semiconductor wafer mounted thereon during a polishing process is provided. The system comprises a head spray assembly that includes a spray nozzle and a spray cavity. At least a part of the head spray assembly is moveably positionable between a park position and a spray position. The spray position is proximate to the wafer carrier such that liquid discharged from the spray nozzle is in liquid communication with the wafer carrier and the semiconductor wafer. The liquid as well as the materials rinsed from the wafer carrier and semiconductor wafer may be retained in the spray cavity and channeled out of the head spray assembly.

System for wafer carrier in-process clean and rinse

A CMP system and methods make repeatable measurements of eccentric forces applied to carriers for wafer or polishing pad conditioning pucks. Force applied to the carrier may be accurately measured even though such force is eccentrically applied to such carrier. The CMP system and method provide the repeatable measurement features while supplying fluids within the carrier to the wafer and to a wafer support without interfering with the polishing operations. Similarly, the CMP system and methods remove fluids from the wafer or puck carrier without interfering with the CMP operations. An initial coaxial relationship between an axis of rotation and a carrier axis is maintained during application of the eccentric force, such that a sensor is enabled to make repeatable measurements, as defined above, of the eccentric forces, and the carrier may be a wafer or a puck carrier. Such initial coaxial relationship is maintained by a linear bearing assembly mounted between the carrier and the sensor, and the carrier may be a wafer or a puck carrier. The linear bearing assembly is provided as an array of separate linear bearing assemblies, wherein each separate linear bearing assembly is dimensioned independently of the diameter, for example, of a wafer or puck carried by the carrier. The linear bearing assembly may be assembled with a retainer ring in conjunction with a motor for moving the ring relative to the wafer mounted on the carrier so that an exposed surface of the wafer and a surface of the retainer ring to be engaged by the polishing pad are coplanar during the polishing operation.

Growing community of inventors

Fremont, CA, United States of America

Damon Vincent Williams