Strasbaugh

Other

Lam Research Corporation

Stephan H Wolf

David G Halley

John M Boyd

Randolph E Treur

Gregory L Barbour

Benjamin C Smedley

An wafer polishing pad assembly for use in CMP includes an optical sensor for sensing reflectivity of the wafer during polishing, and produces a corresponding signal, and transmits the signal from the rotating pad to a stationary portion of the assembly. The signal is transmitting off the pad through non-contact couplings such inductive coupling or optical couplings after being converted into signal formats enabling non-contact transmission.

Endpoint detection system for wafer polishing

An apparatus is disclosed which improves the optical monitoring of semi-conductor wafers undergoing chemical mechanical planarization (CMP). The apparatus consists of two assemblies. The first is a fiber optical wave-guide assembly installed within the polishing pad during the pad's construction. This assembly forms an integrated optical waveguide originating from the center of rotation of the polishing pad and terminating at a location within the wafer track. The second is a vacuum-attached hub containing optical and electronic devices, which couples light into the waveguide integrated into the polishing pad, provides light coupling to the center of rotation of the polishing pad, provides means for converting the received light into a signal that is transmitted to the CMP tool control system, and also has provision to prevent polishing slurry from coming in contact with the optical and electronic components. Alternately the vacuum-attached hub may contain optical devices only, which couples light into the waveguide integrated into the polishing pad and transmits the received light to the CMP tool control system.

Optical coupler hub for chemical-mechanical-planarization polishing pads with an integrated optical waveguide

An apparatus is disclosed which improves the optical monitoring of semi-conductor wafers undergoing chemical mechanical planarization. The apparatus consists of two assemblies. Firstly, a fiber optical wave-guide assembly installed within the polishing pad during the pad's construction. This assembly forms an integrated optical waveguide originating from the center of rotation of the polishing pad and terminating at a location within the wafer track. Secondly, a vacuum hub, tube, and angular encoder assembly, which provides light coupling to the center of rotation of the polishing pad and also provides resolution of the angular position and speed of the polishing pad, polishing table, and optical waveguide.

Fiber optical sensor embedded into the polishing pad for in-situ, real-time, monitoring of thin films during the chemical mechanical planarization process

An optical endpoint system for a CMP system with a viewport located off-center on the platen, said view port being adjustable in height so that the window of the viewport can be made flush with the top of the polishing pad.

Optical view port for chemical mechanical planarization endpoint detection

An optical sensor that includes a light source and a detector is located within a cavity in a polishing pad so as to face the surface that is being polished. Light from the light source is reflected from the surface being polished and the reflected light is detected by the detector. The electrical signal produced by the detector is conducted to a hub located at the central aperture of the polishing pad. The disposable polishing pad is removably connected, both mechanically and electrically to the hub. The hub contains electronic circuitry that is concerned with supplying power to the optical sensor and with transmitting the electrical signal to a non-rotating station. Several techniques are described for accomplishing these tasks. The system permits continuous monitoring of an optical characteristic of a surface that is being polished, even while the polishing machine is in operation, and permits the end point of the polishing process to be determined.

Growing community of inventors

Los Osos, CA, United States of America

Stephan H Wolf