M Cubed Technologies, Inc.

Ii-vi Delaware, Inc.

Other

Zygo Corporation

Edward Gratrix

Brian J Monti

Michael K Aghajanian

Prashant G Karandikar

Derek Rollins

David Casale

Daniel Mastrobattisto

Robert E Klinger

Austin Scott McDannald

William Vance

Prashant Karandikar

William Spitzmacher

A machine featuring a treatment tool that grinds a surface to a desired profile, imparts a desired roughness to that surface, and removes contamination from the surface, the machine configured to control multiple independent input variables simultaneously, the controllable variables selected from the group consisting of (i) velocity, (ii) rotation, and (iii) dither of the treatment tool, and (iv) pressure of the treatment tool against the surface. The machine can move the treatment tool with six degrees of freedom.

Machine for finishing a work piece, and having a highly controllable treatment tool

Diamond-containing articles such as composite materials shaped as some specific article, can be engineered such that bodies that contact the article only contact diamond. In an embodiment, the article may be in the form of equipment for handling semiconductor wafers such as vacuum or electrostatic chucks. In one embodiment, the diamond-containing article can be a composite of diamond particulate reinforcing a Si/SiC body such as reaction-bonded SiC. Lapping the diamond-reinforced RBSC body with progressively finer diamond grit removes some of the SiC/Si matrix material, leaving diamond particles of uniform height 'standing proud' above the rest of the surface of the formed article. Further, if the diamond-containing article is sufficiently electrically conductive, it may be machinable using electrical discharge machining.

Articles having diamond-only contact surfaces

An article includes a ceramic material and features a machined surface that is characteristic of cold ablation laser machining, and the machined surface exhibits no visible oxidation. A laser machining apparatus and technique is based on cold-ablation, but is modified or augmented with an inert assist gas to minimize deleterious surface modifications and mitigate oxide formation associated with laser machining.

Inert gas-assisted laser machining of ceramic-containing articles

A chemical-mechanical polishing/planarization pad conditioner body made from diamond-reinforced reaction bonded silicon carbide, with diamond particles protruding or 'standing proud' of the rest of the surface, and uniformly distributed on the cutting surface. In one embodiment, the diamond particles are approximately uniformly distributed throughout the composite, but in other embodiments they are preferentially located at and near the conditioning surface. The tops of the diamond particles can be engineered to be at a constant elevation (i.e., the conditioner body can be engineered to be very flat). Exemplary shapes of the body may be disc or toroidal. The diamond particles can be made to protrude from the conditioning surface by preferentially eroding the Si/SiC matrix. The eroding may be accomplished by electrical discharge machining or by lapping/polishing with abrasive.

Diamond composite CMP pad conditioner

In a deterministic setting for finishing the support surface of a chuck such as a wafer chuck, the treatment tool may have a contacting surface shaped as a ring, annulus, or toroid, or at least such will be the form of contact when the treatment tool is brought into contact with a flat surface. The treatment tool may have about the same hardness as the work piece (e.g., the wafer chuck) that is being finished. In one embodiment, the treatment tool, or at least the flat contacting surface, is made from silicon carbide (SiC), or contains SiC, for example, in the form of a composite material such as reaction-bonded SiC.

Method for deterministic finishing of a chuck surface

A method for decontaminating support surfaces of a wafer chuck, such as a wafer chuck, entails lightly passing a treatment tool having a nominally flat contacting surface over the regions of the chuck where contaminants are to be removed. The treatment tool and the chuck surface may have about the same hardness. The treatment tool may be minimally constrained so that it may conform to the surface being processed. When the treatment tool is contacted to a flat surface, the locust of contact may be in the form of a circle, ring or annulus. At higher application pressures, the treatment tool will abrade the chuck, which here is to be avoided, or at least minimized. Thus, the instant inventors have discovered that the same treatment tool that is used to engineer the elevation or profile of the surface, and its roughness, at lower application pressures can be used to remove grinding debris and other contaminants from the surface.

Method for removing contamination from a chuck surface

Grinding, lapping and polishing basically work by making scratches in the body being ground, lapped or polished. The scratches typically are linear. The scratches gives rise to a directionality component of friction: the friction coefficient is less in the direction along the scratch than in a direction orthogonal, or across, the scratch. In a wafer handling/chucking situation, one wants the wafer to settle on the chuck, which involves the outer regions of the wafer moving radially with respect to the chuck. One can reduce friction in the radial direction by giving the lapping scratches a preferred orientation, namely, radial. This can be achieved by making the final passes of the lapping tool move predominantly in radial directions.

Wafer chuck featuring reduced friction support surface

A perforated film electrode for a pinned electrostatic chuck that lies below the top surface of the pins in the valleys or interstices between pins, below the elevation of the top surface of the pins, and is attached to the body of the chuck. In one embodiment, the perforated film electrode assembly features a thin film electrode sandwiched between thin sheets of electrically insulating material. The top, outer or exposed surface of the perforated film electrode assembly has a flatness that is maintained within 3 microns. That is, the distance or elevation between the tops of the pins and the top surface of the perforated film unit is maintained within plus or minus 3 microns. A tool for producing a uniform elevation of the top and bottom sheets or layers of electrically insulating material also is taught.

Film electrode for electrostatic chuck

A method for selectively coating the tops of pins of a pin chuck with a high thermal stability material, such as diamond-like carbon (DLC). Non-pin areas ('valleys') of the pin chuck support surface are temporarily covered with glass frit or glass beads during the DLC coating operation. After coating, the glass frit/beads masking material may be removed, leaving the DLC material selectively coating the pin tops. The selective DLC coating avoids the cracking or warping problems due to CTE mismatch when DLC is coated over the entire pin chuck support surface, as the pin chuck material typically is very different from DLC.

Methods for masking a pin chuck, and articles made thereby

In a wafer chuck design featuring pins or 'mesas' making up the support surface, engineering the pins to have an annular shape, or to contain holes or pits, minimizes sticking of the wafer, and improves wafer settling. In another aspect of the invention is a tool and method for imparting or restoring flatness and roughness to a surface, such as the support surface of a wafer chuck. The tool is shaped such that the contact to the surface being treated is a circle or annulus. The treatment method may take place in a dedicated apparatus, or in-situ in semiconductor fabrication apparatus. The tool is smaller than the diameter of the wafer pin chuck, and may be approximate to the spatial frequency of the high spots to be lapped. The movement of the tool relative to the support surface is such that all areas of the support surface may be processed by the tool, or only those areas needing correction.

Wafer pin chuck fabrication and repair

The invention features a method for attaching a surface of a first optical element to a surface of a second optical element. The method includes: providing a bonding glass on at least one of the surfaces, wherein the bonding glass is selected to match the refractive indices of the first and second optical elements at the surfaces over a first range of wavelengths and absorb optical energy to a greater extent than that of the optical elements over a second range of wavelengths different from the first range of wavelengths; positioning the surfaces proximate one another; directing optical energy to the bonding glass through at least one of the optical elements at a wavelength in the second range of wavelengths, wherein the optical energy is sufficient to melt the bonding glass without deforming the optical elements; and allowing the melted bonding glass to solidify and fuse the proximately positioned surfaces.

Growing community of inventors

Monroe, CT, United States of America

Edward Gratrix