Abstract: An automatic machine and an automatic method for grinding the perimetric edge of rectangular or nonrectangular of glass sheets arranged substantially vertically, comprising at least one conveyor and at least one workhead provided with an abrasive tool for grinding the glass sheet at its edge, following its perimetric profile by way of the relative action of movement of the glass sheet and movement of the at least one workhead. During grinding, the glass sheet is no longer supported and moved by the conveyor but by at least one carriage, to which the glass sheet is coupled by way of at least one sucker.

Abstract: A backgrinding machine 10 of a semiconductor wafer W includes: a table 13 set on the working plane of a mount 11; a multiple number of holding jigs 20 arranged via check tables 15 on table 13; a grinding machine 30 for performing a grinding process of the rear side of semiconductor wafer W held by holding jig 20; and a washing device 40 for ground semiconductor wafers W. Each holding jig 20 is constructed of a concave 22 depressed on the surface of a base plate 21, a multiple number of supporting projections 23 projectively arrayed on the bottom surface of concave 22, a deformable contact film 24, covering the concave 22, being supported by the multiple supporting projections 23, for detachably holding semiconductor wafer W in close contact with it; and an exhaust path 25 for conducting air from the concave 22 covered by contact film 24 to the outside.

Abstract: The present invention relates to a substrate holding apparatus for holding and pressing a substrate against a polishing surface. The substrate holding apparatus includes a top ring body for holding the substrate, an elastic pad for contacting the substrate, and a support member for supporting the elastic pad. The substrate holding apparatus further includes a contact member mounted on a lower surface of the support member and disposed in a space formed by the elastic pad and the support member. The contact member has an elastic membrane for contacting the elastic pad. A first pressure chamber is defined in the contact member, and a second pressure chamber is defined outside of the contact member. The substrate holding apparatus also includes a fluid source for independently supplying a fluid into, or creating a vacuum in, the first pressure chamber and the second pressure chamber.

Abstract: [Problem] A non-contact type suction holding apparatus capable of reliably holding a plate-shaped member without damaging its surface by suction-holding the plate-shaped member with a portion except for its peripheral portion (main portion) in a non-contact state in which it is floated off the suction table is provided. [Means for Solving Problems] In a non-contact type suction holding apparatus 1 according to the present invention, Bernoulli suction means 10 generating negative pressure by blowout of air (gas) is disposed in a suction table 2, the wafer W is held by the Bernoulli suction means 10 in a state in which a portion except for a peripheral portion of the wafer (plate-shaped member) W of which under-surface peripheral edge portion is supported on the suction table 2 is floated off the suction table 2, and the wafer is suction-held without contact with the suction table 2.

Abstract: A method of transferring a wafer is disclosed. The method comprises providing a pedestal and at least one spray orifice extending through the pedestal; disposing a wafer above the pedestal using a first robot, wherein the wafer has a first surface and a second surface, the first surface faces the pedestal, a fluid is sprayed onto the first surface simultaneously to avoid a contact of the first surface with the pedestal, and the fluid contains a charge-forming chemical substance dissolved therein; and taking the wafer using a robot for delivery. Due to the charge-forming chemical substance dissolved in the fluid, the waterfall effect to cause discharge damage on the wafer is avoided in the spraying of the fluid.

Abstract: A polishing apparatus has a top ring configured to hold a semiconductor wafer on a substrate holding surface, and a pushser configured to deliver the semiconductor wafer to the top ring and receive the semiconductor wafer from the top ring. The pushser includes a push stage having a substrate placement surface on which the semiconductor wafer is placed and an air cylinder configured to vertically move the push stage. The pushser also includes a high-pressure fluid port configured to eject a high-pressure fluid toward the semiconductor wafer.

Abstract: A polishing head is tested in a test station having a pedestal for supporting a test wafer and a controllable pedestal actuator to move a pedestal central wafer support surface and a test wafer toward the polishing head. In another aspect of the present description, the test wafer may be positioned using a positioner having a first plurality of test wafer engagement members positioned around the pedestal central wafer support surface. In another aspect, the wafer position may have a second plurality of test wafer engagement members positioned around an outer wafer support surface disposed around the pedestal central wafer support surface and adapted to support a test wafer. The second plurality of test wafer engagement members may be distributed about a second circumference of the ring member, the second circumference having a wider diameter than the first circumference. Additional embodiments and aspects are described and claimed.

Abstract: An edge control system for deployment on a CMP carrier head comprising a bladder and a carrier head housing having a passage extending therethrough. The bladder includes a flexible diaphragm and is coupled to the carrier head housing. The edge control system comprises first and second annular ribs, each of which comprises a first end portion sealingly coupled to the carrier head housing, a second end portion coupled to the diaphragm, and a strain relief member substantially intermediate the first end portion and the second end portion. A plenum is substantially defined by the first and second annular ribs and the carrier head housing. The passage is fluidly coupled to the plenum to permit the pressurization of the plenum, and the strain relief member promotes the extension of the first and second annular ribs away from the carrier head housing when the plenum is pressurized.

Abstract: The present invention is a chuck having a vacuum groove that is capable of holding a wafer as the chuck rotates on a spindle. As the chuck rotates the air pressure above the center of the wafer is reduced. In order to reduce the bowing of the wafer that can result from this low pressure area above the wafer, the present invention introduces venturi holes in the chuck which reduces the air pressure in the area below the wafer. In order to prevent the air pressure in the area below the wafer from decreasing too far, the present invention uses air inlet holes to balance the affect of the venturi holes in order to substantially balance the air pressure above and below the wafer which results in significantly less bowing of the wafer when compared to conventional systems. The present invention accomplishes this without requiring sensors or other active measuring devices to help reduce the bowing of the wafer.

Abstract: A contact planarization apparatus includes a lower membrane assembly, an upper membrane assembly, a differential pressure assembly, and a curing or reflowing assembly. The lower membrane assembly supports a substrate to be planarized and biases it toward the upper membrane assembly under the influence of the pressure differential assembly. The upper membrane assembly planarizes the coating on the substrate under the influence of the differential pressure assembly and includes a flexible sheet which is supported above the substrate stage and below the curing or reflowing assembly via a vacuum force applied by the differential pressure assembly. The differential pressure assembly moves the lower and upper membrane assemblies relative to one another to planarize the coating on the substrate entirely through the application of vacuum and pressure forces.

Abstract: A fixture for grinding machines includes a first base (10) and a second base (20). The first base has a first surface (12) which defines a first holding groove (11). The first base defines a plurality of first suction holes (13) on the first surface. The second base has a second surface (22) which defines a second holding groove (21) corresponding to the first holding groove. The second base defines a plurality of second suction holes (23) on the second surface.

Abstract: A polishing apparatus that employs a polishing media retention arrangement to prevent slippage or wrinkles in the polishing media during polishing. The polishing media is drawn against a support surface by a vacuum applied between the polishing media and the support surface. Also, a porous layer may be placed between the polishing media and the support surface to form dimples in the polishing media upon the application of vacuum. An alternative arrangement draws the polishing media against a carrier and the substrate to be polished.

Abstract: A carrier head that has a base assembly, a retaining ring assembly, a carrier ring, and a flexible membrane is described. A retaining ring assembly has a flexible membrane shaped to provide an annular chamber and an annular retaining ring, wherein annular concentric projections of the flexible membrane are sized to fit into annular concentric recesses of the annular retaining ring.

Abstract: A polishing head and method for handling and polishing semiconductor wafers uses a base structure with at least one recess region and an outer flexible membrane that can conform to the at least one recess region to form at least one depression to hold a semiconductor wafer onto the outer flexible membrane when suction is applied to the at least one depression.

Abstract: A substrate holding apparatus is for holding a substrate such as a semiconductor wafer in a polishing apparatus for polishing the substrate to a flat finish. The substrate holding apparatus comprises a vertically movable member, and an elastic member for defining a chamber. The elastic member comprises a contact portion which is brought into contact with the substrate, and a circumferential wall extending upwardly from the contact portion and connected to the vertically movable member. The circumferential wall has a stretchable and contractible portion which is stretchable and contractible vertically.

Abstract: A carrier head for supporting a workpiece is provided. The carrier head comprises a mount plate having an aperture therethrough, and a clamp ring having a foot portion and a first leg portion extending therefrom. The first leg portion extends through the aperture, and the foot portion abuts the mount plate proximate the aperture. A flexible bladder has first and second ribs that are received between the mount plate and the foot portion. An annular fastener is removably coupled to the leg portion, and engages the mount plate to cause the first and second ribs to be sealingly secured between the mount plate and the foot portion.

Abstract: An apparatus for holding a plurality of lenses, including: a block having a mounting surface; a cavity defined in the block at the mounting surface; and a through hole defined in the block, the through hole being in communication with the cavity, wherein the mounting surface is configured for mounting of the lenses thereon whereby the lenses cooperatively substantially close the cavity at the mounting surface. Because of the cavity has a vacuum therein, the lenses can be retainable attached on the mounting surface by means of the vacuum.

Abstract: The present invention relates to a substrate holding apparatus for holding a substrate such as a semiconductor wafer in a polishing apparatus for polishing the substrate to a flat finish. The substrate holding apparatus according to the present invention comprises a top ring body having a receiving space therein, and a vertically movable member which is vertically movable within the receiving space in the top ring body. An abutment member having an elastic membrane is attached to a lower surface of the vertically movable member. The elastic membrane of the abutment member comprises an abutment portion, having a flange projecting outwardly, brought into direct or indirect contact with the substrate, and a connecting portion extending upwardly from a base portion of the flange of the abutment portion and being connected to the vertically movable member. The connecting portion is made of a material having a flexibility higher than that of material of the abutment portion.

Abstract: Disclosed herein is a moving head for a semiconductor wafer polishing apparatus. The semiconductor wafer polishing apparatus has a table on which a polishing pad is formed, and the moving head mounted via a support unit to hold a wafer relative to a polishing surface of the table. In this case, the moving head includes a sensing means having a load cell and a piezoelectric sensor to measure pressing force and frictional force acting on the wafer provided in the moving head. The present invention relates to the polishing of a semiconductor wafer material from which an integrated circuit is made.

Abstract: A method and apparatus for planarizing a microelectronic substrate. In one embodiment, one surface of the microelectronic substrate is engaged with a planarizing pad and the opposite surface of the microelectronic substrate is positioned proximate to a substrate support. A bearing liquid, such as a planarizing liquid, is directed toward the second surface of the microelectronic substrate to form a liquid bearing between the substrate and substrate support. The microelectronic substrate can precess relative the substrate support as the substrate support moves relative to the planarizing pad. The substrate support can include a sensor to determine a characteristic, such as a thickness, of the liquid bearing. In another embodiment, a portion of the liquid bearing can be removed from the second surface of the microelectronic substrate to control the thickness of the liquid bearing and/or to remove particulate matter from the liquid bearing.

Abstract: A differential pressure application apparatus is configured to apply different amounts of pressure to different locations of a substrate, such as a semiconductor device structure. The apparatus may be used during polishing or planarization processes. The apparatus includes physically discrete pressurization structures that may be moved independently from one another. An actuator may control the amount of force or pressure applied by each pressurization structure to the surface of the substrate. Systems including the pressure application apparatus, as well as differential pressure application methods and polishing methods are also disclosed.

Abstract: A pedestal pad (workpiece supporting table pad) is arranged on the top of a pedestal (workpiece supporting table) for temporarily placing and holding a pre-polished or post-polished wafer (workpiece). This pedestal pad is formed of resin, and at least a surface of the pedestal pad which comes into contact with the wafer is non-absorbable to a fluid. The tissue of the pedestal pad is dense and smooth, and does not have any cavity, such as fine holes, which holds the fluid.

Abstract: A draining device for removing processing water attached to a lens includes: a first lens holding shaft to which a cup attached to a refractive surface of the lens as a processing jig can be fitted; and a rotating unit which rotates the first lens holding shaft to remove the water by centrifugal force.

Abstract: A fixture for grinding machines includes a first base (10) and a second base (20). The first base defines a first workpiece holding groove (11 ) therein, a first side surface (12) is formed corresponding to the first workpiece holding groove, and the first base defines a plurality of first attracting holes (13) on the first side surface. The second base defines a second workpiece holding groove (21) corresponding to the first workpiece holding groove therein, a second side surface (22) is formed corresponding to the second workpiece holding groove, and the second base defines a plurality of second attracting holes (23) on the second side surface.

Abstract: A thin wafer carrying device includes a laminated board made of layers of compound material so that the thin wafer is put on the circular board. The compound material includes reinforcement material and high-polymer resin. A metal film good in electric conductivity is coated to the compound material. The compound material has been used in printed circuit boards. The carrying device includes a plurality of tiny holes and a vacuum system located beneath the circular board. The thin wafer is attracted on the carrying device by the method of vacuum and is convenient to be tested, processed and transported.

Abstract: A system for chemical mechanical polishing having a carrier head with pressurizeable chambers that can be configured into pressure zones is described. The system includes a carrier head with a membrane for contacting a substrate during polishing. Pressurizeable chambers behind the membrane are in communication with pressure inputs. The pressure inputs can each supply a different pressure to the pressurizeable chambers. Some of the pressurizeable chambers can be in communication with more than one pressure input. Zones of pressure can be arranged, where each zone includes one or more pressurizeable chambers. The zones can be configurable by altering the pressurizeable chambers that make up each zone.

Abstract: A semiconductor element holding apparatus includes a collet for suctioning a semiconductor element by negative pressure to hold the semiconductor element. The collet has a protrusion formed at the semiconductor element-holding surface thereof, and the protrusion is provided with a plurality of suction holes. The suction holes are opened to the semiconductor element-holding surface. The surface of the semiconductor element is held by the semiconductor element-holding surface of the protrusion of the collet.

Abstract: A cutting apparatus jets, at a high pressure, water containing abrasive grains to cut a workpiece along cutting lines extending in intersecting directions. The cutting apparatus includes: a fixing table fixing the workpiece; groove portions provided in the fixing table at respective positions below the cutting lines; protruded portions provided in regions of the fixing table other than regions where the groove portions are provided, in a manner that the workpiece contacts the protruded portions; support portions provided to connect the protruded portions substantially in parallel with cutting lines extending the Y direction along the groove portions; a frame portion provided to connect the support portions to each other in at least a part of an outer periphery of the fixing table; and protection members attachably and detachably provided to cover the support portions.

Abstract: Disclosed is a device for grinding a liquid crystal display panel improving the efficiency of using equipment by independently operating first and second grinding units for grinding the unit liquid crystal display panel. The present invention includes a first grinding unit grinding edges of short or long sides of the unit liquid crystal display panel in a normal mode and a second grinding unit grinding the edges of the short or long sides of the unit liquid crystal display panel that are not ground by the first grinding unit in the normal mode or grinding the edges of the long and short sides of the unit liquid crystal display panel in an emergency mode.

Abstract: A grinder designed to provide an automatic grinding operation for the manufacture of a semiconductor device wafer. The grinder includes a base, a rotatable index table mounted to the base, and a grinding wheel assembly including a grinding wheel for grinding a flat surface on the wafer. The index table includes a wafer holder for receiving and holding the wafer. A dressing station, including a dressing element, is positioned adjacent to the index table for dressing the grinding wheel. The dressing station is rotatable between a first position and a second position where the grinding wheel is dressed by the dressing element.

Abstract: Planarizing machines, carrier heads for planarizing machines and methods for planarizing microelectronic-device substrate assemblies in mechanical or chemical-mechanical planarizing processes. In one embodiment of the invention, a carrier head includes a backing plate, a bladder attached to the backing plate, and a retaining ring extending around the backing plate. The backing plate has a perimeter edge, a first surface, and a second surface opposite the first surface. The second surface of the backing plate can have a perimeter region extending inwardly from the perimeter edge and an interior region extending inwardly from the perimeter region. The perimeter region, for example, can have a curved section extending inwardly from the perimeter edge of the backing plate or from a flat rim at the perimeter edge. The curved section can curve toward and/or away from the first surface to influence the edge pressure exerted against the substrate assembly during planarization.

Abstract: A cup attaching apparatus for attaching a cup, used during processing of an eye glass lens, to the lens, the apparatus includes: a placing portion onto which the lens is placed; a holding portion for detachably holding the cup; a supporting portion for supporting the holding portion; a moving mechanism for moving the supporting portion in an optical axis direction of the placed lens; and a pressure regulating mechanism for preventing a cup attaching force from exceeding a predetermined pressure.

Abstract: Apparatus for chemical mechanical polishing are disclosed. A disclosed apparatus includes a polishing station having a polishing pad, a gas supplier to generate pressurized gas to press a wafer toward the polishing pad, and a polishing head assembly including a planar member having a plurality of fine holes in communication with the gas supplier and a membrane to press the wafer toward the polishing pad due to the pressurized gas received through the plurality of fine holes, wherein the plurality of fine holes are arranged to rotate at different radii of rotation when the planar member rotates.

Abstract: An apparatus and method are described herein which help prevent particles and other contaminants that are generated when an edge of a glass sheet is processed from contaminating or damaging the glass sheet. The apparatus includes an encapsulation device and a processing device. The encapsulation device is capable of supporting two surfaces of a glass sheet. And, the processing device is capable of processing (e.g., cutting, scribing, grinding or polishing) the edge that is adjacent to the supported two surfaces of the glass sheet which are located on a first side of the encapsulation device. The encapsulation device is also capable of substantially preventing particles and other contaminants that are generated when the processing device processes the edge of the glass sheet from reaching the two surfaces of the glass sheet which are located on a second side of the encapsulation device.

Abstract: An apparatus and method are described herein which help prevent particles and other contaminants that are generated when an edge of a glass sheet is processed from contaminating or damaging the glass sheet. The apparatus includes an encapsulation device and a processing device. The encapsulation device is capable of supporting two surfaces of a glass sheet. And, the processing device is capable of processing (e.g., cutting, scribing, grinding or polishing) the edge that is adjacent to the supported two surfaces of the glass sheet which are located on a first side of the encapsulation device. The encapsulation device is also capable of substantially preventing particles and other contaminants that are generated when the processing device processes the edge of the glass sheet from reaching the two surfaces of the glass sheet which are located on a second side of the encapsulation device.

Abstract: A semiconductor device has an alignment mark which can be recognized by a conventional wafer prober. A redistribution layer connects electrodes of the semiconductor device to electrode pads located in predetermined positions of the redistribution layer. Metal posts configured to be provided with external connection electrodes are formed on the electrode pads of the redistribution layer. A mark member made of the same material as the metal posts is formed on the redistribution layer. The mark member serves as an alignment mark located in a predetermined positional relationship with the metal posts.

Abstract: A draining device for removing processing water attached to a lens includes: a first lens holding shaft to which a cup attached to a refractive surface of the lens as a processing jig can be fitted; and a rotating unit which rotates the first lens holding shaft to remove the water by centrifugal force.

Abstract: A tool for gripping ophthalmic lenses including a vacuum gripper, a shaft associated with said vacuum gripper, the shaft having two ends and being slidably attached at one end thereof to a support structure, a resilient member which biases the vacuum gripper in a direction away from said support structure and a locking member which locks the shaft in a desired position during a lens gripping operation. Another embodiment of the present invention includes a lens hold down mechanism for holding lenses in a lens tray. Another embodiment of the present invention includes an electronic communications scheme for a robotic manufacturing operation. Another embodiment of the present invention includes an ophthalmic lens manufacturing cell layout wherein ophthalmic edging machines have an opening that faces away from a robotic arm. Another embodiment of the present invention includes an arrangement for holding an ophthalmic edging machine within an ophthalmic manufacturing cell.

Abstract: The present invention relates to a substrate holding apparatus for holding a substrate to be polished and pressing the substrate against a polishing surface. The substrate holding apparatus comprises a top ring body for holding a substrate, an elastic pad for being brought into contact with the substrate, and a support member for supporting the elastic pad. The substrate holding apparatus further comprises a contact member mounted on a lower surface of the support member and disposed in a space formed by the elastic pad and the support member. The contact member has an elastic membrane for being brought into contact with the elastic pad. A first pressure chamber is defined in the contact member, and a second pressure chamber is defined outside of the contact member. The substrate holding apparatus further comprises a fluid source for independently supplying a fluid into, or creating a vacuum in, the first pressure chamber and the second pressure chamber.

Abstract: Techniques for removing a substrate from a polishing pad are described. A substrate is pulled away from the polishing pad such that the edges of the substrate are pulled away from the polishing pad before the center of the substrate is pulled from the polishing pad.

Abstract: A membrane for vacuum suction of a silicon water typically used inside a polishing head. The membrane has a flat main body and a plurality of protrusions each having a spiny shape over the surface of the flat main body. The protrusions are formed in positions that correspond to the holes of a supporting multiple-hole panel. The protrusions on the flat main body lower the suction pressure between the wafer and the membrane somewhat so that wafer unloading failure is minimized.

Abstract: A differential pressure application apparatus is configured to apply different amounts of pressure to different locations of a substrate, such as a semiconductor device structure. The apparatus may be used during polishing or planarization processes. The apparatus includes pressurization structures that may be moved independently from one another. An actuator may control the amount of force or pressure applied by each pressurization structure to the surface of the substrate. Systems including the pressure application apparatus, as well as differential pressure application methods and polishing methods are also disclosed.

Abstract: Techniques for singulating a substrate into a plurality of component parts is disclosed. The singulation techniques include generating a jet stream in order to cut through large components so as to produce smaller components. The techniques are particularly suitable for singulating surface mount devices such as chip scale packages, ball grid arrays (BGA), flip chips, lead less packages (QFN) and the like. The techniques are also suitable for singulating photonic devices.

Abstract: A semiconductor wafer may be secured to a wafer support system by causing a supported surface of the semiconductor wafer to be at a lower gas pressure than an exposed surface of the semiconductor wafer.

Abstract: Planarizing machines, carrier heads for planarizing machines and methods for planarizing microelectronic-device substrate assemblies in mechanical or chemical-mechanical planarizing processes. In one embodiment of the invention, a carrier head includes a backing plate, a bladder attached to the backing plate, and a retaining ring extending around the backing plate. The backing plate has a perimeter edge, a first surface, and a second surface opposite the first surface. The second surface of the backing plate can have a perimeter region extending inwardly from the perimeter edge and an interior region extending inwardly from the perimeter region. The perimeter region, for example, can have a curved section extending inwardly from the perimeter edge of the backing plate or from a flat rim at the perimeter edge. The curved section can curve toward and/or away from the first surface to influence the edge pressure exerted against the substrate assembly during planarization.

Abstract: A compact pinlifter assembly is fitted in a substantially enclosed cavity within a wafer chuck such that an overall outside shape of the wafer chuck remains highly unaffected. The pinlifter assembly includes wedge guides providing a movement path in a wedge angle relative to the wafer holding face. A pin actuator is driven along the wedge guides transforming its movement along the wedge guides into a vertical movement of the lifting pins perpendicularly sliding between the cavity and the wafer holding face. The combination of wedge guides and pin actuator takes advantage of the relatively large lateral dimensions of the wafer chuck to move the pin actuator between end positions that are in a distance multiple of the pin lifters movement. Due to the wedge angle, the actuators comparatively large scale movement is transformed in a highly precise, smooth and balanced movement of the pin lifters.

Abstract: The present invention relates to a substrate holding apparatus for holding a substrate such as a semiconductor wafer in a polishing apparatus for polishing the substrate to a flat finish. The substrate holding apparatus according to the present invention comprises a top ring body having a receiving space therein, and a vertically movable member which is vertically movable within the receiving space in the top ring body. An abutment member having an elastic membrane is attached to a lower surface of the vertically movable member. The elastic membrane of the abutment member comprises an abutment portion, having a flange projecting outwardly, brought into direct or indirect contact with the substrate, and a connecting portion extending upwardly from a base portion of the flange of the abutment portion and being connected to the vertically movable member. The connecting portion is made of a material having a flexibility higher than that of material of the abutment portion.

Abstract: A polishing head of a wafer polishing apparatus includes a body, a center supporter installed in a center of the body, a perforated plate including an upper plate and a lower plate that is disposed below the center supporter and has a plurality of thru-holes, a membrane covering the perforated plate, and a moving member for moving the lower plate up and down. By moving the lower plate up and down, the polishing head forcibly recovers an elasticity of the membrane (especially at an edge portion of the membrane).

Abstract: The present invention provides an apparatus and method for protecting a work piece during surface processing. The apparatus employs a protective material to protect a wafer during backside grinding. The apparatus can further include a vacuum chuck that allows the passage of a vacuum signal, a frame holding the protective material, a frame holder to hold the frame, and a fastening arrangement to fasten the frame holder to the chuck adjacent a support surface. The method provided by the invention can include providing a vacuum chuck, placing a protective material in contact with the chuck, placing a wafer in contact with the protective material, applying a vacuum signal securing the wafer with the chuck, and grinding the backside surface of the wafer.

Abstract: A polishing apparatus for polishing a workpiece such as a semiconductor wafer has a turntable with a polishing surface, and a top ring for holding a workpiece and pressing the workpiece against the polishing surface under a first pressing. The polishing apparatus has a pressurized fluid source for supplying pressurized fluid, and a plurality of openings provided in the holding surface of the top ring for ejecting the pressurized fluid supplied from the pressurized fluid source. A plurality of areas each having the openings are defined on the holding surface so that the pressurized fluid is selectively ejectable from the openings in the respective areas.