Abstract: A substarate processing apparatus capable of reducing the capacity of a space in an internal chamber. The internal chamber is housed in a space in an external chamber. A gas supply unit supplies a process gas into the space in the internal chamber. The space in the external chamber is under a reduced pressure or filled with an inert gas. An enclosure being movable and included in the internal chamber defines the space in the internal chamber with a stage heater included in the internal chamber. When a wafer is transferred in and out by a transfer arm used to transfer the wafer, the enclosure exits out of a motion range within which the transfer arm can move.

Abstract: An apparatus for etching an edge of a wafer includes a chamber, a chuck disposed inside the chamber upon which the wafer is disposed, a plate spaced apart from the wafer and disposed above the wafer, and an edge ring formed along the edge of the wafer and combined with an outer periphery of the plate, wherein the edge ring comprises a ring base spaced a distance apart from the wafer to form a parallel plane with respect to the wafer, and a first ring protrusion protruding from the ring base to insulate the edge of the wafer from a central region of the wafer.

Abstract: A substrate processing system includes a pedestal including a substrate supporting surface having a diameter that is greater than a diameter of a substrate to be processed by the substrate processing system. A first surface extends a first distance above the substrate supporting surface in a direction substantially perpendicular to the substrate supporting surface. The first distance is greater than or equal to one-half of a thickness of the substrate. A gap is defined between the first surface and an outer diameter of the substrate. A second surface extends a second distance from the first surface at an angle with respect to the first surface. The angle is greater than zero and less than ninety degrees. A third surface extends from the second surface and is substantially parallel to the substrate supporting surface. An etchant source directs etchant onto the substrate to etch the substrate.

Abstract: Apparatus and methods for diagnosing status of a consumable part of a plasma reaction chamber, the consumable part including at least one conductive element embedded therein. The method includes the steps of: coupling the conductive element to a power supply so that a bias potential relative to the ground is applied to the conductive element; exposing the consumable part to plasma erosion until the conductive element draws a current from the plasma upon exposure of the conductive element to the plasma; measuring the current; and evaluating a degree of erosion of the consumable part due to the plasma based on the measured current.

Abstract: The invention provides a removable first edge ring configured for pin and recess/slot coupling with a second edge ring disposed on the substrate support. In one embodiment, a first edge ring includes a plurality of pins, and a second edge ring includes one or more alignment recesses and one or more alignment slots for mating engagement with the pins. Each of the alignment recesses and alignment slots are at least as wide as the corresponding pins, and each of the alignment slots extends in the radial direction a length that is sufficient to compensate for the difference in thermal expansion between the first edge ring and the second edge ring.

Abstract: A base material is placed on a base material placement face of a base material placement table. An inductively coupled plasma torch unit is structured with a cylindrical chamber structured with a cylinder made of an insulating material and provided with a rectangular slit-like plasma jet port, and lids closing opposing ends of the cylinder, a gas jet port that supplies gas into the cylindrical chamber, and a solenoid coil that generates a high frequency electromagnetic field in the cylindrical chamber. By a high frequency power supply supplying a high frequency power to the solenoid coil, plasma is generated in the cylindrical chamber, and the plasma is emitted from the plasma jet port to the base material. While relatively shifting the plasma torch unit and the base material placement table, a base material surface can be subjected to heat treatment.

Abstract: Plasma confinement ring assemblies are provided that include confinement rings adapted to reach sufficiently high temperatures on plasma-exposed surfaces of the rings to avoid polymer deposition on those surfaces. The plasma confinement rings include thermal chokes adapted to localize heating at selected portions of the rings that include the plasma exposed surfaces. The thermal chokes reduce heat conduction from those portions to other portions of the rings, which causes selected portions of the rings to reach desired temperatures during plasma processing.

Abstract: A semiconductor device manufacturing apparatus includes a chamber in which a wafer is loaded; a first gas supply unit for supplying a process gas into the chamber; a gas exhaust unit for exhausting a gas from the chamber; a wafer support member on which the wafer is placed; a ring on which the wafer support member is placed; a rotation drive control unit connected to the ring to rotate the wafer; a heater disposed in the ring and comprising a heater element for heating the wafer to a predetermined temperature and including an SiC layer on at least a surface, and a heater electrode portion molded integrally with a heater element and including an SiC layer on at least a surface; and a second gas supply unit for supplying an SiC source gas into the ring.

Abstract: The present invention provides methods and an apparatus for controlling and modifying line width roughness (LWR) of a photoresist layer with enhanced electron spinning control. In one embodiment, an apparatus for controlling a line width roughness of a photoresist layer disposed on a substrate includes a processing chamber having a chamber body having a top wall, side wall and a bottom wall defining an interior processing region, a support pedestal disposed in the interior processing region of the processing chamber, and a plasma generator source disposed in the processing chamber operable to provide predominantly an electron beam source to the interior processing region.

Abstract: An apparatus for the plasma treatment of molds (2), in particular for contact lens molds, comprises a treatment chamber (50), in which a first electrode (51) is arranged facing a carrier (1;4) for carrying the molds (2) to be treated. The carrier (1;4) forms the second electrode (52) and comprises a first metal plate (10;40) having holes (100;400) therein and a second metal plate (11;41) which is arranged spaced apart from the first metal plate (10;40), and which is connected to the first metal plate (10;40) in an electrically conductive manner (12,13;43). The molds (2) are arranged on the second metal plate (11;41) with their molding surfaces (210) facing towards the first electrode (51) and are exposable to plasma through the holes (100;400) in the first metal plate (10;40).

Abstract: Provided is a substrate treating apparatus, which includes a process chamber having an inner space, a substrate support part disposed within the process chamber, and supporting a substrate, a gas supply part supplying a process gas into the process chamber, an antenna configured to supply high frequency power into the process chamber to excite the process gas within the process chamber, and a driving part varying a size of the antenna.

Abstract: Various embodiments of an apparatus for holding and processing semiconductor workpieces are provided. In one aspect, an apparatus is provided that includes a first base, a second base and three elongated members coupled to and between the first base and the second base. The three elongated members are spatially arranged so that a semiconductor workpiece may be positioned therebetween. Each of the elongated members has a first lateral edge, a second lateral edge and at least one radially inwardly projecting member. The at least one radially inwardly projecting member has a third lateral edge, a fourth lateral edge and an upper surface for receiving a portion of the semiconductor workpiece and a lower surface. The third lateral edge is displaced laterally inward from the first lateral edge and the fourth lateral edge is displaced laterally inward from the second lateral edge.

Abstract: A susceptor and a semiconductor manufacturing apparatus including the same are provided. A wafer is loaded on a susceptor and the susceptor includes at least one pocket whose bottom surface is inclined. The semiconductor manufacturing apparatus includes a reaction chamber, a heating unit that generates heat in the reaction chamber, a susceptor on which a wafer is loaded and that includes at least one pocket whose bottom surface is inclined, and a rotation shaft coupled with the susceptor.

Abstract: Apparatus configured for the fabrication of three-dimensional integrated devices and three-dimensional integrated devices fabricated therefrom are described. A device side of a donor wafer is coated with a polymer film and exposure of a substrate side to an oxidizing plasma creates a continuous SiO2 film. Portions of the substrate side are selectively coated with a polymer film and etching of uncoated areas removes at least a substantial portion of the crystalline substrate. A plasma etch tool etches a crystalline substrate to within a pre-determined thickness. The silicon portions of the substrate side are etched by exposure to TMAH. After etching, the donor semiconductor wafer is supported by portions of the substrate that were not etched. The supporting structure allows flexing of the donor semiconductor wafer within the etched areas to enable conformality and reliable bonding to the device surfaces of an acceptor wafer to form a three dimensional integrated device.

Abstract: A process plasma chamber for processing a wafer may include a chamber body for processing the wafer, a wafer chuck for positioning the wafer within the chamber body and a plasma body being generated by RF power in the chamber body. The wafer chuck may position the wafer downwards and above the plasma body. The chamber body may include a showerhead positioned below the plasma body. The chamber body may include a first top electrode for receiving RF power. The chamber body may include a second top electrode for receiving RF power.

Abstract: Provided is a substrate dechucking system of a plasma processing chamber adapted to remove a substrate from an ESC with reduction in voltage potential spike during dechucking of the substrate.

Abstract: A semiconductor substrate processing system includes a substrate support defined to support a substrate in exposure to a processing region. The system also includes a first plasma chamber defined to generate a first plasma and supply reactive constituents of the first plasma to the processing region. The system also includes a second plasma chamber defined to generate a second plasma and supply reactive constituents of the second plasma to the processing region. The first and second plasma chambers are defined to be independently controlled.

Abstract: In a substrate processing apparatus, a process vessel is configured to accommodate and process a substrate held at a horizontal position. A gas introduction port is installed at a periphery of a first side of the process vessel and configured to introduce gas into the process vessel from a lateral direction of the substrate. A gas exhaust port is installed at a second side of the process vessel which is opposite to the first side, and is configured to exhaust gas inside the process vessel from a lateral direction of the substrate. A slope part is installed between the gas introduction port and the gas exhaust port inside the process vessel, and is configured to guide a flow path of the gas introduced into the process vessel.

Abstract: A gas chamber contains upper and lower chamber bodies forming a cavity, a heating chuck for a wafer, a remote gas source, and an exhaust unit. Gas is injected into the cavity through channels in an injector. Each channel has sections that are bent with respect to each other at a sufficient angle to substantially eliminate entering light rays entering the channel from exiting the channel without reflection. The channels have funnel-shaped nozzles at end points proximate to the chuck. The injector also has thermal expansion relief slots and small gaps between the injector and mating surfaces of the chamber and gas source. The temperature of the injector is controlled by a cooling liquid in cooling channels and electrical heaters in receptacles of the injector. The upper chamber body is funnel-shaped and curves downward at an end of the upper chamber body proximate to the chuck.

Abstract: A system for planarizing a semiconductor device includes a holder component for holding the substrate. The substrate has at least one opening therein, and each opening defines a lower portion and an upper portion. A resist applicator applies a layer of resist over the substrate, such that the resist layer covers the lower and upper portions. An etching component etches back the resist layer to expose the upper portion of the at least one opening. The resist applicator and the etching component repeat the steps of applying and etching, respectively, to remove a predetermined amount below the upper portion. A deposition component deposits an insulating layer over the substrate. A planarizing component planarizes the insulating layer until the upper portion of the at least one opening is exposed.

Abstract: Vacuum processing chambers having provisions for improved electrical contact to substrate carrier. Specific embodiments provide a plasma processing chamber having a pedestal for supporting the carrier, and a plurality of fixed posts and resilient contacts are distributed over the area of the pedestal. The fixed posts provide physical support for the carrier, while the resilient contacts provide reliable and repeatable multi-point electrical contact to the carrier.

Abstract: A substrate etching apparatus includes: a cassette to receive a substrate that has finished a previous process, and transfer the substrate; a first robot to take the substrate out of the cassette; a second robot to receive the substrate from the first robot and move the substrate mounted thereon vertically up and down; an etching cassette comprising a support to support the substrate and a holder to fix the substrate loaded from the second robot; a cassette fixing unit to fix at least one or more etching cassettes and being rotated at a pre-set angle to allow the substrate to be disposed perpendicular to the ground; and an etching unit to etch the substrate disposed perpendicular to the ground by the cassette fixing unit.

Abstract: Provided is a spin head for supporting and rotating a substrate. The spin head includes a body, chuck pins disposed at the body and movable between supporting positions and rest positions, and a chuck pin moving unit configured to move the chuck pins straight. The chuck pins supports a substrate at the supporting positions and provides a substrate loading/unloading space at the rest position. The chuck pin moving unit includes movable rods fixed to the chuck pins, a rotatable cam including protrusions on an outer surface thereof so as to move the chuck pins from the supporting positions to the rest positions, and chuck pin return units respectively applying forces to the movable rods so as to move the chuck pins individually from the rest positions to the supporting positions. The chuck pin moving unit further includes contact maintaining members.

Abstract: A plasma processing method for performing a plasma process on a substrate to be processed by making a plasma act thereon includes the following sequential steps of making a plasma weaker than one used in the plasma process act on the substrate, applying a DC voltage to an electrostatic chuck for attracting and holding the substrate while the weak plasma acts on the substrate, extinguishing the weak plasma, and performing the plasma process. Further, a plasma processing apparatus includes a plasma processing mechanism for performing a plasma process on a substrate to be processed, and a controller for controlling the plasma processing mechanism to thereby perform the plasma processing method.

Abstract: A high throughput chemical treatment system for processing a plurality of substrates is described. The chemical treatment system is configured to chemically treat a plurality of substrates in a dry, non-plasma environment. A substrate support in the chemical treatment system is configured to support a plurality of substrates.

Abstract: A plasma processing chamber has a lower liner with an integrated flow equalizer. In an etching process, the processing gases may be unevenly drawn from the processing chamber which may cause an uneven etching of the substrate. The integrated flow equalizer is configured to equalize the flow of the processing gases evacuated from the chamber via the lower liner.

Abstract: A plasma processing apparatus including a chamber having an inner wall with a protective film thereon and a sample stage disposed in the chamber in which plasma is generated by supplying high-frequency wave energy to processing gas to conduct plasma processing for a sample on the sample stage using the plasma. The apparatus includes a control device which determines, based on monitor values of a wafer attracting current monitor (Ip) to monitor a current supplied from a wafer attracting power source, an impedance monitor (Zp) to monitor plasma impedance viewed from a plasma generating power source, and an impedance monitor (Zb) to monitor a plasma impedance viewed from a bias power supply, presence or absence of occurrence of an associated one of abnormal discharge in inner parts, deterioration in insulation of an insulating film of a wafer attracting electrode, and abnormal injection in a gas injection plate.

Abstract: In a plasma processing apparatus, a ceiling electrode plate provided to face a substrate holding stage via a process space contacts and is supported by an electrode support by interposing a cooling plate, and a heat-transfer sheet is provided in a contact surface between the ceiling electrode plate and the cooling plate. The heat-transfer sheet has thermal conductivity of 0.5 to 2.0 W/m·K. The heat-transfer sheet is provided of a heat-resistant adhesive agent or a rubber including silicon, or the heat-transfer sheet is formed of a ceramic filler including oxide, nitride, or carbide. The ceramic filler of 25 to 60 volume % is contained in the heat-resistant adhesive agent or the rubber. A thickness of the heat-transfer sheet is in a range between 30 and 80 ?m, and the heat-transfer sheet is not provided in a predetermined area around gas holes of the ceiling electrode plate.

Abstract: A substrate processing apparatus capable of improving a processing controllability in an etching process is provided. The substrate processing apparatus (10) includes a depressurized processing room (11); a susceptor (12) that is provided in the processing room (11) and configured to mount a wafer (W) thereon; a HF high frequency power supply (18) configured to apply a high frequency voltage for plasma generation to the susceptor (12); a LF high frequency power supply (20) configured to apply a high frequency voltage for a bias voltage generation to the susceptor (12); and a DC voltage applying unit (23) configured to apply a DC voltage of a rectangle-shaped wave to the susceptor (12).

Abstract: Aspects of the present disclosure may include an apparatus for enclosing a thin wafer to prevent damage during an on-going manufacture of integrated circuit chip(s) on or in the thin wafer, and methods of utilizing the apparatus. The apparatus may include a lower support assembly and an upper retainer assembly which retains a thin wafer therebetween, wherein the lower support assembly and the upper retainer assembly may be coupled together by a magnetic attractive force.

Abstract: In accordance with one embodiment of the present disclosure, an assembly is provided comprising a multi-component electrode and a peripherally engaging electrode carrier. The peripherally engaging electrode carrier comprises a carrier frame and a plurality of reciprocating electrode supports. The multi-component electrode is positioned in the electrode accommodating aperture of the carrier frame. The backing plate of the electrode comprises a plurality of mounting recesses formed about its periphery. The reciprocating electrode supports can be reciprocated into and out of the mounting recesses. Additional embodiments of broader and narrower scope are contemplated.

Abstract: A process for treating a target region of a component surface with a treatment fluid including: a) determining an amount of treatment fluid required to treat the target region; b) feeding the determined amount of treatment fluid to a treatment device; c) continuously circulating the treatment fluid through an applicator of the treatment device whilst applying the applicator to the target region; and d) discarding the treatment fluid once the target region of the component surface has been treated. An apparatus for treating a target region of a component surface with a treatment fluid is also disclosed and which includes: a treatment fluid reservoir; a treatment device, operable to receive treatment fluid from the treatment fluid reservoir and to apply treatment fluid to the component; a holding fixture for supporting the component; and a sealable enclosure containing the treatment fluid reservoir, the treatment device and the holding fixture.

Abstract: The present invention provides a method for plasma dicing a substrate. The method comprising providing a process chamber having a wall; providing a plasma source adjacent to the wall of the process chamber; providing a work piece support within the process chamber; placing the substrate onto a support film on a frame to form a work piece work piece; loading the work piece onto the work piece support; providing a cover ring disposed above the work piece; generating a plasma through the plasma source; and etching the work piece through the generated plasma.

Abstract: The present invention herein provides a shower head whose temperature can be controlled in consideration of the film-forming conditions selected and a thin film-manufacturing device which permits the stable and continuous formation of thin films including only a trace amount of particles while reproducing a good film thickness distribution and compositional distribution, and a high film-forming rate and which is excellent in the productivity and the mass-producing ability as well as a method for the preparation of such a film.

Abstract: A method of preventing arcing during bevel edge etching a semiconductor substrate with a plasma in a bevel etcher in which the semiconductor substrate is supported on a semiconductor substrate support comprises bevel edge etching the semiconductor substrate with the plasma in the bevel etcher while evacuating the bevel etcher to a pressure of 3 to 100 Torr while maintaining RF voltage seen at the wafer at a low enough value to avoid arcing.

Abstract: A substrate processing method is used for a substrate processing system having a substrate processing device and a substrate transfer device. The substrate processing method includes a substrate transfer step of transferring a substrate and a substrate processing step of performing a predetermined process on the substrate. The substrate transfer step and the substrate processing step include a plurality of operations, and at least two operations among the plurality of the operations are performed simultaneously. Preferably, the substrate processing device includes an accommodating chamber, a mounting table placed in the accommodating chamber to be mounted thereon the substrate, and a heat transfer gas supply line for supplying a heat transfer gas to a space between the substrate mounted on the mounting table and the mounting table.

Abstract: In a transport device for elongated substrates, especially in hot processes, which includes an essentially rectangular frame, formed by longitudinal and transverse spars connected to each other, in which at least three transverse spars are provided between two longitudinal spars, at least one transverse spar is made from a material, whose heat expansion coefficient differs from the heat expansion coefficient of the material of the other transverse spars or/and at least one transverse spar is connected force-free to at least one transverse support or/and at least one transverse spar is formed from an open profile.

Abstract: A vapor phase deposition apparatus includes: a chamber, a supply unit configured to supply a raw gas into the chamber, a support table disposed in the chamber and configured to support a substrate in the chamber, a rotatable bladed wheel configured to have a plurality of blades, to be arranged to surround the support table, and to discharge the raw gas from above the substrate, and a exhaust unit configured to exhaust the raw gas discharged by the bladed wheel after a vapor phase deposition reaction from the chamber.

Abstract: A surface activation device comprises a holding compartment, a nozzle support, and a sealing assembly. The holding compartment defines a receiving chamber and defining a plurality of recesses for holding workpieces therein. The nozzle support is rotatably received in the receiving chamber and comprises an outer barrel, an inner barrel is received in the outer barrel, and at least one ultraviolet (UV) lamp is embedded in the outer barrel. The outer barrel and the inner barrel cooperatively define a first chamber therebetween, and the inner barrel defines a second chamber therein. The sealing assembly seals the first chamber and the second chamber, and comprises at least one first inlet tube communicated with the first chamber and at least one second inlet tube communicated with the second chamber.

Abstract: Provided is a spin head for supporting a substrate. The spin head includes a rotatable body, and chuck pins protruding upward from the body and configured to support an edge of a substrate placed at the body when the body is rotated. Each of the chuck pins includes a vertical rod vertically disposed at the body, and a support rod extending from a side of the vertical rod and configured to make contact with the edge of the substrate placed at the body when the body is rotated. When the substrate is rotated, the vertical rod is spaced apart from the edge of the substrate. The contact portion includes a streamlined side surface. The support rod includes a contact portion. The contact portion tapers toward the end of the support rod when viewed from the top of the support rod.

Abstract: A mechanism for adjusting an orientation of an electrode in a plasma processing chamber is disclosed. The plasma processing chamber may be utilized to process at least a substrate, which may be inserted into the plasma processing chamber in an insertion direction. The mechanism may include a support plate disposed outside a chamber wall of the plasma processing chamber and pivoted relative to the chamber wall. The support plate may have a first thread. The mechanism may also include an adjustment screw having a second thread that engages the first thread. Turning the adjustment screw may cause translation of a portion of the support plate relative to the adjustment screw. The translation of the portion of the support plate may cause rotation of the support plate relative to the chamber wall, thereby rotating the electrode with respect to an axis that is orthogonal to the insertion direction.

Abstract: According to one embodiment, a plasma processing apparatus that includes a process target holding portion and a plasma generating unit in a chamber, and processes a process target by using generated plasma is provided. An yttrium oxide film is formed on an inner wall of the chamber and a surface of a structural member in the chamber on a generation region side of the plasma. The yttrium oxide film includes yttrium oxide particles, has a film thickness of 10 ?m or more and 200 ?m or less, has a film density of 90% or more, and is such that yttrium oxide particles, which are present in a unit area 20 ?m×20 ?m and whose grain boundary is confirmable, are 0 to 80% in area ratio.

Abstract: A plasma source includes upper and lower portions. In a first aspect, an electrical power source supplies greater power to the upper portion than to the lower portion. In a second aspect, the plasma source includes three or more power couplers that are spaced apart vertically, wherein the number of plasma power couplers in the upper portion is greater than the number of plasma power couplers in the lower portion. The upper and lower portions of the plasma source can be defined as respectively above and below a horizontal geometric plane that bisects the vertical height of the plasma source. Alternatively, the upper and lower portions can be defined as respectively above and below a horizontal geometric plane that bisects the combined area of first and second workpiece positions.

Abstract: Systems, methods and apparatus for regulating ion energies in a plasma chamber are disclosed. An exemplary method includes placing a substrate in a plasma chamber, forming a plasma in the plasma chamber via a remotely generated ionizing electromagnetic field that extends into the plasma chamber from a remote projected source, controllably switching power to the substrate so as to apply a periodic voltage function to the substrate, and modulating, over multiple cycles of the periodic voltage function, the periodic voltage function responsive to a desired distribution of energies of ions at the surface of the substrate so as to effectuate the desired distribution of ion energies on a time-averaged basis.

Abstract: The present invention generally includes a shadow frame with alignment inserts that may permit the shadow frame to be properly aligned on the susceptor. The shadow frame may have one or more alignment inserts. The alignment inserts may be coupled to a cavity formed in the bottom surface of the shadow frame. The alignment inserts may be shaped to receive an alignment button that may be present on the susceptor. Thus, as the susceptor raises to the processing position and retrieves the shadow frame, the shadow frame may align properly on the susceptor.

Abstract: There is provided a substrate support device capable of preventing powder dust from being produced. A thermoconductive intermediate member is interposed between a base table and a substrate support table and has a communication aperture path for communicating the aperture path of the base table with the aperture path of the substrate support table. An elastic member such as bellows tube is disposed in the communication aperture path of the thermoconductive intermediate member, for insulating the thermoconductive intermediate member from the inert gas which flows through the communication aperture path.

Abstract: A seal-protected perimeter partition valve apparatus defines a vacuum and pressure sealed space within a larger space confining a substrate processing chamber with optimized geometry, minimized footprint, and 360° substrate accessibility. A compact perimeter partitioned assembly with seal protected perimeter partition valve and internally contained substrate placement member further provides processing system modularity and substantially minimized system footprint.

Abstract: A diameter of a mounting unit of the stage of an ashing processing apparatus is less than a diameter of a mounting unit of the stage of an etching processing apparatus, and the diameter of the mounting unit of the stage of the etching processing apparatus is less than a diameter of an objective item.

Abstract: The following description relates to a plasma processing apparatus and a method thereof. The plasma processing apparatus comprises a first plasma chamber having a first plasma discharge space, a first plasma source for supplying a first activation energy to the first plasma discharge space within the first plasma chamber, a second plasma chamber which is connected to the first plasma chamber and has a second discharge space, and a second plasma source for supplying a second activation energy for inducing inductive coupled plasma to the second plasma discharge space within the second plasma chamber.

Abstract: A substrate supporting apparatus includes a plate member of an aluminum alloy having a flat upper surface, bottomed pits formed in the plate member, and spacer members held in the pits, individually. The spacer members are sapphire spheres. The diameter of each spacer member is a little smaller than that of each pit. The upper end of each spacer member projects from the upper surface of the plate member. A spot facing is formed in a region that includes the open edge portion of the pit. A bending portion which is obtained by plastically deforming the open edge portion of the pit toward the spacer member is formed on a bottom surface of the spot facing. A V-shaped groove is formed behind the bending portion.