Abstract: 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.

Abstract: Techniques for polishing a wafer (10) include closed-loop control. The wafer can be held by a carrier head (100) having at least one chamber whose pressure is controlled to apply a downward force on the wafer. Thickness-related measurements of the wafer can be obtained during polishing and a thickness profile for the wafer is calculated based on the thickness-related measurements. The calculated thickness profile is compared to a target thickness profile. The pressure in at least one carrier head chamber is adjusted based on results of the comparison. The carrier head chamber pressures can be adjusted to control the amount of downward force applied to the wafer during polishing and/or to control the size of a loading area on the wafer against which the downward force is applied.

Abstract: A continuous CMP process for polishing multiple conductive and non-conductive layers on a semiconductor substrate. The continuous process comprises the steps of: (a) disposing a substrate on a platen; (b) polishing a first layer using both a mechanical means and a chemical means; and (c) polishing a second layer upon adjusting at least one parameter in either the mechanical means, chemical means, or both.

Abstract: A polishing head and a chemical mechanical polishing apparatus having the polishing head including a plate having vacuum holes for transferring vacuum pumping force; a porous film having holes corresponding to the vacuum holes and attached to a lower surface of the plate; a retainer ring attached to the lower surface of the plate at an edge portion thereof and having a sloped surface; a clamp ring attached to the lower surface of the plate adjacent the retainer ring for clamping the retainer ring; an adjusting ring having a sloped surface parallel and in contact with the sloped surface of the retainer ring, the adjusting ring being installed between the retainer ring and the plate; and a diameter adjusting device for adjusting a diameter of the adjusting ring by moving the adjusting ring along the sloped surface of the retainer ring, thereby adjusting a height of the retainer ring.

Abstract: A CMP pad conditioning unit having a new and improved drive transmission for transmitting rotation from a drive motor to a conditioning disk on the pad conditioning unit. The drive transmission includes a rotatable transmission shaft that is drivingly engaged by the drive motor and drivingly engages the conditioning disk. In operation, rotation is transmitted from the drive motor to the conditioning disk through the transmission shaft. The drive transmission is characterized by reliability, longevity and enhanced efficiency in the conditioning of substrate polishing pads.

Abstract: A platen is provided for use in a chemical mechanical planarization (CMP) system. The platen includes at least one fluid output zone having a plurality of fluid outlets, the at least one fluid output zone being disposed below a polishing pad and being capable of providing fluid pressure to the polishing pad. The platen also includes at least one fluid input zone having a plurality of fluid inlets, the at least one fluid input zone being disposed below the polishing pad and being capable of removing the fluid pressure. The platen is capable of managing fluid pressure applied to the polishing pad to achieve a particular polishing profile during a CMP operation.

Abstract: A holder for semiconductor wafers in an apparatus for chemical-mechanical polishing of semiconductor wafers, having a disk-shaped head, a holding plate and a ring-shaped membrane attached to the carrier section and the holding plate which defines a pressure chamber between these components, the bores in the holding plate being connected with the pressure chamber, a contact membrane of elastomeric gas-impermeable material having a peripheral edge which is fixedly connected to a peripheral portion of the holding plate in a gas-tight manner and engages the lower side of the holding plate.

Abstract: A carrier head for chemical mechanical polishing, includes a base, a support structure attached to the base having a surface for contacting a substrate, and a retaining structure attached to the base to prevent the substrate from moving along the surface. The retaining structure and the surface define a cavity for receiving the substrate. The retaining structure includes an upper portion in contact with the base, a lower portion, and a vibration damper separating the upper portion and the lower portion. The vibration damper, the vibration damper includes a material that does not rebound to its original shape when subjected to a deformation.

Abstract: The thickness of a layer on a substrate is measured in-situ during chemical mechanical polishing. A light beam is divided through a window in a polishing pad, and the motion of the polishing pad relative to the substrate causes the light beam to move in a path across the substrate surface. An interference signal produced by the light beam reflecting off the substrate is monitored, and a plurality of intensity measurements are extracted from the interference signal. Each intensity measurement corresponds to a sampling zone in the path across the substrate surface. A radial position is determined for each sampling zone, and the intensity measurements are divided into a plurality of radial ranges according to the radial positions. The layer thickness is computed for each radial range from the intensity measurements associated with that radial range.

Abstract: A polishing apparatus is used for polishing a substrate such as a semiconductor wafer, and has a sensor capable of continuously detecting the thickness of an electrically conductive layer. The polishing apparatus includes a polishing table having a polishing surface, and a top ring for holding and pressing the substrate against the polishing surface to polish the surface of the substrate. A sensor such as an eddy-current sensor is disposed below the polishing surface of the polishing table for measuring the thickness of a conductive layer formed on the surface of the substrate.

Abstract: The present invention is directed to an apparatus and method for flow regulation of planarization fluids to a semiconductor wafer planarization machine. In one embodiment, the regulating system includes a fluid storage tank with an acoustic fluid level sensor. The storage tank is connected to a fluid delivery line that delivers planarization fluid to the storage tank through a flow control valve and delivers a regulated flow of planarization fluid to a planarization machine through a flow sensor. A gas supply system is connected to the storage tank to provide system pressurization. Regulation of the fluid flow is achieved by a control system in which the flow sensor and the acoustic fluid level sensor comprise feedback elements in a closed feedback system to independently control the pressure in the storage tank and the fluid admitted by the control valve. In an alternate embodiment, the fluid level sensor is comprised of capacitive proximity sensors located outside the wall of the storage tank.

Abstract: An apparatus and method for chemical mechanical polishing in which a substrate is pressed against a polishing pad by a carrier head having a plurality of chambers. A common pressure is applied by the plurality of chambers in the carrier head using a common regulator, but a duration of application of the first pressure to each chamber from the plurality of chambers is controlled independently from other chambers.

Abstract: A method and system for reclaiming virgin test wafers by polishing a very thin layer from the wafer surface, applying a low down force between the wafer and the pad, with a dilute, low basic slurry. By polishing only a few hundred Angstroms of silicon from the wafer surface, a virgin test wafer may be repeatedly reclaimed and reused for periodic defect monitoring.

Abstract: A method is provided for processing a semiconductor topography. In an embodiment, the method includes positioning a semiconductor topography against a carrier plate with a raised section. Such a method preferably allows a larger area capable of producing a target yield of semiconductor devices within dimensional specifications to be obtained than is obtained by positioning the topography against a carrier plate with a flat surface. As such, positioning a topography against a carrier plate with one or more raised sections may form a substantially planar upper surface in a larger area than in an area formed by positioning such a topography against a flat surface carrier plate. Furthermore, such a method is preferably conducted in a single polishing step. As such, a polishing system is provided which includes a carrier plate with a raised section adapted to planarize a semiconductor topography in one polishing step.

Abstract: A chemical mechanical polish apparatus comprises a platen having a polishing pad thereon, a wafer carrier holding a wafer on the polishing pad, and a pusher. The pusher has a base disk and at least two guiding structures at the rim of the base disk. Each guiding structure has a shell with an opening, an elastic device and a pin moving through the opening, wherein the opening is non-linear.

Abstract: A polishing head assembly for retaining an object that is subject to polishing with a polishing pad is disclosed. The polishing head assembly comprises a head retainer assembly movably coupled to a wafer carrier head. The head retainer assembly includes a gimbal post and a load suspension plate. The gimbal post and the load suspension plate are operable to transfer a loading force to the wafer carrier head during polishing. The gimbal post also provides gimballing to optimize the position of the object in parallel with the polishing pad. In addition, the load suspension plate provides distribution of the loading force to optimize the flatness of the object during polishing.

Abstract: A polishing head with a floating knife-edge mechanism includes a base, a retaining ring secured to the base defining a pocket area beneath the base, and a lower assembly floating within the pocket area via a diaphragm seal. The lower assembly includes a disk-shaped support plate having a plurality of apertures distributed in a center region of the support plate, a clamp ring used to secure the diaphragm seal along a rim region of the support plate, and the floating knife-edge mechanism positioned between the rim region and the center region of the support plate.

Abstract: An apparatus (10) for wafer grinding includes sensors (38) and a spectral analyzer to perform a spectral analysis of light received by the sensors (38) during grinding of a semiconductor wafer (12). Based on the spectral analysis, the grinding process is stopped or the force applied to the semiconductor wafer is modified. This in situ monitoring decreases breakage and overheating of the semiconductor wafer (12).

Abstract: A method is suitable for cleaning substrates, after polishing, that require a high degree of cleanliness, such as semiconductor wafers, glass substrates, or liquid crystal displays. The method includes polishing a substrate using an abrasive liquid containing abrasive particles, and cleaning a polished surface of the substrate by supplying a cleaning liquid having substantially the same pH as the abrasive liquid or similar pH to the abrasive liquid so that a pH of the abrasive liquid attached to the polished surface of the substrate is not rapidly changed.

Abstract: One polishing media for chemical mechanical planarization includes an underlayer and a plurality of pressure sensors provided on the underlayer. At least some of the pressure sensors have a pad asperity provided thereon. The pressure sensors may be micro electromechanical systems (MEMS) pressure transducers or MEMS thermal actuators that monitor at least one of localized strain and temperature variation. Another polishing media includes a plurality of chemical sensors. Yet another polishing media includes pressure sensors, chemical sensors, and piezoelectric elements. Based upon the sensory outputs received from adjacent sensors, the piezoelectric elements provide active control to the process input by, for example, inducing localized vibration to modify the spatial removal behavior, inducing localized electric fields, or inducing localized heating/cooling elements.

Abstract: In a chemical mechanical polishing apparatus in accordance with the present invention, a material having a hardness defined by JIS standard K6301 (A type) of 10-40 and a thickness of 5-30 mm is used as an elastic member (16) arranged between a polishing pad (12) and a platen (36). Therefore, both flatness and uniformity of a wafer can be sufficiently improved.

Abstract: In a CMP process for polishing copper and a barrier metal formed on a substrate to form a buried copper interconnect, a polishing pad is subjected to dressing under a dressing pressure of 29 g/cm2 so that the surface roughness of the polishing pad becomes 3 &mgr;m to 5 &mgr;m inclusive. Thereby, dishing of the copper interconnect can be reduced as compared with a known method without reducing the removal rate of the copper and barrier metal.

Abstract: A polishing head assembly for use in a chemical mechanical planarization apparatus is provided. The polishing head assembly includes a carrier head shaped substantially like a disk having a circumference, a top surface, a bottom surface, and an outer wall, the outer wall having a groove therein, the groove extending into the carrier head from the bottom surface of the carrier head, and the groove running the entire circumference of the carrier head; and a retainer ring having an interior wall and an exterior wall, the interior wall of the retainer ring being in contact with the outer wall of the carrier head, the interior wall having a slot therein, the slot defining a lower portion of the interior wall as a flexible leg, the flexible leg having a receiving end that is adapted to secure an object having a surface to be polished, the slot having a first terminal end adjacent to the groove in the carrier head and a second terminal end, opposite the first terminal end, in the body of the retainer ring.

Abstract: Apparatuses and methods for planarizing a microelectronic-device substrate assembly on a planarizing pad. In one aspect of the invention, material is removed from the substrate assembly by pressing the substrate assembly against a planarizing surface of a planarizing pad and moving the substrate assembly across the planarizing surface through a planarizing zone. The method also includes replacing at least a portion of a used volume of planarizing solution on the planarizing surface with fresh planarizing solution during the planarization cycle of a single substrate assembly. The used planarizing solution can be replaced with fresh planarizing solution by actively removing the used planarizing solution from the pad with a removing unit and depositing fresh planarizing solution onto the pad in the planarizing zone.

Abstract: An apparatus for applying different amounts of pressure to different locations of a backside of a semiconductor device structure during polishing thereof. The apparatus is configured to be associated with a wafer carrier of a polishing apparatus and includes pressurization structures configured to be biased against the backside of the semiconductor device structure during polishing thereof. The pressurization structures are independently movable with respect to one another. The amount of force or pressure applied by each pressurization structure to the backside of the semiconductor device structure is controlled by at least one corresponding actuator. The actuator may magnetically facilitate movement of the corresponding pressurization structure toward or away from the backside of the semiconductor device structure. The actuator may alternatively comprise a positive or negative pressure source.

Abstract: Embodiments of the present invention are directed to a carrier head for positioning a substrate on a polishing surface. The carrier head includes a housing connectable to a drive shaft to rotate therewith; a base; a detachable plate removably mounted on top of the housing; a gimbal mechanism connecting the housing to the base to permit the base to move with respect to the housing such that the base remains substantially parallel to the polishing surface; and a flexible membrane defining a mounting surface for the substrate.

Abstract: Conditioning systems and methods for conditioning polishing pads used in mechanical and chemical-mechanical planarization of microelectronic-device substrate assemblies. In one aspect of the invention, a conditioning system includes a conditioning element or conditioning member having a conditioning face configured to engage a polishing pad. The conditioning face preferably includes a bonding medium covering at least a portion of the conditioning face and a plurality of conditioning particles attached to the bonding medium. The conditioning system also includes a corrosion-inhibiting unit that can be coupled to the conditioning element or a liquid on the polishing pad. The corrosion-inhibiting unit retards corrosion of the bonding medium in the presence of chemicals on the polishing pad that would otherwise corrode the bonding medium.

Abstract: An electrochemical planarization apparatus for planarizing a metallized surface on a workpiece includes a polishing pad and a platen. The platen is formed of conductive material, is disposed proximate to the polishing pad and is configured to have a negative charge during at least a portion of a planarization process. At least one electrical conductor is positioned within the platen. The electrical conductor has a first end connected to a power source. A workpiece carrier is configured to carry a workpiece and press the workpiece against the polishing pad. The power source applies a positive charge to the workpiece via the electrical conductor so that an electric potential difference between the metallized surface of the workpiece and the platen is created to remove at least a portion of the metallized surface from the workpiece.

Abstract: A polishing head for polishing the end surface of a semiconductor wafer has a driver roller, a driving motor for rotating it, a pair of upper and lower follower rollers one above the other parallel to and horizontally separated from the driver roller and an endless polishing belt around these rollers. As the driving motor causes the polishing belt to run around the rollers, the semiconductor wafer is pushed against the polishing belt between the upper and lower follower rollers. A pair of upper and lower tension-controlling rollers are provided for controlling the tension in the polishing belt between the two follower rollers. At least one of these tension-controlling rollers is movable vertically. A polisher is formed with such a polishing head, a holder for holding and rotating the wafer and an attaching device for attaching the polishing head to the polisher.

Abstract: A wear ring assembly is provided for use in a workpiece (e.g. a semiconductor wafer) polishing apparatus. The wear ring assembly comprises a wear element and a backing ring. The backing ring includes a fulcrum and is configured to transfer a component of pressure applied to the backing ring to the wear element via the fulcrum. In this manner, a substantially uniform vertical displacement of the wear ring is achieved.

Abstract: There is disclosed is a chemical mechanical polishing apparatus having a inexpensive simplified configuration, which minimizes consumption of slurry material and securely enabling washing of a polishing pad. By virtue of the provision of the inventive slurry stoppers, the chemical mechanical polishing apparatus prevents slurry from vainly falling off from the polishing pad in the course of polishing a wafer, and yet, while washing the polishing pad, in order that slurry not to remain on the polishing pad, and yet, in order that an end of adjoining slurry stoppers can be disposed across predetermined intervals in the inner and outer directions of the polishing pad, a plurality of slurry stoppers are retained to the polishing pad across substantially equal angular intervals along external periphery of the polishing pad by applying adhesive agent for example.

Abstract: An automatic system for repairing scratches on optically-read discs, (e.g., compact discs often called “CD's” or DVD's). More specifically, an automatic system for refurbishing a plurality of disc surfaces at substantially the same time, such that when refurbished, an optical reader, which uses a laser to read digital information stored on such a disc, can read the digital information on the disc without the optical distortion caused by a scratch.

Abstract: Embodiments of the invention include methods and apparatus for electrodialytic polishing of various layers formed on semiconductor substrates. In certain embodiments the use of electrodialytic processes in conjunction with chemical mechanical forces to achieve a copper interconnect with a desired level of planarity and process performance. In certain embodiments electrodialytic polishing uses an electrodialytic polish pad, which is an active pad which has copper binding groups provided in its core structure and has an added capability of allowing electrical conductivity. An electrodialytic polish pad allows transfer of cations or anions through a membrane in the presence of an electric field and into a cathodic electrolyte. Under the influence of an electric field the electrodialytic polish pad and/or electrodialytic pads are continuously refreshed to bind cations.

Abstract: A carrier head for a chemical mechanical polishing apparatus includes a flexible membrane that applies a controllable load to a substrate in an area with a controllable inner diameter.

Abstract: The methods and systems described provide for an in-situ endpoint detection for material removal processes such as chemical mechanical polishing (CMP) performed on a workpiece. In a preferred embodiment, an optical detection system is used to detect endpoint during the removal of planar conductive layers using CMP. An optically transparent polishing belt provides endpoint detection through any spot on the polishing belt. Once endpoint is detected, a signal can be used to terminate or alter a CMP process that has been previously initiated.

Abstract: The present invention relates to a polishing apparatus for restoring an optical disk. The objects of the present invention are as follows: to obtain an equal pressure appropriately required for polishing; to correct the accuracy of parallelism between the rotation planes of an optical disk and a polishing sheet; to remove roundness formed on the outer edge of an optical disk and unevenness in polishing; and to prevent clogging of the surface of a polishing sheet by the active elimination of abrasive filings and an occurrence of scratches on the surface of an optical disk due to the clogging. For the purpose of achieving the above objects, in an apparatus for polishing an optical disk composed of a disk rotator A and a polishing mechanism B, the polishing mechanism B has an elastic mechanism D for elastically holding a polishing pad C, a polishing sheet of the polishing pad C has such an elasticity that the deformation amount &Dgr;x is 0.005 mm to 0.

Abstract: A platen having a patterned upper surface for supporting a polishing material in a chemical mechanical polishing system is provided. In one embodiment, a platen for supporting a polishing material in a chemical mechanical polishing system includes a body adapted to support a polishing material during processing and having a substantially rigid non-planar upper support surface for supporting the polishing material during polishing.

Abstract: In a polishing apparatus having a cover body with fluid pressing mechanism, during polishing, vibration and migration of sticking portion between a retainer and a membrane generated in downstream of rotation of a polishing platen is prevented by reducing sticking force between the retainer and the membrane to less than force needed to wafer polishing with rotation of the cover body.

Abstract: A refining apparatus having magnetically responsive refining elements that can be smaller than the workpiece being refined are disclosed. The refining apparatus can supply a parallel refining motion to the refining element(s) through magnetic coupling forces. The refining apparatus can supply multiple different parallel refining motions to multiple different refining elements solely through magnetic coupling forces to improve refining quality and versatility. New refining methods, refining apparatus, and refining elements disclosed. Methods of refining using frictional refining, chemical refining, tribocbemical refining, and electrochemical refining and combinations thereof are disclosed. A refining chamber can be used. New methods of control are refining disclosed. The new magnetic refining methods, apparatus, and magnetically responsive refining elements can help improve yield and lower the cost of manufacture for refining of workpieces having extremely close tolerances such as semiconductor wafers.

Abstract: A retaining ring to be fitted on a chemical mechanical polishing apparatus for semiconductor wafers is disclosed, the retaining ring being of integral design made of a plastic material, wherein the retaining ring forms on a first front side thereof a bearing surface for supporting the retaining ring on a polishing surface of the polishing apparatus, and includes on the side thereof lying opposite the first front side thereof in axial direction fitting elements for fitting the retaining ring on the polishing apparatus.

Abstract: The present invention uses some type of inflatable membrane during processing to establish a vacuum and/or provide a resilient cushion on which the backside of the wafer can rest. In one aspect, the present invention provides an outer vacuum that allow for attachment of the wafer to the carrier head during processing, and also provides an inner inflatable membrane that provides a resilient cushion on which the backside of the wafer can rest during processing. In other aspects, the present invention provides a membrane that is displaceable with a vacuum within certain cavity regions to provide for attachment of the wafer to the wafer carrier.

Abstract: Apparatuses and methods for planarizing a microelectronic-device substrate assembly on a planarizing pad. In one aspect of the invention, material is removed from the substrate assembly by pressing the substrate assembly against a planarizing surface of a planarizing pad and moving the substrate assembly across the planarizing surface through a planarizing zone. The method also includes replacing at least a portion of a used volume of planarizing solution on the planarizing surface with fresh planarizing solution during the planarization cycle of a single substrate assembly. The used planarizing solution can be replaced with fresh planarizing solution by actively removing the used planarizing solution from the pad with a removing unit and depositing fresh planarizing solution onto the pad in the planarizing zone.

Abstract: A chemical mechanical head includes a retaining ring to maintain a substrate beneath the mounting surface during polishing. The retaining ring has a lower portion with a bottom surface for contacting a polishing pad during polishing and made of a first material, such as plastic, and an upper portion made of a second, different material, such as metal.

Abstract: An apparatus for improving performance of a wafer polishing apparatus is described. The apparatus includes a platen in a support assembly having a plurality of fluid channels and at least one region of altered topography positioned on a portion of the platen surface.

Abstract: Apparatuses and methods for planarizing a microelectronic-device substrate assembly on a planarizing pad. In one aspect of the invention, material is removed from the substrate assembly by pressing the substrate assembly against a planarizing surface of a planarizing pad and moving the substrate assembly across the planarizing surface through a planarizing zone. The method also includes replacing at least a portion of a used volume of planarizing solution on the planarizing surface with fresh planarizing solution during the planarization cycle of a single substrate assembly. The used planarizing solution can be replaced with fresh planarizing solution by actively removing the used planarizing solution from the pad with a removing unit and depositing fresh planarizing solution onto the pad in the planarizing zone.

Abstract: A wafer polishing apparatus for polishing a semiconductor wafer. The polisher comprises a base, a turntable, a polishing pad and a head drive mechanism for driven rotation of a polishing head. The polishing head comprises a sealing ring adapted to hold at least one wafer for engaging a front surface of the wafer with a work surface of the polishing pad. The sealing ring allows for application of uniform air pressure over the rear surface of the wafer. The sealing ring is constructed so that the wafer itself defines a portion of a pressure cavity receiving pressurized air.

Abstract: Disclosed is a chemical mechanical polishing pad formed with holes, grooves or a combination thereof. The chemical mechanical polishing pad is characterized in that a plurality of concentric circles each having grooves, holes, or a combination thereof are formed at a polishing surface of the polishing pad. The chemical mechanical polishing pad provides effects of effectively controlling a flow of slurry during a polishing process, thereby achieving a stability in the polishing process in terms of a polishing rate, and achieving an enhancement in the planarization of a wafer.

Abstract: 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.

Abstract: A holder for flat workpieces, particularly semiconductor wafers, particularly in an apparatus for chemico-mechanically polishing the semiconductor wafers, comprising a disk-like head which is adapted to be connected to a spindle adjustable in height at the upper surface and has a support plate at the lower side which, via a universal joint, is coupled to a carrier portion disposed above the support plate or the spindle and which has a number of vertical bores which extend to the underside of the support plate and can be optionally connected to a vacuum and/or a fluid source under pressure, where the support plate is guided to be movable in height in the carrier portion and displacing means are provided between the carrier portion and the support plate to displace the support plate with respect to the carrier portion and to exert a predetermined pressure on the workpiece, characterized in that a ring-shaped loading member of limited width is provided which is movably supported in an axially parallel way in the

Abstract: Disclosed is a chemical mechanical polishing pad formed at a polishing surface thereof with micro-holes each having a desired cross-sectional area while having a desired depth. The shape, size, and density of the micro-holes can be optionally adjusted. The chemical mechanical polishing pad provides an effect of maintaining a desired polishing rate during a polishing process. In accordance with the present invention, the micro-holes can have diverse arrangements depending on given process conditions.