Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B24—GRINDING; POLISHING
  • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
  • B24B37/00—Lapping machines or devices; Accessories
  • B24B37/04—Lapping machines or devices; Accessories designed for working plane surfaces
  • B24B37/07—Lapping machines or devices; Accessories designed for working plane surfaces characterised by the movement of the work or lapping tool
  • B24B37/08—Lapping machines or devices; Accessories designed for working plane surfaces characterised by the movement of the work or lapping tool for double side lapping
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B24—GRINDING; POLISHING
  • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
  • B24B55/00—Safety devices for grinding or polishing machines; Accessories fitted to grinding or polishing machines for keeping tools or parts of the machine in good working condition
  • B24B55/02—Equipment for cooling the grinding surfaces, e.g. devices for feeding coolant
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B24—GRINDING; POLISHING
  • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
  • B24B37/00—Lapping machines or devices; Accessories
  • B24B37/11—Lapping tools
  • B24B37/12—Lapping plates for working plane surfaces
  • B24B37/16—Lapping plates for working plane surfaces characterised by the shape of the lapping plate surface, e.g. grooved
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B24—GRINDING; POLISHING
  • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
  • B24B49/00—Measuring or gauging equipment for controlling the feed movement of the grinding tool or work; Arrangements of indicating or measuring equipment, e.g. for indicating the start of the grinding operation
  • B24B49/16—Measuring or gauging equipment for controlling the feed movement of the grinding tool or work; Arrangements of indicating or measuring equipment, e.g. for indicating the start of the grinding operation taking regard of the load
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B24—GRINDING; POLISHING
  • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
  • B24B55/00—Safety devices for grinding or polishing machines; Accessories fitted to grinding or polishing machines for keeping tools or parts of the machine in good working condition
  • B24B55/02—Equipment for cooling the grinding surfaces, e.g. devices for feeding coolant
  • B24B55/03—Equipment for cooling the grinding surfaces, e.g. devices for feeding coolant designed as a complete equipment for feeding or clarifying coolant
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B24—GRINDING; POLISHING
  • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
  • B24B57/00—Devices for feeding, applying, grading or recovering grinding, polishing or lapping agents
  • B24B57/02—Devices for feeding, applying, grading or recovering grinding, polishing or lapping agents for feeding of fluid, sprayed, pulverised, or liquefied grinding, polishing or lapping agents

Definitions

• the invention relates to a device for double side machining of flat workpieces, comprising an upper working disk and a lower working disk, wherein the working disks form a working gap between their facing working surfaces for machining the workpieces, and wherein at least one of the working disks has a plurality of holes extending through the working surface for supplying a liquid working fluid in the working gap.
• the invention also relates to a method for operating a device for double side machining of flat workpieces, wherein the apparatus comprises an upper working disk and a lower working disk, wherein the working disks between their facing work surfaces form a working gap for machining the workpieces, and wherein at least one of the working disks a Has a plurality of extending through the working surface bores for supplying a liquid working fluid in the working gap.
• Such devices and methods are used, for example, for double-side polishing of semiconductor wafers.
• a polishing liquid is introduced into the working gap as the working medium.
• the polishing wheel described therein has a series of axially parallel bores which are aligned with corresponding bores in the support plate carrying said polishing pad and connected to lines through which a polishing agent is directed to the working surface of the polishing pad.
• the bores are provided in the upper working disk, wherein the polishing agent is conveyed by gravity down into the polishing nip.
• a problem is that not always a uniform polishing agent supply in the Working gap can be guaranteed. In particular, it comes in areas of the polishing pad, which are often swept over by workpieces during machining, to a polishing agent depletion. This can affect the polishing result.
• the present invention seeks to provide a device and a method of the type mentioned, with which at any time a sufficient working fluid supply is ensured in the working gap.
• the invention solves the problem in that the holes for the liquid supply are combined into several groups, each group of holes is connected to a separate pressurized supply line for the working fluid, and wherein at least one pressure regulating device is provided, with which the working fluid pressure in the supply lines can be controlled separately.
• the invention solves the problem in that the holes are combined into several groups, each group of bores pressurized working fluid is supplied, and wherein the working fluid pressure of the groups respectively supplied working fluid is controlled separately.
• the processing according to the invention can be material-removing.
• the device may be, for example, a device for polishing both sides of flat workpieces.
• the working fluid may accordingly be a polishing fluid. But it comes Other machining methods in question, such as grinding or lapping.
• the workpieces to be machined, for example, plane-parallel according to the invention may be, for example, semiconductor wafers.
• the work disks may be, for example, annular. Accordingly, the working gap may be annular. With one or both working disks can be connected to a vertical drive shaft. If the working disks are each supported by a carrier disk, this connection can be made through the carrier disk.
• At least one of these drive shafts can be rotationally driven by a suitable drive, so that correspondingly the working disk connected to this drive shaft is moved in rotation. Between the relatively rotating work disks, the workpieces are processed.
• the working wheels for example, the upper working disk, through holes are provided. Of course, such holes can also be provided in both working wheels.
• suitable pressure lines such as pressure hoses or pressure pipes, run, which promote the working fluid to the working gap.
• the plurality of provided bores are divided into a plurality, for example three or more, groups.
• the groups are each assigned a pressurized supply line.
• a total of three or more pressurized supply lines can then be provided.
• certain working gap zones can each be supplied with work equipment by a group of bores.
• the working fluid pressure is the pressure prevailing in the bores or pressure lines filled with working fluid. It determines the flow rate of working fluid from the holes in the working gap.
• the invention enables a separate control of the working fluid pressure and thus of the working fluid flow in the working gap for the individual supply lines and thus for the individual of these with Work equipment supplied hole groups or work gap zones.
• the supply of working medium for example with a polishing agent
• the working fluid flow can be regulated depending on the operating parameters (recipe-guided).
• the zones or groups can be classified so that the holes of a zone are exposed during operation of the device largely the same operating conditions.
• the holes of a work nip zone during operation can be overrun substantially equal parts of workpieces.
• the holes can be assigned to a group, for example, in certain radial areas of the working gap. It then groups are formed from lying in annular zones holes. Through the zones or groups can then be ensured in each case by a common control for this zone of the pressure and thus the flow through the holes each optimal working fluid supply.
• the work equipment is thereby used more effectively, so that the total work equipment requirement is reduced. Scratches or similar machining errors are more reliably avoided.
• can be relative smooth polishing cloths are used. If desired, workpieces can be rinsed off, for example, by a top working disk provided with the bores, by briefly increasing the working fluid pressure considerably. An undesirable adhesion of the workpieces when lifting the upper working disk after the end of the process is thus reliably avoided. It is also possible to selectively vary the amount of working fluid supplied to the working gap, for example a quantity of polishing agent, in order, for example, to cool regions with an elevated process temperature. This further optimizes the work result.
• the supply lines can be connected on the one hand with a common main pressure supply line and on the other hand with the holes of a group.
• the main supply line communicates with a working fluid reservoir and may, for example, comprise a pump with which the working fluid is pumped through the main supply line to the individual supply lines.
• a pressure control unit is arranged, with which the working fluid pressure in the respective supply line can be regulated independently of the other supply lines.
• the measurement signals are present at corresponding flow control devices that regulate the liquid flow due to the measurement signals of the flow measuring devices.
• the supply lines can be in a conventional manner ring lines or ring channels, which are connected to a plurality of supply lines, for example supply hoses, which extend through the bores of the working disk.
• Such pressure-tight ring lines are used in a particularly simple and reliable way to supply a variety of communicating with these lines.
• the common main pressure supply line may further through one of the at least one provided with the bores Working disk associated vertical drive shaft be guided.
• the vertical drive shaft is driven in rotation by a drive, such as a motor. As a result, the working disk connected to the drive shaft is rotated.
• a pressure-tight single-channel rotary input is provided by the drive shaft in order to distribute the working fluid to the various supply lines.
• the cross-section of the holes or the cross-section of guided in the holes liquid lines in the region of their opening into the working surface end can be reduced.
• the cross section may decrease by more than 50%.
• a measuring device for measuring the torque applied by a rotary drive to at least one connected to at least one of the working wheels vertical drive shaft torque may be provided, wherein the control device of the measuring device compares measured torque with a desired torque or range of torque and, in the event of a deviation of the measured torque from the desired torque or range, modifies the fluid pressure in at least some supply lines such that the measured torque resumes the desired torque or is within the desired torque range. It may further be provided that the control device compares the measured torque with a predetermined limit torque.
• the controller reduces the working fluid pressure in at least some supply lines so that the measured torque again assumes a value above the limit torque.
• This refinement is based on the knowledge that when the working gap is over-supplied with working fluid, the torque to be applied by the drive to reach a predetermined rotational speed decreases suddenly, similar to aquaplaning. This leads to an undesirable impairment of workpiece machining. Therefore, in such a case, the working fluid supply is lowered by a pressure reduction in the supply lines until the torque is again in the predetermined range. In particular, the pressure can be Of course, changed in all supply lines, in particular reduced.
• the holes can be grouped together, depending on how often they are obscured during operation of the device by the workpieces to be machined.
• the working fluid pressure in the supply lines of the groups can in each case be set the higher, the more frequently the bores of a respective group during operation of the device are covered by the workpieces to be machined.
• Different target pressure values for the respective supply line are thus specified for the various groups, with the target pressure values being selected depending on the frequency of obstruction of the bores through the workpieces to be processed, which is to be expected during operation.
• According to the invention can be provided in a conventional manner runners with at least one, in particular a plurality of receptacles, in which the workpieces to be machined are kept floating.
• the carriers are rotationally driven in the working gap, with the workpieces held in them moving along cycloidal paths in the working gap. In workpiece machining, this results in different residence probabilities in the radial direction of the working gap.
• the probability of residence of the workpieces in the edge regions of the working gap and in particular at the inner edge may be higher than, for example, in the middle. This fact is taken into account by the aforementioned embodiment.
• holes in certain ring zones of the working gap can be grouped together, with each of the ring zones being assigned a certain probability of occupancy for the workpieces. The higher this probability of residence for one of these ring zones or groups, the greater the desired working fluid pressure for the supply line assigned to this group.
• the control can be carried out in such a way that the overall result is a very homogeneous distribution of the working fluid in the entire working gap.
• the inventive method can be carried out in particular with the device according to the invention. Accordingly, the device is suitable for carrying out the method according to the invention.
• Fig. 1 shows a part of a device according to the invention in a vertical
• Fig. 2 is an enlarged view of a detail of a view according to
• Fig. 3 is an enlarged view of the detail B of Fig. 2, and
• Fig. 4 is a circuit diagram for illustrating the control according to the invention.
• a detail of a device 10 according to the invention for double-side machining of flat workpieces is shown.
• the device is a Doppel togetherpoliermaschine for plane-parallel polishing of semiconductor wafers.
• the device has three supply lines 36 coming from a polishing liquid reservoir, which are each guided via a connecting piece 22 and a multi-channel rotation guide 18 through a vertical drive shaft 20 of the device.
• polishing liquid can be conveyed out of the liquid reservoir through the supply line.
• the supply lines 36 form in the example shown in each case a ring line 36 with outlets to the respective group of holes.
• the supply lines 36 may be formed by supply hoses.
• pressure control devices are provided, which are each designed to regulate the working fluid pressure in one of the supply lines 36, as will be explained in more detail below.
• the device 10 also has, in a manner known per se, an upper and lower annular carrier disk and an annular upper or lower working disk respectively connected to the upper and lower carrier disk.
• Fig. 1 only the upper support plate 38 and associated with this upper working disk 40 are shown.
• the upper carrier disk 38 is annular.
• the device 10 has a substantially symmetrical to the upper carrier and working disk 38, 40 formed, not shown lower carrier disk and working disk. Between their facing annular work surfaces, of which in Fig. 1, the working surface of the upper working disk 40 is shown at reference numeral 46, limit the work discs an annular working gap.
• the basic structure of such Doppelurgiermaschine with upper and lower working wheels is known per se and described for example in DE 100 07 390 AI.
• a plurality of axial through holes 48 is provided by the upper working disk 40, each aligned with corresponding through holes 50 in the upper support plate 38.
• pressure tubes 52 extend through the bores.
• the annular supply lines 36 are in each case in connection with the upper openings of the pressure tubes 52.
• the design of the holes 48, 50 and the pressure pipes 52 will be explained in more detail with reference to the enlarged views in Figures 2 and 3.
• a larger number of supply lines 36, through bores 48, 50 and pressure pipes 52 are provided. Apart from that, the exemplary embodiments do not differ.
• FIGS. 1 it can be further seen that a plurality of axial through holes 48 is provided by the upper working disk 40, each aligned with corresponding through holes 50 in the upper support plate 38.
• pressure tubes 52 extend through the bores.
• the annular supply lines 36 are in each case in connection with the upper openings of the pressure tubes 52.
• the design of the holes 48, 50 and the pressure pipes 52 will be explained in more detail with reference to the enlarged
• the pressure pipes 52 are in each case connected to the ring lines 36 at their upper end via a connection 54.
• the pressure pipes 52 are made of a plastic, for example.
• a metallic sleeve 58 is used in each case.
• the pressure pipes 52 In the area of their opening into the working surface 46 end seals a ring seal 60, the pressure pipes 52 relative to the sleeve 58 from.
• the pressure pipes 52 have a considerable cross-sectional reduction 62 of more than 50% at their lower end.
• the outlet opening 64 of the pressure pipes 52 thus has a considerably smaller diameter than the main area 66 of the pressure pipes 52.
• bores 48, 50 are arranged at different radial distances from the working and carrier discs.
• the upper working disk and thus also the upper support disk carrying it has a plurality of circularly extending at different radial distances from the running through the vertical drive shaft 20 central axis of rotation of the working disk 40 and carrier disk 38 extending rows of axial bores.
• the holes of a radial distance are each combined into a group and supplied by a ring line 36 with polishing agent.
• a pump 68 is polishing from a connected to the pump 68 via a check valve 70 not shown polishing agent reservoir in the supply lines 36 required. From there, the polishing agent is further demanded to the pressure control devices 35.
• the supply lines 36 are still each a two-way valve 72 for switching on and off of the supply lines 36 respectively supplied supply circuits.
• the pressure control devices 35 With the pressure control devices 35, the polishing agent pressure in each of the ring lines 36 can be regulated separately to a specific value.
• a flow meter 74 is located in each of the supply lines 36. Such a control or flow control is known per se to a person skilled in the art and will therefore not be explained in detail.
• the workpieces to be machined can, for example, be held in carriers in a manner known per se so that they move in the working gap along cycloidal paths. This results in different probabilities of residence of the workpieces in the working gap during processing.
• the different radial groups of holes in the upper working disk 40 are covered with different amounts of workpieces during operation. This can be considered according to the invention by applying the presumably more frequently concealed radial areas of bores by means of the ring line 36 assigned to them in each case and the corresponding pressure regulating device 35 to a higher working medium pressure.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
• Mechanical Treatment Of Semiconductor (AREA)
• Grinding-Machine Dressing And Accessory Apparatuses (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=43589852

Family Applications (1)

Country Status (7)

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Citations (1)

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• 2009
  • 2009-11-05 DE DE102009052070A patent/DE102009052070A1/de active Pending
• 2010
  • 2010-10-28 EP EP10781601A patent/EP2496384A1/de not_active Withdrawn
  • 2010-10-28 JP JP2012535678A patent/JP5689891B2/ja active Active
  • 2010-10-28 CN CN2010800499645A patent/CN102666015A/zh active Pending
  • 2010-10-28 US US13/505,439 patent/US20120220197A1/en not_active Abandoned
  • 2010-10-28 KR KR1020127011032A patent/KR101824564B1/ko active IP Right Grant
  • 2010-10-28 WO PCT/EP2010/006602 patent/WO2011054481A1/de active Application Filing

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