EP1224067B1 - Device and method for separating materials - Google Patents

Device and method for separating materials Download PDF

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Publication number
EP1224067B1
EP1224067B1 EP01984580A EP01984580A EP1224067B1 EP 1224067 B1 EP1224067 B1 EP 1224067B1 EP 01984580 A EP01984580 A EP 01984580A EP 01984580 A EP01984580 A EP 01984580A EP 1224067 B1 EP1224067 B1 EP 1224067B1
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EP
European Patent Office
Prior art keywords
lubricant
coolant
cutting
cutting disk
supplied
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EP01984580A
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German (de)
French (fr)
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EP1224067A1 (en
Inventor
Ralf Hammer
Ralf Gruszynsky
André KLEINWECHTER
Tilo Flade
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Freiberger Compound Materials GmbH
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Freiberger Compound Materials GmbH
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B28—WORKING CEMENT, CLAY, OR STONE
    • B28D—WORKING STONE OR STONE-LIKE MATERIALS
    • B28D5/00—Fine working of gems, jewels, crystals, e.g. of semiconductor material; apparatus or devices therefor
    • B28D5/0058—Accessories specially adapted for use with machines for fine working of gems, jewels, crystals, e.g. of semiconductor material
    • B28D5/0076—Accessories specially adapted for use with machines for fine working of gems, jewels, crystals, e.g. of semiconductor material for removing dust, e.g. by spraying liquids; for lubricating, cooling or cleaning tool or work

Definitions

  • the invention relates to an apparatus and a method for Separation of materials, especially single crystals.
  • FIG. 1 is a schematic View of inner hole cutting seen in a top view in the direction of the central longitudinal axis M of a single crystal 1.
  • How 1 is the single crystal 1, which is essentially cylindrical with a central longitudinal axis M. is attached to a bracket, not shown and along with it in one direction perpendicular to the central longitudinal axis M via a feed device, not shown traversable.
  • a cutting disc 2 is provided, which is a concentric There is inner hole core sheet 2a, the edge 3 surrounding the inner hole is set with diamond grains is and thus forms a cutting edge.
  • the width of the core sheet between its outer edge and its inner edge is larger than the diameter of the single crystal, which is why in the figure schematically shows only the inner edge.
  • the cutting disc 2 is about its central axis R over a Drive rotatable in the direction A shown in Fig. 1.
  • the Cutting disc and the single crystal are arranged to each other, that the axis of rotation R of the cutting disc 2 and the Center longitudinal axis M of the single crystal 1 parallel at a distance to each other.
  • the single crystal 1 is the feed device perpendicular to its central longitudinal axis M movable towards the cutting disc 2 that the cutting disc when rotating the single crystal 1 completely in a plane perpendicular to its central longitudinal axis M cuts through, and away from the cutting disc 2 in one position movable in which a separated wafer can be removed can.
  • a coolant-lubricant supply device 4 for supplying cooling lubricant to the Cutting edge provided in direction of rotation A according to the position P2 the exit of the cutting disc from the single crystal 1, hereinafter referred to as the outlet side.
  • a second Supply device for cooling lubricants provided in direction of rotation A according to the position P2 the exit of the cutting disc from the single crystal 1, hereinafter referred to as the outlet side. Operational is before the cutting disc 2 enters the single crystal 1 via the feed device 4 the cooling lubricant applied to the cutting edge or the cutting disc 2, which then by the rotation of the cutting disc 2 in the The resulting separation gap is transported.
  • the second feed device 5 again applied cooling lubricant, so that the cleaning and removal of worn away Material is guaranteed by the separation gap.
  • the Cooling lubricants are added to the surface tension reduce and thus the wetting of the cutting disc improve.
  • the known device also has a device for interval flushing of the core sheet and Clamping system.
  • the object is achieved by a device according to claim 1 or a method according to claim 9th
  • the device according to the invention and the invention Methods have the particular advantage that during less cooling lubricant is required during the separation process than in the known device. This makes a qualitative high quality cut.
  • the inventive Device in a known manner, the holder and the feed device for the single crystal 1 and the cutting disc 2 with the core sheet 2a and the diamond-trimmed edge 3 the inner hole of the cutting disc.
  • the device according to the invention has a device a first supply device 10 for supplying cooling lubricant on the edge 3 of the inner hole and on the Cutting disc 2, which in the direction of rotation of the cutting disc 2 seen on the outlet side at position P2 after Passage. Through the single crystal 1 is provided.
  • the first Feeding device 10 for cooling lubricants is for example designed as a nozzle.
  • a second feed device 11 for cleaning agent on the outlet side in the area of the inner hole It is also on the outlet side a device 12 for supplying a gaseous Medium, especially compressed air, on the cutting disc 2 and in particular the edge 3 is provided.
  • FIGS. 3 to 6 The operation of the device according to the invention and the device according to the invention The method can be seen from FIGS. 3 to 6.
  • the cutting disc is before the cutting or cutting process 2 and the single crystal 1 separated from each other. Then it will be the single crystal 1 moves relative to the cutting disc 2 and this occurs rotating in the material of the single crystal 1 Separate.
  • Fig. 3 As shown in Fig. 3, during the Separation process via the feed device 10 coolant-lubricant with a low volume flow, i.e. at slow speed v and low pressure p the edge 3, which the Forming cutting edge, fed via the feed device 10.
  • a cooling lubricant with a Additive that uses the surface tension ⁇ of the coolant-lubricant increases and thus the wetting of the core sheet 2a worsened. This results in poor wetting of the core sheet 2a of the cutting disc 2, and form it droplets 20 of the cooling lubricant on the surface of the core sheet 2a.
  • compressed air via the compressed air source 12 blown onto the edge 3, making the bad Wetting is balanced. The compressed air continues to carry to form and distribute droplets 20 at. As shown in Fig.
  • the method according to the invention is thus a two-stage process Process in which the cooling of the Separating tool, swirling the coolant, trapping of the removed material into the coolant lubricant droplets and distributing and storing the coolant lubricant droplets with the removed material below Centrifugal force acts.
  • a second stage after the single crystal is moved away from the cutting disc is the cleaning and the removal of worn material over high air pressure and sufficient cooling lubricant supply performed.
  • the one used in the second stage Detergent can be identical to the coolant-lubricant but it can also be another substance, e.g. water his. Thus, coolants and lubricants have different properties.
  • cooling and Lubrication requires much less cooling lubricant than for cleaning and removing the removed material.
  • On high quality cut can only be done with such a Apply a small amount of coolant and lubricant.
  • the amount of coolant-lubricant set to the minimum required amount to cool and guarantee lubrication.
  • the separation gap is free and the contact between the core sheet and the wafer section becomes avoided.
  • cleaning is a much higher one Volume flow optimal.
  • a container 30 is provided in the working position at a constant distance is located above the feed device 10 and the one Line 31 is connected to this. Located in the container coolant, which the feed device 10th via the line only under the influence of gravitation or is supplied to the hydrostatic pressure. Air bubbles in the Line are led upwards. This ensures that even with small amounts of coolant to be supplied ensures constant and bubble-free feeding is.
  • the invention is suitable for cutting a wide variety of materials, e.g. for optical glasses, plastics and others.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Processing Of Stones Or Stones Resemblance Materials (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
  • Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
  • Grinding-Machine Dressing And Accessory Apparatuses (AREA)
  • Auxiliary Devices For Machine Tools (AREA)
  • Mechanical Treatment Of Semiconductor (AREA)

Abstract

A method and a device for the division of materials, in particular of single crystals, in particular by inner hole cutting is provided, with a cutting disk (2) having a concentric hole whose edge (3) forms a cutting edge and wherein the cutting disk (2) is rotatable about its central axis in order to cut the single crystal (1), a positioning device for positioning the single crystal (1) to be cut relative to the cutting disk in such a way that the cutting disk moves in rotating manner through the single crystal in order to separate off a part (1a) of the single crystal (1), and a device for the supply of coolant-lubricant onto the cutting disk (2), wherein the device (10) for the supply of coolant-lubricant is arranged in such a way that viewed in the direction of rotation it supplies the coolant-lubricant on the exit side behind the passage of the cutting disk (2) through the single crystal (1), and a device for the supply of compressed air (12).

Description

Die Erfindung betrifft eine Vorrichtung und ein Verfahren zum Trennen von Werkstoffen, insbesondere von Einkristallen.The invention relates to an apparatus and a method for Separation of materials, especially single crystals.

Ein bekanntes verfahren (siehe z.B. JP-A-07 304 028) zum Trennen von Einkristallen, das insbesondere zur Erzeugung von Halbleiterwafern eingesetzt wird, ist das Innenlochtrennen. Fig. 1 ist eine schematische Darstellung zum Innenlochtrennen in einer Draufsicht gesehen in Richtung der Mittenlängsachse M eines Einkristalls 1. Wie aus Fig. 1 ersichtlich ist, ist der Einkristall 1, der im wesentlichen zylinderförmig mit einer Mittenlängsachse M ausgebildet ist, auf einer nicht dargestellten Halterung angebracht und zusammen mit dieser in einer Richtung senkrecht zur Mittenlängsachse M über eine nicht dargestellte Vorschubeinrichtung verfahrbar. Zum Trennen bzw. Schneiden der Wafer ist eine Trennscheibe 2 vorgesehen, die aus einem ein konzentrisches Innenloch aufweisenden Kernblech 2a besteht, dessen das Innenloch umgebender Rand 3 mit Diamantkörnern besetzt ist und somit einen Schneidrand bildet. Die Breite des Kernbleches zwischen seinem äußeren Rand und seinem inneren Rand ist größer als der Durchmesser des Einkristalls, weshalb in der Figur schematisch nur der innere Rand dargestellt ist. Die Trennscheibe 2 ist um ihre zentrale Achse R über einen Antrieb in der in Fig. 1 gezeigten Richtung A drehbar. Die Trennscheibe und der Einkristall sind so zueinander angeordnet, dass die Rotationsachse R der Trennscheibe 2 und die Mittenlängsachse M des Einkristalls 1 in einem Abstand parallel zueinander verlaufen. Ferner ist der Einkristall 1 mittels der Vorschubeinrichtung senkrecht zu seiner Mittenlängsachse M in Richtung auf die Trennscheibe 2 hin bewegbar so daß die Trennscheibe beim Rotieren den Einkristall 1 vollständig in einer Ebene senkrecht zu seiner Mittenlängsachse M durchschneidet, und von der Trennscheibe 2 weg in eine Stellung bewegbar in der ein abgetrennter Wafer entnommen werden kann.A known method (see e.g. JP-A-07 304 028) for separating single crystals, the used in particular for the production of semiconductor wafers is the inner hole cutting. Fig. 1 is a schematic View of inner hole cutting seen in a top view in the direction of the central longitudinal axis M of a single crystal 1. How 1 is the single crystal 1, which is essentially cylindrical with a central longitudinal axis M. is attached to a bracket, not shown and along with it in one direction perpendicular to the central longitudinal axis M via a feed device, not shown traversable. For cutting or cutting the wafers is a cutting disc 2 is provided, which is a concentric There is inner hole core sheet 2a, the edge 3 surrounding the inner hole is set with diamond grains is and thus forms a cutting edge. The width of the core sheet between its outer edge and its inner edge is larger than the diameter of the single crystal, which is why in the figure schematically shows only the inner edge. The cutting disc 2 is about its central axis R over a Drive rotatable in the direction A shown in Fig. 1. The Cutting disc and the single crystal are arranged to each other, that the axis of rotation R of the cutting disc 2 and the Center longitudinal axis M of the single crystal 1 parallel at a distance to each other. Furthermore, the single crystal 1 is the feed device perpendicular to its central longitudinal axis M movable towards the cutting disc 2 that the cutting disc when rotating the single crystal 1 completely in a plane perpendicular to its central longitudinal axis M cuts through, and away from the cutting disc 2 in one position movable in which a separated wafer can be removed can.

Innerhalb des das Innenloch umgebenden Randes 3 der Trennscheibe 2 ist in Drehrichtung A vor der Position P1 des Eintritts der Trennscheibe in den Einkristall 1, nachfolgend als eintrittsseitig bezeichnet, eine Kühl-Schmiermittel-Zuführvorrichtung 4 zum Zuführen von Kühl-Schmiermittel auf den Schneidrand vorgesehen. In Drehrichtung A nach der Position P2 des Austritts der Trennscheibe aus dem Einkristall 1, nachfolgend als austrittsseitig bezeichnet, ist eine zweite Zuführeinrichtung für Kühl-Schmiermittel vorgesehen. Im Betrieb wird vor dem Eintritt der Trennscheibe 2 in den Einkristall 1 über die Zuführvorrichtung 4 das Kühl-Schmiermittel auf den Schneidrand bzw. die Trennscheibe 2 aufgebracht, welches dann durch die Rotation der Trennscheibe 2 in den beim Trennen entstehenden Trennspalt transportiert wird. Beim Austritt der Trennscheibe 2 aus dem Einkristall 1 wird durch die zweite Zuführeinrichtung 5 erneut Kühl-Schmiermittel aufgebracht, so daß die Reinigung und der Abtransport von abgetragenem Material durch den Trennspalt gewährleistet ist. Dem Kühl-Schmiermittel werden Zusätze zugegeben, die die Oberflächenspannung herabsetzen und damit die Benetzung der Trennscheibe verbessern. Die bekannte Vorrichtung weist ferner eine Vorrichtung zur Intervallspülung des Kernbleches und des Spannsystems auf.Within the edge 3 of the cutting disc surrounding the inner hole 2 is in direction of rotation A before position P1 of the entrance the cutting disc in the single crystal 1, hereinafter as designated on the inlet side, a coolant-lubricant supply device 4 for supplying cooling lubricant to the Cutting edge provided. In direction of rotation A according to the position P2 the exit of the cutting disc from the single crystal 1, hereinafter referred to as the outlet side, is a second Supply device for cooling lubricants provided. Operational is before the cutting disc 2 enters the single crystal 1 via the feed device 4 the cooling lubricant applied to the cutting edge or the cutting disc 2, which then by the rotation of the cutting disc 2 in the The resulting separation gap is transported. At the exit the cutting disc 2 from the single crystal 1 is by the second feed device 5 again applied cooling lubricant, so that the cleaning and removal of worn away Material is guaranteed by the separation gap. the Cooling lubricants are added to the surface tension reduce and thus the wetting of the cutting disc improve. The known device also has a device for interval flushing of the core sheet and Clamping system.

Bei der bekannten Vorrichtung besteht das Problem, daß ein effektives Reinigen und der Abtransport des abgetragenen Materials während des Schnittes so viel Kühl-Schmiermittel erfordert, daß der Trennspalt mit Kühl-Schmiermittel und abgetragenem Material angefüllt wird. Dadurch kann es bei schmalen Trennspalten zur Berührung zwischen dem Kernblech der Trennscheibe 2 und dem Waferabschnitt kommen. Der Waferabschnitt wird durch Adhäsion an das Kernblech gezogen, und die Qualität des abgetrennten Wafers wird negativ beeinflußt. Bei großen Berührungsflächen kann es zum Wegreißen des Wafers kommen. Ist dagegen die Kühl-Schmiermittelmenge zu niedrig, reicht die Reinigungs- und Transportwirkung nicht mehr aus. Außerdem führen oberflächenentspannende Zusätze zu einer besseren Benetzung des Kernblechs, was die Verdunstung und das Eintrocknen des Sägeschlammes auf dem Kernblech fördert.In the known device, there is the problem that a effective cleaning and removal of the removed material requires so much coolant during the cut that the separation gap with coolant and lubricant Stuffed. This can make it narrow Separating gaps for contact between the core sheet of the Cutting disc 2 and the wafer section come. The wafer section is pulled to the core sheet by adhesion, and the The quality of the separated wafer is adversely affected. at Large contact areas can tear the wafer away come. On the other hand, if the amount of coolant / lubricant is too low, the cleaning and transport effect is no longer sufficient. In addition, surface-relaxing additives lead to a better one Wetting the core sheet, what the evaporation and that Drying the sawing sludge on the core sheet promotes.

Es ist Aufgabe der Erfindung, eine Vorrichtung und ein Verfahren zum Trennen von Wafern mittels Innenlochtrennen bereitzustellen, welche bzw. welches die oben beschriebenen Nachteile vermeidet. It is an object of the invention, an apparatus and a method to provide for the separation of wafers by means of inner hole cutting, which one or those described above Avoids disadvantages.

Die Aufgabe wird gelöst durch eine Vorrichtung nach Patentanspruch 1 bzw. ein Verfahren nach Patentanspruch 9. The object is achieved by a device according to claim 1 or a method according to claim 9th

Weiterbildungen der Erfindung sind in den Unteransprüchen angegeben.Developments of the invention are specified in the subclaims.

Die erfindungsgemäße Vorrichtung und das erfindungsgemäße Verfahren weisen insbesondere den Vorteil auf, daß während des Trennvorgangs weniger Kühl-Schmiermittel benötigt wird als bei der bekannten Vorrichtung. Dadurch wird ein qualitativ hochwertiger Schnitt erzeugt.The device according to the invention and the invention Methods have the particular advantage that during less cooling lubricant is required during the separation process than in the known device. This makes a qualitative high quality cut.

Weitere Merkmale und Zweckmäßigkeiten der Erfindung ergeben sich aus der Beschreibung von Ausführungsbeispielen anhand der Figuren.Further features and advantages of the invention result itself from the description of exemplary embodiments on the basis of the figures.

Von den Figuren zeigen:

Fig. 1
eine schematische Darstellung gesehen in Draufsicht in Richtung einer Einkristall-Längsachse einer bekannten Vorrichtung;
Fig. 2
eine schematische Darstellung einer Ausführungsform der erfindungsgemäßen Vorrichtung gesehen in Draufsicht in Richtung der Einkristall-Mittenlängsachse;
Fig. 3
eine schematische Darstellung des Kühlungsschrittes des erfindungsgemäßen Verfahrens;
Fig. 4
eine schematische Darstellung eines Schrittes des Verteilens des Kühl-Schmiermittels auf dem Trennwerkzeug vor dem Schnitt;
Fig. 5
eine schematische Darstellung des Schrittes des Trennens; und
Fig. 6
eine schematische Darstellung des Reinigungsschrittes bei dem erfindungsgemäßen Verfahren.
From the figures show:
Fig. 1
a schematic representation seen in plan view in the direction of a single crystal longitudinal axis of a known device;
Fig. 2
a schematic representation of an embodiment of the device according to the invention seen in plan view in the direction of the single crystal central longitudinal axis;
Fig. 3
a schematic representation of the cooling step of the method according to the invention;
Fig. 4
is a schematic representation of a step of distributing the cooling lubricant on the cutting tool before the cut;
Fig. 5
a schematic representation of the step of separating; and
Fig. 6
a schematic representation of the cleaning step in the method according to the invention.

Wie aus den Fig. 2 ersichtlich ist, weist die erfindungsgemäße Vorrichtung in bekannter Weise die Halterung und die Vorschubeinrichtung für den Einkristall 1, sowie die Trennscheibe 2 mit dem Kernblech 2a und dem diamantkornbesetzten Rand 3 des Innenloches der Trennscheibe. Im Unterschied zu der bekannten Vorrichtung weist die erfindungsgemäße Vorrichtung eine erste Zuführeinrichtung 10 zum Zuführen von Kühl-Schmiermittel auf den Rand 3 des Innenloches und auf die Trennscheibe 2 auf, welche in Rotationsrichtung der Trennscheibe 2 gesehen austrittsseitig an der Position P2 nach dem Durchtritt.durch den Einkristall 1 vorgesehen ist. Die erste Zuführeinrichtung 10 für Kühl-Schmiermittel ist beispielsweise als Düse ausgebildet. Ferner ist eine zweite Zuführeinrichtung 11 für Reinigungsmittel austrittsseitig im Bereich des Innenlochs vorgesehen. Außerdem ist ebenfalls austrittsseitig eine Einrichtung 12 zum Zuführen von eines gasförmigen Mediums, insbesondere von Druckluft, auf die Trennscheibe 2 und insbesondere den Rand 3 vorgesehen.As can be seen from Fig. 2, the inventive Device in a known manner, the holder and the feed device for the single crystal 1 and the cutting disc 2 with the core sheet 2a and the diamond-trimmed edge 3 the inner hole of the cutting disc. In contrast to the known one The device according to the invention has a device a first supply device 10 for supplying cooling lubricant on the edge 3 of the inner hole and on the Cutting disc 2, which in the direction of rotation of the cutting disc 2 seen on the outlet side at position P2 after Passage. Through the single crystal 1 is provided. The first Feeding device 10 for cooling lubricants is for example designed as a nozzle. Furthermore, a second feed device 11 for cleaning agent on the outlet side in the area of the inner hole. It is also on the outlet side a device 12 for supplying a gaseous Medium, especially compressed air, on the cutting disc 2 and in particular the edge 3 is provided.

Der Betrieb der erfindungsgemäßen Vorrichtung und das erfindungsgemäße Verfahren ist aus den Figuren 3 bis 6 ersichtlich. Vor dem Schneid- bzw. Trennvorgang sind die Trennscheibe 2 und der Einkristall 1 voneinander getrennt. Dann wird der Einkristall 1 relativ zu der Trennscheibe 2 bewegt und diese tritt rotierend in das Material des Einkristalls 1 zum Trennen ein. Wie in Fig. 3 gezeigt ist, wird während des Trennvorganges über die Zuführeinrichtung 10 Kühl-Schmiermittel mit einem geringen Volumenstrom, d.h. mit geringer Geschwindigkeit v und geringem Druck p dem Rand 3, der den Schneidrand bildet, über die Zuführeinrichtung 10 zugeführt. The operation of the device according to the invention and the device according to the invention The method can be seen from FIGS. 3 to 6. The cutting disc is before the cutting or cutting process 2 and the single crystal 1 separated from each other. Then it will be the single crystal 1 moves relative to the cutting disc 2 and this occurs rotating in the material of the single crystal 1 Separate. As shown in Fig. 3, during the Separation process via the feed device 10 coolant-lubricant with a low volume flow, i.e. at slow speed v and low pressure p the edge 3, which the Forming cutting edge, fed via the feed device 10.

Als Kühl-Schmiermittel wird ein Kühl-Schmiermittel mit einem Zusatz verwendet, der die Oberflächenspannung σ des Kühl-Schmiermittels erhöht und somit die Benetzung des Kernbleches 2a verschlechtert. Dadurch kommt es zu einer schlechten Benetzung des Kernblechs 2a der Trennscheibe 2, und es bilden sich Tröpfchen 20 des Kühl-Schmiermittels an der Oberfläche des Kernbleches 2a. Ebenfalls während des Trennvorganges wird, wie in Fig. 4 gezeigt ist, Druckluft über die Druckluftquelle 12 auf den Rand 3 geblasen, wodurch die schlechte Benetzung ausgeglichen wird. Die Druckluft trägt weiterhin zur Bildung von Tröpfchen 20 und zur Verteilung derselben bei. Wie in Fig. 5 gezeigt ist, dringt während des Trennvorgangs die Trennscheibe 2 mit dem Rand 3 und den auf der Oberfläche des Kernblechs 2a entstandenen Tröpfchen 20 des Kühl-Schmiermittels in den Einkristall 1 zum Abtrennen eines Waferabschnitts 1a ein. Es wird ständig Luft und Kühl-Schmiermittel geringen Drucks p zugeführt. Die Tröpfchen 20 des Kühl-Schmiermittels auf dem Kernblech 2a nehmen für die Zeit des Schnittes das abgetragene Material auf und verteilen es auf dem Kernblech, ohne daß es zu einem Eintrocknen oder zu einer Berührung des Wafers kommt.A cooling lubricant with a Additive that uses the surface tension σ of the coolant-lubricant increases and thus the wetting of the core sheet 2a worsened. This results in poor wetting of the core sheet 2a of the cutting disc 2, and form it droplets 20 of the cooling lubricant on the surface of the core sheet 2a. Also during the separation process becomes, as shown in Fig. 4, compressed air via the compressed air source 12 blown onto the edge 3, making the bad Wetting is balanced. The compressed air continues to carry to form and distribute droplets 20 at. As shown in Fig. 5, penetrates during the separation process the cutting disc 2 with the edge 3 and on the surface of the core sheet 2a formed droplets 20 of the cooling lubricant into the single crystal 1 for separating a wafer section 1a a. There is always air and cooling lubricants low pressure p supplied. The droplets 20 of the Cooling lubricant on the core sheet 2a take time the cut material and distribute it on the core sheet without causing it to dry out or to touching the wafer.

Nach dem Trennvorgang wird der Einkristall 1 und der abgetrennte Wafer über die Vorschubeinrichtung von der Trennscheibe 2 wegbewegt, so daß Trennscheibe und Einkristall bzw. der getrennte Wafer voneinander getrennt sind, wie in Fig. 6 gezeigt ist. Jetzt wird die Reinigung und der Abtransport des auf dem Kernblech aufgestauten und in den Tröpfchen 20 eingeschlossenen Materials durchgeführt, indem Druckluft mit hohem Druck p über die Zuführeinrichtung 12 zugeführt wird und gleichzeitig Reinigungsmittel in ausreichender Menge und mit größerer Geschwindigkeit v über die Zuführeinrichtung 11 zugeführt wird. After the separation process, the single crystal 1 and the separated one Wafers over the feed device from the cutting disc 2 moved away so that the cutting disc and single crystal or the separated wafer is separated from each other, as in FIG. 6 is shown. Now the cleaning and the removal of the pent up on the core sheet and enclosed in the droplets 20 Material performed by using high pressure compressed air Pressure p is supplied via the feed device 12 and at the same time detergent in sufficient quantity and with greater speed v fed via the feed device 11 becomes.

Somit ist das erfindungsgemäße Verfahren ein zweistufiges Verfahren, bei dem während des Trennvorgangs die Kühlung des Trennwerkzeugs, das Verwirbeln des Kühlmittels, das Einschließen des abgetragenen Materials in die Kühl-Schmiermitteltröpfchen und das Verteilen und Speichern der Kühl-Schmiermitteltröpfchen mit dem abgetragenen Material unter Einwirkung der Fliehkraft erfolgt. In einer zweiten Stufe wird, nachdem der Einkristall von der Trennscheibe weggefahren ist, die Reinigung und der Abtransport abgetragenen Materials über hohen Luftdruck und ausreichend Kühl-Schmiermittelzufuhr vorgenommen. Das in der zweiten Stufe verwendete Reinigungsmittel kann identisch mit dem Kühl-Schmiermittel sein, es kann jedoch auch eine andere Substanz, wie z.B. Wasser sein. Somit können Kühl-Schmiermittel und Reinigungsmittel unterschiedliche Eigenschaften haben.The method according to the invention is thus a two-stage process Process in which the cooling of the Separating tool, swirling the coolant, trapping of the removed material into the coolant lubricant droplets and distributing and storing the coolant lubricant droplets with the removed material below Centrifugal force acts. In a second stage after the single crystal is moved away from the cutting disc is the cleaning and the removal of worn material over high air pressure and sufficient cooling lubricant supply performed. The one used in the second stage Detergent can be identical to the coolant-lubricant but it can also be another substance, e.g. water his. Thus, coolants and lubricants have different properties.

Bei dem erfindungsgemäßen Verfahren wird zum Kühlen und Schmieren sehr viel weniger Kühl-Schmiermittel benötigt als zum Reinigen und Abtransport des abgetragenen Materials. Ein qualitativ hochwertiger Schnitt läßt sich nur mit einer solch geringen Kühl-Schmiermittelmenge durchführen. Während des eigentlichen Trennvorganges wird die Kühl-Schmiermittelmenge auf die minimal erforderliche Menge eingestellt, um die Kühlung und Schmierung zu garantieren. Der Trennspalt ist frei und die Berührung zwischen Kernblech und Waferabschnitt wird vermieden. Bei der Reinigung ist jedoch ein wesentlich höherer Volumenstrom optimal. Diese Erfordernisse widersprechen sich. Die Kühlung und Reinigung wird daher zeitlich voneinander getrennt, da für beide Schritte unterschiedliche Volumenströme optimal sind. In the method according to the invention, cooling and Lubrication requires much less cooling lubricant than for cleaning and removing the removed material. On high quality cut can only be done with such a Apply a small amount of coolant and lubricant. During the actual Separation process is the amount of coolant-lubricant set to the minimum required amount to cool and guarantee lubrication. The separation gap is free and the contact between the core sheet and the wafer section becomes avoided. However, when cleaning is a much higher one Volume flow optimal. These requirements contradict yourself. The cooling and cleaning are therefore different from each other separated, because different volume flows for both steps are optimal.

Anstelle der Zuführung von Druckluft ist es auch möglich ein anderes Gas, z.B. Stickstoff zuzuführen.Instead of supplying compressed air, it is also possible to use a other gas, e.g. Add nitrogen.

In einer bevorzugten Ausführungsform ist, wie in Fig. 2 gezeigt ist, zur Zuführung von Kühl-Schmiermittel zu der Zuführeinrichtung 10, die die geringe Menge an Kühl-Schmiermittel während des Trennvorgangs abgibt, ein Behälter 30 vorgesehen der sich in Arbeitsstellung in konstantem Abstand oberhalb der Zuführeinrichtung 10 befindet und der über eine Leitung 31 mit dieser verbunden ist. In dem Behälter befindet sich Kühl-Schmiermittel, welches der Zuführeinrichtung 10 über die Leitung nur unter dem Einfluß der Gravitation bzw. dem hydrostatischen Druck zugeführt wird. Luftblasen in der Leitung werden nach oben abgeführt. Somit wird gewährleistet, dass auch bei geringen zuzuführenden Mengen an Kühl-Schmiermittel die konstante und blasenfreie Zufuhr gewährleistet ist.In a preferred embodiment, as shown in FIG. 2 is for supplying cooling lubricant to the supply device 10, the small amount of cooling lubricant dispenses during the separation process, a container 30 is provided in the working position at a constant distance is located above the feed device 10 and the one Line 31 is connected to this. Located in the container coolant, which the feed device 10th via the line only under the influence of gravitation or is supplied to the hydrostatic pressure. Air bubbles in the Line are led upwards. This ensures that even with small amounts of coolant to be supplied ensures constant and bubble-free feeding is.

Die Erfindung ist zum Trennen verschiedenster Werkstoffe geeignet, z.B. für optische Gläser, Kunststoffe und andere.The invention is suitable for cutting a wide variety of materials, e.g. for optical glasses, plastics and others.

Claims (13)

  1. Device for separating materials, in particular single crystals, comprising
       a cutting disk (2) with a concentric hole whose edge (3) forms a cutting edge, the cutting disk (2) being rotatable about its central axis in order to cut the material (1),
       a positioning device for positioning the material (1) to be cut relative to the cutting disk in such a way that during cutting the cutting disk moves in rotating manner through the material to separate off a part (1a) of the material (1),
       a first device (10) for the supply of coolant-lubricant onto the cutting disk (2),
       and a second device (11) for the supply of a cleaning agent onto the cutting disk,
       characterised by further comprising a control system which actuates the first device (10) and the second device (11) in such a way that cooling and cleaning is performed separately in time by supplying coolant-lubricant during the cutting operation and cleaning agent after the cutting operation, after the part (1a) has been separated off from the material.
  2. Device according to Claim 1, wherein the control system is provided such that the cooling-agent is supplied at a low flow rate and cleaning agent is supplied at a higher flow rate relative to the latter.
  3. Device according to Claim 1 or 2, further comprising a third device (12) for supplying of a gaseous medium onto the cutting disk, wherein the third device (12) for supplying of a gaseous medium has a nozzle which is provided in such a way that the gaseous medium is supplied onto the edge (3).
  4. Device according to Claim 3, characterised in that the first device (10) for supply of coolant-lubricant and the third device (12) for the supply of a gaseous medium are arranged in such a way that the coolant-lubricant and the gaseous medium are supplied on the exit side behind the passage of the cutting disk (2) through the material (1).
  5. Device according to one of Claims 1 to 4, characterised in that the second device (11) for the supply of a cleaning agent, in particular of coolant-lubricant, is provided on the exit side.
  6. Device according to one of Claims 1 to 3, characterised in that the first device (10) for the supply of coolant-lubricant has a nozzle which is provided in such a way that the coolant-lubricant is applied onto the edge (3).
  7. Device according to one of Claims 1 to 6, characterised by a control system which actuates the first device (10) during the cutting operation in such a way that only a small quantity of coolant-lubricant is supplied.
  8. Device according to one of Claims 1 to 7, characterised in that in the working position above the first device (10) a storage container (30) for coolant-lubricant is provided which is connected to the first device via a conduit (31), wherein the supply results from the action of gravity.
  9. Method for separating materials, in particular for the inner hole cutting of single crystals, wherein a part (1a) of the material is separated off from the material (1) by means of a cutting disk (2) penetrating into the material by rotation during the cutting operation,
       characterised in that cooling and cleaning is separated from each other in time by a coolant-lubricant being supplied during the cutting operation and a cleaning agent being supplied after the cutting operation after the part (1a) has been separated off from the material,
       wherein the coolant-lubricant is supplied at a small flow rate and the cleaning agent is supplied at a greater flow rate relative to the latter.
  10. Method according to Claim 9,
       characterised in that, in the direction of rotation of the cutting disk, the coolant-lubricant is supplied only on the exit side behind the passage of the cutting disk (2) through the material (1).
  11. Method according to Claim 9 or 10, characterised in that a gaseous medium, in particular compressed air, is supplied to the edge of the cutting disk (2).
  12. Method according to one of Claims 9 to 11,
       characterised in that, in the direction of rotation of the cutting disk, the gaseous medium is supplied after the emergence of the cutting disk (2) from the material (1).
  13. Method according to one of Claims 9 to 12, characterised in that a coolant-lubricant containing an additive which increases the surface tension is employed.
EP01984580A 2000-11-08 2001-10-17 Device and method for separating materials Expired - Lifetime EP1224067B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10055286 2000-11-08
DE10055286A DE10055286A1 (en) 2000-11-08 2000-11-08 Monocrystal separating device based on annular sawing has device to supply gas to cutting disk
PCT/EP2001/012032 WO2002038349A1 (en) 2000-11-08 2001-10-17 Device and method for separating materials

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EP1224067A1 EP1224067A1 (en) 2002-07-24
EP1224067B1 true EP1224067B1 (en) 2004-07-28

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JP (2) JP4302979B2 (en)
CN (2) CN100396460C (en)
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CZ (1) CZ301194B6 (en)
DE (2) DE10055286A1 (en)
RU (1) RU2271927C2 (en)
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CN105049843B (en) * 2010-09-30 2018-02-06 三星电子株式会社 Enter the method and apparatus of row interpolation to image by using smooth interpolation wave filter
KR20120037576A (en) * 2010-10-12 2012-04-20 주식회사 엘지실트론 Sawing apparatus of single crystal and sawing method of single crystal
DE102011008400B4 (en) * 2011-01-12 2014-07-10 Siltronic Ag Method for cooling a workpiece made of semiconductor material during wire sawing
JP6722917B2 (en) * 2016-04-26 2020-07-15 三星ダイヤモンド工業株式会社 Scribe head unit

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FR1301500A (en) * 1960-08-19 1962-08-17 Hydrol Chemical Company Ltd Grinding machine
FR2557000B1 (en) * 1983-12-23 1987-08-07 Essilor Int GRINDING STATION FOR GRINDING MACHINE, PARTICULARLY FOR THE BEVELING OR GROOVING OF AN OPHTHALMIC LENS
DE3640645A1 (en) * 1986-11-28 1988-06-09 Wacker Chemitronic METHOD FOR SAWING CRYSTAL RODS OR BLOCKS BY MEANS OF INTERNAL HOLE SAWS IN THIN WINDOWS
JP2979870B2 (en) * 1992-11-27 1999-11-15 信越半導体株式会社 Method of cutting cone-shaped end of semiconductor ingot
DE4309134C2 (en) * 1993-03-22 1999-03-04 Wilfried Wahl Process for the lubrication and cooling of cutting edges and / or workpieces in machining processes
JPH06328433A (en) * 1993-05-20 1994-11-29 Tokyo Seimitsu Co Ltd Slicing machine
JPH07304028A (en) * 1994-05-13 1995-11-21 Nippon Steel Corp Slicing machine
SG70097A1 (en) * 1997-08-15 2000-01-25 Disio Corp Apparatus and method for machining workpieces by flushing working liquid to the tool-and-workpiece interface
US6386948B1 (en) * 1999-06-01 2002-05-14 Sumitomo Special Metals Co., Ltd. Magnet member cutting method and magnet member cutting

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CN100396460C (en) 2008-06-25
SK9782002A3 (en) 2002-12-03
TW590842B (en) 2004-06-11
JP2004512989A (en) 2004-04-30
RU2002118120A (en) 2004-01-20
DE10055286A1 (en) 2002-05-23
CN1394161A (en) 2003-01-29
CN101066616A (en) 2007-11-07
SK286415B6 (en) 2008-09-05
CZ301194B6 (en) 2009-12-02
US20030005919A1 (en) 2003-01-09
WO2002038349A1 (en) 2002-05-16
CZ20022365A3 (en) 2002-10-16
RU2271927C2 (en) 2006-03-20
EP1224067A1 (en) 2002-07-24
JP4302979B2 (en) 2009-07-29
ATE271962T1 (en) 2004-08-15
DE50102989D1 (en) 2004-09-02

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