EP0813943A2 - Cutting center - Google Patents

Abstract

The cutting centre for producing ingots comprises connected in the same assembly first device (23) for carrying out the necessary operations (24) for the production of packaged sections for later use. The operations are managed and connected together by a second device (25) so as to form sub groups (26). These sub groups are themselves connected by third means (27) comprising storage, handling and transport systems. A transfer chain is thus formed in which all the operations and means are compatible and interconnected. The second device for managing the necessary operations are constituted by a computer operated multi-axis robot which carries out all the operations of fixing the piece on a support ready to be mounted on the cutting system. The cutting unit comprises an abrasive saw or a saw with several diamond blades. The packaging unit comprises a packaging system for placing the cut sections into cassettes.

Description

The present invention relates to a slicing center for producing slices from pieces to be sliced.

The manufacture of wafers from ingots is generally done according to a series of successive stages grouping in an erratic way a certain number of machines or devices more or less well matched, generally manufactured to achieve a very precise function, but without interface thought previous or subsequent operations. Integration is generally carried out by the user with more or less difficulty or success and with more or less automation.

When cutting into thin slices of materials in the form of ingots, a certain number of operations must be carried out and the slices obtained must be put in a packaging which makes it possible to subsequently treat them without restriction according to the needs of the user. The difficulty of integrating operations depends on the methods used for slicing.

From the obtaining of the part to be cut, generally in the form of an ingot, the following operations must be carried out. The ingots are fixed on a support in a position which must be very precise, if it is a single crystal where the orientation of the crystal structure has a role to play. In this case, a determination of the orientation must be made by X-rays for example and a positioning is necessary. Once the piece to be sliced positioned and fixed on its support, the latter is mounted on the slicing device which can be a diamond saw or a wire saw or any other means enabling the material to be cut either in bundles or pieces by room. A coarse cleaning operation and packaging of the slices obtained will then follow. This conditioning is generally done in a packaging which keeps each slice separate from the next one to avoid any contact between them which could cause chipping. This type of packaging is called a cassette and is used to transport the wafers for subsequent operations.

Each of the above operations requires first means to be carried out.

All the operations between the ingot and the conditioned wafers are currently done independently with the first means and with a strong manual participation, therefore of manpower, from where a high economic cost.

The object of the present invention is to remedy these drawbacks and it is characterized, for this purpose, by the fact that the slicing center comprises, assembled in the same set of first means, for carrying out the operations necessary for the production of the slices conditioned subsequent use from pieces to be cut and by the fact that these operations are managed and linked together by second means so as to form sub-groups and by the fact that these sub-groups are themselves linked together by third means thus forming a transfer chain in which all the operations and all the means are compatible and interconnected to form the cutting center.

Thanks to these characteristics, the wafers can be produced in an automated manner with a very high yield, with increased reliability and security, with uniform and excellent quality and at a lower cost price.

Integration into subgroups by second means and then full integration, by third means, of individual protection operations made up of the first means can be carried out in such a way as to make the whole almost automatic, therefore replacing a series of well separated steps, difficult for the user to coordinate, by a single operation which consists in putting back pieces to be sliced or ingots and receiving in return slices conditioned in a pre-selected packaging. It is therefore a question of providing the user with an automatic or semi-automatic slicing center according to a global concept of slice manufacturing.

The implementation of the overall concept overcomes the drawbacks of the multiple stages currently required for the manufacture of wafers from the ingot to the conditioned wafer by providing an overall concept integrating all of the operations required, therefore the first means. The user then no longer has to worry about making each operation compatible with the next, this being carried out by the second and / or third means.

To meet the principle of global concept, we can group a certain number of operations, therefore first means, in sub-groups which each carries out for them, via the second means, part of the chain, then connect them to each other by third means in order to give the whole the chain character of transfer and thus satisfy the overall concept principle of a slicing center.

• 1) unité de fixation de la pièce à trancher ou du lingot et orientation en position si nécessaire,
• 2) unité de tranchage constituée de un ou plusieurs dispositifs de tranchage,
• 3) unité de conditionnement constituée de un ou plusieurs dispositifs de conditionnement,
• 4) opérations subséquentes selon choix de l'utilisateur.

The subgroups can be serialized as follows:

• 1) unit for fixing the workpiece or ingot and positioning in position if necessary,
• 2) slicing unit consisting of one or more slicing devices,
• 3) packaging unit consisting of one or more packaging devices,
• 4) subsequent operations according to the user's choice.

The ingot or the piece to be cut, as well as its spatial orientation with possible control of the crystal by X-rays or by an optical method, can be carried out by second means in the form of a robot managed by computer and coordinating the orientation and fixing operations in position, as well as the location of ingots. The first means being in this case constituted inter alia by the fixing stations, the R-X measuring station, possibly a cleaning station, the list not being exhaustive.

The placement in the slicing unit of the pieces to be sliced can also be achieved by second means in the form of a robot manipulator always computer controlled and always keeping track of the workpiece. Once sliced, the part to be sliced can be taken up by the same manipulator robot to be transferred to the packaging unit. This operation is generally only necessary when slicing into a package by a wire saw or multi-blade for example. In the case of a piece-by-piece slicing, the slices will be taken directly one after the other from the slicing unit to be packaged in the packaging unit. The first means of the slicing unit can consist of a set of one or more free or fixed abrasive slicing devices, such as wire saws, diamond or multi-blade saws.

The packaging unit will receive the slices either in the form of pieces sawn into slices, but always attached to each other generally by a glued heel, or either in the form of separate slices but also having an adherent heel. The packaging unit will therefore have to distribute the slices in containers called cassettes and now these separate from one another. The packaging unit can also have a role of cleaning the edges or removing the heel, but can also insert other operations such as chamfering or marking or even control and scrap operations which each represents one of the first means, the second means can for example consist of conveyor belts connecting the various first means to each other.

Once out of the packaging unit, the attachment to other operations is only a question of user choice since these operations are generally well known and practically all use slices put in packaging. in the form of cassettes.

• 1) stockage d'entrée qui reçoit les lingots prêts pour être tranchés,
• 2) premier stockage intermédiaire après montage et orientation éventuelle et avant tranchage,
• 3) deuxième stockage intermédiaire après l'unité de tranchage et avant l'unité de conditionnement,
• 4) stockage de sortie après l'unité de conditionnement et avant les opérations subséquentes définies par l'utilisateur.

To link the different sub-groups and make them a unit, it is possible, but not always absolutely necessary, to create intermediate storage facilities which constitute the third means in part. The following intermediate storage can therefore be considered:

• 1) entry storage which receives the ingots ready to be sliced,
• 2) first intermediate storage after assembly and possible orientation and before slicing,
• 3) second intermediate storage after the slicing unit and before the packaging unit,
• 4) outlet storage after the packaging unit and before the subsequent operations defined by the user.

The passage between the different subgroups consisting of the first and second means through intermediate storage can be achieved by independent robotics and separate from the second means. This independent robotics then constitutes with intermediate storage the third means. However and in many cases, the second means are sufficient to ensure the transfer and the operations and functions of the third means can then be carried out entirely. or only partially by the second means or integrated into them.

Thus, the invention allows the slicing unit by the overall concept of slicing to become a slicing center and thus avoid the multiple steps which require a significant workforce and the difficulties of keeping track of each piece to be cut. The slicing center therefore consists of first means for carrying out the necessary operations, second means making it possible to manage a series of operations between them and thus constituting a sub-group of operations, and third means linking the sub-groups together. to make a single transfer chain called a slicing center.

Other advantages emerge from the characteristics expressed in the dependent claims and from the description setting out the invention below in more detail with the aid of drawings which schematically represent examples of embodiments.

Figure 1 is a slicing center flowchart.

Figure 2 shows a variant.

Figure 3 shows the general principle of hierarchical organization of a slicing center.

FIG. 4 illustrates by means of a flowchart an exemplary embodiment of the organization of another slicing center.

FIG. 1 shows a possible flow diagram for carrying out the present invention with the various possible intermediate storages. The slicing piece 1 is stored in an input storage 2. The robot 3 of the positioning unit 4 positions it after having possibly measured it, on the RX generator 6. Then the part to be sliced 1 positioned on the support 5 is put on hold in the first intermediate storage 7. The slicing piece 1 is then taken up by the manipulator 9 of the slicing unit 10 mounted on a rail 8 and introduced into the slicing device 11, in this case a wire saw. After slicing, the slices 12 still adhering to the support 5 are put on hold in the second intermediate storage 13 before being taken up by a new manipulator 14 to be introduced into the packaging unit 30 comprising the packaging device 15. The slices 12 mounted on their support 5 are presented one after the other by the motor 16 in front of a saw blade 17 which cuts the heel which retains the slices 12. These will therefore fall on the conveyor 18 and will be introduced one after the others in the cassette 19 which moves downwards thanks to the motor 20. The cassettes once full will be transported by a conveyor belt in the outlet storage 22.

Figure 2 gives a plan view of a possible variant of cutting center. The pieces to be cut 1 are stored in an input storage 2. The robot 3 of the positioning unit 4 positions, after having possibly measured it on the RX generator 6, the piece to be cut 1 on the support 5 in the assembly station 29. It is then put on hold in the first intermediate storage 7. The part to be cut is then taken up by the manipulator 9 of the slicing unit 10 mounted on a rail 8 and introduced into one of the slicing devices 11 six in number in this example. After slicing, the slices 12 still adhering to the support 5 are put on hold in the second intermediate storage 13 before being taken up by a new manipulator 14 to be introduced into one of the two packaging devices 15 which constitute the unit for packaging 30. The slices 12 once separated from their support are transported by the conveyor 18 and then placed in cassettes 19. The cassettes 19 are transported by conveyor belts 21 to the outlet storage 22.

Figure 3 shows a possible schematic flowchart of a slicing center. The first means 23 are grouped into operations 24. The second means 25 manage a certain number of operations 24 and form sub-groups 26. These are linked together by the third means 27 to form the cutting center 28.

FIG. 4 illustrates a practical example of a flow diagram of an embodiment of the slicing center 28.

• un générateur R-X 23a1 pour effectuer l'opération 24a1 de détermination de l'orientation cristallographique,
• quatre stations de montage 23a2 pour effectuer l'opération de collage 24a2 de la pièce à trancher sur un support à usage unique dans une orientation prédéterminée,
• une station de fixation 23a3 pour obtenir l'opération de fixation 24a3 de la pièce à trancher avec son support à usage unique sur une plaque de support de la machine à trancher.

The first means 23a1 to 23a3 of the positioning unit 26a include:

• an RX generator 23a1 for performing the operation 24a1 for determining the crystallographic orientation,
• four assembly stations 23a2 for carrying out the bonding operation 24a2 of the piece to be cut on a single-use support in a predetermined orientation,
• a fixing station 23a3 to obtain the fixing operation 24a3 of the piece to be cut with its support single use on a slicing machine support plate.

These different operations are managed and linked together by second means 25a, constituted for example by a robot to form the sub-group 26a corresponding to the positioning unit.

The slicing unit 26b comprises as first means six slicing machines 23b1, which are for example wire saws performing the slicing operation 24b1, and a shower 23b2 for carrying out a pre-cleaning operation 24b2.

The connection between these two operations is carried out by second means 25b constituted by a rail manipulator to form a second subgroup 26b.

The sawn slices which always adhere by a heel to their disposable support are then treated in the packaging unit forming the sub-group 26c.

• deux scies à ruban ou à disque 23c1 effectuant l'opération de séparation 24c1 de la tranche du support à usage unique,
• deux élévateurs à cassette 23c2 pour obtenir l'opération de mise en cassette 24c2 , et
• un nettoyeur 23c3 à jet de liquide de nettoyage pour effectuer une opération de nettoyage 24c3 des tranches séparées.

The latter includes as first means:

• two band or disc saws 23c1 performing the operation of separating 24c1 from the edge of the single-use support,
• two 23c2 cassette elevators to obtain the 24c2 cassette operation, and
• a cleaner 23c3 with a jet of cleaning liquid for carrying out a cleaning operation 24c3 of the separate slices.

All of these operations can be managed by means of conveyor belts forming the second means 25c of the conditioning subgroup 26c.

The slicing unit 28 could possibly also be supplemented by a subsequent processing unit forming a sub-group 26d.

The first means of the latter may include a milling device 23d1 intended for the operation of removing the heel 22d1, a grinder 23d2 performing the chamfering 24d2, a polisher 23d3 and a lapping member 23d4 for polishing 24d3 and lappage 24d4 , a washing device 23d5 for carrying out a final washing 24d5, control and measuring devices 23d6 intended for quality control 24d6 and a device 23d7 intended for marking 24d7 of the slices obtained. All of these operations 24d1 to 24d7 can be connected by second means 25d constituted by manipulators and / or conveyors to obtain a continuous sequence forming the subsequent processing unit 26d.

The three or four units corresponding to the subgroups 26a to 26d are interconnected by the third means 27 to form a cutting center 28 forming a coherent whole. These third means comprise input storage members, intermediate between some or all of the sub-groups and output, and means of transport and handling comprising manipulating robots and / or conveyors. The various first, second and third means may be commanded and controlled in whole or in part by a central computer control unit 28A.

The overall concept of slicing through the integration of all functions from the workpiece to the conditioned slice allows for a whole simpler to use, more flexible and easier to manage. Due to the fact that its control can be entirely or partly computerized, the risk of error is minimized and makes the whole more reliable. Maximum performance, productivity and flexibility are thus obtained, without this being to the detriment of the quality of the slices produced.

Naturally other solutions to the overall concept of slicing can be envisaged which by their functions realize the integration of the functions necessary for obtaining a complete unit for the production of slices from the piece to be sliced up to the packaging in cassettes see even further. For example, the use of a single manipulator without intermediate storage can be envisaged. The different sub-groups of operations can be more or less automated.

The second means 25a to 25d can also perform some of the functions of the third means 27 and vice versa. Thus the robot of the positioning unit can also transport and direct the parts to be cut in the intermediate storage. The rail manipulator of the slicing unit can also transport the first intermediate storage to the slicing machines and the pre-cleaning shower to the second intermediate storage before the conditioning unit 26c. Other first means 23 and other operations 24 may be provided and integrated into the slicing center. Certain operations may be integrated into neighboring subgroups. Thus fixing 24a3 of the piece to be cut with its unique support on the plate machine support may be performed as part of subgroup 26b of the slicing unit. The pre-cleaning 24b2 can be deleted or integrated into the following subgroup 26c. The organs and the operations of mechanical preparations, namely the removal of the heel, the chamfering, the polishing and the lapping, and the operations of cleaning and final washing may also be integrated into the third subgroup 26c of conditioning. The choice of the number of each organ and device of the first, second and third means will be determined according to the desired production capacity.

Some of the first, second and third means can also be executed manually. It is of course also possible that certain operations described with reference to Figures 1,2 and 4 may be missing.

However, the solutions must retain the character of the overall concept of slicing by linking all of the operations, from the part to be sliced to the conditioned slice, in a single operation.

Claims (14)

Slicing center intended to produce slices (12) from pieces to be sliced (1), characterized by the fact that it includes together in the same set of first means (23) to carry out the operations necessary for the production of slices (12) packaged for later use from pieces to be cut (1) and by the fact that these operations are managed and linked together by second means (25) so as to form sub-groups (26) and by the fact that these sub-groups (26) are themselves linked together by third means (27) thus forming a transfer chain in which all the operations and all the means are compatible and interconnected to form the slicing center (28 ). Slicing center according to claim 1, characterized in that the sub-groups (26) formed by the first means (23) and managed by the second means (25) are at least three in number, namely a unit of positioning (4,26a), a slicing unit (10,26b) and a packaging unit (30,26c). Slicing center according to claim 2, characterized in that the packaging unit (30,26c) is connected to a fourth sub-group (26d) forming a final processing unit. Slicing center according to one of claims 1 to 3, characterized in that the functions of the third means (27) are executed at least partially by or integrated with the second means (25). Slicing center according to claim 2, characterized in that the second means (25) of the positioning unit (4,26a) are constituted by a multi-axis robot (3) managed by computer and performing all the operations between the part to be cut (1) and its fixing in oriented position on a support (5) ready to be mounted on a slicing device (11). Slicing center according to claim 2, characterized in that the slicing unit (10,26b) comprises at least one slicing device (11) which is a free abrasive saw or a saw with one or more diamond blades. Slicing center according to one of Claims 2 to 6, characterized in that the packaging unit (30,26c) comprises at least one packaging device (15,25c) for placing the slices in cassettes (19) (12) obtained. Slicing center according to claim 7, characterized in that the packaging device (15,25c) comprises at least one separation member (17,23c1) for separating the slices (12) from a heel to which they are attached, a conveying member (18) for bringing the wafers (12) to a cassette placing member (19,20) in which the slices (12) are introduced. Slicing center according to one of claims 2 to 8, characterized in that the packaging unit (26,30) comprises a device capable of carrying out cleaning operations. Slicing center according to one of claims 2 to 9, characterized in that it comprises devices intended to carry out mechanical preparations of the slices obtained integrated either in the packaging unit (30,26c) or in the unit final processing (26d). Slicing center according to claim 10, characterized in that the said devices for carrying out mechanical preparations comprise members for carrying out at least one of the operations consisting in removing the heel from the edge (12), in carrying out chamfering, polishing and / or a lappage. Slicing center according to one of Claims 3 to 11, characterized in that the final processing unit (26d) comprises members for performing at least one of the operations consisting in carrying out final cleaning, in quality control and / or a marking. Slicing center according to one of the preceding claims, characterized in that the third means (27) comprise at least one input storage device and / or one or more intermediate storage devices, and / or a final storage device, and / or transport and handling means comprising at least one handling robot and / or a conveyor. Slicing center according to one of the preceding claims, characterized in that the first, second and / or third means are at least partially controlled and controlled by at least one computer unit.

Images