EP1137514B1 - Modular machine for polishing and planing substrates - Google Patents

Abstract

The invention concerns a polishing machine comprising at least a base unit (10) in the form of a parallelepiped cell (12), with a first loading and unloading surface (14), a second opposite parallel surface (16) for access to the working zone located in an intermediate section (24), and third and fourth surfaces (18, 20). The loading pallet board (48) and unloading pallet board (56) are respectively borne by a loading arm (50) and an unloading arm (58) operating independently of each other, said pallet boards being both accessible on the first surface (14) side. The mechanism (28, 30) is located in the lower section beneath the cell (12) intermediate section (24), while the automaton is arranged in the top section, the mechanism and the automaton being accessible on the second surface (16) side.

Description

Technical field of the invention

The invention relates to a machine for polishing and planarizing substrates including the features contained in the preamble of claim 1.

State of the art

Document EP-A 774 323 describes a polishing machine of the kind mentioned, making use of a carousel mechanism to bring the substrates on a polishing table having a predetermined number of positions. The mechanism is located in the work area and above the polishing table. This results in risks of pollution of the substrates at the during polishing. Production must be stopped completely during maintenance or tool change operations on a given station. A such carousel machine is not expandable.

The document JP 63207559, on which the preamble of claim 1 is based, describes a modular machine for lapping substrates, which are stored in cassettes and extracted using a loading unit which sends them to two lapping units by through a transfer unit. After lapping, the substrate is mounted on a washing unit table, and is stored after cleaning in unloading unit cassettes.

Document US-A-4680893 relates to a polishing machine for semiconductor substrates, having a conventional non-modular structure, equipped with a swivel polishing arm with angular movement between a loading station, cleaning station, first station polishing station, a second polishing station, and a unloading.

Subject of the invention

The object of the invention is to provide a polishing machine modular, which is simpler and compact in comparison with the known machine.

The polishing machine according to the invention is defined in claim 1.

The polishing arm and the unloading can be pivotally mounted around a first vertical axis. The base unit has a rotary packaging head carried by a conditioning arm, which is pivotally mounted with the loading around a second vertical axis parallel to the first axis.

According to a preferred embodiment, a cleaning station is arranged between the two vertical axes, and between the polishing plate, and the first face of the cell so as to define a cleaning position for the polishing head, and concentric positions of the paddles loading, unloading, and polishing head during handling of substrates. The mechanism includes a geared motor housed in the lower compartment, and coupled to a rotating shaft extending in the direction of the first axis, said shaft driving a pulley and a belt transmission housed in the polishing arm for setting rotation of the polishing head. The rotating shaft extends inside a tubular column secured to the polishing arm and to a connecting rod maneuver, which is controlled by a first cylinder to ensure the pivoting of the polishing arm between the cleaning station and the polishing. The unloading arm is secured to a mounted socket coaxially around the column with the interposition of a tubular sheath, bearings being arranged between the sleeve and the sheath to allow a rotary movement of the unloading arm relative to the polishing arm. A control lever controlled by a second cylinder is secured to the socket to cause the angular movement of the unloading arm.

A similar mechanism is used to activate the conditioning arms and loading.

• module de polissage isolé utilisé en chargement manuel.
• module de polissage isolé équipé d'un module de chargement et d'un module de déchargement permettant de travailler en mode automatique sur une cassette de tranche complète.
• deux ou plusieurs modules de polissage juxtaposés avec transfert de tranche entre chaque module, ceci réalisant un procédé de polissage de type série sur les divers postes constituant l'équipement. Cet ensemble peut être équipé des modules de chargement et déchargement vers la cassette pour en faire un système automatique.
• deux ou plusieurs modules juxtaposés avec un système de chargement par robot liant les modules de polissage à un module de chargement/déchargement / transfert centralisé. Cette structure autorise tout type de parcours des pièces entre les différents modules de polissage. Chaque module de polissage est configuré sur un procédé élémentaire donné, le pilotage de la machine organise le parcours des tranches pour respecter les étapes de polissage successives (et de mesure éventuelle) définies par l'utilisateur. La même étape élémentaire de polissage peut être affectée à plusieurs modules de polissage pour optimiser la productivité globale de la machine.

The complete machine, configured at the user's request, can have very different structures:

• insulated polishing module used for manual loading.
• insulated polishing module equipped with a loading module and an unloading module allowing to work in automatic mode on a complete slice cassette.
• two or more polishing modules juxtaposed with transfer of wafer between each module, this carrying out a polishing process of series type on the various stations constituting the equipment. This set can be fitted with loading and unloading modules to the cassette to make it an automatic system.
• two or more modules juxtaposed with a robot loading system linking the polishing modules to a centralized loading / unloading / transfer module. This structure allows any type of path of the parts between the different polishing modules. Each polishing module is configured on a given elementary process, the control of the machine organizes the path of the wafers to respect the successive polishing steps (and possible measurement) defined by the user. The same basic polishing step can be assigned to several polishing modules to optimize the overall productivity of the machine.

The polishing modules are built without any mechanics in the polishing area to limit all risks of pollution.

Brief description of the drawings

• la figure 1 est une vue schématique en plan d'une unité de base de la machine de polissage selon l'invention;
• la figure 2 montre une vue selon la flèche 2 de la figure 1;
• la figure 3 représente l'unité de base de la figure 1 avec des modules de chargement et de déchargement individuels;
• la figure 4 montre une variante de la figure 3;
• la figure 5 est une vue à échelle agrandie et en coupe selon la ligne 5-5 de la figure 1;
• les figures 6 et 7 montrent un équipement à deux unités de base et à module de transfert, respectivement coulissant et pivotant;
• la figure 8 représente un (équipement multipostes à quatre unités en ligne, commandées par un robot;
• la figure 9 est une variante d'équipement de la figure 8;
• la figure 10 est une vue retournée selon la flèche 10 de la figure 8.

Other advantages and characteristics will emerge more clearly from the description which follows of an embodiment of the invention, given by way of nonlimiting example and represented in the appended drawings in which:

• Figure 1 is a schematic plan view of a base unit of the polishing machine according to the invention;
• Figure 2 shows a view along arrow 2 of Figure 1;
• Figure 3 shows the base unit of Figure 1 with individual loading and unloading modules;
• Figure 4 shows a variant of Figure 3;
• Figure 5 is an enlarged view in section along line 5-5 of Figure 1;
• Figures 6 and 7 show equipment with two base units and transfer module, respectively sliding and pivoting;
• FIG. 8 represents a (multi-station equipment with four units in line, controlled by a robot;
• Figure 9 is a variant of equipment of Figure 8;
• FIG. 10 is an inverted view according to arrow 10 in FIG. 8.

Description of a preferred embodiment

In Figures 1 and 2, a base unit 10 of a polishing and planarization of substrates, comprises a parallelepipedic cell 12 having a first face 14 for loading and unloading, a second face 16 opposite parallel for access to work and control areas, and third and fourth faces 18, 20 formed by solid walls not accessible, perpendicular to the first and second faces 14, 16.

The interior of a cell 12 is subdivided into three compartments 22, 24, 26 superimposed, comprising a lower compartment 22 for housing the drive mechanisms 28, 30, an intermediate working compartment 24, and an upper compartment 26 containing an automaton 34 of command and control of the operating cycle of the base unit 10.

The working compartment 24 is accessible from the second face 16 by a door 36, and contains a rotary polishing plate 38 equipped on its face upper of a fabric for receiving the liquid abrasive product. The fabric is polyurethane base, but any other material can be used to be soaked with abrasive liquid. Above the polishing plate 38 of form circular is arranged a polishing head 40 provided with a rack 42 intended applying a substrate to the polishing plate 38. The polishing head 40 is carried on a polishing arm 44, which is pivotally mounted around a first vertical axis 46 with a predetermined angular offset. The rack 42 of the substrate is rotated by means a belt transmission 43 integrated in the arm 44, and described in detail thereafter with reference to FIG. 5.

The polishing head 40 can be actuated in vertical translation according to the direction of arrow F1 between a raised position and a lowered position. In the raised position, the substrate is not in contact with the platen polishing 38 (case of Figure 2).

The actuation of the polishing head 40 towards the lowered position occurs by pneumatic or hydraulic control (not shown) controlled from an energy accumulator 32 housed in the compartment lower 22. In this lowered position, the substrate bears against the polishing plate 38, and undergoes the polishing cycle according to the parameters recorded in the controller 34. The routing of the substrate to the head of polishing 40 intervenes by means of a loading pallet 48 carried by a movable loading arm 50, which is pivotally mounted around a second vertical axis 52 parallel to the first axis 46, and separated from it the latter by a cleaning station 54. The loading arm 50 is capable of occupying a position A for loading the pallet 48 and a position B for transfer to the cleaning station 54.

The polishing arm 44 can also be moved to position B of the cleaning station 54 for recovering the substrate conveyed by the arm of loading 50, and to bring back the polished substrate at the end of the polishing cycle. The polished substrate is then evacuated to an unloading pallet 56 carried by an unloading arm 58, which is articulated on the first axis vertical 46 between an unloading position C for the pallet 56, and the transfer position B on the cleaning station 54.

The regeneration of the fabric on the polishing plate 38 occurs after one or more several polishing cycles by means of a conditioning head 60 rotary, carried by a movable conditioning arm 62, which is mounted at pivoting around the second vertical axis 52 between a rest position D, and a working position E. In the rest position D shown in the Figure 1, the conditioning head 60 is waiting outside the surface polishing. The transition to the working position E is carried out by pivoting of the conditioning arm 62 anticlockwise a watch, followed by the descent of the conditioning head 60 onto the polishing plate 38. The rotation of the conditioning head 60 removes the polishing particles, which are discharged to a drain pan (not shown).

The injection of liquid abrasive products takes place above the polishing 38 by means of supply ducts attached to the head polishing 40 or at the edge of the tank, and connected to a container in the lower compartment 22. Solenoid valves and pumps are controlled by PLC 34 to control the start-up or stop of the flow abrasive liquid on the polishing plate 38.

The substrates are constituted, for example, by semiconductor wafers of cylindrical shapes, in particular based on silicon. It's clear that the invention can be applied to any other field of chemical mechanical polishing.

The operation of the base polishing unit 10 is as follows:

The operator opens the doors on the side of the first face 14 to install a sample on the loading pallet 48. The doors are closed then followed by locking the sample on the loading pallet 48, and a pivoting of the polishing arm 44 to bring the head 40 into the position B on the cleaning station 54. The loading arm 50 pivots around the axis 52 towards the cleaning station 54 to position the pallet loading 48 under the head 40. After unlocking the sample from the loading pallet 48, the polishing head 40 is actuated automatically to the lowered position for gripping the sample. The head 40 then returns to the raised position, followed by the return of the polishing arm 44 to the working position on the polishing plate 38. The polishing of the sample can then start after injection of the liquid abrasive products. The loading arm 50 reposition the pallet 48 in position A to authorize the loading of the next sample.

At the end of the polishing cycle of the first sample, and of the rinsing on the tray 38, the head 40 is moved to the raised position, followed by movement of the polishing arm 44 towards position B on the station cleaning 54. After actuation of the head towards the lowered position, the polishing head 40 and polished sample assembly is rinsed with jets of water. The head 40 then returns to the raised position, and the arm of unloading brings the unloading pallet 56 to position B under the head 40. The sample is then deposited and locked on the pallet of unloading 56, and the unloading arm 58 reposition the pallet 56 in position C.

The polishing head 40 descends into the lowered position to be cleaned in cleaning station 54, then returns to the raised position, ready to enter the second sample presented on the loading pallet 48 after pivoting of the loading arm 50 towards position B. The rest of the process is identical to that described previously. The work of regeneration of the tissue on the tray 38 by means of the head 60 rotary packaging can intervene during the polishing operation, or when the polishing head 40 is in the cleaning station 54. It just move the conditioning arm 62 to position E to remove the polishing particles from the plate 38.

• un module de chargement individuel robotisé,
• un module de déchargement individuel robotisé,
• un module de transfert inter-poste de polissage ;
• un système intégré de chargement / déchargement avec gestion centralisée du flux des substrats.

To the base unit 10 with manual loading described with reference to FIGS. 1 and 2, can be added additional modules allowing to work in automatic mode for the circulation of substrates or samples. The different modules that can be associated with a base unit 10 are the following:

• an individual robotic loading module,
• an individual robotic unloading module,
• an inter-polishing transfer module;
• an integrated loading / unloading system with centralized management of the flow of substrates.

In FIG. 3, an individual loading module 64 is juxtaposed with the first face 14 of the base unit 10, opposite the loading pallet 48.

The module 64 comprises a loading cassette 66 containing a plurality of polishing samples stored in the individual cells. A handling system 68 is mounted on the fixed support 69 to extract the samples from cassette 66, and the carriers individually on the loading pallet 48. The loading module 64 is activated by the automaton 34 following a request for a sample sent by the post of polishing. The samples are arranged vertically extending parallel to the face 14 of the base unit 10.

• déplacement du système de manipulation 68 vers l'échantillon à polir se trouvant dans une alvéole prédéterminée de la cassette de chargement 66,
• extraction de l'échantillon, et orientation de l'échantillon de manière à positionner la face à polir vers le bas,
• transfert de l'échantillon vers la palette de chargement 48 selon un mouvement de translation perpendiculaire à la face 14,
• dépose de l'échantillon sur la palette de chargement 48,
• retrait du système de manipulation 68 et positionnement vers le prochain échantillon à polir.

The operating cycle of the loading module 64 comprises the following successive steps:

• displacement of the handling system 68 towards the polishing sample located in a predetermined cell of the loading cassette 66,
• extraction of the sample, and orientation of the sample so as to position the face to be polished down,
• transfer of the sample to the loading pallet 48 in a translational movement perpendicular to the face 14,
• depositing the sample on the loading pallet 48,
• removal of handling system 68 and positioning towards the next sample to be polished.

An individual unloading module 70 is placed next to the loading 64, and opposite the unloading pallet 56. The module unloading 70 is identical to loading module 64, and comprises a cassette 72 for receiving the samples after polishing, and a support 74 cassette to keep the cassette submerged. A system of handling 76 identical to that of loading module 64, is capable of extracting the samples from the unloading pallet 56, and place them vertically in the receiving cassette 72 in the cells predetermined extending parallel to the face 14.

• déplacement du système de manipulation 76 vers la palette de déchargement 56,
• extraction d'un échantillon poli entreposé sur la palette 56,
• transfert de l'échantillon vers la cassette de réception 72, et dépose dans une alvéole de ladite cassette,
• déplacement du système de manipulation 76 vers une position d'attente.

The operating cycle of the unloading module 70 comprises the following successive steps:

• displacement of the handling system 76 towards the unloading pallet 56,
• extraction of a polished sample stored on the pallet 56,
• transfer of the sample to the reception cassette 72, and deposit in a cell of said cassette,
• displacement of the handling system 76 towards a waiting position.

In the variant of Figure 4, the samples instead of being arranged vertically, are stored horizontally in the cassettes 66, 72 respective loading and unloading modules 64, 70. The operation of the cycles is identical to that described previously in reference to figure 3.

In Figure 5, the drive mechanism 28 comprises a geared motor housed in the lower compartment 22 and mechanically coupled to a rotary shaft 78 extending along the vertical axis 46 inside a tubular column 80 secured to the polishing arm 44. Bearings 82, 84 are arranged between the shaft 78 and the column 80, and the upper end splined 85 of the rotary shaft 78 is fixed to a pulley 86 associated with the belt transmission 43 of the polishing head 40. The belt 43 extends perpendicular to the vertical axis 46, inside the polishing arm 44, and the column 80 rotates around the shaft 78 during the pivoting of the arm of polishing 44 under the action of an operating rod 88 controlled by a first cylinder (not shown). The unloading arm 58 is secured to a socket 90 mounted coaxially around the column 80 with interposition of a tubular sheath 92. 94.96 bearings between the socket 90 and furnace 92 allow relative pivoting movement of the arm unloading 58 with respect to the polishing arm 44. The travel angle of the unloading arm 58 is operated by means of a lever control 98 subject to socket 90, and capable of being actuated by means a second cylinder (not shown). The height adjustment of the polishing 44 is ensured by an adjustment device 100 with tie rods 102.

The drive mechanism 30 with vertical axis 52 of the arm of packaging 62 and loading arm 50 is of the same type as that described with reference to Figure 5.

With reference to FIG. 6, an inter-station transfer module 104 cooperates with two base units 10, 10A joined to one another by their faces 18, 20 respective. A charging module 64 is associated with the base unit 10, and an unloading module 70 is associated with the other adjacent unit 10A. The transfer module 104 is interposed between the two modules 64, 70, and allows in the same polishing action to perform an operation in two steps. The transfer module 104 comprises a slide 105 intended to be move in translation to take a sample on the pallet unloading 56 from unit 10, and put it on the loading pallet 48 of unit 10A.

FIG. 7 shows another version of the transfer module 106 using a arm 108 pivoting between two extreme positions located vertically pallets 56, 48 respectively of units 10, 10A.

Figure 8 shows multi-user equipment, which consists of four base units 10, 10A, 10B, 10c arranged in line, and cooperating with a robot 110 moving in translation along the aligned faces 14 of the different units 10, 10A, 10B, 10C. The robot 110 ensures the connection of the units with a centralized 112 loading / unloading module, placed in front the base unit 10. The loading / unloading module 112 makes it possible to work with two loading cassettes and two unloading. Thanks to access protections, it is possible to unload and change the set of tapes that was polished while the next set is during work. This avoids waiting for the complete emptying of the machine to relaunch on the next production, thereby resulting in a gain of productivity.

The samples are transported in a wet tunnel 114 by spraying of water to protect the samples. Each base unit 10, 10A, 10B, 10C is autonomous thanks to the integration of its own elements of loading and unloading. By the independence of the unit from transfer robot 110, the unit maximizes its time available for the polishing for increased productivity.

Control of the assembly by a supervision system (not shown) allows flexible configuration of the machine. Total freedom is left in the assignment of each station to a given polishing operation, as well as defining the list of operations to be performed on each sample. Reconfiguration is automatic, when, for an event intervening during production, a polishing station becomes unavailable. In this case, the machine management organizes the flow of samples to account for this new situation, and continue the production in this new context.

The mechanical structure of each station allows access to a unit of base previously declared unavailable for maintenance operations without this representing a risk for the intervener. In particular, it is possible to change the polishing plate 38, or a polishing head 40, or packaging 60, while production continues on the rest of the machine. The result is an increase in overall productivity of equipment.

Figure 9 shows a variant of multi-user equipment in which the two base units 10B, 10C are arranged facing the other two units 10, 10A with interposition of the transfer robot 110.

It is clear that a different number of base units can be used depending on number of samples, and desired polishing cycles.

Figure 10 shows the rear view of the multi-user equipment in Figure 8. The base units 10, 10A, 10B, 10C have no mechanism in the intermediate compartment where polishing takes place, so that avoid any risk of pollution. All of the mechanics and the system pneumatic is integrated in the lower compartments 22 of the units. All the handling faces 16 are thus accessible for the change of tools, and of the consumable fabric of the polishing plates 38.

Claims (15)

1. A machine for polishing and planing substrates, comprising at least one base unit (10, 10A, 10B, 10C) in the form of a parallelepipedic cubicle (12) having :

   a first surface (14), a third and a fourth surfaces (18, 20) comprising solid transverse walls extending perpendicularly to the first surface (14), said base unit comprising:

   at least one rotary polishing plate (38) on which a substrate is polished,

   a polishing head (40) mobile in translation between a raised position and a lowered position and provided with a bearing element (42) for support of the substrate,

   a pivoting polishing arm (44) designed to move the polishing head (40) to pick up the substrate to be polished from the loading pallet (48) and to convey it onto an unloading pallet (56) after polishing,

   at least one mechanism (28, 30) for driving the polishing plate (40) and the bearing element (42) of the polishing head (38) in rotation (28), and for alternate movement of the polishing arm (44) and of the loading and unloading pallets (48, 56), supported respectively by a loading arm (50) and an unloading arm (58) with operations independent from one another,

   and a controller (34) for control of the mechanism (28, 30) during the polishing cycle,

   characterized in that

   the first face is a loading and unloading face,

   a second opposite surface (16) of the base unit (10, 10A, 10B, 10C) at the opposite of the first face (14) gives access to the working zone situated in the intermediate compartment (24),

   the mechanism (28, 30) is situated in the bottom compartment (22) underneath the intermediate compartment (24) of the cubicle (12), whereas the controller (34) of the base unit (10) is located in the upper compartment (26), the mechanism (28, 30) being accessible on the side where the second surface (16) is situated, and the pallets (48, 56) both being accessible on the side where the first surface (14) is situated.

   a cleaning station (54) is arranged between the polishing plate (38) and the first surface (14) of the cubicle (12), so as to define a cleaning position of the polishing head (40) and concentric positions of the loading pallet (48) and unloading pallet (56) and of the polishing head (40) when substrate handling operations are performed.
2. The polishing and planing machine according to claim 1, characterized in that the polishing arm (44) and the unloading arm (58) are pivotally mounted around a first vertical axis (46).
3. The polishing and planing machine according to claim 2, characterized in that the base unit (10, 10A, 10B, 10C) comprises a rotary conditioning head (60) supported by a conditioning arm (62), which is pivotally mounted with the loading arm (50) around a second vertical axis (52) parallel to the first axis (46).
4. The polishing and planing machine according to claim 2, characterized in that the mechanism (28) comprises a geared motor housed in the bottom compartment (22) and coupled to a rotary shaft (78) extending in the direction of the first axis (46), said shaft (78) driving a pulley (86) and a belt-driven transmission (43) housed in the polishing arm (44) to move the polishing head (40) in rotation.
5. The polishing and planing machine according to claim 4, characterized in that the rotary shaft (78) extends inside a tubular column (80) securedly united to the polishing arm (44) and to an operating rod (88), which is controlled by a first jack to perform pivoting of the polishing arm (44) between the cleaning station (54) and the polishing plate (38).
6. The polishing and planing machine according to claim 5, characterized in that the unloading arm (58) is securedly united to a sleeve (90) mounted coaxially around the column (80) with a tubular sheath (92) interposed, bearings (94, 96) being arranged between the sleeve (90) and the sheath (92) to allow a rotary movement of the unloading arm (58) with respect to the polishing arm (44).
7. The polishing and planing machine according to claim 6, characterized in that an operating lever (98) controlled by a second jack is securedly united to the sleeve (90) to bring about the angular movement of the unloading arm (58).
8. The polishing and planing machine according to one of the claims 1 to 7, characterized in that an individual loading module (64) is juxtaposed with the first surface (14) of a base unit (10) facing the loading pallet (48), said module (64) having a loading cassette (66) containing a plurality of samples arranged horizontally or vertically.
9. The polishing and planing machine according to one of the claims 1 to 8, characterized in that an individual unloading module (70) is juxtaposed with the first surface (14) of the base unit (10, 10A) facing the unloading pallet (56), said module having a receipt cassette (72) for receipt of the polished substrates, which can be arranged horizontally or vertically.
10. The polishing and planing machine according to one of the claims 1 to 9, characterized in that an inter-station transfer module (104, 106) operates in conjunction with two base units (10, 10A) adjoined to one another by their respective transverse faces (18, 20), to perform a polishing operation in two stages after transfer from the unloading pallet (56) of one of the units (10) to the loading pallet (48) of the other unit (10A).
11. The polishing and planing machine according to claim 10, characterized in that the transfer module (104) comprises a slide (105) movable in translation between the two units (10, 10A).
12. The polishing and planing machine according to claim 10, characterized in that the transfer module (106) comprises an arm (108) pivoting between the unloading pallet (56) of the unit (10) and the loading pallet (48) of the other unit (10A).
13. The polishing and planing machine according to claim 1, characterized in that several base units (10, 10A, 10B, 10C) are associated with a loading / unloading module (112) and operate in conjunction with a programmed robot (110) moving in translation along aligned surfaces (14) of the different units, and inside a wet tunnel (114) with water projection.
14. The polishing and planing machine according to claim 13, characterized in that the base units (10, 10A, 10B, 10C) are arranged in-line.
15. The polishing and planing machine according to claim 13, characterized in that the base units (10, 10A) are arranged in tandem with other units (10B, 10C) to define an intermediate corridor for passage of the robot (110).

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