FR2505713A1 - Semiconductor wafer carrying head for polishing machine - has circular disc covered in thin tissue with reduced pressure behind tissue to hold wafers - Google Patents
Semiconductor wafer carrying head for polishing machine - has circular disc covered in thin tissue with reduced pressure behind tissue to hold wafers Download PDFInfo
- Publication number
- FR2505713A1 FR2505713A1 FR8110182A FR8110182A FR2505713A1 FR 2505713 A1 FR2505713 A1 FR 2505713A1 FR 8110182 A FR8110182 A FR 8110182A FR 8110182 A FR8110182 A FR 8110182A FR 2505713 A1 FR2505713 A1 FR 2505713A1
- Authority
- FR
- France
- Prior art keywords
- disc
- tissue
- face
- rack
- polishing machine
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000005498 polishing Methods 0.000 title claims abstract description 27
- 235000012431 wafers Nutrition 0.000 title claims abstract description 19
- 239000004065 semiconductor Substances 0.000 title abstract description 3
- 230000000694 effects Effects 0.000 claims description 10
- 239000004744 fabric Substances 0.000 claims description 10
- 230000000295 complement effect Effects 0.000 claims description 2
- 230000001681 protective effect Effects 0.000 claims description 2
- 238000007789 sealing Methods 0.000 abstract 1
- 239000000463 material Substances 0.000 description 4
- 239000000428 dust Substances 0.000 description 3
- 239000002184 metal Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 229920002799 BoPET Polymers 0.000 description 1
- 239000005041 Mylar™ Substances 0.000 description 1
- 239000003082 abrasive agent Substances 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 239000005340 laminated glass Substances 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B37/00—Lapping machines or devices; Accessories
- B24B37/27—Work carriers
- B24B37/30—Work carriers for single side lapping of plane surfaces
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B41/00—Component parts such as frames, beds, carriages, headstocks
- B24B41/06—Work supports, e.g. adjustable steadies
- B24B41/068—Table-like supports for panels, sheets or the like
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
Abstract
Description
La présente invention a pour objet un portoir pour plaquettes minces, fragiles et déformables,dans une machine à polir. The present invention relates to a rack for thin, fragile and deformable wafers in a polishing machine.
Comme on le sait,une plaquette mince, fragile et déformable,notamment une plaquette d'un matériau semi-conducteur monocristallin,est maintenue, lors du polissage de l'une de ses faces dans une machine à polir,à l'aide d'un support ou portoir fixé à la tête de polissage de la machine.Un tel portoir est généralement cylindrique,dônt la face côté plaquette est agencée de maniére à pouvoir y appliquer une face de cette dernière par l'effet de vide ou de tension de surface. As is known, a thin, fragile and deformable wafer, in particular a wafer of a monocrystalline semiconductor material, is maintained, during the polishing of one of its faces in a polishing machine, using a support or rack fixed to the polishing head of the machine. Such a rack is generally cylindrical, so the face on the wafer side is arranged so as to be able to apply a face of the latter by the effect of vacuum or surface tension .
Dans le premier cas, le portoir,généralement en matière plastique,est muni de perforations de faible diamètre, ne dépassant 1,5 mm,permettant de relier sa face munie de rainures circulaires concentriques ou en forme de spirale,à laquelle doit être appliquée la face de la plaquette,à une enceinte à vide.On applique donc la plaquette contre cette face du portoir où elle est maintenue par l'effet du vide.Pour enlever la plaquette polie du portoir,on coupe le vide et on souffle par lesdites perforations,
Dans le cas où l'on utilise l'effet de tension de surfa ce,la face d'un portoir métallique,par exemple en acier inoxidable,est une face présentant une surface bien rodée ou une face revêtue d'un tissu poreux.Dans le premier cas,on applique la plaquette contre la face rodée sur laquelle elle adhère grace à l'effet de tension de surface.Dans le cas de la face revêtue d'un tissu poreux, on y applique la plaquette en exerçant sur elle une pression nécessaire à éliminer l'air entre le tissu et la plaquette qui adhère au tissu grace aux microporosités de celui-ci.Pour enlever la plaquette polie, on utilise généralement un filet d'eau ou d'air que l'on fait tomber sur sa tranche légèrement déformable.In the first case, the rack, generally made of plastic, is provided with small diameter perforations, not exceeding 1.5 mm, making it possible to connect its face provided with concentric or spiral-shaped circular grooves, to which the face of the wafer, to a vacuum enclosure. We therefore apply the wafer against this face of the rack where it is held by the effect of the vacuum. To remove the polished wafer from the rack, the vacuum is cut and blown by said perforations ,
In the case where the surface tension effect is used, the face of a metal rack, for example made of stainless steel, is a face having a well lapped surface or a face coated with a porous fabric. the first case, we apply the plate against the lapped side on which it adheres thanks to the surface tension effect. In the case of the side coated with a porous fabric, we apply the plate by exerting pressure on it necessary to eliminate the air between the fabric and the wafer which adheres to the fabric thanks to the microporosities of it. To remove the polished wafer, we generally use a trickle of water or air which we drop on its slightly deformable edge.
Les portoirs connus,décrits ci-dessus,présentent certains inconvénients qui portent préjudice à leur utilisation. The known racks, described above, have certain drawbacks which affect their use.
Ainsi,un portoir à vide présente l'inconvénient de devoir fréquemment être nettoyé ou changé à cause de colmatage ra pide de ses perforations par des poussières qui proviennent du polissage de la plaquette par des abrasifs en solution et qui sont aspirées par le vide.En effet, il n'est pas possible d'augmenter le diamètre des perforations1 pour empêcher leur colmatage, car la plaquette1 lors du polisagge,ne serait pas suffisamment appuyée en regard des perforations, ce qui provoquerait des marques sur sa face à polir.Un portoir à tension de surface ne se prête pas à l'automation
La présente invention a pour but d'obvier aux inconvénients précités en proposant un portoir utilisant aussi bien l'effet de vide,donc#des perforations,que l'effet de tension de surface,mais dans lequel les perforations sont protégées des poussières que provoque le polissage et qui se prête à l'automation.Thus, a vacuum rack has the drawback of frequently having to be cleaned or changed due to rapid clogging of its perforations by dust which originates from the polishing of the wafer by abrasives in solution and which are sucked up by the vacuum. Indeed, it is not possible to increase the diameter of the perforations1 to prevent their clogging, because the wafer1 during polishing, would not be sufficiently pressed opposite the perforations, which would cause marks on its face to be polished. at surface tension does not lend itself to automation
The object of the present invention is to obviate the aforementioned drawbacks by proposing a rack using both the vacuum effect, therefore # of the perforations, and the surface tension effect, but in which the perforations are protected from the dust that causes polishing and which lends itself to automation.
A cet effet, le portoir selon la présente invention est caractérisé en ce qu'il comprend un support cylindrique muni d'au moins une perforation axiale destinée à être reliée à une enceinte à vide, une de ses extrémités étant agencée de manière à pouvoir être fixée à la tête de polissage de la machine et l'autre de manière à pouvoir y appliquer de façon étanche et amovible une des faces d'un disque de faible épaisseur,dont l'autre face est agencée de manière à pouvoir maintenir une plaquette par l'effet de tension de surface ou par adhésion. To this end, the rack according to the present invention is characterized in that it comprises a cylindrical support provided with at least one axial perforation intended to be connected to a vacuum enclosure, one of its ends being arranged so that it can be fixed to the polishing head of the machine and the other so as to be able to apply therein in a sealed and removable manner one of the faces of a thin disc, the other face of which is arranged so as to be able to hold a plate by the effect of surface tension or adhesion.
Les caractéristiques et les avantages du portoir selon la présente invention ressortiront plus clairement de la description qui suit,dans laquelle on décrit deux variantes du portoir en se référant aux dessins annexes, donnés à titre d'exemple, dans lesquels:
La Fig.l est une coupe axiale du portoir selon une première variante.The characteristics and advantages of the rack according to the present invention will emerge more clearly from the description which follows, in which two variants of the rack are described with reference to the accompanying drawings, given by way of example, in which:
Fig.l is an axial section of the rack according to a first variant.
La Fig.2 est une coupe axiale du portoir selon une deuxième variante, fixé à la tête de polissage d'une machine à polir. Fig.2 is an axial section of the rack according to a second variant, fixed to the polishing head of a polishing machine.
et portant une plaquette à polir.and carrying a polishing pad.
Comme on le voit à la Fig.l,le portoir comprend un support cylindrique 1 muni d'une perforation axiale 2 dont les parties suppérieures 2a et 2b sont élargies pour permettre d'y introduire des moyens de fixation du support à la tête de polissage d'une machine à polir, comme cela sera expliqué lors de la description de la Fig.2.L'extrémité inférieure du support 1 comprend un évidement circulaire central 3 au fond duquel est encastré un joint étanche 4 concentrique à la perforation 2.Dans l'évidement 3 est introduite une partie 5a,de forme complémentaire,que comprend la face supérieure 5 d'un disque 6 dont la face inférieure est revêtue d'un tissu poreux 7 entouré d'une bague 8 applatie,en matière connue dans le commerce sous le nom de "Mylar",ayant une épaisseur supérieure à celle du tissu.Le rôle du joint 4 est d'assurer l'étanchéité entre les deux parties de la face Sa qu'il sépare.Le rôle de la bague 8 est d'empêcher les produits de polissage de pénétrer entre le tissu 7 et la plaquette à po- lir,lorsque celle-ci est appliquée sur le tissu,et de provoquer le décollage de la plaquette(érosion hydraulique). As seen in Fig.l, the rack comprises a cylindrical support 1 provided with an axial perforation 2, the upper parts 2a and 2b are widened to allow the introduction of means for fixing the support to the polishing head of a polishing machine, as will be explained during the description of Fig.2.The lower end of the support 1 comprises a central circular recess 3 at the bottom of which is embedded a tight seal 4 concentric to the perforation 2.In the recess 3 is introduced a part 5a, of complementary shape, which comprises the upper face 5 of a disc 6, the lower face of which is coated with a porous fabric 7 surrounded by a flattened ring 8, of material known in the art. trade under the name of "Mylar", having a thickness greater than that of the fabric. The role of the seal 4 is to ensure the seal between the two parts of the face Sa which it separates. The role of the ring 8 is to prevent the polishes from entering between the fabric 7 and the plate ette to polish, when it is applied to the fabric, and to cause the pad to take off (hydraulic erosion).
Le fonctionnement du portoir décrit ci-dessus et son utilisation dans une machine à polir seront décrits en se référant à la Fig.2 qui montre une deuxième variante du portoir fixé à la tête de polissage d'une machine à polir et portant une plaquette à polir. The functioning of the rack described above and its use in a polishing machine will be described with reference to Fig.2 which shows a second variant of the rack fixed to the polishing head of a polishing machine and carrying a plate polish.
Le portoir représenté à la Fig.2 diffère de celui de la
Fig.l uniquement par la face du disque 6 destinée à maintenir la plaquette.En effet, le disque 6,qui est en l'occurrence en acier inoxidable,présente cette face sous forme d'une surface rodée 9,de sorte que la plaquette lO,à polir est appliquée et maintenue par l'effet de tension de surface.The rack shown in Fig. 2 differs from that of the
Fig.l only by the face of the disc 6 intended to hold the wafer. Indeed, the disc 6, which in this case is made of stainless steel, has this face in the form of a lapped surface 9, so that the wafer 10, to be polished is applied and maintained by the surface tension effect.
Le support 1 est fixé à la tête de polissage 11 d'une machine à polir, non représentée,par l'intermédiaire d'un axe creux 12 solidaire de la tête ll,qui est introduit dans les perforations 2a et 2b dans la partie supérieure du support 1 et fixé à ce dernier par une fixation à baionnette.Une pièce 14,en forme d'une calotte sphèrîque,percée d'un trou central 15 et s'appuyant contre la paroi en forme de V que présente l'évasement qui relie les perforations 2 et 2a assure l'étanchéité entre l'axe 12 et le support 1 et relie# de manière étanche,par le trou 15,la perforation 2 au creux 12a de l'axe 12,relié lui-même à une enceinte à vide,non représentée.Il va sans dire que le support 1 peut être fixé à la tête 11 par d'autres moyens que ceux décrits et représentés à la Fig.2,l'essentiel étant que la perforation 2 et par conséquent la face 3 du support soit reliée à une enceinte à vide. The support 1 is fixed to the polishing head 11 of a polishing machine, not shown, by means of a hollow axis 12 integral with the head ll, which is introduced into the perforations 2a and 2b in the upper part of the support 1 and fixed to the latter by a bayonet attachment. A part 14, in the form of a spherical cap, pierced with a central hole 15 and pressing against the V-shaped wall which has the flare which connects the perforations 2 and 2a seals between the axis 12 and the support 1 and connects # in a leaktight manner, through the hole 15, the perforation 2 to the hollow 12a of the axis 12, itself connected to an enclosure empty, not shown. It goes without saying that the support 1 can be fixed to the head 11 by other means than those described and shown in Fig. 2, the main thing being that the perforation 2 and consequently the face 3 of the support is connected to a vacuum enclosure.
Comme on le voit à la Fig.2,la bague de protection 8 est remplacée par une collerette 9a laissée autour de la face 9 lors du rodage de sa surface. Il convient aussi de remarquer que le joint 4 pourrait être supprimé lorsque le fond de l'évidement 3 du support et la face du disque à appliquer sur ce fond présentent chacun une surface rodée. As seen in Fig.2, the protective ring 8 is replaced by a flange 9a left around the face 9 during the running-in of its surface. It should also be noted that the seal 4 could be eliminated when the bottom of the recess 3 of the support and the face of the disc to be applied to this bottom each have a lapped surface.
Les portoirs décrits ci-dessus fonctionnent de la manière suivante:
Après avoir fixé le support 1 à la tête de polissage d'une machine à polir,on met en communication la perforation 2 avec l'enceinte à vide associée à la machine,on introduit la partie Sa du disque 6 dans l'évidement 3 du support 1 et on l'applique contre le joint étanche 4 où il sera maintenu par l'effet de vide.Pour séparer le disque du support, il suffit de couper le vide et de l'éloigner soit manuellement soit automatiquement en soufflant sur sa face par la perforation 2.The racks described above operate as follows:
After having fixed the support 1 to the polishing head of a polishing machine, the perforation 2 is placed in communication with the vacuum enclosure associated with the machine, the part Sa of the disc 6 is introduced into the recess 3 of the support 1 and it is applied against the waterproof seal 4 where it will be maintained by the vacuum effect. To separate the disc from the support, it is enough to cut the vacuum and move it away either manually or automatically by blowing on its face through the hole 2.
Le disque 6 qui constitue en quelque sorte un mini-portoir est donc amovible.La plaquette 10 à polir peut être appliquée à sa face inférieure 7,respectivement 9,soit avant soit après son assemblage avec le support l.Grâce à l'amovibilité et à l'encombrement réduit de ce mini-portoir que constitue le disque 6,le portoir selon la présente invention permet un chargement et un déchargement rapide de plaquettes et cela automatiquement du fait que le mini-portoir permet le transport et la manutention automatique des plaquettes tout en les protégeant de chocs ou autres contraintes.D'autre part, la perforation 2 ne risque pas d'être colmatée par les poussières que provoque le polissage de la plaquette. The disc 6 which constitutes a sort of mini-rack is therefore removable. The plate 10 to be polished can be applied to its underside 7, respectively 9, either before or after its assembly with the support 1. Thanks to the removable nature and with the reduced overall dimensions of this mini-rack which constitutes the disc 6, the rack according to the present invention allows a rapid loading and unloading of wafers and this automatically because the mini-rack allows the automatic transport and handling of wafers while protecting them from shocks or other constraints. On the other hand, the perforation 2 is not likely to be clogged by the dust caused by the polishing of the wafer.
Il est évident qu'au lieu d'une seule perforation 2 le support 1 peut comprendre plusieurs perforations dont le nombre et le diamètre dépendront des dimensions du portoir, c'est-à-dire du diamètre de la plaquette à polir que le portoir doit maintenir. It is obvious that, instead of a single perforation 2, the support 1 can comprise several perforations, the number and the diameter of which depend on the dimensions of the rack, that is to say on the diameter of the polishing pad which the rack has to maintain.
En ce qui concerne le disque 6 du portoir représenté à la Fig.l,il peut être en métal ou en tout autre matériau indéformable à la chaleur et à la pression,tel que,par exemple, le verre stratifié.La bague de protection 8,en l'occurrence en "Slylar",peut être en tout autre matériau convenable. As regards the disc 6 of the rack shown in FIG. 1, it can be made of metal or any other material which cannot be deformed by heat and pressure, such as, for example, laminated glass. , in this case in "Slylar", can be in any other suitable material.
Claims (6)
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR8110182A FR2505713A1 (en) | 1981-05-18 | 1981-05-18 | Semiconductor wafer carrying head for polishing machine - has circular disc covered in thin tissue with reduced pressure behind tissue to hold wafers |
JP57084680A JPS57201169A (en) | 1981-05-18 | 1982-05-18 | Holder for extremely thin fragile deformable wafer used in grinder |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR8110182A FR2505713A1 (en) | 1981-05-18 | 1981-05-18 | Semiconductor wafer carrying head for polishing machine - has circular disc covered in thin tissue with reduced pressure behind tissue to hold wafers |
Publications (2)
Publication Number | Publication Date |
---|---|
FR2505713A1 true FR2505713A1 (en) | 1982-11-19 |
FR2505713B1 FR2505713B1 (en) | 1985-01-11 |
Family
ID=9258756
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
FR8110182A Granted FR2505713A1 (en) | 1981-05-18 | 1981-05-18 | Semiconductor wafer carrying head for polishing machine - has circular disc covered in thin tissue with reduced pressure behind tissue to hold wafers |
Country Status (2)
Country | Link |
---|---|
JP (1) | JPS57201169A (en) |
FR (1) | FR2505713A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4947598A (en) * | 1982-04-23 | 1990-08-14 | Disco Abrasive Systems, Ltd. | Method for grinding the surface of a semiconductor wafer |
US5122481A (en) * | 1990-09-05 | 1992-06-16 | Sumitomo Electric Industries, Ltd. | Semiconductor element manufacturing process using sequential grinding and chemical etching steps |
EP0805000A1 (en) * | 1996-05-02 | 1997-11-05 | MEMC Electronic Materials, Inc. | Semiconductor wafer post-polish clean and dry method and apparatus |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5997856U (en) * | 1982-12-18 | 1984-07-03 | 豊田工機株式会社 | wrap device |
JPS63124460U (en) * | 1987-02-07 | 1988-08-12 | ||
JP2007053949A (en) * | 2005-08-24 | 2007-03-08 | Shimano Inc | Landing net handle and its plug |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3977130A (en) * | 1975-05-12 | 1976-08-31 | Semimetals, Inc. | Removal-compensating polishing apparatus |
US4194324A (en) * | 1978-01-16 | 1980-03-25 | Siltec Corporation | Semiconductor wafer polishing machine and wafer carrier therefor |
-
1981
- 1981-05-18 FR FR8110182A patent/FR2505713A1/en active Granted
-
1982
- 1982-05-18 JP JP57084680A patent/JPS57201169A/en active Pending
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3977130A (en) * | 1975-05-12 | 1976-08-31 | Semimetals, Inc. | Removal-compensating polishing apparatus |
US4194324A (en) * | 1978-01-16 | 1980-03-25 | Siltec Corporation | Semiconductor wafer polishing machine and wafer carrier therefor |
Non-Patent Citations (1)
Title |
---|
IBM TECHNICAL DISCLOSURE BULLETIN, vol. 22, no. 6, novembre 1979, pages 2303,2304, New York (USA); * |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4947598A (en) * | 1982-04-23 | 1990-08-14 | Disco Abrasive Systems, Ltd. | Method for grinding the surface of a semiconductor wafer |
US5122481A (en) * | 1990-09-05 | 1992-06-16 | Sumitomo Electric Industries, Ltd. | Semiconductor element manufacturing process using sequential grinding and chemical etching steps |
EP0805000A1 (en) * | 1996-05-02 | 1997-11-05 | MEMC Electronic Materials, Inc. | Semiconductor wafer post-polish clean and dry method and apparatus |
Also Published As
Publication number | Publication date |
---|---|
FR2505713B1 (en) | 1985-01-11 |
JPS57201169A (en) | 1982-12-09 |
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