真空镀膜设备拥有一个包含至少一个阴极真空室系统.docx

4114,261，80845 Apr. 14, 1981Unted States Patent 19Walter51 Int.Cl3. C23C 15/00; C23C 13/1052 U.S.118/324 ;204/298 ;84162611833371236900241519242.43054 VACUUM COATING APPARATUS WITHCONTINUOUS OR INTERMIHENTTRANSPORT MEANS75 Inventor:Heinz Walter, Hanau, Fed. Rep. ofGermany73 Assignee:Leybold-Heraeus GmbH, Cologne,Fed. Rep. of Germanypi Appl. No.: 971,2752 Filed:Dec.0,197830】 Foreign Application Priority DataOct 12, 1978 DE Fed. Rep. of Germany 2844491118/733 ;118/729 118/725 118/719 ;118/50358 Field of Sewch118/49.1，50.1，48,118/49, 324, 503, 719, 729, 725, 733, 715;204/29856References CitedU.S. PATENT DOCUMENTS3,132,9665/1964Hughes etal.18/3243；288；70011/1966Needham et al.204/2983:596:2857/1971Gottwald118/3243；873；0253/1975Quarnstrom118/3243；931；7891/1976Kakei et aL .118/503.4,062)31912/1977Roth al.204/298412/1978 533131 Bialkoetal.204/2984,149.92312/1978 Uehara et 204/298 _FOREIGN PATENT DOCUMENTS7/1949 Fed. Rep. of Germany.7/1965 Fed. Rep. of Germany.5/1969 Fed. Rep. of Germany.3/1974 Fed. Rep. of Germany.2/1976 Fed. Rep. of Germany .OTHER PUBLICATIONSByrne，T. M. et al., IBM Tech. Disci. Bulletin，pp.1034-1036, vol. 13, No. 4, 10/1970.Primary ExaminerCktks l Bowers, Jr.Attorney, Agent, rf/wsprung, Felfe, Horn, Lynch& Kramer57ABSTRACTVacuum coating apparatus having a vacuum chambercontaining at least one cathode system and having asystem for the continuous or intermittent transport ofsubstrates during the coating. The transport systemincludes flexible，endless conveyor means in pairsguided in the manner of two parallel chain drives overwheel pairs positioned at a distance from one another inthe formation of two straight runs. The substrates arefastened to the conveyors so as to be movable parallel tothe cathode system. The straight runs of each endlessconveyor is guided vertically at least in the area of thecathode systems. Qaims, 7 Drawing FiguresU.S. Patent Apr. 14,1981Sheet 3 of 64,261，808FIG.FIG.38893 1861VI .idv ludvad s.nU)U.S. Patent Apr. 14, 1981Sheet 5 of 74,261,808FIG.610U.S. Patent Apr. 14, 1981 Sheet 6 of 64,261，808544,261，8085101520253035404550556065VACUUM COATING APPARATUS WITHCOINUOUS OR TRANSPORTMEANSBACKGROUNDThis invention relates to a vacuum coating apparatushaving a vacuum chamber, having at least olie cathodesystei，and having a system for the continuous trans-port of the substrates during the coating process, includ-ng endless transport meais disposed air-wise，whichar guided in the manner of tWo parallel chain drivesover sets of two wheels set apart from one another，thereby forming two straight runs, and to which thesubstrates can be fastened，thus enabling the substratesto be moved parallel to the cathode system.In vacuum coating apparatus which are designed fora high throughput，the bain problem lies in i preciseand trouble-free transport of the largest possible num：ber of substrates per unit of time through the actualcoating zone or，in some cases，through a plurality ofcoating zones, and in some cases through still otherpretreitment and after-treatment zones. It can be asSumed that such treatment zones contained within arelatively larger vacuum chamber are separatedone another either by their principle of operation, and-/or by special shielding, partition walls, etc. Examplesof treatment stations ire cathode sputteringcathodic etching systems or glow discharge systems,preheating and afterheating stations, etc. In large indus-triaHnstaSations，the contnuous or intermittent trans-port of substrates cails for appropriate mechanical con-struction measures, which inevitably produce at leastsome detritus，and inevitably，too, sonie of the coatingmaterial condenses upon he interna】 parts of the apparatus，and after a time it begins to flake off，resulting inthe danger of contamination of the substrates.When vacuum chambers are divided for the purposeof different process steps，it is customary to sepaTatG thecompartments by meaiis of flap valves. This necessitatesseparate transport systems fr each chamber and com-plGx electrical control and synchronization.It is also possible to pass the substrates including theirtransport means through a number of chibers, inwhich case the partition walis contain slots for the pas-sage f the substrates，and these slots are filled ascompletely as possible by the substrate frames so as toprevent contamination. The passage of the substratethrough the partition walls，howGver，requires highprecision in the transport means. In additiOn，for thepose of atteining short pump-down time，the volumeOf the chamber mUst be rGduced to a minimum. Theserequirements are in some ways diametricaUy opposed，at ieast in large industrial plants，so that continuOUsly orintermittent operating acuum coating instaiahave hitherto nt been widely used in practice.German DDS No. 2,415，19 has disGlosed a coatingsystem of the general class described above, whichconsists substantially of a single，hollow-cylindricalcathode system，i,e” anode and Cathode are constructedas portions of the periphery of a hollow cylinder sur-rounding the sputtering zone and provided with a plu-rality of longitudinal slits. The Substrates are trns-ported by means of a horizontal chain conveyorthrough a segment at the bottom of tpe horizontal，holloW-cylindrical cathode system，preferably in thehorizontal position so that they can te coated on oneside only. This means，of course，that the substrates canalso run vertically to reduce the danger of contamina-tion, but in this case evidently all that is thought of issubstrates in a vertical position on the horizontal trans-port system. For stacking chambers containing sub-Strate magazines or vacuum locks are to be situated atboth ends of the sputtering chamber. However，thedanger of contamination cannot be reduced in the de-scribed manner to the desirable degree. Contaminationapparently was not very important in this known appa-ratus, since the embodiment presented is a laboratorysystem whose vacuum chamber is composed to an im-portant degree of a glass receptacle. In the applicationof this principle of construction to a large industrialinstallation，the amount of space required in the hori-zontal direction is great，the cathodes are poorly acces-sible, and the sealing of the gaps in the individual parti-tions of the vacuum chamber is very unsatisfactoryunless the transport system is horizontally guided withgreat precision.But even in the evaporation type depositing systemsfrequently cited for purposes of Comparison, the hori-zontal direction of transport has been used wheneverflexible continuous conveyor means are used:Thus it is known from German Pat. No. 1，183,337 tosuspend pJate-like substrates from a horizontal orslightly inclined frame and to carry them in the verticalposition successively through a vacuum evaporationZone by means of a horizontal transport chain. As aresult，very irregular coating density distributions areproduced, since the vapor particles strike the substratesurface at different angles in each position of the sub-strates and with respect to each unit of the surface of thesubstrate.German Pat. No. 1,236,9如 has furthermore discloseda vacuum evaporation apparatus having a conveyorchain circulating substantially in the horizontal direc-tion. In the area of the bottom run of the chain，a plurality of plate-like substrates are arrayed in close order ina vertical position and picked up by the transport chainat certain intervals. The upper run of the chain passesover a plurality of evaporating crucibles. In order toobtain a uniform distriliution of the coating thickness，the substrates，while being carried by the uper run ofthe chain，must be turned to a horizontal position by aspecial guiding means. Only in this manner it is possibletO vapr coat the substrates on one side only. The simul-taneGus vapor coating of the upper surface，for exampleby means Of special vapor guiding means, has provenimpractical degpite nunierous attempts. With regard tospice requirement and the difficulties involved if thevacuum Chamber is divided into smaller chambers，thesame disadvantages are encountered as in the methodpreviously described.It is also known to fasten substrates to cylindricaldrums whose axis s horizontal. Vapor deposition in thiscase，however，tafces place only on a sMall portion ofthe circumference of the drum，because the rest of itserves only as a magazine，and the height and breadth ofa drum have an unfavorable influence on the dimensionsand volume of the vacuum chamber. Such an apparatusis the subject matter of German Pat. No. 841，26Lastly，German DAS No. 2,420,430 also discloses theconstruction of cylindrical drums as holders。f Wade-shaped substrates. The drum，however，serves only as amagazine for the blades which are aligned radially withthe drum axis，and for their transport For the purposeof coating by vacuum deposition，the blades are individ-ually shifted from the drum into coating chambersvhiie they are in a substantially horizontal position. Thevapor deposition apparatus involved is extraordinarilycomplex in construction and in operation; in addition，itrequires a considerable amount space due to the largedrum diameter.5101520253035404550556065SUMMARYThe Invention provides a vacuum coating apparatusof the kind described in the beginning，i.e.，one havingat least one cathode system，in which simultaneouscoating on both sides will be possible，without the dan-ger that the substrates and/or the cathodes might be-come contaminated.This is accomplished in accordance with the inven-tion，in the vacuum coating apparatus described in thebeginning, in that the straight sections of each endlessconveyor means are vertical at least in the area of thecathode system.It is，of course，especially desirable for the straightportions of the endless conveyor means to be vertical ontheir entire length，and this can be accomplished mostsimply by disposing the pairs of wheels over which theendless convGyor means is guided such that one will bevertically above the other. It is to be noted，however，that a deviation from the exclusively vertical guidanceof the transport means can be desirable if，for example，the cathode system is to be combined with a vacuumevaporation system.DESCRIPTIONThe subject of the invention is a complete departurefrom the design principles of the prior aft，and iS distin-guished by the following advantages: The principaldimensions of the vacuum chamber are substantiallyvertical，so that only a small amount of floor space isrequired for the apparatus. The sputtering surfaces ofthe cathode system or systems，i.e7, the taget surfaces,are vertical，as are the surfaces of the substtes，at leastduring the sputtering process. In this manner，no impu-rities，such as might be produced from the cathodes，Canfall on the substrates or vice versa. If the cathode system is a two-sided system, it is easily possible to cOatboth sides of the substrates simultaneously. The term“substrates，” as used herein，is to be understood to applynot only to single substrates of large surface area，foutalso to multiple arrays of substrates fastened to substrateframes. Two-sided coating includes cases in which sub-strates are arranged in pairs back to back，so that eachindividual substrate is coated on one side only，but thetwo substrates are coated together on their outwardlyfacing surfaces. Examples of substrates are lenses，mir-rors，electrical contacts, wafers，etcIf the dimensions of the apparatus of the invention aresmall，i.e，if the pump-down time is short，the apparatuswill have a hig capacity of production The hexibleendless conveyor means，which consist preferably ofendless chains carried around appropriate sprockets，aresimple and reliable in design; even if the substrates arecomparatively heavy，they require no additional guid-ance or support，so that even ii the vacuum chamber isdivided there is no difficulty involved with regard tothe sealing of the slits in the partitions adjaCnt theendless conveyor means. The vaCuum chamber can thusbe equipped with a plurality of preferably variable sta-tions for the treatment of the substrates. For exampie，high-frequency cathodes, direct-current cathodes，etch-ing cathodes or heating means can be provided in anydesired sequence.It is especially advantagous to make the horizontaldistance etween the endless conveyor means，or be-tween the wheels of each set，greater than the horizon-tal width of the cathode system. This effectively pre.vents the endless transport means from being c.atedtogether with the substiates.rr the pulpose of increasing production capacity，the apparatus Of the invention CaA be advantageouslydeveloped by providing at the bottom end of the vac-uum chamber，in the vicinity of the bottom wheels，afeed chamber containing at least one substrate maga-zine，and with a means for attaching them and a meansfor detaching them from the conveyor means The at-taching and detaching means means can in a very simplemanner consist of push rods which are the prolongationof hydraulic or pneumatic actuators. If these hydraulicor pneumatic actuators operate in the vertical direction，the substrates can be hooked onto the endless conveyormeans and unhooked therefrom in an especially simpleand reliable manner，since this procedure is perforniedin substantially the same direction in which the sub-strates are moving. In an arrangement of this kind，sepa-rate magazines can be used for the uncoated substratesand the coated substrates，within a common lock cham-ber serving for both the insertion and the removal of themagazines. Thus sufficient time is allowed for preheat-ing and outgassing.Lastly，by a vertical arrangement of the transportsystems, an especially simple and advantageous designof the vacuum chamber can be achieved by making thevacuum chamber to consist of a frame having two doorsdisposed one on each side of the frame and substantiallymatching the frame profile，while some of the functionalmeans such as cathodes，heating stations，etc.，aremounted on the doors. These functional means are thuseasily accessible when the doors are openedan advantage which is not to be underestimated in view of theneed for the replacement of the sputtering target.Embodiments and their manner of operation andadditional advantages will be described hereinafter withreference to FIGS: 1 to 7 wherein:FIG. 1 is a vertical cross section through a vacuumcoating apparatus providing a side view of the wheelsand the straight sections of a flexible endless conveyormeans，FIG. 2 is a vertical cross section through the subjectof FIG. 1 at a right angle thereto, i.e.，providing a frontview of the target surfaces of two cathode systems andof the substrate surfaces which are to be coated.3 1 is a top plan view of the subject of FIGS. 1and 2 with doors closed (solid Jines) and doors open(broken lines).FIGS. 4 and 5 are partial views of the interior of theapparatus to explain the interaction of the substrateswith the flexible endless conveyor means.FIG. 6 shows the lower end of the vacuum chamberof FIGS. 1 and 2, with an attachment in the form of aloading chamber containing two substrate magazines，andFIG. 7 is a variant of the subject of FIG. 1 in a similarrepresentation，but with the addition of a vacuum vapordeposition system.In FIG. 1 there is represented a vacuum chamber 10which consists of a fralne 11 and two doors 2 and 13whose profile corresponds substantially to the frameoutline To both doors are fastened the means essentialto the coating process，that is，on door 12, the outer partlia of a cathodic etching system 14, a heating system15, and the outer part Of a cath.de sputtering sys-tem 16. On the opte door 13 are fastened theparts 17 and 1 Of cathode sputtering systems 17 and18, and heating mes 19 and 20. The doors 12 and 13are reinforced by ribs 21 against the atmosphericsure.The corresponding internal parts I, 16b, lib and18 of the cathde Systems 14, 16，17 and 18 are alsofastened to the frame 11 in a manner not shown, as arealso the reflectors d radiation shields 2223heating means 15, 19 and 20.The vacuum chamber 10 is divided by a partition 24into an upper chamber 25 and a Jower charaber 2. Inthe uppei chamber 25, there is fastened at the highestpossfeie point to the vertical frameShaft 27 With a pair of wheels of which only the frontwheel 28 is visile in FIG. 1，while in FIG 2 the rearwheel 29 is also representedIfllike manner，there is journaled in the lower cham-ber 26 a shaft 30 on whiCh there is fastened a pair ofwheels of which only the front wheel is visible inFIG. h while in FIG. 2 the rear wheel 32 is also to beseen. The suction connection 34 leading to a pump set33 leads into the lower chamber 26, while a gas line 36for the production of a suable sputtering leads through a gas valve 35 into the upper chamber 25.A flexible endless conveyor means 37 and 38 is passedaround each pair of wheels 28-31 and 29-32,tively，and it Gan best consist of