METHOD AND INSTALLATION FOR THE APPLYING OF A COATING ON A SUBSTRATE OR TAPE

Abstract: Improved installation (10), whereby in a first section (22) coating (24) is applied on substrate (14), moving through a passage (16) under double floating condition, in a following section (26) a layer fluid (28) is applied on said layer coating (24) and in the following sections (30) and (32) the removal takes place of said fluid layer with thereafter a drying of the remaining coating layer.

Description: tape, . The invention relates to a method and installation for applying a coating on a flat surface. Such method and installation are described in the Dutch Patent Application no, 82 00 753 of the applicant. 5 In this neω Application some improvements are disclosed. For instance, in the coating supply station the supply of a precise¬ ly measured volume of coating per second takes place towards a narrow gap in between the substrate and a very smooth applicator segment. Thereby the flow restriction of the gap section in the direction, 10 which is opposite to the direction of substrate displacement, is that large, that no coating can leak away in this direction. In the next section the coating layer, applied on the substrate, is supplemented with an additional layer of thinner or other evaporizable liquid. 15 Next, in another section a gradual removal of this second layer ta¬ kes place, and whereby the coating layer cannot come into a mechanical con¬ tact with components of the installation. The other, non-processing side of the- substrata moves along a guide wall with a medium cushion in between and whereby the applied coating beco— 20 mes separated from a wall section of the following passage area, which over some distance is removed from the substrate, passing through. This contact-free displacement is maintained untill the coating in the following section is dried and whetheror not hardened. Further details follow from the description of the following Figures: 5 Figure 1 is a section of a process installation, in which a coating is applied on a substrate, passing through, and whereby thereafter the coa¬ ting is dried. Figure 2 is an enlarged section of the installation for applying a coating according to Figure 1. ' 0 Figure 3 is the first section of the installation according to Figure 2. Figure 4 is the second section of the installation according to Figu— re 2. Figure 5 discloses in detail the section for applying the coating. 5 Figure 6 discloses -in detail the section for applying the thinner. Figures 7, 8 and 9 show in detail the removal of the thinner and the thickening of the applied coating layer. WIPO Figure 10 is a cross section of an installation for applying a coa¬ ting at trje passage area. Figure 11 is a crass section of the housing of the coating applica¬ tor. In Figure 1 the installation 10 is shown. Thereby in a preceding section 12 a drying of the substrate 14 in the narrow passage 16 has taken place by means of warm gaseous medium, such as nitrogen, which is supplied through channels 18 and discharged through channels 20, see also Figure 2. In section 22 the applying of coating 24 on the substrate 14 takes place, and in section 26 the applying of thinner 28. In section 30 the removal of this thinner 28 and thickening of the applied coating layer occurs, whereas in module 32, which for instance can be a micro-wave oven, a drying and hardening of the coating, applied on the substrate, takes place. In the next section 34 a second coating layer is applied on the sub¬ strate 14, with in module 36 a repeated drying and hardening of this second coating layer. In Figure 2 the section 22 for applying coating is ' enlarged shown at the passage 16. Through successive channels 18 supply of nitrogen takes pla— ce owards the processing side of the substrate 14 and through channels 40 the supply of nitrogen towards the non—processing side of this substrate. Thereby the extremely smooth and flat segment wall sections 42, 44 and 46 in combination with micro medium cushions 48 and 50 provide a good guidance for the substrate. Simultaneously with the nitrogen evaporated thinner can be supplied. Through discharge channels 20 the discharge of supplied medium oc¬ curs, whereby such a discharge can be connected with a high vacuum pump. The supply channels 18 are located in between the segments 56 and 58, which are positioned in the lower transporter section 60, whereas the chan— nels 40 are located in between the segments 62 and 64 of the upper trans¬ porter section 66. * The discharge channels are located in between the successive trans¬ porters. In section 22, see also Figures 3 and 4, coating is supplied through a great number of supply channels 68, positioned aside each other and such in precisely measured volumes per second. Thereby this coating fills the gap 70 in between segment 72 and the substrate 14. Thereby the velocity of the coating in this gap corresponds with that of the substrate. In gap 74 only a limited urging of coating takes place and so this gap, filled with coating, in combination with the displacement of the sub¬ strate, functions as a coating lock. 3 In that way by means of a coating supply of 100 mm per minute to¬ wards a 5" substrate (wafer), displacing at 4 mm per second, a distance in upward direction of approximately 3 micrometer is maintained in between such substrate and segment 72. Thereby the volume of coating is in relation with the thickness of the coating layer, which is wanted after hardening thereof. Furthermore, the flow restriction of gap 70 for the coating is that large, that such gap also functions as a coating lock, with no urging of superfluous coating towards channel 76. Only coating as part of this lock is carried away by the substrate over the ultra smooth, highly polished passage wall 73 of segment 72. Thereafter in section 26 through channel .76 thinner 28 is supplied towards the gap in between the substrate 14 and segment 80, and such in a precisely measured volume per second. This second layer prevents any deformation of the smooth surface of the applied coating layer and mixes with this layer only to a very limited extent. Thereby the medium cushions in the passage gaps above the substrate urge the substrate to rest upon the applied layers of coating and thinner. In section 30, see also Figure 4, the removal of thinner takes place through a great number of discharge channels 82, located aside each other. This discharge is also established by means of gaseous medium 84, which is supplied towards gap 88 through a great number of supply channels 86, posi¬ tioned aside each other. Thereby this medium, whirling in this gap towards discharge 82, carries away particles of thinner, see also Figure 7. These warm gases, also flowing through gap 90 towards the following discharge channel 92, already dries the applied coating layer 78 to a limi¬ ted extent. The combination of thinner, supplied through channels 94, and nitro¬ gen, which is supplied through channels 96 towards gap 98 on top of the sub— strate 14 near the coating supply, also serves for the removal of coating out of passage 16, if no substrate section is moving through. Thereby such a combination of medium is continuously discharged through the upper discharge channels 100 and the lower discharge channels 20, 82 and 1 02. In that way warm coating with a high percentage on solids (up to 70 %) can be applied on the substrate with a perfect planarisation of "stepped" surface topography of this substrate and an extremely fast processing. In Figure 10 the installation 10 is shown at the location of the coa¬ ting supply section 22. Thereby in the sidewall 104 of segment 72 the extre¬ mely narrow channels 68 are etched, the flow restriction thereof being large in co parance with the flow restriction of sections of passage 70, corres¬ ponding therewith. Through combination channel 106 the channels 68 are supplied with coa¬ ting from the coating supply 108. Consequently, through each passage section approximately the same quantity of coating per second is urged towards the passage, with approximately the same width of such passage sections. A change in width between the section automatically results in coπsi— derable changes in the thrust of the coating in this section, working on the substrate. These changes in forces by far exceed the differences in the combi¬ nation of other forces, working on the substrate and the internal tension forces of these substrates. As a result, the width of the gap 70 and consequently the thickness of the applied coating is completely uniπdependent of the following variations of the substrate conditions: 1. Tolerance in thickness; 2. Bow; 3. Variation in linear thickness (taper); and 4. Non—linear variations in thickness. In the upper part of the installation 10 in segment 110 a great num¬ ber of channels 92 are etched, through which thinner from supply 114 and through combination channel 112 is urged towards upper gap 90, to provide a cleaning of passage 16. In Figure 11 " the segment housing 116 is shown, with therein located both segments 72 and 118. Through the respective channels 106 and 120 the channels 68 and 76, positioned in segment ,72, are connected with the res¬ pective supplies 108 and 124. After the mounting of the segments in the housing the surface 126 is machined to an ultra smooth and flat surface with a roughness, which is smaller than 0,5 micrometer. Thereby during this machining cleaning liquid is urged through channels 68 and 76. OMH The shown installation enables the applying of coating with a layer thickness ^ less than 3 micrometer, and such together with extremely small and allowable differences in such thicknesses. OMPI

Claims: C L A I M S 1. Method for the applying of a coating on a substrate, moving through a passage of a cabin, consisting of: as seen in length direction of said cabin passage by means of suc- cessive- mouthes for supply and discharge of medium the maintaining of media cushions in between the main sidewalls of said passage and the flat sides of said substrate; through at least one mouth the supply of said coating to the proces¬ sing side of said substrate; and as seen in length direction of said cabin passage, by means of a measured supply of said coating per second in co-αperation with other media, acting on said substrate, in the passage sections in front of and behind said mouth for coating supply at least temporary the establishing of an at least partly with coating filled passage in between the coating applicator block and said substrata in such a way, that the speed of said coating is maximal not considerably larger than that of said substrate. 2. Method according to Claim 1 , wherein the structure of said cabin is such, that the speed of movement of said coating through said coating passage is not larger than the velocity of said substrate. 3. Installation, wherein the method according to one of foregoing Claims is incorporated, whereby said installation has a narrow passage for said substrates, on both sides of said passage in length direction thereof successive mouthes for supply and discharge of media in packages of seg¬ ments are located and in addition means are incorporated to enable the es— tablishing of the with coating filled passage section aside the substrate, passing through. 4. Installation according to Claim 3, wherein , as seen in length direction of said cabin passage, immediately in front αf said coating sup¬ ply channel such a first segment wall section is located, that together with said substrate, moving through said passage, a first coating passage is created, behind said coating supply channel a second segment wall sec¬ tion is located, said wall section being for at least part thereof at least almost parallel with said first segment wall section and furthermore the structure of said installation is such, that during the processing under influence αf media in said passage, acting on said substrate, in both coa¬ ting passages a coating lock is established and at least temporary maintained 5. Method of the installation according to Claim 4, whereby by regu¬ lating the volume of the supplied coating per second in combination with O PI both coating locks the wanted thickness of the coating layer, applied on said substrate, is obtained. 6. Method according to Claim 5, whereby thereafter in a following section the coating layer, applied on said substrate, is covered with a layer of evaporizable fluid medium. 7. Method according to Claim 6, whereby said medium is a thinner for said coating. 8. Method according to Claim 6, whereby said fluid is supplied in measured quantities per second through a supply mouth. 9. Method according to Claim 8, whereby the velocity of said fluid is not considerably larger than that of said substrates. 10. Method according to Claim 9, whereby said velocity of said fluid is not larger than that of said substrate. 11. Installation, wherein the method according to one of foregoing Claims is used, as seen in direction of movement of said substrate in front of said supply block for said coating supply a second supply block with a supply mouth is located for supply of said medium in fluid phase and whereby the passage -jail of said second supply block in front of said mouth over some distance is removed from the imaginary lengthening of said passage wall of said first supply block. 12. Installation according to Claim 11, wherein, as seen in direction of movement of said substrate said passage wall behind said second mouth is the segment wall section in front αf said coating supply. 13. Method according to Claim 10, whereby thereafter in a following section the applied layer fluid medium at least partly is removed. 14. Method according to Claim 13, whereby use is made of warm gaseous medium, which is fed through a passage section along said layer, applied on said substrate. 15. Installation, wherein the method according to Claim 14 is used and, as seen in direction of movement of said substrate, in front of the ap¬ plicator block for said fluid medium a third applicator block with a supply mouth for gaseous medium is positioned, in between both applicator blocks a discharge mouth for discharge of both gaseous and fluid medium is located and the passage wall area in between both mouthes are removed over some dis- tance from the imaginary lengthening of the passage wall in front of said second applicator block. 16. Installation according to Claim 15, whereby, as seen in direction of movement of said substrate, in front of said third applicator block a O PI fourth applicator block for supply αf gaseous medium is positioned and in between said block and said third applicator block a second discharge mouth for discharge of both gaseous, vaporized and fluid medium is located. 17. Installation according to Claim 15, whereby the applicator blocks farming passage wall sections at the main processing side of said substrate, are positioned such, that said sections by means of media cushions offer such a guidance for said substrate, that said coating layer, applied on said substrate, cannot rest against said applicator blocks, located at the processing side. 18. Installation according to Claim 17, whereby after one or more applicator blocks, in between successive supply blocks for gaseous medium to provide floating medium cushions for said substrate, at least one oven structure is positioned for drying and/or hardening αf said coating layer, applied on said substrate. 19. Installation according to Claim 18, whereby the distance between said successive supply blocks is that restricted, that at least the side- wall of said substrate, on which said coating is applied, remains free of mechanical contact with oven sections during the passing through thereof. 20. Installation according to Claim 18, whereby said oven is an in— fra—red or micro-wave oven. 21. Installation according to one αf foregoing Claims, whereby the structure is such, that through supply channels at the πoπ-prαcessiπg side αf the cabin passage at least in the passage area of the coating supply section also thinner in fluid phase is urged towards said cabin passage. 22. Method of the installation according to one of foregoing Claims, whereby use is made of a coating, having a high percentage on solids. 23. Method according to Claim 22, whereby said coating has a tempera¬ ture of at least 40 C. 24. Method according to Claim 23, whereby in at least the passage 'area of the coating supply also a high temperature is maintained. • 25. Method according to Claim 24, whereby during the moving of said substrates through said coating 'applicator section, said substrates also hav approximately the temperature of said coating. 26. Installation according to one αf foregoing Claims, whereby in a segment separate branched channels for supply of said coating are located aside each other, said channels on one end thereof are connected with a common supply channel, on the other end are connected with at least one mouth and each of said branched channels have the same flow restriction , CM-PI being sized in such a way, that said restriction is at least the same as the flow restriction of corresponding sections of said first coating pas- sage in front of said coating supply. 27. Tape, as a series of substrates connected with each other, whereby said tape is used in the method and installation according to one αf foregoing Claims. O PI

Inventors: BOK EDWARD, BOK, EDWARD
Applicants: BOK EDWARD, BOK, EDWARD
Application year: 1984
Main classification: B05C5
IPC codes: B05C5, B05D1