IMPROVED INSTALLATION FOR FLOATING TRANSPORT AND PROCESSING OF SUBSTRATES

Abstract: Improved process installation (10) for double floating transport and processing of substrates (30), consisting of successive transporters (18) with process slots (28) positioned in between and tape (80) as transporting means for said substrates (30) and whereby tensioning means (24), (96) and (104) prevent an unallowable deformation of the transporters (18) and tape (80) during the processing with accompanying heat development.

Description: Improved installation for floating transport and processing of substrates. The invention relates to process installations ωith a double., floating transport and processing of substrates. In the process installations during processing of such substrates heat is induced by the process medium into the substrates. Such takes place in particular ωith ion implantation, plasma etching, -plasma en¬ hanced applying of metal, plasma milling, oxidation systems etcetera. Furthermore, in stations as part of a floating transport track, in ωhich processing, such as cleaning and drying of the substrates, takes place. Thereby the transporters, used for such a preferably double floating transport of the substrates and located in betωeeπ successive process slots, function as heaters or coolers of the substrates. The double floating transport and processing systems for the sub¬ strates are described in for instance the Dutch Patent Applications No's 8 203 318, 8 300443 and 8 300 649 of the applicant. Differences in temperature in such transporters result in a conside¬ rable boωing of the passage ωall-sections of these transporters, uith the folloωing disadvantages: 1. a locally critical reduction of the passage width; ' and 2. a variable h'eat transfer of the substrates to such transporters. The installation according to the invention now is characterized in that such transporters are stretched in longitudinal direction. Thereby an effective use can be made of a series of hydraulic de¬ vices, ωhich urge the mounting frames, as used for a series of transpor¬ ters, from each other. If for the processing of the substrates use is made of a tape, to ωhich these substrates are temporary secured, and whereby processing of both substrates and tape takes place, then the tape can also be considered as a transporter for such substrates. Thereby such tape acts as an excellent means for heat transfer and consequently such tape is also pre-stressed to prevent a deformation thereof. Further positive features of the installation follow from the des¬ cription of the following Figures. . _ _ . Figure 1 is a top view of the installation according to the iπven- tion, ωith therein positioned a series of pre-stressed transporters. Figure 2 is a cross section of the installation according to Figure 1 at the transporter-arrangement. Figure 3 is a cross section of the installation according to Figure 1 at the hydraulic tensioning devices. Figure 4 is an enlarged cross-section of the transporters, as used in the installation according to Figure 1. Figure 5 is a side view of the mounting frame, on ωhich a series of transporters are secured and pre—stressed. -■- Figure 6 is a schematic of the transporter structure according to Figure 1 without stretching forces, applied thereon. Figure 7 is a schematic of the transporter structure according to Figure 6 with applied stretching forces thereon. Figures 8 and 9 show a process installation, in ωhich the combina¬ tion of substrates and tape are fed through a number of transporters and process slots. Figure 10 is an enlarged longitudinal cross-section of two trans¬ porters with in between a process slot. Figure 11 is an enlarged longitudinal cross—section of a modified module section with aπisαtropic plasma etching of substrates, passing through the process slot. « In Figure 1 the process installation 10 is shown. Thereby the trans¬ porters 18 are by means of the hollow bolts secured to the mounting fra- mes 12 and 14. In these mounting frames 12 and 14 the contact areas 22 for the hy¬ draulic teπsiαners 24 are located.. These tensioners urge with one end against such frame and ωith the other end against the blocks 26, which are positioned aside the transporters 18. In between successive transporters 18 successive process slots 28 are located, in ωhich processing takes place of the substrates 30, passing through. In Figure 2 a cross—section of the installation 10 is shown over the transporters 18. Thereby such a transporter consists of the upper section 32 and the loωer section 34, ωith in betωeeπ located the passage 36 for the substrates 30. In the frames 12 and 14 the supply channels 38 and the discharge channels 40 for the gaseous transport medium 42 are positioned. These gases floω through the holloω bolts 16, through transporter sections 32 and 34 and the communication chambers, 44 and 46, ωhich are located aside the process chamber 48, tαωards the ωide discharge channels 50 and 52 of the respective frames 12 and 14, see also Figure 5. In Figure 3 the hydraulic tensioners 24 are shoωn and ωhereby these ^S E tensioners, urging ωith their ends 54 against the block 26, establish a displacement of the mounting frames 12 and 14 over a very restricted dis¬ tance, for instance 100 μm, in sideward direction. Thereby the mounting bolts 16 through their head-end 56 are also displaced over this distance and therewith also the transporter ends 58. Because the cross-sectional dimensions of the transporter sections 32 and 34 in their mid part 60 are restricted with regard to the length thereof, these sections are stretched by the tension force. A tension force of for instance 1200 kgf, acting on such transporter 18, will cor- respond ωith a stretching of the transporter over 100 μ . In Figure 4 such a transporter arrangement 18 is shoωπ in an enlarged cross-sectional view. During the processing heat is induced by the process gases into the substrate 30. On the other side compressed transport gas as cooling medium, having for instance the very low temperature of approximately -20 C, pas¬ ses through the transporter sections 32 and 34. Heat transfer takes place from the substrate 30 through the hefty whirling transport gas 42 in the narroω passages 64 and 66 aside this sub¬ strate towards each transporter section, whereas the transporter sections take care of the heat transfer towards the cool compressed gas under the establishing of for instance a stabilisation temperature of +3 C in the section 68 near such passages and a temperature of -5 c in the section 70 near the channels 72 for the gaseous transport gas 42. In Figure 6 schematically is shoωn, hoω without the stretching of the transporters 18 each section 32 and 34 thereof is deformed as the re¬ sult of the changes in temperature in these sections, ωith an indicated bending thereof. Thereby combined beπdiπgs of the transporter sections result in a narroωing of the passages 64 and 66 in the mid-position 60, ωhereas these passages have a maximum ωidth near the ends thereof. As a result, a more difficult passing of the substrate takes place through the centre of the passage 36 and such in combination ωith a locally increased heat transfer. Furthermore, great differences are established in the heat transfer through the gases, floωing through the passag—sections ωith an increased ωidth thereof. Consequently, even ωith a restricted heat transfer during the pro¬ cessing, this combination of malfunctiαnings makes a correct functioning OMPI . IPO of the process module impossible. In Figure 7 the transporters 18 are stretched by means of the hy¬ draulic tensioners, ωith such an extent of stretching, that it amply sur¬ passes the local lengthening of the transporter as the result of proces- sing. As a result, approximately the same ωidth of the passages 64 and 66 can be maintained, ωith consequently no local ωorsening of the passing through of the substrate and a constant heat transfer via the gas, ωhir- ling through the passages. In Figure 8 the module 10' is shoωn, ωherεin the combination of sub¬ strates 30 and tape 80 passes through the process module 82. In this module 82, also ωith the add of a r.f. generator 84, plasma etching of the substrates, passing through, takes place. The substrates are supplied by the sender module 86 and in a take— over section 88 are urged onto the tape. The discharge of the substrates occurs in the take-over section 90 and such towards the receiver module 92. At the entrance of the module the tape 80 is ϋnωiπdεd from the roll 94 and fed through the tensioning device 96 to accomplish the stretching of this tape and further along guide roll 98 and through cleaning station 100 fed into the process module. At the exit of the module the tape 80 is guided along the guide roll 102 and fed through the transport device 104, ωhereafter this tape is unmap¬ ped on roll 106. By applying a pulling poωer on the extremely thin tape in this com— bination of tension device 96 and transporter device 104, a stretching of the tape takes place in longitudinal direction thereof. Thereby this stretching surpasses the combination of local lengthe¬ ning of the tape due to the processing, enabling the tape to remain that flat in the module, that a correct resting αf the substrates thereon is maintained. In this installation use can be made of a wide transporter section 32', which is provided ωith a heating element 108, enabling additional heating of this section. As a result, the ωidth of passage 35' remains al¬ most the same over the entire length thereof. Thereby a possible cα— operation ωith the heating element 110, uhich is positioned in the trans¬ porter section 112. In Figure 9 an enlarged vieω is disclosed of a section of a process module 10". OMPI The tape 80 consists of at least part thereof of material, conduc¬ ting electricity. By including this tape together ωith the substrates in an electric circuitry, an attraction force thereof can be established on particles in their vincinity. Because the tape has a greater ωidth than the substrate, it suffi¬ ciently covers the transporter section 32" at the non-processing side. Consequently, particles from the process chamber 114 cannot deposit on this section. Underneath the tape a target arrangement is positioned. By means of ion beams extremely small metal or or other particles 116 can be removed from the target and moved towards the chamber 114, whereby these particle bombard the substrate and partly the tape. If in the process chamber 114 no substrate section is available, then the tape can still function as collector for these particles. In this way an effective metal sputtering can take place in the module. In Figure 10 the module 10' " is suitable for anisotropic etching , whereby both tape, substrates and transporters are connected ωith the r.f. generator 84'. The functioning of these systems is described in the Dutch Paten Application No's 8 302 034 and 8 302 035 of the applicant. Shields 116 function both as sidewall for process slot 28' * * and sideωall for wide discharge channels 118. Through tube 120 process gases are fed into this slot as mini pro— cess chamber, ωhich furthermore is enclosed by shied wall 122. In this wall openings are provided, through ωhich carrier gas 124 enters this chamber. In the chamber the plasma cloud 126 is maintained, ωhich together ωith the carrier gas 124 moves over edges 128 of shields 116 into the discharge channels. Thereby the transport gases 42 act as a barrier 130 for this com¬ bination of gases. Within tha scope of the invention other structures of the transpor¬ ters and the processing slots are possible. Furthermore, the installation can be adapted to meet the demands of particular processings. O PI

Claims: C L A I PI 5 1, Process installation, including a transporter for double floating transport of substrates and means to prevent an unallowable deformation of said transporter as the result of heat transfer during processing. 2. Installation according to Claim .1 , wherein the structure is such, that at least during said processing said transporter is in a stretched condition. 3. Method of said installation according to Claim 2, wherein on said transporter a stretching force is applied in longitudinal direction thereof. 4. Method according to Claim 3, wherein by means of said stretching force, applied on said transporter, a lengthening thereof is established, ωhich is larger than the maximum achievable stretching of said transporter as the result of temperature differences therein. 5. Installation according to Claim 2, wherein a number of successive transporters are located, the two ends of each transporter are secured to separate mounting frames and the structure of said installation is further such, that by means of multiple tensioning devices said frames can be mo¬ ved from each other to such an extent, that said transporters are stret- ched in longitudinal direction. 6. Installation according , to Claim 4, ωherein said tensioning device is an hydraulic tensioner. 7. Installation according to Claim 5, wherein said transporters consist of a section, positioned at the processing side of said substrate passage and a section, positioned at the non-processing side of said passage and both sections are secured to said mounting frames, 8. Installation according to Claim 7, wherein in at least said transporter sections at the non-processing side of said substrate passage a heating element is located, providing a supplementary heating of said sectionsto such an extent, that an unallowable deformation of said section during processing is prevented, 9. Method of said installation according to Claim 8, ωherein during said processing heat is transferred to one side of said transporter sec¬ tion and by means of said supplementary heating of the other side of said section a heat balance in said section is accomplished. 10. Installation according to Claim 2, including a tape as transport means for said substrates. 11. Installation according to Claim 10, including a transport system for said tape for feeding the combination of tape and substrates through successive transporters and process slots. 12. Method of said installation of Claim 11, wherein during said processing said tape carries said substrates through said transporters and process slots. 13. Method according to Claim 12, wherein tensioning means for said tape co-operates ωith transport means for said tape, 14. Installation according to Claim 10, ωherein tensioning means for said tape are positioned at the entrance of a. process module and trans¬ port means for said tape are positioned at the exit of said process modul 15. Tape for use in said installation according to Claim 14, ωherein said tape is roughened at two sides for optimal heat transfer. 16. Tape according to Claim 15, wherein it is oxidized on two sides. 17. Installation according to one of foregoing Claims, wherein said tape together with said substrates function as electrode for at least par thereof, 18, Installation according to Claim 17, wherein in said process module a second electrode is arranged to allow specific processings, 19. Tape, as used in said installation according to Claim 17, wherein at least part of it is that electrically conductive, that it functions as an electrode for at least part thereof. 20. Installation according to Claim 11, including a supply station for gathering of said tape and successive substrates and a discharge section for separation of said tape from said substrates. 21• Installation according to Claim 20, wherein in said supply station and discharge station a pressure adaption takes place to and from the vacuum pressure in said process module. 22. Installation according to Claim 20, ωherein said supply station is structured such, that pre-processing of said substrates takes place and said discharge station is structured such, that post—processing takes place. 23, Installation according to Claim 22, comprising a station for pre-cleaning of said tape, 24, Installation according to Claim 23, comprising a station for post-cleaning of said tape, 25, Installation according to Claim 24, comprising means to enable the re-use of said tape in said process installation, O PI 26, Installation according to one of foregoing Claims, comprising a station for applying a thin adhesive layer on said tape to temporary hold said substrates, 27, t Installation according to one of foregoing Claims, ωhereiπ, as seen in direction of substrate movement,said transporter section at the non-processing side of said substrate has a greater ωidth than said transporter section at the processing side. 28. Installation according to one of foregoing Claims, ωherein said process module includes sections for successive processings of said sub— strates. 29. Method of said installation according to Claim 28, ωherein all processings take place by means of plasma processing, including aπisotrα— pic and isotropic etching. 30. Installation according to one of foregoing Claims, ωherein in between said transporters and said process slots two separation walls are positioned, providing wide discharge channels aside said transporters. 31. Method of said installation according to Claim 30, ωherein during the processing transport gas, escaping from said transporters into said wide discharge channels, establish a gas barrier for process gases, esca— ping along overfloω ends bf said separation walls into said discharge channels. 32. Installation according to Claim 30, comprising a supply tube for process gases in the central section of said process slot and in said tube outhes are provided for urging said process gases towards said substrate passage. 33. Installation according to Claim 32, wherein said process slot as mini process chamber is enclosed by a wall, functioning as electrode, and in said wall channels are arranged for supply of carrier gas towards said slot, 34, Installation according to Claim 33, wherein the structure of said mini chamber is such, that during said processing said carrier gas as cloud escapes towards said discharge channels in between said cloud of process gases and said overflow ends of said separation walls, 35, Installation according to one of foregoing Claims, ωherein the structure and methods of operation include structures and methods, as described in the Dutch Patent Application No. 8 302 035 of the applicant. OMPI

Inventors: BOK EDWARD, BOK, EDWARD
Applicants: BOK EDWARD, BOK, EDWARD
Application year: 1984
Main classification: H05K13
IPC codes: B65H5, H01L21, H05K13