SPOOLING PROCESS FILMS
Spooling apparatus. The apparatus includes an interposer film having a spacer surface and a back surface; a first spacer carried by the interposer film on the spacer surface adjacent a first edge of the interposer film; a second spacer carried by the interposer film on the spacer surface adjacent a second edge of the interposer film, the spacers defining a process-film protective space; and a rotatable core oriented to receive an initial end of the interposer film and to roll up the interposer film with a process film in the process-film protective space with a passive surface of the process film adjacent a surface of the interposer film.
Latest Hewlett Packard Patents:
Process films (including substrates) find many applications in high-technology device manufacture. A process film typically has an active surface and a passive surface. The passive surface can be handled and manipulated with ease, but functional devices, layered coatings, and components may be formed or placed on the active surface, and as a result the active surface may easily be contaminated or damaged by any physical contact during processing. For this reason, various kinds of cassettes and track systems have been developed tier handling process films in ways that do not risk contaminating their active surfaces. In the semiconductor industry, the front-opening unified pod (FOUP) style of standardized wafer cassette handing is widely used to hold silicon wafers; a wafer can be removed from such a pod for processing or measurement as needed by special tools. Similar processes are used for handling thin-film transistor (TFT) glass substrates. In the plastic patterning industry disposable interleaves are sometimes used for handling such process films as touch-screen and membrane switch constituents.
The figures are not drawn to scale. They illustrate the disclosure by examples.
Illustrative examples and details are used in the drawings and in this description, but other configurations may exist and may suggest themselves. Parameters such as voltages, temperatures, dimensions, and component values are approximate. Terms of orientation such as up, down, top, and bottom are used only for convenience to indicate spatial relationships of components with respect to each other, and except as otherwise indicated, orientation with respect to external axes is not critical. For clarity, some known methods and structures have not been described in detail. Methods defined by the claims may comprise steps in addition to those listed, and except as indicated in the claims themselves the steps may be performed in another order than that given. Accordingly, the only limitations are imposed by the claims, not by the drawings or this description.
Roll-to-roll fabrication of active surfaces on process films has been difficult. In complex processes there often are only limited stages in which a film can be rolled up. This is because rolling up the film results in the active side in one wrap of the roll contacting the passive side in a succeeding wrap. In a process involving coating the active surface with a sensitive or adhesive material such as photoresist or barrier coating, the process must continue in-line through cure and bake steps before the film can be rolled up. In addition, even in fabrication stages where rolling up is possible, contamination and mechanical damage introduced by rolling and re-roiling can damage the active surface or components on it. Even in processes where interleaves are used there is a risk of contamination. Moreover, interleaves can introduce static electric charges that not only can damage components on the active surface but also can attract dust and other forms of small particulate contamination. There has been a need for a way to roll up a process film at various fabrication stages without inflicting damage.
As shown in
As shown in
In the example of
Referring now to
A second portion 212 of the interposer film 200 carries second portions 214 and 216 of spacers that rest on the first portion 204 of the interposer film. A third portion 218 of the interposer film 200 carries third portions 220 and 222 of spacers that rest on the second portion 212 of the interposer film.
A length of process film 224 is also rolled up around the core. A first portion 226 of the process film 224 is located in a portion 228 of protective space formed between the spacers. As with the interposer film, the first portion 226 of the process film may be considered as a first layer (first wrap) around the core. A first portion 230 of an active surface of the process film 224 carries various items such as features, coatings, functionalisations, patterns, or components 232A, 232B, 232C, and 232D. These items are installed on, formed in, or otherwise placed on the active surface of the process film. A first portion 234 of a passive surface of the process film 224 is adjacent a first portion 236 of a back surface of the interposer film 200. The first portion 234 of the passive surface of the process film 224 is supported by the first portion 236 of the back surface of the interposer film 200. As will be discussed in more detail presently, the process film is tensioned sufficiently to maintain contact between it and the back surface of the interposer film.
The first portion 228 of the protective space extends between the first portion 236 of the back surface of the interposer film and a second portion 238 of the spacer surface of the interposer film. The spacers are sized such that the protective space fully contains the process film without any contact between the spacer surface of the interposer film and the active surface of the process film.
A second portion 240 of the process film 224 is located in a second portion 242 of the protective space between the spacers. A second portion 24.4 of the passive surface of the process film is adjacent a second portion 246 of the back surface of the interposer film.
A spool thus formed may comprise fewer or more, in some examples many more, wraps than the three wraps of interposer film and two wraps of process film shown in
A length of process film 270 is also rolled up around the core. A first portion 272 of the process film 270 is located in a portion 274 of protective space formed between the spacers. A first portion 276 of an active surface of the process film carries various items such as features, coatings, functionalisations, patterns, or components 278A, 278B, 278C, and 278D. These items are installed on, formed in, or otherwise placed on the active surface of the process film. A first portion 280 of a passive surface of the process film lies adjacent a first portion 282 of a spacer surface of the interposer film. The first portion 280 of the passive surface of the process film is supported by the first portion 282 of the back surface of the interposer film.
A second portion 284 of the process film is located in a second portion 286 of the protective space between the spacers. A second portion 288 of the passive surface of the process film is adjacent a second portion 290 of the spacer surface of the interposer film. Similarly, a third portion 292 of the process film is located in a third portion 294 of the protective space between the spacers with a third portion 296 of the passive surface of the process film adjacent a third portion 298 of the spacer surface of the interposer film.
A length of process film 324 is also rolled up around the core 302. A first portion 326 of the process film 324 is located in a first portion 328 of a protective space formed between the spacers. Various features, coatings, functionatisations, patterns or components 330A, 330B, 330C, and 330D are installed or formed on a first portion 332 of an active surface of the process film. A first portion 334 of a passive surface of the process film is adjacent a first portion 336 of a spacer surface of the interposer film. The first portion 328 of the protective space is bounded by the first portion 336 of the spacer surface and a second portion 338 of the back surface of the interposer film. The process film is tensioned sufficiently to hold its passive surface against the spacer surface of the interposer film such that the active surface of the process film does not contact the back surface of the interposer film.
A second portion 340 of the process film 324 is located in a portion 342 of the protective space between the spacers. A second portion 344 of the passive surface of the process film lies on a second portion 346 of the spacer surface of the interposer film. Similarly, a third portion 348 of the process film 324 is located in a third portion 350 of the protective space. A third portion 352 of the passive surface of the process film lies on a third portion 354 of the spacer surface of the interposer film. As with the other portions of the protective space, the third portion 350 of the protective space lies between the back and spacer surfaces of the interposer film; in this instance, the third portion 350 of the protective space lies between the third portion 354 of the spacer surface of the interposer film and a portion of the back surface of a fourth portion (not shown) of the interposer film.
Returning to the example of
The example of
More than one process film strip may be disposed adjacent a single interposer film. As shown in
A first portion 1022 of a first process film 102.4 is disposed in a protective space between the spacers 1014 and 1020. A second portion 1026 of the first process film 1024 is disposed in a protective space between spacers (not shown) carried by a third portion (not shown) of the interposer film. A passive surface 1028 of the first portion 1022 of the first process film 1024 is adjacent the back surface 1012 of the first portion 1000 of the interposer film. A passive surface 1030 of the second portion 1026 of the first process film 1024 is adjacent a back surface 1032 of the second portion 1010 of the interposer film.
A first portion 1034 of a second process film 1036 is disposed in a protective space between the spacers 1018 and 1020. A second portion 1038 of the second process film 1036 is disposed in a protective space between spacers (not shown) carried by the third portion (not shown) of the interposer film. A passive surface 1040 of the first portion 1034 of the second process film 1036 is adjacent the back surface 1012 of the first portion 1000 of the interposer film. A passive surface 1042 of the second portion 1038 of the second process film 1036 is adjacent the back surface 1032 of the second portion 1010 of the interposer film.
An active surface 1044 of the first portion 1022 of the first process film 1024 may carry components, layers or features (not shown) and is not touched by the interposer film or by any other portions of process film. Similarly, an active surface 1046 of the second portion 1026 of the first process film 1024, an active surface 1048 of the first portion 1034 of the second process film 1036, and an active surface 1050 of the second portion 1038 of the second process film 1036, are untouched by the interposer film or any other portions of process film. For example a component 1052 is disposed on the active surface 1046, a component 1054 is disposed on the active surface 1048, and a component 1056 is disposed on the active surface 1050.
As shown in
In
In the foregoing two examples, the supports comprise spaced-apart parallelepipeds, but in other examples the supports may take the for of segmented strips, continuous strips, or other suitable shapes as desired.
An example of passive-surface process film spooling apparatus generally 1300 is shown in
The process film 1306 may be guided from the first cassette 1302 through the process station 1314 to the second cassette 1316, for example by a first tension roller 1326 between the first cassette 1302 and the process station 1314 and a second tension roller 1328 between the process station 1314 and the second cassette 1316. The first and second tension rollers contact the process film 1306 only on a passive side 1330. Other guides may also be used, such as a draw roller 1332 and a nip wheel 1334 between the tension roller 1326 and the process station 1314, and a draw roller 1336 and a nip wheel 1338 between the process station 1314 and the tension roller 1328.
As the process film unwinds from the spool 1304, the first interposer film 1310 also unwinds and exits the first cassette through the opening 1312. The first interposer film may be wound up to form a spool 1340 on a core 1342. The first interposer film may pass over one or more guides such as a tension roller 1344 as it is unwound from the spool 1304 in the first cassette 1302 and is wound onto the spool 1340. When the process film 1306 and the first interposer film 1310 have been unwound from the spool 1304 and the first interposer film 1310 has been wound onto the spool 1340, the spool 1340 of interposer film may be removed from the apparatus 1300 and reused later, left in situ, or wound back into the cassette without process film for storage.
The second interposer film 1320 may be obtained by unwinding from a spool 1346 on a core 1348. The second interposer film 1320 may pass over one or more guides such as a tension roller 1350 and enters the second cassette 1316 through the opening 1318.
In some examples the opening 1312 may be sealed with a cover 1352 except when the films are being unwound from the spool 1304. Similarly, the opening 1318 may be sealed with a cover 1354 except when the films are being wound up on the spool 1324.
As the process film is wound onto the spool 1324, it may be tensioned by a servo motor 1356 that drives the core 1322. In some examples the process film is also tensioned by one or more of the tension roller 1328, the tension roller 1326, or any other components. In some examples a servo motor (not shown) may be mechanically coupled to the core 1308 and may be used to tension the process film as it is unwound. In some examples a friction brake 1358 applied to a drum 1360 coupled to the core 1308 may be used to tension the process film as it is unwound. Instead of the servo motor 1356, some other kind of motor or a hand crank may be used to provide torque to wind the process and interposer films onto the core 1322.
A servo motor 1362 or other suitable motive device may be used to wind the first interposer film 1310 onto the core 1342 as the process film 1306 and the first interposer film 1310 unwind from the spool 1304. Another servo motor (not shown) or a friction brake 1364 applied to a drum 1366 carried by or coupled to the core 1348 may be used to tension the second interposer film 1320 as it unwinds from the spool 1346.
In some examples a process is carried out on the process film as the film is being wound up (1508). This procedure has been discussed previously in connection with
In other examples the process is carried out after the films have been wound up (1510). As one example, the spooled-up film may be placed into a process station and the process performed on the entire spool at once. An interposer film that is porous or perforated as described previously may be used in this instance.
In some examples the method continues with providing a second interposer film (1608). The process film is spooled with the second interposer film, a passive surface of the process film adjacent a surface of the second interposer film (1610). The process film may be tensioned at a lesser tension than at least one of the first and second interposer films (1612).
In other examples, instead of spooling up the first interposer film, the process film is fed back to the first interposer film and is again spooled up with the first interposer film (1614), and no second interposer film is needed.
A spool of process film disposed in the protective spaces provided by the interposer film and its spacers, and with an active surface of the process film thereby protected from any contact with either the interposer film or other layers of the process film, may be enclosed in a cassette. A cassette containing such a spool can easily be transported without damaging the process film.
The interposer film may be fabricated of any thin compliant material, such as plastic, paper, metal, glass, composite, or the like.
During spooling, the interposer film can be tensioned to form the spool, and very little tension need be applied to the process film, further protecting it. The core may be rotated by a servo motor (for example, as shown in
Apparatus and methods as described make it possible to handle process films in such a way that active surfaces of the films are not touched during unwinding or winding up or white spooled. Wound-up spools of process film can easily be protected from contamination by dust and other damaging debris during transport or any time the process film is not being processed. This flexibility allows different processes to be run at different rates. Some processing, for example long-term low-temperature baking, may be done while the film is spooled up. If the spool of film is enclosed in a cassette, the cassette can readily be transported between facilities and processes outside of a clean environment. Fabrication processes can be broken down into a smaller granularity, allowing for optimization and easy process development at pilot scale or customization at volume scale. The same system can handle films of various widths, thicknesses, and moduli. Films can be spooled with independent tension between the spool formation and tension of the film, and films can be stored with low tension applied, leading to a reduction in mechanical deformation during storage. Cassettes can carry tracking, content, and process data any of which can be read without reference to the actual film, facilitating efficient process management and quality control.
Claims
1. Spooling apparatus comprising:
- an interposer film having a spacer surface and a back surface;
- a first spacer carried by the interposer film on the spacer surface adjacent a first edge of the interposer film;
- a second spacer carried by the interposer film on the spacer surface adjacent a second edge of the interposer film, the spacers defining a process-film protective space; and
- a rotatable core oriented to receive an initial end of the interposer film and to roll up the interposer film with a process film in the process-film protective space with a passive surface of the process film adjacent a surface of the interposer film.
2. The apparatus of claim 1 wherein the spacers are selected from among a segmented strip, a compliant strip, and a plurality of spacer elements.
3. The apparatus of claim 1 wherein the interposer film comprises at least one of a surface-textured material, a mesh, an anisotropically-compliant material, and one or more transverse stiffening elements.
4. The apparatus of claim 1 Wherein one or more of the interposer film, the first spacer, and the second spacer comprise gas-permeable material.
5. The apparatus of claim 1 and further comprising a plurality of supports carried by the interposer film and disposed to support an active surface of the process film at points remote from any active portions of the active surface of the process film.
6. The apparatus of claim 1 and further comprising one or more additional spacers carried by the interposer film between the first and second spacers, the additional spacers dividing the protective space into protective regions each sized to accommodate a process film.
7. The apparatus of claim 1 and further comprising:
- an interposer film core on which the interposer film is rolled up and from which the interposer film may be unrolled; and
- a tensioner coupled to the interposer film core.
8. The apparatus of claim 1 and further comprising an interposer film tension roller disposed to feed the interposer film to the rotatable core.
9. The apparatus of claim 1 and further comprising a motor coupled to the rotatable core.
10. The apparatus of claim 1 and further comprising:
- a cassette enclosing the rotatable core, the cassette sized to accommodate a spool of interposer film and process film rolled up on the rotatable core, a wall of the cassette defining an opening sized to accommodate the interposer and process films; and
- a removable cover on the opening.
11. A method of processing process films, the method comprising:
- providing an interposer film having a spacer surface and a back surface, the spacer surface having a first spacer adjacent a first edge of the interposer film and a second spacer adjacent a second edge of the interposer film, and at least one protective space defined between the first and second spacers; and
- winding a process film and the interposer film onto a core with the process film disposed in the protective space between the first and second spacers and a passive surface of the process film adjacent a surface of the interposer film.
12. The method of claim 11 wherein winding the process and interposer films onto the core comprises:
- tensioning the interposer film; and
- tensioning the process film at a lesser tension than the interposer film.
13. The method of claim 11 and further comprising carrying out a process on the process film after the film has been wound onto the core.
14. A method of processing process films, the method comprising:
- providing unprocessed process film spooled with a first interposer film, a passive surface of the process film adjacent a surface of the first interposer film;
- unwinding the films;
- feeding the process film through a process station; and
- spooling the interposer film.
15. The method of claim 14 and further comprising:
- providing a second interposer film; and
- spooling the process film with the second interposer film, a passive surface of the process film adjacent a surface of the second interposer film.
16. The method of claim 15 and further comprising tensioning the process film at a lesser tension than at least one of the first and second interposer films.
Type: Application
Filed: May 31, 2012
Publication Date: Mar 19, 2015
Applicant: Hewlett-Packard Development Company, L.P. (Houston, TX)
Inventors: John Christopher Rudin (Bristol Bristol), Alejandro de la Fuente Vombrock (San Carla, CA), Richard Leonard Hall (Kettering Northants), Stuart Richard Wilford (Kettering Northants), Anthony George Bird (Old, Northants), Stephen Robert Spruce (Hugill Close)
Application Number: 14/395,767