1. Field of the Invention
The current invention relates to transport systems and methods for conveying articles along a conveyance path, and in some embodiments to conveying substrates for the manufacture of electronic devices in a fabrication facility.
2. Related Art
Transport systems are widely employed in industrial manufacturing facilities to convey articles between work stations. Originally, these systems were manual and workers moved articles by hand or by cart. Modern factories have developed specialized equipment to convey articles automatically. In particular, semiconductor fabrication facilities currently use automated transport systems to move semiconductor wafers during the manufacturing process. Typically, a batch of wafers may be conveyed together in a container known as a FOUP. Semiconductor wafer manufacturers have sought to increase manufacturing productivity by using transport systems that efficiently convey wafers from machine to machine without exposing the wafers to excessive contamination, vibration or to excessive acceleration and deceleration forces. Similar efforts toward increased productivity have been directed toward the fabrication of diverse electronic devices, ranging from substrates for the manufacture of video displays to substrates for the manufacture of energy conversion devices (e.g. photovoltaic cells).
Existing transport systems often employ vehicle-based devices to eliminate vibrations, but the capacity of such a system is limited by the number of vehicles available. To resolve this, transporters are used in which articles are, for example, directly conveyed across the horizontal surface of a transport belt on rollers, or directly on the rollers. One such transport system is shown in
Another problem with existing transport systems used in the semiconductor wafer manufacturing industry is the difficulty of changing or turning the direction of conveyance of an article, such as a FOUP, without momentarily stopping its motion.
There are, therefore, need for improved systems and methods for conveying articles in manufacturing facilities.
The present invention includes, in various embodiments, a transport system for moving articles along a conveyance path that includes straight, horizontal, inclined, and/or declined sections. The articles are conveyed between support protrusions extending from compliant horizontal belts. The compliant feature of the horizontal belts creates a shock-absorbing effect such that the articles being transported experience reduced vibration during the conveyance. The support protrusions may also have a compliant feature, further reducing vibrations during conveyance of the article. These configurations allows the weight of the articles to be partially decoupled from the uneven surfaces across which the horizontal belts travel, resulting in less variation in height of the transported articles during transport as compared to the prior art.
In various embodiments, the shock-absorbing effect of the compliant horizontal belts allows articles, such as Front Opening Unified Pods (FOUPs) including semiconductor wafers, to be transported at greater speeds than in the prior art while still staying within vibration limits. Systems of the invention, therefore, typically reduce the vibration experienced by a FOUP or other article during transport relative to the prior art.
In various embodiments, articles are supported between first and second horizontal belts by one or more support protrusions extending from the first horizontal belt and the second horizontal belt. The weight of the articles is transferred through the support protrusions to the compliant horizontal belts. In various embodiments, the support protrusions, compliant horizontal belts, and rollers are configured to selectively engage and disengage the articles. In some embodiments, the support protrusions are specifically configured to support FOUPs used to transport semiconductor wafers within semiconductor fabrication facilities. In other embodiments, the support protrusions are specifically configured to support substrates for the manufacture of electronic displays (e.g. flat screen displays), energy conversion devices (e.g. photovoltaic cells) or other objects.
A transport system optionally includes several transport sections each including separate compliant horizontal belts. Furthermore, within an individual transport section the compliant horizontal belts are optionally configured in an inclined or declined path, allowing the elevation (height) above ground of the article to be changed during the conveyance. Individual control over belts may also be used to provide for tilting of the conveyance path.
Various embodiments of the invention include a system comprising a first horizontal belt and a second horizontal belt disposed on either side of a conveyance path and configured to convey an article along the conveyance path, a plurality of horizontal rollers configured to guide the first horizontal belt and the second horizontal belt, and a plurality of support protrusions extending from the first horizontal belt and from the second horizontal belt, the plurality of support protrusions configured to support a weight of the article.
Various embodiments of the invention include a transport belt comprising a first surface configured to be coupled to a horizontal roller, the horizontal roller being configured to drive the transport belt in a conveyance path, a support protrusion configured to support the weight of an article being conveyed along the conveyance path by the transport belt, and a compliant material configured to allow the support protrusion to move in response to forces from the article, thus allowing the transport belt to operate as a shock absorber.
Various embodiments of the invention include a method comprising loading an article on a conveyance section, the conveyance section including a first horizontal belt and a second horizontal belt and a plurality of horizontal rollers configured to guide the first horizontal belt and the second horizontal belt, conveying the article along a conveyance path using the first horizontal belt and the second horizontal belt, and unloading the article.
In certain embodiments, the weight of the article between two belts may be at least partially borne by an air bearing. In select embodiments, a three-point kinematic interface can be used to load and/or unload an article.
In some aspects, a system comprises a first belt and a second belt disposed on either side of a conveyance path and configured to convey a FOUP along the conveyance path. The first belt and the second belt are separated by a distance configured for placement of the FOUP between them. A plurality of approximately horizontal rollers is configured to guide the first belt and the second belt, and the FOUP has a lateral freedom of movement of 110 millimeters or less between the belts. A plurality of support protrusions extends from the first belt and from the second belt; the plurality of support protrusions is configured to support the weight of the FOUP.
In other aspects, a system includes a substrate used for manufacturing a device, and a first belt and a second belt disposed on either side of a conveyance path. The belts are configured to convey the substrate along the conveyance path, and the first belt and the second belt are separated by a distance configured for placement of the substrate between the belts. A plurality of approximately horizontal rollers is configured to guide the first belt and the second belt, and a plurality of support protrusions extend from the first belt and from the second belt. The protrusions are configured to support the weight of the substrate.
In further aspects, system includes a first belt and a second belt disposed on either side of a conveyance path and configured to convey a FOUP along the conveyance path. The belts are separated by a distance configured for placement of the FOUP between them, and a plurality of approximately horizontal rollers is configured to guide the belts. A plurality of support protrusions extends from each of the belts; these protrusions are configured to support the weight of the FOUP. A three-point kinematic interface is configured to manipulate the FOUP.
In other aspects, a method comprises loading an article on a transport section. The transport section includes a first horizontal belt and a second horizontal belt, and the belts are separated by a distance configured for placement of the article between them. A plurality of horizontal rollers is configured to guide the belts, and a plurality of support protrusions extends from each of the belts. The protrusions are configured to support a weight of the article. The method also includes conveying the article along a conveyance path using the belts.
Further aspects include a method comprising the loading of an article on a transport section using a three-point kinematic interface. The transport section includes a first horizontal belt and a second horizontal belt, and the belts are separated by a distance configured for placement of a FOUP between them. A plurality of horizontal rollers is configured to guide the belts. The method includes conveying the article along a conveyance path using the belts and unloading the article.
Additional aspects include a system comprising means for loading an article on a transport section. The transport section includes a first horizontal belt and a second horizontal belt, and the belts are separated by a distance configured for placement of the article between them. A plurality of horizontal rollers is configured to guide the belts. The system also includes a means for conveying the article along a conveyance path using the belts, and means for unloading the article. In certain embodiments, the article may include a FOUP, a semiconductor wafer, or a substrate used in the manufacture of a device.
Still further aspects include a system comprising a first belt and a second belt disposed on either side of a conveyance path and configured to convey an article along the conveyance path. The belts are separated by a distance configured for placement of a FOUP between them, such that the FOUP has a lateral freedom of movement of 110 millimeters or less between the belts. Also included is a plurality of approximately horizontal rollers configured to guide the belts, and a plurality of support protrusions extending from the belts. The plurality of support protrusions are configured to support the weight of the article, and at least one of the protrusions includes an article supporting surface that is disposed below part of the first belt.
In additional aspects, a system includes a first belt and a second belt disposed on either side of a conveyance path and configured to convey an article along the conveyance path. The belts are separated by a distance configured for the placement of a FOUP between them, and a plurality of approximately horizontal rollers is configured to guide the belts. A plurality of support protrusions extend from the belts. These protrusions are configured to support the weight of the article, and at least one support protrusion includes an article supporting surface that is disposed below part of the first belt. The system also includes a three-point kinematic interface configured to unload the article from the belts.
Further aspects include a system comprising a first horizontal belt and a second horizontal belt disposed on either side of a conveyance path. The belts are configured to convey an article along the conveyance path. A plurality of approximately horizontal rollers is configured to guide the belts, and a plurality of support protrusions extend from the belts. These protrusions are configured to support the weight of the article.
Various embodiments of the invention include improved systems and methods for automatically transporting articles such as FOUPs, substrates for the manufacture of electronic devices, or other articles. For convenience, drawings in this description show embodiments directed toward the transport of FOUPs. However, the invention is not limited to the transport of FOUPs. Some embodiments include the use of compliant horizontal belts that propel articles in a conveyance direction. In comparison with the prior art, the use of compliant horizontal belts allows for more even support of articles and, thus, improved vibration management. In various embodiments, the use of compliant horizontal belts allows the transport of articles along straight, inclined, declined, and/or dynamically changing conveyance paths.
The compliant horizontal belts (transport belts) are optionally disposed between the horizontal rollers and the articles to be transported. In some embodiments, the horizontal belts include a compliant material configured to reduce vibration of articles during transport. This reduced vibration may allow the transport of articles at greater speeds than with prior art systems, while staying within vibration limits.
In various embodiments, articles are supported by protrusions extending approximately horizontally from the compliant horizontal belts. The support protrusions are optionally configured for supporting specific types of articles. For example, some embodiments include support protrusions configured for supporting a FOUP. The size and spacing of the support protrusions is optionally configured such that more than one protrusion from each compliant horizontal belt provides support to an article. In some instances, the support protrusions include a low friction material such as Teflon™ that will allow an article to move slightly on the support protrusions. In some embodiments, the support protrusions include a high friction material that reduces slippage during high acceleration and/or deceleration.
In various embodiments, the compliant horizontal belts include a material configured to flex, deform, bend or otherwise change shape when an article is placed on the support protrusions. For example, in some embodiments the compliant materials are configured to allow a support protrusion to move vertically while supporting the weight of a FOUP during a conveyance.
In various embodiments, the compliant horizontal belts are supported by a low friction sliding surface, an array of finely spaced horizontal rollers or the like. Some embodiments include a clamp, retaining lip or a capture lip configured to restrain movement of articles relative to the transport system. This clamp, retaining lip or capture lip may be part of a support protrusion, be a separate protrusion coupled to a compliant horizontal belt, or be attached to a stationary supporting structure. The clamp, retaining lip or a capture lip is optionally configured to restrain the article during transport and, thus, prevent tipping, sliding or other unintended displacement during acceleration and deceleration.
Conveyance paths determined by the location of the horizontal rollers and/or the compliant horizontal belts may be straight, inclined, declined, and/or dynamically variable. For example, in some embodiments, the horizontal rollers are coupled to movable mounts and are configured to move between various different positions in order to change a conveyance path. In some embodiments the horizontal rollers are configured to move while conveying articles.
Some embodiments feature an air bearing between the belts, often provided by an air bearing generator. The air bearing can provide additional support to the article being transported, and may be particularly useful when transporting wide or flexible articles. Aspects of the air bearing feature non-contact support of the article.
Select embodiments include various apparatus and methods for loading and unloading articles. Loading and/or unloading of articles may optionally be performed with a specially designed interface. For example, by defining a specific mechanical, electrical and software interface, a variety of devices may directly access FOUPs on the transport belts. Example interfaces include a mechanical interface such as the kinematic interface defined by the trade organization SEMI in the document number E57-0600 entitled “Mechanical Specification for Kinematic Couplings used to Align and Support 300 mm Wafer Carriers,” and the electrical interface and software communications interface defined by the SEMI standard E84-0305 entitled “Specification for Enhanced Carrier Handoff Parallel I/O Interface.” The kinematic interface features three kinematic coupling pins on a kinematic mount and configured to mate with three corresponding depressions disposed on the bottom of the FOUP 170 when the FOUP 170 is placed in proper alignment with the kinematic mount. It will be appreciated that the FOUP can also be manipulated from a standard handle on the top of the FOUP. Such a handle is illustrated on the top of FOUP 170 in
First Horizontal Belt 210 and Second Horizontal Belt 220 are each driven separately or jointly in the Conveyance Direction 280 by a plurality of horizontal rollers such as Horizontal Rollers 110 in
In typical embodiments, one or more Support Protrusions 230 is attached to each of First Horizontal Belt 210 and to Second Horizontal Belt 220. Support Protrusions 230 extend from First Horizontal Belt 210 and from Second Horizontal Belt 220, and are configured to support the weight of conveyed articles.
In typical embodiments, Support Protrusions 230 are configured to support the article being transported. Support Protrusions 230 optionally include a low friction coating (not shown), and may be optionally comprised of a low friction material such as Teflon™ to reduce friction between the Support Protrusions 230 and the article during transport.
In some embodiments, the deflection of Support Protrusions 230 under the weight of an article, such as FOUP 170, causes part of an article to be transported below part of First Horizontal Belt 210 and Second Horizontal Belt 220, as shown in
The embodiment shown in
In some embodiments, Air Bearing Generators 620 are configured to provide support in a central region of the article being transported. In various embodiments, the article comprises a substrate including glass, polymer, or semiconductor material. The article may also comprise substrates for the manufacture of liquid crystal, organic light emitting diode or other types of display devices, a memory substrate (such as a hard drive platter substrate or an optical storage device substrate), a photovoltaic device substrate, a battery substrate, or the like. By supporting the central region of the article, Air Bearing Generators 620 may reduce stress on the article, and prevent damage or breakage due to bending caused by uneven support across the width of the article between the transport, belts. In some embodiments, the Air Bearing Generators 620 may support an article such as a substrate characterized by an area less than 1 square meter, between 1 square meter and 5 square meters, between 5 square meters and 6 square meters, or between 6 square meters and 7 square meters.
Air Bearing. Generators 620 may also reduce physical contact between the conveyance section 240 and the article 170 in comparison with alternative support members such as rollers, consequently reducing friction and vibration. Reduced contact and friction may also reduce contamination of the article and the ambient environment, for example by minimizing scrubbing.
In some embodiments, Transport Section 240 (configured to form a straight path) and/or Transport Section 710 (configured to form an inclined or a declined path) may be coupled to a transport section using vertically-oriented belts. Thus, a transport system configured to convey articles such as FOUP 170 may comprise combinations of horizontal belts of the present invention with vertically-oriented belts. In one example, a transport system may be configured with a first section comprising vertically-oriented belts to convey articles along a path of constant elevation above the ground, a second section comprising a Transport Section 710 to raise or lower the elevation of the conveyed article, followed by a third section comprising vertically-oriented belts to continue the conveyance of the articles along a path of constant elevation. In optional embodiments, each of the first, second, and third sections described above may be any one of Transport Section 240, Transport Section 710, or a transport section comprising vertically-oriented belts.
In a Transport Article Step 820, the article loaded in Load Article Step 810 is conveyed in the conveyance direction. This conveyance is optionally performed at a greater speed and/or a lower vibration rate than is possible in systems of the prior art. Transport Article Step 820 optionally includes directing the article along an inclined, declined or tilted path such as that illustrated in
In an Unload Article Step 830, the article is removed from the transport system. This removal optionally occurs at a location configured for loading and/or unloading of the article, as discussed elsewhere herein.
In some embodiments, Load Article Step 810 and/or Unload Article Step 830 can optionally be performed using a three point kinematic interface, as described elsewhere herein.
In a Transport Article Step 910, an article, such as FOUP 170, is transported as in Transport Article Step 820. In Adjust Conveyance Path Step 920, a conveyance path for the article is changed by moving First Horizontal. Belt 210 and/or Second Horizontal Belt 220. This movement may be in the horizontal or vertical plane, or even in a combination of horizontal and vertical planes. In Transport Article Step 930, the article is again conveyed, as in Transport Article Step 910.
In a Transport Article Step 1010, an article, such as FOUP 170, is transported using a first transport section comprising a horizontal belt as described above. In a Transition to Next Transport Section Step 1020, the article is transferred to a second transport section, optionally comprising a vertically-oriented belt. In Transport Article Step 1030, the article is again conveyed, this time using the second transport section. Transfer of the article between sections may be enhanced by the use of one or more air bearings.
The Air Bearing Generator 1110 may optionally be configured to output a significantly reduced Air Stream 1120 or no Air Stream 1120 when the Article 1111 is not in a path of the Air Stream 1120. For example, the Air Bearing Generator 1110 may be configured to only output the Air Stream 1120 directly upward if the Article 1111 is above the Air Bearing 1040, and to output a reduced Air Stream 1120 when there is no Article 1111 above the Air Bearing 1040. In some embodiments, turbulent limited orifices, such as those described in U.S. Pat. No. 6,523,572 entitled “Apparatus for Inducing Forces by Fluid Injection” which is incorporated herein by reference, may be used to limit the Air Stream 1120 when there is no Article 1111 above the Air Bearing 1040.
Several embodiments are specifically illustrated and/or described herein. However, it will be appreciated that modifications and variations are covered by the above teachings and within the scope of the appended claims without departing from the spirit and intended scope thereof. For example, while the transportation of FOUPs in semiconductor manufacturing have been used herein as an illustrative example, systems and methods of the invention may be configured for transporting alternative materials, such as for example, substrates for the manufacture of liquid crystal, plasma, organic light emitting diode or other types of display devices. Further, the compliant horizontal belts and horizontal rollers discussed herein need not be perfectly horizontal.
The embodiments discussed herein are illustrative of the present invention. As these embodiments of the present invention are described with reference to illustrations, various modifications or adaptations of the methods and or specific structures described may become apparent to those skilled in the art. All such, modifications, adaptations, or variations that rely upon the teachings of the present invention, and through which these teachings have advanced the art, are considered to be within the spirit and scope of the present invention. Hence, these descriptions and drawings should not be considered in a limiting sense, as it is understood that the present invention is in no way limited to only the embodiments illustrated.
This application claims the benefit of U.S. Provisional Patent Application 60/840,169 titled “High Speed Transporter Including Horizontal Belt,” filed Aug. 25, 2006, and 60/840,131, “High Speed Transfers Between Transport Devices” also filed on Aug. 25, 2006, both of which are incorporated herein by reference. This application is related to U.S. patent application Ser. No. 11/406,569, titled “Transport System Including Vertical Rollers,” filed Apr. 18, 2006, which is hereby incorporated by reference.
Number | Date | Country | |
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60840169 | Aug 2006 | US | |
60840131 | Aug 2006 | US |