POSITIONING ARRANGEMENT FOR A SUBSTRATE CARRIER AND A MASK CARRIER, TRANSPORTATION SYSTEM FOR A SUBSTRATE CARRIER AND A MASK CARRIER, AND METHODS THEREFOR
20190368024 · 2019-12-05
Inventors
- Matthias HEYMANNS (Münster, DE)
- Oliver HEIMEL (Wabern, DE)
- Stefan BANGERT (Steinau, DE)
- Jürgen HENRICH (Limeshain, DE)
- Andreas SAUER (Großostheim, DE)
- Tommaso Vercesi (Aschaffenburg, DE)
Cpc classification
C23C14/568
CHEMISTRY; METALLURGY
H01L21/67712
ELECTRICITY
H01L21/6776
ELECTRICITY
International classification
C23C14/04
CHEMISTRY; METALLURGY
Abstract
A positioning arrangement for positioning a substrate carrier and a mask carrier in a vacuum chamber is described. The positioning arrangement comprising a first track extending in a first direction and configured transportation of the substrate carrier configured for holding a substrate having a substrate surface, a second track extending in the first direction and configured for transportation of the mask carrier, wherein the first track and the second track are offset by an offset distance in a plane coplanar with the substrate surface, and a holding arrangement configured for holding the mask carrier, wherein the holding arrangement is arranged between the first track and the second track.
Claims
1. A positioning arrangement for positioning a substrate carrier and a mask carrier in a vacuum chamber, comprising: a first track extending in a first direction and configured for transportation of the substrate carrier configured for holding a substrate having a substrate surface; a second track extending in the first direction and configured for transportation of the mask carrier, wherein the first track and the second track are offset by an offset distance in a plane coplanar with the substrate surface; and a holding arrangement configured for holding the mask carrier, wherein the holding arrangement is arranged between the first track and the second track.
2. The positioning arrangement according to claim 1, wherein the first track is configured for contactless transportation of the substrate carrier, and wherein the second track is configured for contactless transportation of the mask carrier.
3. The positioning arrangement according to claim 2, wherein the holding arrangement comprises at least one holding element configured to be movable in a moving direction being different to a substrate transport direction.
4. The positioning arrangement according to claim 1, further comprising an alignment system configured for aligning the substrate carrier relative to the mask carrier.
5. The positioning arrangement according to claim 1, wherein the first track comprises a first guiding structure and a first drive structure which are spaced apart by a first distance.
6. The positioning arrangement according to claim 1, wherein the second track comprises a second guiding structure and a second drive structure which are spaced apart by a second distance.
7. The positioning arrangement according to according to claim 1, wherein the first track comprises a first guiding structure and a first drive structure which are spaced apart by a first distance, wherein the second track comprises a second guiding structure and a second drive structure which are spaced apart by a second distance, and wherein the first distance is smaller than the second distance.
8. The positioning arrangement according to claim 5, wherein the first guiding structure is a first magnetic guiding structure and the first drive structure is a first magnetic drive structure, and/or wherein the second guiding structure is a second magnetic guiding structure and the second drive structure is a second magnetic drive structure.
9. A transportation system for transporting a substrate carrier and a mask carrier in a processing system, comprising: a first track extending in a first direction and for contactless transportation of the substrate carrier configured for holding a substrate having a substrate surface; and a second track extending in the first direction and configured for contactless transportation of the mask carrier, wherein the first track and the second track are offset by an offset distance in a plane coplanar with the substrate surface.
10. The transportation system according claim 9, wherein the first track comprises a first guiding structure and a first drive structure which are spaced apart by a first distance.
11. The transportation system according to claim 9, wherein the second track comprises a second guiding structure and a second drive structure which are spaced apart by a second distance.
12. The transportation system according to claim 10, wherein the first distance is smaller than the second distance.
13. A vacuum processing system comprising: a vacuum processing chamber having a positioning arrangement for positioning a substrate carrier and a mask carrier in a vacuum chamber, the positioning arrangement comprising: a first track extending in a first direction and configured for transportation of the substrate carrier configured for holding a substrate having a substrate surface; a second track extending in the first direction and configured for transportation of the mask carrier, wherein the first track and the second track are offset by an offset distance in a plane coplanar with the substrate surface, and a holding arrangement configured for holding the mask carrier, wherein the holding arrangement is arranged between the first track and the second track; and at least one further chamber having a transportation system for transporting a substrate carrier and a mask carrier in a processing system, the transportation system comprising: a first track extending in a first direction and for contactless transportation of the substrate carrier configured for holding a substrate having a substrate surface; and a second track extending in the first direction and configured for contactless transportation of the mask carrier, wherein the first track and the second track are offset by an offset distance in a plane coplanar with the substrate surface.
14. A method for positioning a substrate carrier relative to a mask carrier, comprising: positioning the substrate carrier in a first position by using a first track configured for contactless transportation of the substrate carrier; positioning the mask carrier in a second position by using a second track configured for contactless transportation of the mask carrier; holding the mask carrier by using an holding arrangement arranged between the first track and the second track; and aligning the substrate carrier relative to the mask carrier.
15. A method for transporting a substrate carrier and a mask carrier through a processing system, comprising: transporting the substrate carrier on a first track configured for contactless transportation of the substrate carrier configured for holding a substrate having a substrate surface; and transporting the mask carrier on a second track configured for contactless transportation of the mask carrier, wherein the first track and the second track are offset by an offset distance in a plane coplanar with the substrate surface.
16. The positioning arrangement according to claim 4, wherein the first track comprises a first guiding structure and a first drive structure which are spaced apart by a first distance.
17. The positioning arrangement according to claim 4, wherein the second track comprises a second guiding structure and a second drive structure which are spaced apart by a second distance.
18. The positioning arrangement according to claim 5, wherein the second track comprises a second guiding structure and a second drive structure which are spaced apart by a second distance.
19. The positioning arrangement according to claim 6, wherein the first guiding structure is a first magnetic guiding structure and the first drive structure is a first magnetic drive structure, and/or wherein the second guiding structure is a second magnetic guiding structure and the second drive structure is a second magnetic drive structure.
20. The positioning arrangement according to claim 7, wherein the first guiding structure is a first magnetic guiding structure and the first drive structure is a first magnetic drive structure, and/or wherein the second guiding structure is a second magnetic guiding structure and the second drive structure is a second magnetic drive structure.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments. The accompanying drawings relate to embodiments of the disclosure and are described in the following:
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DETAILED DESCRIPTION OF EMBODIMENTS
[0026] Reference will now be made in detail to the various embodiments, one or more examples of which are illustrated in each figure. Each example is provided by way of explanation and is not meant as a limitation. For example, features illustrated or described as part of one embodiment can be used on or in conjunction with any other embodiment to yield yet a further embodiment. It is intended that the present disclosure includes such modifications and variations.
[0027] Within the following description of the drawings, the same reference numbers refer to the same or to similar components. Generally, only the differences with respect to the individual embodiments are described. Unless specified otherwise, the description of a part or aspect in one embodiment can apply to a corresponding part or aspect in another embodiment as well.
[0028] Before various embodiments of the present disclosure are described in more detail, some aspects with respect to some terms and expressions used herein are explained.
[0029] In the present disclosure, a positioning arrangement is to be understood as an arrangement which is configured for positioning of a carrier, particularly a substrate carrier and/or a mask carrier. In particular, a positioning arrangement as described herein can be understood as an arrangement which is configured for moving a substrate carrier and/or a mask carrier along a transportation track. More specifically, the positioning arrangement can be configured for positioning the substrate carrier in a first position by moving the substrate carrier along a first track. Additionally, the positioning arrangement can be configured for positioning the mask carrier in a second position by moving the mask carrier along a second track. For instance, the first track and the second track can be configured for contactless transportation. Accordingly, it is to be understood that the positioning arrangement as described herein is configured for moving the substrate carrier and the mask carrier independently from each other, such that the substrate carrier and the mask carrier can be positioned relatively to each other, e.g. for aligning the substrate carrier with the mask carrier.
[0030] In the present disclosure, a substrate carrier is to be understood as a carrier which is configured for holding a substrate as described herein, particularly a large area substrate. Typically, the substrate held or supported by the substrate carrier includes a front surface and a back surface, wherein the front surface is a surface of the substrate being processed, for example on which a material layer is to be deposited.
[0031] The term substrate as used herein may particularly embrace substantially inflexible substrates, e.g., glass plates and metal plates. However, the present disclosure is not limited thereto and the term substrate can also embrace flexible substrates such as a web or a foil. The term substantially inflexible is understood to distinguish over flexible. Specifically, a substantially inflexible substrate can have a certain degree of flexibility, e.g. a glass plate having a thickness of 0.5 mm or below, wherein the flexibility of the substantially inflexible substrate is small in comparison to the flexible substrates. According to embodiments described herein, the substrate may be made of any material suitable for material deposition. For instance, the substrate may be made of a material selected from the group consisting of glass (for instance soda-lime glass, borosilicate glass etc.), metal, polymer, ceramic, compound materials, carbon fiber materials or any other material or combination of materials which can be coated by a deposition process.
[0032] According to some embodiments, the substrate can be a large area substrate and may be used for display manufacturing. For instance, a large area substrate can have a main surface with an area of 0.5 m.sup.2 or larger, particularly of 1 m.sup.2 or larger. In some embodiments, a large area substrate can be GEN 4.5, which corresponds to about 0.67 m.sup.2 of substrate (0.730.92m), GEN 5, which corresponds to about 1.4 m.sup.2 of substrate (1.1 m1.3 m), GEN 7.5, which corresponds to about 4.29 m.sup.2 of substrate (1.95 m2.2 m), GEN 8.5, which corresponds to about 5.7 m.sup.2 of substrate (2.2 m2.5 m), or even GEN 10, which corresponds to about 8.7 m.sup.2 of substrate (2.85 m3.05 m). Even larger generations such as GEN 11 and GEN 12 and corresponding substrate areas can similarly be implemented.
[0033] In the present disclosure, a mask carrier is to be understood as a carrier which is configured for holding a mask. For instance, the mask may be an edge exclusion mask or a shadow mask. An edge exclusion mask is a mask which is configured for masking one or more edge regions of the substrate, such that no material is deposited on the one or more edge regions during the coating of the substrate. A shadow mask is a mask configured for masking a plurality of features which are to be deposited on the substrate. For instance, the shadow mask can include a plurality of small openings, e.g. a grid of small openings.
[0034] In the present disclosure, a track configured for contactless transportation is to be understood as a track which is configured for contactless transportation of a carrier, particularly a substrate carrier or a mask carrier. The term contactless can be understood in the sense that the weight of the carrier, e.g. of the substrate carrier or mask carrier, is not held by a mechanical contact or mechanical forces, but is held by a magnetic force. In particular, the carrier can be held in a levitating or floating state using magnetic forces instead of mechanical forces. For example, in some implementations, there can be no mechanical contact between the carrier and the transportation track, particularly during levitation, movement and positioning of the substrate carrier and/or mask carrier.
[0035] In the present disclosure, the expression offset by an offset distance in a plane coplanar with the substrate surface is to be understood as a configuration in which an offset distance is provided in a direction of the substrate surface extension. Accordingly, the expression that the first track and the second track are offset by an offset distance in a plane coplanar with the substrate surface can be understood in that a distance between the first track and the second track is provided, wherein the distance is coplanar with the substrate surface. However, it is to be understood that the first track and the second track do not have to be arranged in plane coplanar with the substrate surface. In particular, e.g. from
[0036]
[0037] Accordingly, beneficially an improved apparatus for positioning a substrate carrier and a mask carrier is provided. In particular, by providing a positioning arrangement which is configured for contactless transportation of a substrate carrier and the mask carrier, beneficially a generation of particles, e.g. generated due to a mechanical contact between the carriers and the transportation tracks, can be avoided during transportation and alignment of the carriers. Accordingly, embodiments described herein provide for an improved purity and uniformity of the layers deposited on the substrate, in particular since a particle generation is minimized when using the contactless levitation, transportation and/or alignment. Further, by providing a positioning arrangement wherein a first track for a substrate carrier is offset by an offset distance with respect to a second track for a mask carrier, structural advantages for providing further structural elements, e.g. a holding arrangement for a mask carrier, can be provided.
[0038] According to embodiments which can be combined with any other embodiments described herein, the offset distance D may be between a lower limit of D100 mm, particularly a lower limit of D150 mm, more particularly a lower limit of D200 mm and an upper limit of D250 mm cm, particularly an upper limit of D300 mm, more particularly an upper limit of D400 mm. For instance, the offset distance D can be 180 mmD220 mm. According to an example, the offset distance D may be 201 mm.
[0039] As exemplarily shown in
[0040] With exemplary reference to
[0041] With exemplary reference to
[0042] According to some embodiments which can be combined with other embodiments described herein, at least one holding element can be configured to be connected to a mask carrier with magnetic forces. For example, the at least one holding element may include an electromagnet, which can be switched on for engaging the holding element to a mask carrier.
[0043] Further, with exemplary reference to
[0044] According to some embodiments, the alignment system 140 may include a substrate holding arrangement which may include one or more substrate holding elements. For instance, the one or more substrate holding elements can be configured to be connected to a substrate carrier with magnetic forces. For example, the one or more substrate holding elements may include an electromagnet, which can be switched on for engaging the holding element to a substrate carrier.
[0045] In some implementations, the alignment system includes one or more piezoelectric actuators for positioning the substrate carrier and the mask carrier with respect to each other. As an example, the two or more alignment actuators can be piezoelectric actuators for positioning the substrate carrier and the mask carrier with respect to each other. However, the present disclosure is not limited to piezoelectric actuators. As an example, the two or more alignment actuators can be electric or pneumatic actuators. The two or more alignment actuators can for example be linear alignment actuators. In some implementations, the two or more alignment actuators can include at least one actuator selected from the group consisting of: a stepper actuator, a brushless actuator, a DC (direct current) actuator, a voice coil actuator, a piezoelectric actuator, and any combination thereof.
[0046] Accordingly, it is to be understood that the mask carrier may be moved into a predetermined mask position on the second track, thereafter a holding arrangement as described herein may move forward to hold the mask carrier. After the mask carrier is positioned, the substrate carrier may be moved into a predetermined substrate position. Then the substrate carrier can be aligned, e.g. by an alignment system as described herein, with respect to the mask carrier.
[0047] With exemplary reference to
[0048] According to embodiments which can be combined with any other embodiments described herein, the first distance D1 may be between a lower limit of D10.7 m, particularly a lower limit of D10.9 m, more particularly a lower limit of D11.1 m and an upper limit of D1.5 m, particularly an upper limit of D2.0 m, more particularly an upper limit of D3.0 m, for instance an upper limit of D4.0 m or more.
[0049] According to embodiments which can be combined with any other embodiments described herein, the first distance D2 may be between a lower limit of D20.85 m, particularly a lower limit of D21.2 m, more particularly a lower limit of D21.5 m and an upper limit of D22.2 m, particularly an upper limit of D23.3 m, more particularly an upper limit of D24.4 m or more.
[0050] Accordingly, as exemplarily shown in
[0051]
[0052] With exemplary reference to
[0053] It is to be understood that the features as described in connection with the first magnetic guiding structure of the first track 110 as well as in connection with the first magnetic drive structure of the first track 110 can also be applied to the second guiding structure 121 and the second drive structure 122, respectively. Accordingly, with exemplary reference to
[0054] With exemplary reference to
[0055] Typically, an active magnetic element of the plurality of active magnetic elements 113 is configured for providing magnetic force interacting with the first passive magnetic element 151 of the substrate carrier 150. In particular, the first passive magnetic element 151 and the plurality of active magnetic elements 113 of the first guiding structure 111 can be configured for providing a magnetic levitation force for levitating the substrate carrier 150, as exemplarily indicated by the vertical arrows pointing towards the first guiding structure 111 in
[0056] Further, as exemplarily shown in
[0057] Typically, the further active magnetic elements 114 can be configured to interact with the second passive magnetic element 152 for providing a force along the substrate transport direction. For example, the second passive magnetic element 152 can include a plurality of permanent magnets, which are arranged with an alternating polarity. The resulting magnetic fields of the second passive magnetic element 152 can interact with the plurality of further active magnetic elements 114 to move the substrate carrier 150 while being levitated.
[0058] In order to levitate the substrate carrier 150 with the plurality of active magnetic elements 113 and/or to move the substrate carrier 150 with the plurality of further active magnetic elements 114, the active magnetic elements can be controlled to provide adjustable magnetic fields. The adjustable magnetic field may be a static or a dynamic magnetic field. According to embodiments, which can be combined with other embodiments described herein, an active magnetic element as described herein can be configured for generating a magnetic field for providing a magnetic levitation force, for instance extending along a vertical direction, e.g. the y-direction shown in
[0059] As shown in
[0060] As exemplarily shown in
[0061] Further, one or more further active magnetic elements 114 can be controlled by the substrate carrier controller 155. The further active magnetic elements 114 interact with the second passive magnetic element 152. For example, the second passive magnetic element 152 may include a set of alternating permanent magnets, to generate a driving force as exemplarily indicated by the horizontal arrow in
[0062] In the second position, as exemplarily shown in
[0063] Accordingly, it is to be understood that the substrate carrier controller 155 may be configured for controlling the active magnetic elements 113 for translationally aligning the substrate carrier in a vertical direction, e.g. with a mask carrier as described herein. Further, by controlling the active magnetic elements, the substrate carrier 150 may be positioned into a target vertical position. The substrate carrier 150 may be maintained in the target vertical position under the control of the substrate carrier controller 155. Further, the substrate carrier controller 155 can be configured for controlling the active magnetic elements 113 for angularly aligning the substrate carrier 150 with respect to a first rotation axis, e.g. a rotational axis perpendicular to the substrate surface, e.g. a rotational axis extending in a z-direction as exemplarily indicated in
[0064] According to embodiments, which can be combined with other embodiments described herein, the positioning arrangement can be configured for providing an alignment, particularly a contactless alignment, of the substrate carrier with respect to the mask carrier, e.g. in a vertical direction, with an alignment range from 0.1 mm to 3 mm. Further, an alignment precision, particularly a contactless alignment precision, in the vertical direction can be 50 m or below, for example 1 m to 10 m, such as 5 m. Further, a rotational alignment precision, particularly a contactless rotational alignment precision, of the positioning arrangement can be 3 or below.
[0065] As described above, the one or more further active magnetic elements 114 of the first drive structure 112 can be configured for providing a driving force along the extension of the first track, e.g. the x-direction. Accordingly, it is to be understood that the substrate carrier controller 155 can be configured to control the one or more further active magnetic elements 114 to provide for an alignment in a transport direction, for example the x-direction in
[0066] Accordingly, embodiments of the positioning arrangement as described herein provide for levitated substrate carrier movement which allows for a high precision in substrate positioning in a transport direction and/or a vertical direction. Further, embodiments of the positioning arrangement as described herein provide for improved alignment of a substrate carrier relative to a mask carrier, e.g. by horizontal and/or vertical and/or rotational alignment.
[0067]
[0068] With exemplary reference to
[0069] Further, it is to be understood that the features with respect to the configuration of the first track 110 and the second track 120 of the positioning arrangement as described herein, e.g. with reference to
[0070] Accordingly, beneficially an improved transportation system for transporting a substrate carrier and a mask carrier is provided. In particular, by providing a transportation system which is configured for contactless transportation of a substrate carrier and the mask carrier, beneficially a generation of particles, e.g. generated due to a mechanical contact between the carriers and the transportation tracks, can be avoided during transportation of the carriers. Accordingly, embodiments described herein provide for an improved purity and uniformity of the layers deposited on the substrate, in particular since a particle generation is minimized when using the contactless transportation. Further, by providing a transportation system wherein a first track for a substrate carrier and a second track for a mask carrier are configured to correspond to a first track and the second track of the positioning arrangement as described herein, the transportation system can be used in combination with positioning arrangement, particularly without any intermediate adaption arrangement.
[0071] According to embodiments which can be combined with any other embodiments described herein, the first track 110 of the transportation system 200 includes a first guiding structure 111 and a first drive structure 112 which are spaced apart by a first distance D1, as exemplarily shown in
[0072] According to embodiments which can be combined with any other embodiments described herein, the first guiding structure 111 of the first track 110 of the transportation system 200 can be a first magnetic guiding structure which may be configured as the first magnetic guiding structure of the positioning arrangement 100, as exemplarily described with reference to
[0073] Accordingly, it is to be understood that the second guiding structure 121 of the transportation system 200 can be a second magnetic guiding structure which may be configured as the second magnetic guiding structure of the positioning arrangement 100, as exemplarily described with reference to
[0074] With exemplary reference to
[0075] In the present disclosure, a vacuum processing chamberis to be understood as a vacuum chamber or a vacuum deposition chamber. The term vacuum, as used herein, can be understood in the sense of a technical vacuum having a vacuum pressure of less than, for example, 10 mbar. Typically, the pressure in a vacuum chamber as described herein may be between 10.sup.5 mbar and about 10.sup.8 mbar, more typically between 10.sup.5 mbar and 10.sup.7 mbar, and even more typically between about 10.sup.6 mbar and about 10.sup.7 mbar. According to some embodiments, the pressure in the vacuum chamber may be considered to be either the partial pressure of the evaporated material within the vacuum chamber or the total pressure (which may approximately be the same when only the evaporated material is present as a component to be deposited in the vacuum chamber). In some embodiments, the total pressure in the vacuum chamber may range from about 104 mbar to about 10.sup.7 mbar, especially in the case that a second component besides the evaporated material is present in the vacuum chamber (such as a gas or the like).
[0076] With exemplary reference to
[0077] Typically, coating of the substrates may include masking the substrates by respective masks, e.g. by an edge exclusion mask or by a shadow mask. According to typical embodiments, the masks, e.g. a first mask 161A corresponding to a first substrate 101A and a second mask 161B corresponding to a second substrate 101B, are provided in a mask carrier 116 to hold the mask in a predetermined position, as exemplarily shown in
[0078] According to some embodiments, which can be combined with other embodiments described herein, the substrate 101 is typically supported by a substrate carrier 150, which can be connected to an alignment system 350, e.g. by connecting elements 324. The alignment system 350 can be configured for adjusting the position of the substrate 101 with respect to the mask 161. Accordingly, it is to be understood that the substrate can be moved relative to the mask in order to provide for a proper alignment between the substrate and the mask during deposition of the organic material. According to a further embodiment, which can be combined with other embodiments described herein, alternatively or additionally the mask carrier holding the mask can be connected to the alignment system 350. Accordingly, either the mask can be positioned relative to the substrate 101 or the mask 330 and the substrate 101 can both be positioned relative to each other. Accordingly, an alignment system as described herein allows for a proper alignment of the masking during the deposition process, which is beneficial for high quality or OLED display manufacturing.
[0079] Examples of an alignment of a mask and a substrate relative to each other include alignment units, which allow for a relative alignment in at least two directions defining a plane, which is essentially parallel to the plane of the substrate and the plane of the mask. For example, an alignment can at least be conducted in an x-direction and a y-direction, i.e. two Cartesian directions defining the above-described parallel plane. Typically, the mask and the substrate can be essentially parallel to each other. Specifically, the alignment can further be conducted in a direction essentially perpendicular to the plane of the substrate and the plane of the mask. Thus, an alignment unit is configured at least for an X-Y-alignment, and specifically for an X-Y-Z-alignment of the mask and the substrate relative to each other. One specific example, which can be combined with other embodiments described herein, is to align the substrate in x-direction, y-direction and z-direction to a mask, which can be held stationary in the vacuum processing chamber.
[0080] With exemplary reference to
[0081] With exemplary reference to the flow chart shown in
[0082] With exemplary reference to the flow chart shown in
[0083] In particular, embodiments of the method 400 for transporting a substrate carrier 150 and a mask carrier 160 through a processing system may include using a transportation system 200 as described herein. Accordingly, an improved method for transporting a substrate carrier 150 and a mask carrier 160 through a processing system, e.g. a vacuum processing system 300 as described herein, is provided.
[0084] While the foregoing is directed to embodiments of the disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.
[0085] In particular, this written description uses examples to disclose the disclosure, including the best mode, and also to enable any person skilled in the art to practice the described subject-matter, including making and using any devices or systems and performing any incorporated methods. While various specific embodiments have been disclosed in the foregoing, mutually non-exclusive features of the embodiments described above may be combined with each other. The patentable scope is defined by the claims, and other examples are intended to be within the scope of the claims if the claims have structural elements that do not differ from the literal language of the claims, or if the claims include equivalent structural elements with insubstantial differences from the literal language of the claims.