FIELD OF INVENTION
[0002] The invention disclosed herein relates, in general, to semiconductor devices. More specifically, the present invention relates to a circular photovoltaic device and a method of manufacturing thereof.
BACKGROUND
[0003] Thin-film solar cells have lower photoelectric conversion efficiency compared to mono-crystalline silicon solar cells. Typically doctor blade, PECVD, PVD or screen printing processes are used for application of films over large area. These results in poor uniformity of the films, thereby negatively impacting photoelectric conversion efficiency.
[0004] Moreover, current shapes of cells permit low area efficiency. For example, currently
the best area efficiency is about 70% in case of square shaped thin film solar cells. This low area
efficiency leads to decreased availability of photoelectric material for facilitating photoelectric
conversion. Modification in shapes is further constrained by availability of processes for
application of films.
[0005] Additionally, manufacturing the thin film solar cell involves scribing. This process of requires extensive arrangements to be made to enable movement of thin film solar cells in different direction in order to form scribing patterns. This results in an increased production cost. Further, formation of the scribing patterns require intricate movement of the thin film solar cells leading to an inherently slow scribing speed, thereby resulting in increased production time.
[0006] Accordingly, in light of the above discussion, there is a need for a photovoltaic device that has a high efficiency, a low production cost, and eliminates one or more drawbacks of the prior art.
BRIEF DESCRIPTION OF FIGURES
[0007] The features of the present invention, which are believed to be novel, are set forth with particularity in the appended claims. The invention may best be understood by reference to the following description, taken in conjunction with the accompanying drawings. These drawings and the associated description are provided to illustrate some embodiments of the invention, and not to limit the scope of the invention.
[0008] FIG. 1 illustrates a top view of an exemplary organic photovoltaic device (OPV), in accordance with an embodiment of the present invention;
[0009] FIGs. 2a and 2b illustrate an exemplary OPV and a perspective cut-out view of the exemplary OPV, respectively, in accordance with an embodiment of the present invention;
[0010] FIG. 3 illustrates a cross-sectional view of the OPV of FIG.l along an axis O-X, in accordance with an embodiment of the present invention;
[0011] FIG, 4 illustrates a view of an exemplary scribing system used for scribing an OPV, in accordance with an embodiment of the present invention;
[0012] FIGs. 5a and 5b illustrate a perspective cross-sectional view of an exemplary OPV before and after scribing, respectively, in accordance with an embodiment of the present invention;
[0013] FIG. 6 is a flow chart describing an exemplary process of manufacturing an exemplary OPV, in accordance with an embodiment of the present invention; and
[0014] FIG. 7 illustrates a top view of another exemplary organic photovoltaic device (OPV), in accordance with an embodiment of the present invention.
[0015] Those with ordinary skill in the art will appreciate that the elements in the figures are illustrated for simplicity and clarity and are not necessarily drawn to scale. For example, the
dimensions of some of the elements in the figures may be exaggerated, relative to other elements, in order to improve the understanding of the present invention.
[0016] There may be additional structures described in the foregoing application that are not depicted on one of the described drawings. In the event such a structure is described, but not depicted in a drawing, the absence of such a drawing should not be considered as an omission of such design from the specification.
SUMMARY
[0017] The present invention provides a thin film solar cell. The thin film solar cell includes a circular substrate having a substantially flat surface. Further, the thin film solar cell includes a plurality of concentric regions that are mutually separated by one or more concentric separating regions. The thin film solar cell also includes a plurality of unit solar cells that are electrically connected in series and are arranged over the plurality of concentric regions, such that each of the plurality of unit solar cells occupies a corresponding region of the plurality of concentric regions substantially completely.
[0018] In some embodiments, the present invention provides an organic photovoltaic device. The organic photovoltaic device includes a substrate having a substantially flat surface. The substrate is defined by a periphery that is substantially symmetrical about an axis perpendicular to the substantially flat surface. Further, the organic photovoltaic device also includes a plurality of photovoltaic units .arranged over the substrate, such that the plurality of photovoltaic units are substantially concentric to the axis and the plurality of photovoltaic units are electrically connected in series.
[0019] In some embodiments, the periphery of the organic photovoltaic device is selected from one of a circle, a rectangle and a regular polygon having four or more sides.
[0020] In some embodiments, the substantially flat surface comprises a plurality of regions substantially concentric with the axis and the plurality of regions are mutually separated by one or more substantially concentric separating regions.
[0021] In some embodiments, the plurality of photovoltaic units are disposed on the plurality of regions, such that each of the plurality of photovoltaic units occupies a corresponding region of the plurality of regions substantially completely.
[0022] In some embodiments, the plurality of photovoltaic units are formed by one of a mechanical scribing and a laser scribing process.
DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
[0023] Before describing the present invention in detail, it should be observed that the present invention utilizes a combination of method steps and apparatus components related to a thin film photovoltaic device. Accordingly the apparatus components and the method steps have been represented where appropriate by conventional symbols in the drawings, showing only specific details that are pertinent for an understanding of the present invention so as not to obscure the disclosure with details that will be readily apparent to those with ordinary skill in the art having the benefit of the description herein.
[0024] While the specification concludes with the claims defining the features of the invention that are regarded as novel, it is believed that the invention will be better understood from a consideration of the following description in conjunction with the drawings, in which like reference numerals are carried forward.
[0025] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present
invention in virtually any appropriately detailed structure. Further, the terms and phrases used herein are not intended to be limiting but rather to provide an understandable description of the invention.
[0026] The terms "a" or "an", as used herein, are defined as one or more than one. The term "another", as used herein, is defined as at least a second or more. The terms "including" and/or "having" as used herein, are defined as comprising (i.e. open transition). The'term "coupled" or "operatively coupled" as used herein, is defined as connected, although not necessarily directly, and not necessarily mechanically.
[0027] Referring now to the drawings, there is shown in FIG. 1 a perspective top view of an exemplary Organic Photovoltaic Device (OPV) 100, in accordance with an embodiment of the present invention. A photovoltaic device converts incident solar light into electrical energy. The photovoltaic device includes one or more semi-conductive photoactive layers that are capable of generating excitons, i.e., bound electron-hole pairs, on receiving solar energy in form of light. These electron-hole pairs dissociate into charge carrying electrons and holes, thereby generating electricity. The generated electrons are drawn as current in an external circuit connected to the photovoltaic device. Examples of the OPV device 100 include, but are not limited to, a thin film solar cell, an organic solar cell, an hybrid solar cell, a tandem solar cell, a quantum dot solar cells, a nano-structured solar cell and the like.
[0028] In the figure, the OPV device 100 is shown to include a plurality of photovoltaic units 102,104 and 106. The photovoltaic units 102,104 and 106 are arranged over a substrate having a substantially flat surface (not shown). In the figure the flat surface of the substrate is in a plane defined by two axes O-X and O-Y. Further, the flat surface also includes a plurality of regions over which the plurality of photovoltaic units 102,104 and 106 are disposed. Further, the OPV device 100 includes one or more separating regions 110 positioned such that they mutually separate the plurality of regions on which the plurality of photovoltaic units 102,104 and 106 are disposed. Also, the photovoltaic units 102,104 and 106 are so disposed on the plurality of regions that they substantially completely cover the plurality of regions. Further, the OPV device 100 includes a vacant inner region 108 which is used for encapsulation of the OPV device 100.
Similarly, the OPV device 100 also includes a vacant outer region 112 for encapsulating the OPV device 100.
[0029] Further, the substrate of the OPV device 100 is shown to have a periphery that is circular in shape. However, in accordance with the present invention, the periphery can be of any shape that is substantially symmetrical about an axis perpendicular to the substrate of the OPV device 100. For example, in FIG, 1 the periphery of substrate of the OPV device 100 is circular that is substantially symmetrical about an axis, passing through a point O at centre of the OPV device 100 and perpendicular to the plane defined by the two axes O-X and O-Y. Other examples of such periphery include, but are not limited to, a rectangle and a regular polygon having four or more sides. For example, in an embodiment of the present invention, the substrate of the OPV device 100 can have a substantially hexagonal periphery, without departing from the scope of the present invention.
[0030] Moving on, the plurality of regions on the substrate over which the plurality of photovoltaic units 102,104 and 106 are disposed, and the one or more separating regions 110 are arranged such that they are substantially concentric with the axis passing through the point O at centre of the OPV device 100. Further, periphery of the plurality of regions and the one or more separating regions 110 is similar to that of the substrate of the OPV device 100. Further, the photovoltaic units 102,104 and 106 are also shown to have a periphery that is circular in shape and are substantially concentric with the axis passing through the point O at centre of the OPV device 100.
[0031] Furthermore, in another embodiment of the present invention, the periphery of the substrate of the OPV device 100 and the periphery of the plurality of photovoltaic units disposed over the plurality of regions can be different. For example, the periphery of the OPV device 100 can be hexagonal, whereas the periphery of the plurality of regions and the plurality of photovoltaic units forming the OPV device 100 can be circular in shape as shown in FIG. 7.
[0032] While in FIG.l, the OPV device 100 is illustrated with three photovoltaic units, it should be appreciated that the OPV device 100 can include any number of photovoltaic units without departing from the scope of the present invention.
[0033] The number of photovoltaic units in the OPV device 100 is determined such that a surface area of each of the plurality of photovoltaic units is almost equal and a TCO resistance value of the plurality of photovoltaic units decrease in a direction of a current flow. An exemplary scenario illustrating a calculation of a number of the plurality of photovoltaic units in the OPV device 100 has been depicted in FIGs. 2a and 2b. FIG. 2b illustrates a cut out view of an exemplary OPV having a circular periphery as shown in FIG. 2a. The plurality of photovoltaic units in the OPV device 100 has been illustrated in the figure as a plurality of rectangular strips for easier understanding of area and resistance calculation.
[0034] Moving on, an example of calculation of a number of the plurality of photovoltaic units is shown in reference to FIGs. 2a and 2b. For example, a current across the plurality of photoactive units is governed by corresponding area units. Hence, according to the present invention, all the photovoltaic units are preferably required to have a same device area. This is ensured by decreasing effective radial width of each of the plurality of photovoltaic units as their effective length increases. For example, an effective length 'f' of the photovoltaic unit 102 is greater than an effective length 'e' of the photovoltaic unit 104, that is in turn greater than an effective length 'd' of the photovoltaic unit 106. In order to equate the area of individual photovoltaic units, an effective radial width 'c' of the photovoltaic unit 102 is less than an effective thickness 'b' of the photovoltaic unit 104, which is in turn less than an effective thickness 'a' of the photovoltaic unit 106.
[0035] For example, if a current requirement is Y mA and a current density of the photovoltaic device is X mA/cm2, then an area of each photovoltaic unit is Y/X cm2. Now, if a total available photovoltaic area is Z cm2 then the number of photovoltaic units required will be Z*X/Y. So the scribing has to be performed at (Z*X/Y -1) places. An advantage provided by the design of this invention is that an area efficiency provided is higher than those provided by those
in prior art. Usually an area efficiency of >80% is provided by the present invention. Note that in such calculations, total available photovoltaic active area excludes an interconnection loss area.
[0036] Further, the number of photovoltaic units can also be increased or decreased depending upon a resistance offered by the photovoltaic device area. Further, the design also provide another basic advantage that during series connection of the photovoltaic units, the photovoltaic unit connected to the next photovoltaic unit always has a lower series resistance due to a different dimension (higher to length),
[0037] Structure of the OPV device 100 has been described in greater detail in conjunction with FIG. 3, which itlustrates a cross-sectional view of the OPV device 100 along the axis OX. There is illustrated in FIG. 3 a stack of layers forming the OPV device 100, Further, as can be seen, the cross-section of the OPV device 100 is also shown to include the cross-section of the photovoltaic units 102,104 and 106 that are separated from each other but etectrically connected in series. For the purpose of easy understanding of the present invention, the stack of layers forming the OPV device 100 ■will be described first followed by description of interconnection structure.
[0038] The stack of layers is shown to include a substrate 302,. a first electrical contact 304, one or more semiconductor layers 306, a second electrical contact 308 and a cover substrate or cover layer 310 thai can be applied on the second electrical contact 308 and encapsulates the first electrical contact 304, the one or more semiconductor layers 306, the second electrical contact 308 between itself and the substrate 302. The cover substrate or cover layer 310 encapsulates all elements of the OPV device between vacant inner region 108 and cuter vacant region 109.
[0039] For the purpose of the description, the OPV device 100 has been shown to include only those layers that are pertinent to the description of the invention. However, it should be understood that the invention is not limited to the layers listed above. In some cases, the OPV device 100 may include additional layers to enhance efficiency or to improve reliability, without deviating from the scope of the invention,
[0040] The substrate 302 has a substantially flat surface on which other subsequent layers can be deposited. Further, the substrate 302 provides strength to the OPV device 100. During real life applications, the OPV device 100 is placed in a way that the substrate 302 is facing the sun when the OPV device 100 is in use, and the substrate 302 acts as a surface that receives and transmits incident solar light through the OPV device 100. Examples of material that can be used as the substrate 302 include, but are not limited to, glass, flexible glass, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), Polycarbonate (PC) and other transparent or translucent material.
[0041] The first electrical contact 304 and the second electrical contact 308 are used to apply a potential difference" across the one or more semiconductor layers 306. The first electrical contact 304 can be implemented with, for example, a transparent conductive oxide (TCO). TCOs are doped metal oxides, examples of TCOs include, but are not limited to, Aluminum-doped Zinc Oxide (AZO), Indium Zinc Oxide (IZO), Boron doped Zinc Oxide (BZO), Gallium doped Zinc Oxide (GZO), Fluorine doped Tin Oxide (FTO) and Indium doped Tin Oxide (ITO). Further, the second electrical contact 308 can be implemented with metals with appropriate work function to make injection of charge carriers, for example, calcium, aluminum, gold, and silver etc.
[0042] Next set of layers in the stack of the OPV device 100 are the one or more semiconductor layer 306. For the purpose of this description, three semiconductor layers are shown in FIG.3. The three semiconductor layers can include a n-type semiconductor layer, a bulk heterojunction layer consisting of p-type and n-type organic/inorganic materials, and a p-type semiconductor layer. However, it will be readily apparent to those skilled in the art that the OPV device 100 can include or exclude one or more semiconductor or organic layers without deviating from the scope of the invention.
[0043] Generally, the one or more semiconductor layers 306 are deposited using spin coating, sol-gel, screen printing, slot-die coater, inkjet, spray, thermal evaporation, on the first electrical contact 304. For the purpose of this description, example of the layer of n-type semiconductor includes, but is not limited to, ZnO. Examples of the bulk heterojunction layer of
p-type & n-type semiconductor, include but are not limited to, a polymer and fullerene. Usually, the semiconductor layers are deposited in a CTL-BHJ-CTL order, i.e. charge transport layer -bulk heterojunction layer - charge transport layer.
[0044] Other examples of material for the one or more semiconductor layers 306 can be any organic electroluminescent material such as a light-emitting polymer, evaporated small molecule materials, light-emitting dendrimers or molecularly doped polymers.
[0045] In an exemplary embodiment, a light trapping layer (not shown in the Figures) may also be deposited on the substrate 302 before depositing the first electrical contact 304. The light trapping layer is provided to increase an optical path of the light transmitted in to the OPV 100 from the substrate 302. For example the light entering the substrate 302 from an ambient medium on reaching the light trapping layer, is allowed to pass through to the one or more semiconductor layers 306 and prevented from being reflected back into the ambient medium from where the light enters. The light trapping layer also enhances the absorption in visible regions of spectrum.
[0046] Moving on to the interconnection structure of the OPV device 100, all the layers of the photovoltaic units 102,104 and 106 above the substrate 302 are shown to be isolated from one another. However, the photovoltaic units 102,104 and 106 are connected to each other such that the second electrical contact 308 of the photovoltaic unit 106 is connected to the first electrical contact 304 of the photovoltaic unit 104 and the second electrical contact 308 of the photovoltaic unit 104 is connected to the first electrical contact 304 of the photovoltaic unit 102. This interconnection of the photovoltaic units is ensured by a scribing process, which will be described in greater detail in conjunction with FIGs. 4,5 and 6.
[0047] Moving on to FIG. 4, there is illustrated in the figure a view of an exemplary scribing system 400 used for scribing various layers of an OPV, for example the OPV device 100, in accordance with an embodiment of the present invention. The scribing system 400 is shown to include a scribe handler 402, an electro-mechanical arm 404, a needle 406 and a needle head 408. For the purpose of the description, the scribing system 400 has been shown to include elements that are pertinent to the description of the invention. However, it should be understood
that the invention is not limited to the elements listed above. In some cases, the scribing system 400 may include greater or fewer numbers of elements than those disclosed to enhance efficiency or to improve reliability, without deviating from the scope of the invention.
[0048] The scribe handler 402 moves in predefined direction for scribing the various layers of the OPV device 100. In an embodiment, the scribe handler 402 can have one needle 406 for generating a scribing or in another embodiment, the scribe handler 402 may have two or more needles 406 for generating two or more scribing, without deviating from the scope of the invention.
[0049] The electro-mechanical arm 404 moves in to the different radius for scribing the various layers of the OPV device 100. In an embodiment, the needle head 408 can be in touch of a solvent to be used for scribing the various layers of the OPV device 100. A material of the needle head 408 would have hardness higher than the various layers of the OPV device to scribe.
[0050] According to the invention, the needle head can be positioned at a point over the OPV 100 where scribing needs to be performed. The OPV device 100 is meanwhile, positioned on a horizontal and a flat surface, for example a table or a spin chuck. In an embodiment, the table can be rotated around a vertical axis as shown by arrows in the figure. This reduces time needed to form scribing patterns, resulting in a decreased scribing time. Usually in the scribing process, a spin-rpm depends upon hardness of the various layers to be scribed as well as a pressure applied by the scribe handler 402. In an embodiment, the spin rpm can be in a range between 50 to 3000rpm. In another embodiment, the table can also be moved in two or more horizontal directions.
[0051] In another embodiment, instead of using a needle for scribing any other suitable LASER source may be integrated in the scribing system 400 by replacing the needle 406 and needle head 408 with a LASER HEAD of a suitable wavelength. The selection of wavelength depends upon the OPV layer to be scribed. Also, other modes of scribing like chemical cleaning may be used, without deviating from the scope of the invention.
[0052] According to the invention, the scribing system 400 can be used to scribe any layer of the OPV 100. The needle head 408 of the scribing system 400 cuts through the layers of the OPV 100 completely to form gaps between the plurality of photovoltaic units to electrically insulate adjacent photovoltaic units. An exemplary structure of an OPV device before and after scribing has been illustrated in FIG. 5a and 5b. The method of manufacturing the OPV device 100 including scribing the various layers of the OPV device 100 has been explained in greater detail in conjunction with FIG. 6.
[0053] FIG. 6 illustrates a flow chart describing an exemplary process 600 of manufacturing an OPV, for example OPV device 100, in accordance with an embodiment of the present invention. To describe the method 600, reference will be made to FIGs. 1,2,3, 4, and 5, although it is understood that the method 600 can be implemented in any other suitable environment. Moreover, the invention is not limited to the order in which the steps are listed in the method 600. Further, it will also be apparent to those ordinarily skilled in the art that the method 600 may include one or more additional steps for further enhancement of the effectiveness of the method 600, however, are not essential to the method 600, in accordance with the present invention.
[0054] Further, for the purpose of description, the method 600 has been explained in reference to mechanical scribing, however, it will be readily apparent to those ordinarily skilled in the art that the present invention can be implemented using other scribing methods as well, without deviating from the scope of the invention.
[0055] The method 600 is initiated at step 602. Thereafter, at step 604, a substrate, for example the substrate 302, is provided. Following this at step 606, a first electrical contact, for example the first electrical contact 304, is deposited over the substrate 302. The first electrical contact 304 may be deposited by using various methods, such as sputtering, sol-gel, thermal evaporation, electroforming, all kinds of CVD, and evaporation. Preferably, the first electrical contact 304 is deposited using sputtering.
[0056] Thereafter, at step 608, a first scribe is performed to divide the first electrical contact 304 on the substrate 302, into isolated stripes. This scribing is repeated at different points depending upon the number of the plurality of photovoltaic units needed and once the scribing has been performed at a required radius, the needle head can be moved and positioned over a next point where scribing needs to be performed. For example, as shown in FIG.5a, in case three photovoltaic units are needed, scribing is performed at points LI and L2.
[0057] Following this, at step 610, one or more semiconductor layers, for example the one or more semiconductor layers 306 are deposited on the first electrical contact 304. The one or more semiconductor layers 306 are deposited by using various methods, such doctored blade, spray coating, screen printing, sputtering, slot-die coating, spin-coating, sol-gel, and evaporation. Preferably, the one or more semiconductor layers 306 are deposited using spin coating.
[0058] Thereafter, at step 612, a second scribe is performed to divide one or more semiconductor layers 306, such that it provides an interconnect path using which the second electrical contact 308 contacts the first electrical contact 304. This scribing is repeated at different points depending upon the number of the plurality of photovoltaic units needed.
[0059] Thereafter, at step 614, a second electrical contact, for example, the second electrical contact 308 is deposited on the one or more semiconductor layers 306. The second electrical contact 308 may be deposited by using various methods, such as doctored blade, spray coating, screen printing, slot-die coating, sputtering, and evaporation. Preferably, the second electrical contact 306 is deposited using evaporation.
[0060] Thereafter, at step 616, a third scribe is performed to cut the second electrical contact 308 filling the interconnect path formed during the step 612, thereby interconnecting the second electrical 308 with the first electrical contact 304 and also isolating the plurality of the photovoltaic units. This scribing is repeated at different points depending upon the number of the plurality of photovoltaic units needed. This completes a series-interconnected structure of the OPV 100. In an embodiment, a cover layer or cover substrate can also be deposited on the second electrical contact 308 after the step 616. A material for the cover layer could be in-
organic or organic or combination of both. The cover substrate can also be used to encapsulate the device after the step 616. The cover substrate will encapsulate the first electrical contact 304, the one or more semiconductor layers 306, and the second electrical contact 308 between itself and the substrate 302. Thereafter the method 600 is terminated at step 618.
[0061] Usually, in manufacturing of thin-film photovoltaic devices, a three-scribe process, like the one described above is used. However, it should be appreciated that other variations of this process are possible and can be used without deviating from the scope of the invention. Furthermore, different wavelengths of laser may be used during the three scribing steps in order to get a suitable wavelength for each of the steps.
[0062] Various embodiments, as described above, provide an organic photovoltaic device and a method of manufacturing the organic photovoltaic device which has several advantages. One of the several advantages is higher area utilization of the substrate being used for organic photovoltaic device, this results in an increase in efficiency of the organic photovoltaic device. Another advantage is that the method used for manufacturing the organic photovoltaic device of the present invention can be very easily integrated into an inline process. Additionally, given the shape of the organic photovoltaic device of the present invention, the organic photovoltaic device can be easily manufactured using a system for manufacturing an optical disc. Further, use of a plastic / flexible substrate in such a design, makes the organic photovoltaic device look aesthetic in nature.
[0063] While the invention has been disclosed in connection with the preferred embodiments shown and described in detail, various modifications and improvements thereon will become readily apparent to those ordinarily skilled in the art. Accordingly, the spirit and scope of the present invention is not to be limited by the foregoing examples, but is to be understood in the broadest sense allowable by law.
[0064] All documents referenced herein are hereby incorporated by reference.

CLAIMS
What is claimed is:
1. An organic photovoltaic device comprising:
a substrate having a substantially flat surface, said substrate being defined by a periphery, said periphery being substantially symmetrical about an axis perpendicular to said substantially flat surface;
a plurality of photovoltaic units over said substrate, wherein said plurality of photovoltaic units are substantially concentric to said axis, said plurality of photovoltaic units being electrically connected in series.
2. The organic photovoltaic device of Claim 1, wherein said periphery is selected from one
of a circle and a regular polygon having four or more sides.
3. The organic photovoltaic device of Claim 1, wherein said substantially flat surface
comprises a plurality of regions substantially concentric with said axis, said plurality of regions being mutually separated by one or more substantially concentric separating regions, wherein said plurality of regions correspond to said plurality of photovoltaic units.
4. The organic photovoltaic device of Claim 3, wherein said plurality of photovoltaic units
are disposed on said plurality of regions, further wherein each of said plurality of photovoltaic units occupies a corresponding region of said plurality of regions substantially completely.
5. The organic photovoltaic device of Claim 1, wherein said plurality of photovoltaic units
are formed by one of a mechanical scribing and a laser scribing process.