Cutting tape and related methods

Abstract

A dicing tape is described, which comprises: a base layer; a first outer layer disposed on top of the base layer and different from the base layer; and optionally a pressure sensitive adhesive layer; wherein the base layer and the first outer layer comprise a polyolefin-based copolymer; and wherein the first outer layer comprises an organic or inorganic filler in an amount of 3 to 25 wt.-%, based on the total weight of the respective layer. The dicing tape avoids the use of a PVC-based base material layer, exhibits excellent dicing properties (no whiskers, fuzz or chipping) during the dicing process, and at the same time ensures advantageous mechanical properties. In a further aspect, a dicing method is disclosed, which comprises the steps of mounting a semiconductor wafer onto the above-described dicing tape, dicing the semiconductor wafer, and separating the wafer from the dicing tape. Finally, a manufacturing method of the above-described dicing tape is described, wherein the dicing tape is produced by a multi-layer blown film extrusion process.

Description

Technical Field

[0001] This invention relates to dicing tapes for manufacturing semiconductor chips. Specifically, this invention relates to dicing tapes for dicing semiconductor wafers and for use in die bonding.

[0002] In some embodiments, the present invention relates to a method for manufacturing semiconductor chips or devices using diced tape. Background Technology

[0003] Dicing tapes (also known as dicing films, die-attach films, or tapes, as well as die-attach films and tapes) are widely used in the manufacturing processes of semiconductor chips and devices. For this purpose, semiconductor wafers are typically bonded and secured to the dicing tape, and then diced in this state to process the wafer into individual wafers of predetermined dimensions, which are later used as semiconductor chips. Subsequently, the individual semiconductor chips are picked up, thereby peeling the semiconductor chips off the dicing tape.

[0004] Before picking up, the wafer can be separated by expanding the underlying dicing film to widen the gap between the diced semiconductor components. During expansion, the dicing film must exhibit sufficient toughness to avoid breakage.

[0005] Typically, the dicing films used in this semiconductor manufacturing process usually consist of a substrate layer and a pressure-sensitive adhesive layer, and need to have good dicing properties and good mechanical relaxation properties.

[0006] For this purpose, cutting films using polyvinyl chloride (PVC) based substrate layers have been widely adopted because they exhibit excellent mechanical properties (e.g., tensile properties) and thermal stability.

[0007] However, given environmental concerns and the potential contamination of semiconductor components by chlorides and corrosion, there is an increasing need to avoid using PVC in cutting films.

[0008] Therefore, in recent years, cutting films using non-PVC resin-based materials such as polyolefin resins or ethylene methacrylate-acrylate resins have been developed (see, for example, JP H05211234 A and KR 101659057 B1). US 8 728910 B2 discloses a cutting film exhibiting less contamination and high expandability, wherein the cutting film comprises an olefin-based expandable substrate containing a 1-butene-α-olefin copolymer and a propylene-based elastomer composition containing a propylene-α-olefin copolymer.

[0009] However, although the adhesion level on semiconductor wafers can be appropriately adjusted, dicing films, including polyolefin-based substrate layers, are prone to linting, whisker formation (fibrous off-cuts), debris scattering during dicing, and chipping (see [link to documentation]). Figure 1A ) and blurred cut edges (see) Figure 1B Overall, this leads to poor-quality cutting and reduced productivity.

[0010] Furthermore, if lint adheres to the sides of the chip, it can severely reduce the reliability of the resulting semiconductor device. Additionally, if a single chip is picked up after being positioned using a CCD camera during the pick-up step, lint and lint can lead to identification errors.

[0011] Therefore, it remains desirable to provide cutting strips and cutting films that avoid the use of PVC-based substrate layers, exhibit excellent cutting properties during the cutting process (no fuzz, fraying, or chipping), and simultaneously ensure favorable mechanical properties during expansion.

[0012] Furthermore, it is desirable to provide cutting strips and cutting methods that do not require different settings or new machines in the cutting process compared to using PVC-based cutting strips.

[0013] However, JP H07 273173 A, US 2017 / 121569 A1 and WO 2018 / 123804 A1 disclose other examples of cutting tape, which do not adequately address the aforementioned issues. Summary of the Invention

[0014] This invention achieves this objective by utilizing the subject matter of the claims as defined herein. The advantages of the invention will be explained in further detail in the following sections, and other advantages will become apparent to those skilled in the art upon consideration of this disclosure.

[0015] Generally, in one aspect, the present invention provides a cutting strip comprising: a base layer; a first outer layer disposed on the base layer and different from the base layer; and optionally a pressure-sensitive adhesive layer; wherein the base layer and the first outer layer comprise a polyolefin copolymer; and wherein the first outer layer comprises an organic or inorganic filler in an amount of 3 to 25% by weight based on the total weight of the respective layers.

[0016] In other respects, the present invention relates to a dicing method comprising the steps of: mounting a semiconductor wafer onto the dicing tape, dicing the semiconductor wafer, and separating the wafer from the dicing tape.

[0017] In another aspect, the present invention relates to a method for manufacturing the above-mentioned cutting strip, wherein the cutting strip is produced by a multilayer blown film extrusion process. Attached Figure Description

[0018] Figure 1A These are exemplary microscopic images of cutting defects (whiskers, burrs, and chipped edges).

[0019] Figure 1B This is an exemplary microscopic image of a cutting defect (a blurred cutting line).

[0020] Figure 2A An exemplary cut strip configuration comprising a double-layer substrate is shown according to the present invention.

[0021] Figure 2B An exemplary cutting strip configuration having a three-layer substrate is shown according to the present invention.

[0022] Figure 3 An exemplary cutting method is shown.

[0023] Figure 4 Force-strain curves for measurements of the reference example and the exemplary cutting strip (machine direction) of the present invention are shown.

[0024] Figure 5 Force-strain curves for measurements of the reference example and the exemplary cutting strip (transversal direction) of the present invention are depicted. Detailed Implementation

[0025] To provide a more complete understanding of the invention, the following description of its illustrative embodiments is now introduced.

[0026] Cutting band

[0027] In a first embodiment, the invention generally relates to a cutting strip comprising: a base layer; a first outer layer disposed on the base layer and different from the base layer; and optionally a pressure-sensitive adhesive layer; wherein the base layer and the first outer layer comprise a polyolefin copolymer; and wherein the first outer layer comprises an organic or inorganic filler in an amount of 3 to 25% by weight based on the total weight of the respective layers.

[0028] It is worth noting that the cutting tape according to the invention exhibits a multilayered substrate layer having at least two sub-layers (i.e., a first outer layer and a base layer), on which a pressure-sensitive adhesive layer is typically disposed. As used herein, the term "substrate" or "substrate layer" defines the layer of the cutting tape excluding the pressure-sensitive adhesive (PSA) layer and the release liner disposed on the PSA layer.

[0029] Figure 2A A non-limiting example of the cutting strip (10) of the present invention is shown herein. In this document, a first outer layer (12) is applied to a base layer (11), and a pressure-sensitive adhesive layer (13) is disposed on the first outer layer (12) to form the cutting strip (10).

[0030] However, an additional layer can be placed inside the cutting strip.

[0031] exist Figure 2B In the particularly preferred embodiment shown, the membrane substrate (A) comprises, and particularly preferably comprises, three layers: a first outer layer (22), a base layer (21), and a second outer layer (24). The second outer layer (24) is different from the base layer (21) and is disposed on the side of the base layer (21) opposite to the first outer layer (22), and comprises a polyolefin copolymer. A pressure-sensitive adhesive layer (23) may be disposed on the first outer layer (22).

[0032] Typically, the cutting strip should not contain polyvinyl chloride (PVC) resin or other chlorinated resins.

[0033] It is worth noting that the polyolefin copolymers used for the first outer layer, the base layer, and the second outer layer (if present) can be the same or different. For ease of manufacturing and to ensure good compatibility between layers, it is preferable to use the same polyolefin copolymer for the first outer layer, the base layer, and the second outer layer (if present). Examples of polyolefin copolymers that can be independently selected for the first outer layer, the base layer, and the second outer layer (if present) will be described below.

[0034] In a preferred embodiment, the polyolefin copolymer is independently selected from polypropylene copolymers, particularly random copolymers of polypropylene formed from propylene, ethylene, and / or ethylene-α-olefins. More preferably, the polyolefin copolymer is independently selected from ethylene-propylene copolymers, and particularly preferably from multi-step polymerized ethylene-polypropylene copolymers.

[0035] Among polyolefin copolymers, heterogeneous reactor thermoplastic polyolefins (rTPOs) are particularly preferred from the viewpoint of tensile properties and thermal stability. These rTPOs (also known as "in-reactor thermoplastic polyolefin resins") are produced in a reactor via a multi-step process and exhibit characteristic morphologies different from those obtained by blending multiple polyolefins. Particularly preferred examples of rTPOs, in terms of the physical requirements during the cutting process, include a highly isotactic polypropylene matrix and a rubber component dispersed within the matrix, the rubber component comprising an ethylene / propylene copolymer.

[0036] Polyolefin copolymers preferably exhibit a melting temperature higher than 120°C, more preferably higher than 125°C, more preferably higher than 130°C, and particularly preferably higher than 135°C, as determined according to ISO 11357-3.

[0037] In a preferred embodiment, the polyolefin copolymer preferably exhibits a flexural modulus of 50 MPa to 500 MPa, more preferably 60 MPa to 300 MPa, further preferably 70 to 200 MPa, and particularly preferably 75 to 150 MPa as determined according to ISO 178.

[0038] Unless otherwise stated, all test methods relating to the physical and tensile test properties described herein shall be performed at room temperature (i.e., at about 23°C).

[0039] In another preferred embodiment, based on the total weight of the polyolefin copolymer, the ethylene content of the polyolefin copolymer is greater than 13% by weight, preferably greater than 14.5% by weight, more preferably greater than 15% by weight and less than 40% by weight, and particularly preferably greater than 17% by weight and less than 35% by weight. The ethylene content can be determined by methods known in the art, such as FT-IR spectroscopy, via quantitative methods. 13 The C-NMR spectroscopy method was appropriately used to determine this.

[0040] Although not limited thereto, polyolefin copolymers are preferred to have a melt flow rate (230°C / 2.16 kg) of less than 1.8 g / 10 min, preferably less than 1.6 g / 10 min, as determined according to ISO 11357-3.

[0041] The first outer layer and the second outer layer (if present) preferably independently contain a polyolefin copolymer selected from the above copolymers in an amount of 55-85% by weight, more preferably 60-80% by weight, and particularly preferably 65-75% by weight based on the total weight of the respective layers. On the other hand, the base layer preferably contains a polyolefin copolymer selected from the above copolymers in an amount of 80 to 100% by weight based on the total weight of the base layer, and more preferably 85 to 98% by weight based on the total weight of the base layer.

[0042] From the viewpoint of advantageous cutting properties and cutting quality, the first outer layer and the second outer layer (if present) independently contain organic or inorganic fillers in an amount of 3 to 25% by weight, preferably 5 to 22% by weight, and particularly preferably 10 to 20% by weight, based on the total weight of the respective layers. In embodiments, a filler amount in the range of 15 to 20% by weight is preferred.

[0043] In view of the above, it is preferable that the weight ratio of polyolefin copolymer to filler in the outer layer is lower than that in the base layer. Due to the relatively higher amount of filler in the outer layer and the lower proportion of polyolefin copolymer, the tendency for adhesion (i.e., the film adhering to itself when wound onto the roller) is reduced. This effect is also achieved when a relatively thin outer layer is used.

[0044] The filler can be either inorganic or organic. Examples of organic fillers include, but are not limited to, cellulose-based fillers (e.g., cellulose nanofibers or cellulose crystals). Examples of inorganic fillers include various inorganic powders composed of talc, silica, clay, gypsum, calcium carbonate, barium sulfate, alumina, beryllium oxide, ceramics (such as silicon carbide and silicon nitride), and metals or alloys (such as aluminum, copper, silver, gold, nickel, chromium, lead, tin, zinc, palladium, solder, carbon, etc.) that impart conductivity to the cutting film (if desired). Fillers can be used alone or in combination of two or more. Talc is particularly preferred as a filler material to improve control of the elastic modulus of the cutting strip and to reduce manufacturing costs.

[0045] In a preferred embodiment from the viewpoint of cutting quality, the organic or inorganic filler has an average particle size (d50) in the range of 1 to 10 μm, more preferably in the range of 2 to 5 μm, as determined by laser diffraction.

[0046] Preferably, the first outer layer, the base layer, and the second outer layer (if present) independently comprise low-density polyethylene (LDPE) and / or linear low-density polyethylene (LLDPE). While there are no particular limitations on their content, a total content of 2 to 25% by weight and a total content of 5 to 20% by weight based on the total weight of the respective layers are particularly preferred.

[0047] For the particularly improved physical properties of the cutting strip, low-density polyethylene (LDPE) and / or linear low-density polyethylene (LLDPE) exhibit a modulus of elasticity in the transverse direction (TD) in the range of 160 MPa to 600 MPa, preferably 180 MPa to 400 MPa, and a modulus of elasticity in the longitudinal direction (MD) in the range of 140 MPa to 550 MPa, preferably 170 MPa to 380 MPa, the modulus of elasticity being determined at 23°C according to ISO 527-3.

[0048] In addition to or as a substitute for LLDPE and / or LDPE, the first outer layer, the base layer, and the second outer layer (if present) may independently comprise a tensile modulus (according to ISO 527-3) of 50 to 200 MPa and a density of less than 0.915 g / cm³. 3 And preferably 0.885-0.915 g / cm³3 Any of very low density polyethylene (VLDPE), ultra-low density polyethylene (ULDPE), or ethylene-α-olefin elastomers can be used to fine-tune the mechanical properties of the cleaved membrane. Among these polymers, those polymerized via metallocene catalysis are preferred.

[0049] The first outer layer, the base layer, and the second outer layer (if present) may independently contain additional additives. For long-term durability, one or more additives selected from phenolic stabilizers (e.g., Irganox 1010), processing aids (e.g., anti-blocking agents), and antistatic additives may be added. Other additives, such as one or more selected from colorants, flame retardants, extenders, antioxidants, and surfactants, may be blended as needed.

[0050] The first outer layer, the base layer, and the second outer layer (if present) may independently preferably contain slip agents in an amount from 0.001% to 1.0% by weight based on the respective layer. Slip agents include, but are not limited to, unsaturated fatty acid amides (e.g., erucamide, oleamide, and linoleamide); saturated fatty acid amides (e.g., palmitamide, stearamide, arachidamide, behenamide, stearylstearamide, palmitylpalmitamide, and stearylarachidamide); and saturated ethylenediamides. ethylene-bis-amide (e.g., stearamide-ethyl-stearamide, stearamide-ethyl-palmitamide, and palmamide-ethyl-stearamide); unsaturated ethylene bis-amides (e.g., ethylene bis-stearamide, ethylene bis-oleamide, stearamide-mustamide, mustardamide-ethyl-mustamide, oleamide-ethyl-oleamide, mustardamide-ethyl-oleamide, oleamide-ethyl-mustamide, stearamide-ethyl-mustamide, mustardamide-ethyl-palmitamide, and palmamide-ethyl-oleamide); polyether polyols; diols; aliphatic hydrocarbon acids (e.g., adipic acid and sebacic acid); aromatic or aliphatic hydrocarbon esters (e.g., pentaerythritol monooleate); styrene-α-methylstyrene; fluoropolymers (e.g., polytetrafluoroethylene); silicon compounds (e.g., silicone oil); sodium alkyl sulfate, alkyl phosphate; stearates (e.g., zinc stearate); and mixtures thereof.

[0051] In a three-layer substrate configuration, it is preferable that the first and second outer layers have the same composition. Such an implementation not only simplifies the manufacturing process but also offers advantages in terms of expansion and contraction behavior due to its symmetrical profile.

[0052] The substrate layer preferably has a tensile modulus of 30 to 80 N / mm in the longitudinal direction (MD). 2 More preferably 40 to 60 N / mm 2And / or a tensile modulus in the transverse direction (TD) of 20 to 60 N / mm 2 More preferably 30 to 50 N / mm 2 Alternatively or additionally, the substrate layer preferably has an elongation at break (MD) of 150 to 850%, more preferably 200 to 700%, and / or an elongation at break (TD) of 200 to 900%, more preferably 250 to 850%. Furthermore, the tensile strength (MD) of the substrate layer can be between 15 and 45 N / mm². 2 More preferably 20 to 40 N / mm 2 Within the range, and / or tensile strength (TD) can be from 5 to 30 N / mm. 2 More preferably 10 to 25 N / mm 2 Within the specified range. Tensile modulus, elongation at break and tensile strength can be determined according to ISO 527(1-3).

[0053] In another preferred embodiment, the substrate layer exhibits dimensional stability of less than 10% on both MD and TD, more preferably less than 5%, and particularly preferably less than 2%. Dimensional stability can be measured according to DIN 53377 when heated at 80°C for 1 hour.

[0054] Preferably, the tear resistance of the substrate layer on both MD and TD, as determined according to ISO 6383-2, is greater than 500 N / cm, more preferably at least 700 N / cm, and particularly preferably at least 1000 N / cm.

[0055] The pressure-sensitive adhesive layer may be in contact with the first outer layer and / or the second outer layer (if present) to adhere to the wafer. Alternatively, a pressure-sensitive adhesive layer may be disposed on each side of the substrate.

[0056] The surface of the substrate on which the pressure-sensitive adhesive layer is disposed may be subjected to physical or chemical treatment to promote and / or improve the bonding between the substrate and the adhesive layer, such as plasma or corona discharge treatment.

[0057] There are no particular limitations on the pressure-sensitive adhesive layer, and its composition can be suitably selected by those skilled in the art from materials known in the art. Examples of adhesive compositions include rubber adhesives, acrylic adhesives, silicone adhesives, and thermoplastic elastomers such as styrene-based and olefin-based elastomers. The pressure-sensitive adhesive layer may consist of radiation-curing adhesives whose adhesion is reduced by radiation rays or thermosetting adhesives whose adhesion is reduced by heat. Examples of radiation-curing adhesives preferably include UV-curing adhesives.

[0058] The pressure-sensitive adhesive layer preferably has a thickness of 1 to 100 μm, more preferably 2 to 50 μm, and particularly preferably 3 to 20 μm, in order to suppress an excessive increase in vibration amplitude that typically occurs during the dicing of semiconductor wafers, thereby reducing dicing defects or chipping of the wafer.

[0059] Prior to use in the cutting process, each adhesive side of the cutting strip may optionally be protected by a release liner, or may be protected in the form of a roll having a release liner having a release surface on each side. The release liner can serve as a protective material for the pressure-sensitive adhesive layer and can be peeled off when the sheet is laminated onto the workpiece. There are no particular limitations on the release liner, and it may include a release layer (a peel-treated layer) on at least one surface of the release liner substrate, such as a low-tack release liner containing a fluoropolymer and a low-tack release liner containing a non-polar polymer.

[0060] The total thickness of the cutting strip (excluding optional release liner) is preferably in the range of 50 to 300 μm, and more preferably in the range of 80 to 200 μm.

[0061] The thickness of the base layer preferably constitutes more than 50% of the total thickness of the base layer, the first outer layer, and the second outer layer (if present). In a preferred embodiment, the thickness of the base layer is typically in the range of 30-150 μm. In a two-layer substrate configuration, the base layer preferably has a thickness of 45 to 150 μm, and in a three-layer substrate configuration, the base layer preferably has a thickness of 30 to 120 μm.

[0062] The thickness of the first outer layer is typically in the range of 2-80 μm, more preferably 5-50 μm. However, in a two-layer substrate configuration, the first outer layer preferably has a thickness of 5 to 40 μm, and in a three-layer substrate configuration, the base layer preferably has a thickness of 10 to 50 μm, particularly preferably 10 to 25 μm.

[0063] The thickness of the second outer layer is typically in the range of 2-80 μm, more preferably 5-50 μm, further preferably 7-50 μm, and particularly preferably 10-25 μm. If the first and second outer layers have the same composition, it is preferable that their thickness difference is less than 10 μm, more preferably less than 5 μm, and particularly preferably less than 2 μm, for example, less than 1 μm.

[0064] Given the composition of the substrate layer, the aforementioned thickness range provides a particularly favorable balance between the tensile properties, stiffness, and tear strength of the cutting strip, and thus enables cutting with improved cutting quality.

[0065] Furthermore, if the weight ratio of polyolefin copolymer to filler in the outer layer is lower than that in the base layer, the elongation modulus of the outer layer will generally be higher than that of the base layer. A thin outer layer (e.g., 5 to 40 μm thick (two-layer) or 10 to 25 μm thick (three-layer)) has the advantage that the strip can be stretched with lower force while maintaining good die cutability.

[0066] Cutting method

[0067] In a second embodiment, the present invention relates to a dicing method comprising the steps of: mounting a semiconductor wafer onto a dicing tape according to a first embodiment, dicing the semiconductor wafer, optionally expanding the dicing tape, and separating the diced semiconductor wafer from the dicing tape.

[0068] Figure 3 An exemplary cutting method is shown in the figure.

[0069] A semiconductor wafer (31a) typically manufactured in a large-diameter state (which is not particularly limited and may be made of, for example, silicon, gallium, or arsenic) is first mounted onto the dicing tape described in relation to the first embodiment above, preferably by adhering it to a pressure-sensitive adhesive layer (33) of the dicing tape. The dicing tape may be secured in a retaining frame (32).

[0070] Subsequently, the semiconductor wafer (31a) is cut while still attached to the cutting tape.

[0071] In the cutting step, a method of cutting the semiconductor wafer (31a) with a cutting blade can be used. Blade cutting is prone to producing minute defects (also known as "chipping") on the semiconductor chip (32b). It is preferable to adjust the cutting depth so that the blade only contacts or partially cuts through the outer layer near the wafer, while keeping the substrate intact, thus minimizing the appearance of burrs and whiskers due to the rigidity of the outer layer. Therefore, the use of a cutting strip according to the invention is particularly advantageous when using a blade cutting method.

[0072] Alternatively, the stealth dicing method can be used to diced an ultrathin semiconductor wafer (31a), for example, by irradiating the semiconductor wafer (31a) with a laser beam such that the focal point of the laser beam is located inside the semiconductor wafer, thereby forming a brittle modified portion inside the semiconductor wafer (31a) as a result of multiphoton absorption.

[0073] Cutting is done along parallel and vertical lines to ultimately obtain the desired chip / square from the wafer.

[0074] Subsequently, the dicing tape attached to the back surface of the semiconductor wafer can be extended. This extension step is typically performed regardless of whether the dicing process is carried out using a blade dicing method or a stealth dicing method. When the dicing process is carried out using a stealth dicing method, the extension step, as described above, additionally functions as a step of dividing the semiconductor wafer with the dicing lines formed into individual semiconductor chips (31b).

[0075] The diced semiconductor wafer (31b) (i.e., the chip) is then separated from the dicing tape by picking it up from the tape. While not limited to this, chucks and needles can be used to remove the chip from the dicing tape.

[0076] Method for manufacturing cutting strip

[0077] The method for manufacturing the cutting strip according to the first embodiment described above is not particularly limited, and several methods known in the art can be used.

[0078] The method for manufacturing individual sublayers of the substrate (i.e., the base layer and the first and second outer layers) can be carried out using conventionally known film-forming methods, such as calendering, casting, expansion extrusion, T-die extrusion, etc. Multilayer films can then be prepared using conventional film lamination methods such as co-extrusion or dry lamination.

[0079] However, according to a third embodiment of the invention, the cutting strip is produced by a multilayer blown film extrusion process. It has been shown that the resulting film structure exhibits advantageous isotropic properties compared to cast multilayer films, and further reduces the shrinkage tendency of the resulting cutting strip, thereby enabling more consistent quality and performance of the cutting strip.

[0080] A pressure-sensitive adhesive layer is typically disposed on a multilayer substrate film. As mentioned above, the surface of the substrate on which the pressure-sensitive adhesive layer is disposed may be subjected to physical or chemical treatments to promote and / or improve the bonding between the substrate and the adhesive layer, such as plasma or corona discharge treatment.

[0081] It should be understood that the present invention may employ any of the preferred features described above with respect to the first to third embodiments, and the preferred features may be combined in any combination except that at least some of the features are mutually exclusive combinations.

[0082] Example

[0083] Exemplary cutting strips comprising three substrate layers were prepared, designated Example 1 and Example 2. For this purpose, the compositions shown in Table 1 were blended and extruded as multilayer blown films to form a uniform multilayer substrate. The two examples are identical except for the thicknesses of the first outer layer, the base layer, and the second outer layer.

[0084] Table 1

[0085]

[0086] Adflex Q 190 F, commercially available from LyondellBasell, is a thermoplastic polyolefin (rTPO) with a density of 0.880 g / cm³, suitable for use in heterogeneous reactors. 3 (ISO 1183), melt flow rate 0.6 g / 10 min (230℃ / 2.16 kg; ISO 1133), tensile stress at break 10 MPa (ISO 527-1 / 2), flexural modulus 100 MPa (ISO 178), melt temperature 142℃ (ISO 11357-3). PP represents polypropylene homopolymer. As LLDPE, SABIC® LLDPE 118 NE is used, with a yield of 0.918 g / cm³. 3 Butene-linear low-density polyethylene with a density of 1.0 g / 10 min and a melt flow rate of 1.0 g / 10 min was used. Talc with an average particle size (d50) of 2-5 μm was used as a filler. An acrylic pressure-sensitive adhesive was applied to the multilayer substrates of both Examples 1 and 2.

[0087] The mechanical properties of Examples 1 and 2 were tested and compared with those of the commercially available Nitto V-8AR cutting tape (reference example), which comprises a PVC-based substrate with a thickness of 80 μm. The results are shown in Table 2.

[0088] Table 2

[0089]

[0090] 1) ISO 527(1-3); 2) Measured according to DIN 53377 at 80℃ / 1h; 3) ISO 6383-2

[0091] The above results demonstrate a high degree of similarity between the cutting tape of the present invention and PVC-based cutting tapes, particularly regarding tensile properties. The films according to Examples 1 and 2 exhibit excellent dimensional stability and tear resistance.

[0092] The force-strain properties measured for the membranes of Examples 1 and 2 and the reference example show... Figure 4 In the middle (longitudinal (MD)). No definite yield point was detected in the membrane according to the invention. Figure 5 The force-strain characteristics in the transverse direction (TD) (or transverse direction (CD)) are shown.

[0093] For comparison, two polyethylene films (excluding fillers) with a thickness of 80 μm were cut under the same conditions as in Examples 1 and 2 and labeled as Comparative Examples 1 and 2.

[0094] The cutting strips according to Examples 1 and 2 and the reference example are cut under normal cutting conditions.

[0095] The cut chips were independently examined under a microscope. The evaluation results are summarized in Table 3, where "+" indicates no or very small defects, "o" indicates small but acceptable defects, and "-" indicates significant and unacceptable defects.

[0096] Table 3

[0097]

[0098] The above results indicate that the cutting film according to the present invention exhibits superior cutting properties and mechanical relaxation characteristics comparable to or better than those of conventional PVC-based cutting films.

[0099] Once the above disclosure is given, many other features, modifications, and improvements will become apparent to those skilled in the art.

[0100] Figure Labels

[0101] 10 / 20 Cutting Strip

[0102] A substrate

[0103] 11 / 21 Grassroots

[0104] 12 / 22 First outer layer

[0105] 13 / 23 / 33 Pressure-sensitive adhesive layer

[0106] 24 Second outer layer

[0107] 31a chip

[0108] 31b wafer cutting

[0109] 32 Frames

Claims

1. A cutting strip, comprising: grassroots A first outer layer, which is disposed on the base layer and is different from the base layer, and Optional pressure-sensitive adhesive layer; The base layer and the first outer layer comprise polyolefin copolymers; The first outer layer contains organic or inorganic fillers in an amount of 3 to 25% by weight based on the total weight of the respective layers.

2. The cutting strip according to claim 1, further comprising a second outer layer different from the base layer, the second outer layer being disposed on the side of the base layer opposite to the first outer layer and comprising a polyolefin copolymer.

3. The cutting strip according to claim 2, wherein the first outer layer and the second outer layer independently contain organic or inorganic fillers in an amount of 3 to 25% by weight, preferably 5 to 22% by weight, and more preferably 10 to 20% by weight based on the total weight of each outer layer.

4. The cutting strip according to any one of claims 1-3, wherein the polyolefin copolymer is a polypropylene copolymer, preferably an ethylene-propylene copolymer, and more preferably a multi-step polymerized ethylene-polypropylene copolymer.

5. The cutting strip according to any one of claims 1-4, wherein the polyolefin copolymer is heterogeneous reactor thermoplastic polyolefin (rTPO).

6. The cutting strip according to any one of claims 1-5, wherein the polyolefin copolymer has an ethylene content of more than 13% by weight, preferably more than 14.5% by weight, and more preferably more than 17% by weight and less than 35% by weight, based on the total weight of the polyolefin copolymer.

7. The cutting strip according to any one of claims 1-6, wherein the flexural modulus of the polyolefin copolymer, as determined according to ISO 178, is from 50 MPa to 500 MPa, preferably from 60 MPa to 300 MPa, more preferably from 70 MPa to 200 MPa, particularly preferably from 75 MPa to 150 MPa, and / or wherein the melting temperature of the polyolefin copolymer, as determined according to ISO 11357-3, is above 120°C, preferably above 125°C, more preferably above 130°C, particularly preferably above 135°C.

8. The cutting strip according to any one of claims 1-7, wherein the first outer layer and, if present, the second outer layer independently comprise the polyolefin copolymer in an amount of 60 to 80% by weight based on the total weight of the respective layers, and / or wherein the substrate layer comprises the polyolefin copolymer in an amount of 85 to 100% by weight based on the total weight of the substrate layer.

9. The cutting strip according to any one of claims 1-8, wherein the organic or inorganic filler has an average particle size (d50) in the range of 1 to 10 μm, preferably in the range of 2 to 5 μm, as determined by laser diffraction.

10. The cutting strip according to any one of claims 1-9, wherein the filler is an inorganic filler selected from one or more of talc, clay, silica and calcium carbonate, preferably selected from talc and calcium carbonate, and more preferably talc.

11. The cutting strip according to any one of claims 1-10, wherein the first outer layer, the base layer and / or optionally the second outer layer independently comprises 2 to 25% by weight and preferably 5 to 20% by weight of low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE), based on the total weight of the respective layers.

12. The cutting strip according to claim 11, wherein the low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE) has an elastic modulus in the transverse direction (TD) ranging from 160 MPa to 600 MPa, preferably from 180 MPa to 400 MPa, and an elastic modulus in the longitudinal direction (MD) ranging from 140 MPa to 550 MPa, preferably from 170 MPa to 380 MPa, said elastic modulus being determined at 23°C according to ISO 527-3.

13. The cutting strip according to any one of claims 1-12, wherein it satisfies one or more of the following characteristics a) to e): a) The thickness of the base layer constitutes more than 50% of the total thickness of the base layer, the first outer layer, and, if present, the second outer layer; b) The thickness of the base layer is in the range of 30-150 μm; c) The total thickness of the cutting strip is in the range of 50-300 μm, preferably 80-200 μm; d) The thickness of the first outer layer is in the range of 2-80 μm, preferably 5-50 μm; and e) The thickness of the optional second outer layer is in the range of 2-80 μm, preferably 5-50 μm.

14. A cutting method comprising the following steps: The semiconductor wafer is mounted onto the diced tape according to any one of claims 1-13. Cut the semiconductor wafer. Optionally extend the cutting strip, and The cut semiconductor wafer is separated from the dicing strip.

15. A method for manufacturing a cutting strip according to any one of claims 1-13, wherein the cutting strip is produced by a multilayer blown film extrusion process.

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