Cutting-up method of gallium arsenide wafer

Abstract

The invention relates to the technical field of wafer cutting, and provides a cutting-up method of a gallium arsenide wafer, in a cutter grinding stage, two times of cutter grinding are achieved through a cutter grinding plate, on one hand, diamonds of a grinding wheel blade can be exposed, a chip pocket is generated, on the other hand, the grinding wheel blade can be rounded, it is guaranteed that the grinding wheel blade and a main shaft are concentric, and the cutting-up efficiency is improved. Moreover, the cutting edge part in contact with the knife sharpening plate can be damaged during knife sharpening each time, and the cutting edge of the grinding wheel blade can be changed into a V shape, so that the purpose of trimming the shape of the cutting edge is achieved, the contact area between the cutting edge and a material is smaller in the product cutting process, the impact crushing impact force on the material is smaller, the breakage and cracks of particles after cutting can be obviously reduced, and the product quality is improved. The cutting quality of the wafer is improved, so that the yield of wafer products is improved; in the cutting-up stage, the wafer is preferentially divided into a plurality of stepping wide-strip-shaped cutting channels, and then fine division is carried out, so that the material stress can be preliminarily released, and the large area of the wafer wide strip is enough to resist the crack extension problem.

Description

Technical Field

[0001] The invention relates to the technical field of wafer cutting, and in particular to a gallium arsenide wafer dicing method. Background Art

[0002] With the vigorous development of the LED industry, different links are accumulating innovation. Especially in recent years, small-pitch LEDs have continued to grow, and Mini / MicroLEDs have achieved a qualitative change from quantitative change. With the release of the Mini / MicroLED market in the future, its upstream LED chips will be the core beneficiary. LED chips have a variety of substrate materials, and different substrates have different luminous colors. Among them, gallium arsenide, as a second-generation semiconductor material, is the most mature compound semiconductor material after "silicon". It has superior characteristics such as high frequency, high electron mobility, high output power, low noise and good linearity. It is widely used in the LED chip industry and is one of its preferred substrate materials.

[0003] Gallium arsenide belongs to the III-V group of compounds, with a sphalerite lattice structure. It is brittle and hard. Its material also has crystal orientation problems such as specific angle molding, which makes its processing difficulty significantly higher than the first-generation semiconductor material "silicon". Problems such as cracks and collapse are very likely to occur during processing. In addition, the toxicity of gallium arsenide has not been fully studied because it contains highly toxic As. Although the crystals of gallium arsenide are very stable, the small amount of gallium arsenide absorbed by the body is negligible. However, As cannot appear in the entire processing process, so the laser ablation processing method cannot be used (As is easily decomposed under high temperature conditions). At present, the commonly used method for dividing materials into small particles in the semiconductor industry is grinding wheel scribing in addition to laser ablation. However, when used in the LED chip industry, gallium arsenide will be processed into 4-inch wafers with a thickness of about 150um. Due to the characteristics of grinding, the gallium arsenide wafer will have a certain degree of warpage. The size of the pattern particles on it is basically 95~170um, and the back of the wafer is coated with a layer of gold. In addition, the gallium arsenide material is hard and brittle and cannot be divided by laser ablation. In the process of grinding wheel scribing and dividing the pattern particles, the particles are very easy to break and collapse, thereby damaging the chip. Summary of the invention

[0004] The object of the present invention is to provide a gallium arsenide wafer dicing method to solve the problem that the existing gallium arsenide wafer dicing method easily causes chipping and damage of the wafer.

[0005] In order to solve the above problems, the present invention provides a gallium arsenide wafer dicing method, comprising: S100, installing a grinding plate with a particle size matching the grinding wheel blade at a predetermined position of a cutting work disk of a dicing machine; S200, setting the sharpening parameters and starting the dicing machine, first controlling the grinding wheel blade to cut into the sharpening plate to a depth not less than the thickness of the GaAs wafer to be cut, and then controlling the grinding wheel blade to cut into the sharpening plate to a depth of 1 / 4 to 1 / 2 of the thickness of the GaAs wafer to be cut; S300, removing the grinding plate, installing the grinding silicon wafer on a predetermined position of the cutting work plate, and controlling the depth of the grinding wheel blade cutting into the grinding silicon wafer to be 1 / 2 to 3 / 4 of the thickness of the gallium arsenide wafer to be cut; S400, remove the grinding silicon wafer and set the cutting parameters, fix the gallium arsenide wafer to be cut at a predetermined position of the cutting work disk, and control the grinding wheel blade to cut according to the cutting parameters; the cutting parameters include a cutting process, and the cutting process includes a first channel step, a second channel step, and a third channel step set in sequence; wherein, the first channel step is 3 to 7 times the particle theoretical step, the second channel step is perpendicular to the first channel step, and the steps are cut in sequence according to the particle theoretical step; the third channel step is to complete the remaining cutting paths of the first channel step.

[0006] Optionally, before S100, the method includes: A sharpening plate with a particle size matching that of the grinding wheel blade is selected; the particle size of the sharpening plate is close to or consistent with the hard particle size of the grinding wheel blade.

[0007] Optionally, the particle size of the sharpening plate is 4000#~5000#, and the particle size of the grinding wheel blade is 4800#~5000#.

[0008] Optionally, in S100, the step of installing a grinding plate having a particle size matching that of a grinding wheel blade at a predetermined position of a cutting work disk of a dicing machine comprises: The selected grinding plate is fixed on the central area of ​​the sticky substrate film with an adhesive force greater than 120N / 25mm, and fixed with a metal ring matching the cutting work disk, so that the grinding plate, the sticky substrate film and the metal ring form a whole. The grinding plate is fixed by magnetically adsorbing the metal ring through the metal edge of the cutting work disk surface and adsorbing the sticky substrate film through the vacuum suction cup of the dicing machine.

[0009] Optionally, in S200, the knife sharpening parameters specifically include: The setting range of the sharpening speed is 30000rpm~45000rpm, and the sharpening cutting speed is 5mm / s~40mm / s.

[0010] Optionally, in S200, the knife sharpening parameters further include: According to the thickness of the grinding wheel blade installed on the equipment, set the step size for each grinding and cutting to 5 to 10 times the thickness of the grinding wheel blade; the cooling water flow rate for grinding wheel blade cutting should not be less than 1L / min.

[0011] Optionally, in S400, controlling the grinding wheel blade to perform cutting according to the cutting parameters further includes: When scribing, the depth of the grinding wheel blade cutting into the substrate of the gallium arsenide wafer must be accurately controlled, and the material layer of the gallium arsenide wafer must be cut through at the same time.

[0012] Optionally, in S400, the cutting parameters specifically include: The cutting speed setting range is 30000rpm~45000rpm, and the product cutting speed is 15mm / s~60mm / s.

[0013] Optionally, in S400, the cutting parameters further include: The cutting depth is set to cut into the adhesive substrate film 0.5μm ~ 4μm, and the cooling water flow rate during the cutting of the grinding wheel blade is not less than 1L / min.

[0014] The present invention has at least the following technical effects: The gallium arsenide wafer dicing method provided by the present invention realizes two sharpenings by means of the sharpening plate in the sharpening stage, which can expose the diamond of the grinding wheel blade and generate a chip groove on the one hand, and round the grinding wheel blade on the other hand to ensure that the grinding wheel blade is concentric with the main shaft, and each sharpening will cause the blade part in contact with the sharpening plate to be worn, so after two sharpenings from deep to shallow, the blade of the grinding wheel blade will become a "V" shape, so as to achieve the purpose of trimming the blade shape, so that the contact area with the material is less during the dicing process, and the impact force on the material is reduced. It is smaller and has a smaller area in contact with the metal on the back of the material. It is especially suitable for hard, brittle, thin and gold-backed materials such as gallium arsenide wafers. It can significantly reduce the chipping and cracking of particles after segmentation, which is beneficial to improving the cutting quality of the wafer, thereby improving the yield of wafer products. In addition, in the dicing stage, the gallium arsenide wafer is preferentially segmented into multiple stepped wide strip cutting paths (that is, the spacing between the cutting paths is greater than that of a single particle), and then finely divided. This can initially release the material stress. Since the wide strip area of ​​the wafer is large enough to resist the problem of crack extension, the cutting quality of the wafer is further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 A flow chart of a gallium arsenide wafer dicing method provided in an embodiment of the present invention.

[0017] Figure 2 A schematic diagram of a step-by-step scribing trajectory according to a first channel in a gallium arsenide wafer scribing method provided by an embodiment of the present invention; Figure 3 A schematic diagram of a second channel step-by-step scribing trajectory in a gallium arsenide wafer scribing method provided by an embodiment of the present invention; Figure 4 A schematic diagram of a step-by-step scribing trajectory according to a third channel in a gallium arsenide wafer scribing method provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0018] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] Those skilled in the art will understand that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by those skilled in the art in the field to which the present invention belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined as here.

[0020] Those skilled in the art will appreciate that, unless otherwise stated, the singular forms "a", "an", "said" and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present invention refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. The term "and / or" used herein includes all or any unit and all combinations of one or more associated listed items.

[0021] The sharpening process and slicing method of gallium arsenide wafers is a new method based on the grinding wheel slicing machine equipment. The slicing mechanism of the grinding wheel slicing machine is that the grinding wheel blade is driven by the main shaft to rotate at high speed to hit the damaged material to form the division of the material. The main role in the process of impacting and breaking the material is played by the exposed hard particles (i.e. diamond) on the grinding wheel blade and the surrounding chip grooves. The quality of these two points will directly affect the size of the chipping and cracking produced after the material is divided. At the same time, due to the characteristics of gallium arsenide wafers such as hardness, brittleness and thinness, the stress characteristics of its material and the shape of the grinding wheel blade also have a great influence on the particle chipping and cracking after segmentation, thereby affecting the yield of the wafer. Therefore, an embodiment of the present invention provides a slicing method for gallium arsenide wafers to solve the problem that the existing cutting method easily causes chip breakage and affects the yield.

[0022] The technical solution of the present invention and how the technical solution of the present invention solves the above-mentioned technical problems are described in detail below with specific embodiments.

[0023] like Figure 1 As shown, an embodiment of the present invention provides a gallium arsenide wafer dicing method, comprising the following steps S100-S400: S100, installing a grinding plate whose particle size matches the grinding wheel blade at a predetermined position of a cutting work disk of a dicing machine.

[0024] Specifically, the selected grinding plate is fixed on the central area of ​​the sticky substrate film with an adhesive force greater than 120N / 25mm, and fixed with a metal ring matching the cutting work disk, so that the grinding plate, the sticky substrate film and the metal ring form a whole. The grinding plate is fixed by magnetically adsorbing the metal ring by the metal edge of the cutting work disk surface and adsorbing the sticky substrate film by the vacuum suction cup of the dicing machine.

[0025] Optionally, before S100, the method includes: Choose a grinding plate with a particle size that matches the particle size of the grinding wheel blade; the particle size of the grinding plate is close to or consistent with the hard particle size of the grinding wheel blade. Because if the particle size (hard particle size) of the grinding plate is too large, it will cause excessive wear during sharpening and short blade life; when the particle size of the grinding plate is too small, it will cause insufficient diamond exposure and poor roundness of the grinding wheel blade. Therefore, correctly selecting the particle size of the grinding plate is an indicator to ensure a good cutting effect after sharpening. For example: the particle size of the grinding plate is 4000#~5000#, and the particle size of the grinding wheel blade is 4800#~5000#.

[0026] S200, setting the sharpening parameters and starting the dicing machine, first controlling the grinding wheel blade to cut into the sharpening plate to a depth not less than the thickness of the GaAs wafer to be cut, and then controlling the grinding wheel blade to cut into the sharpening plate to a depth of 1 / 4 to 1 / 2 of the thickness of the GaAs wafer to be cut.

[0027] By using the grinding plate to sharpen the blade twice, on the one hand, the diamond of the grinding wheel blade can be exposed and a chip groove can be produced, and on the other hand, the grinding wheel blade can be rounded to ensure that the grinding wheel blade and the spindle are concentric. Moreover, each sharpening will cause the blade part in contact with the grinding plate to be damaged. Therefore, after two sharpenings from deep to shallow, the blade of the grinding wheel blade will become a "V" shape, thereby achieving the purpose of trimming the blade shape. Compared with the conventional "U"-shaped grinding wheel blade, the "V"-shaped grinding wheel blade has less contact area with the material during the product cutting process, has less impact force on the material, and has a smaller area of ​​contact with the metal on the back of the material. It is especially suitable for hard, brittle, thin and gold-backed materials such as gallium arsenide wafers, and can significantly reduce the chipping and cracking of particles after segmentation, which is beneficial to improving the cutting quality of the wafer, thereby improving the yield of the wafer product.

[0028] Optionally, the sharpening speed setting range is 30000rpm~45000rpm, and the sharpening cutting speed is 5mm / s~40mm / s. Too low speed will cause the risk of blade breakage, while too high speed will produce a greater impact force and cause the blade to become serpentine. The sharpening and cutting speed is also a key parameter. Too slow sharpening and cutting speed affects efficiency, while too fast sharpening and cutting speed causes excessive blade load and easy blade breakage.

[0029] According to the thickness of the grinding wheel blade installed on the equipment, set the step of each sharpening and cutting to 5 to 10 times the thickness of the grinding wheel blade. If the step distance is too small, it will affect the sharpening effect, but if the step distance is too large, it will cause waste of the sharpening plate and increase costs. The cooling water flow rate of the grinding wheel blade cutting is not less than 1L / min, which is conducive to improving the blade forming. The setting of the cutting depth and sharpening sequence refers to the key parameters of the sharpening plate mentioned above. According to the linear speed direction of the blade rotation, select the corresponding cutting mode for cutting.

[0030] S300, remove the sharpening plate, install the sharpened silicon wafer on the predetermined position of the cutting work disk, and control the depth of the grinding wheel blade cutting into the sharpened silicon wafer to be 1 / 2~3 / 4 of the thickness of the gallium arsenide wafer to be cut.

[0031] Specifically, the grinding wheel blade is first sharpened twice by the sharpening plate in step S200, and then sharpened for the third time by the sharpening silicon wafer in step S300, aiming to further improve the cutting edge state and end shape of the grinding wheel blade, so that the diamond is better exposed and more chip grooves are produced, so that the current cutting edge and shape of the grinding wheel blade are more suitable for cutting hard, brittle and thin materials such as gallium arsenide wafers.

[0032] The sharpening parameters when sharpening the silicon wafer can be referred to the sharpening parameters when sharpening the sharpening plate in step S200, and will not be repeated here.

[0033] S400, remove the grinding silicon wafer and set the cutting parameters, fix the GaAs wafer to be cut at the predetermined position of the cutting work disk, and control the grinding wheel blade to cut according to the cutting parameters; the cutting parameters include the cutting process, and the cutting process includes the first channel stepping, the second channel stepping and the third channel stepping set in sequence; wherein, the first channel stepping is 3 to 7 times the particle theoretical stepping, the second channel stepping is perpendicular to the first channel stepping, and the cutting is sequentially performed according to the particle theoretical stepping; the third channel stepping is to complete the remaining cutting paths of the first channel stepping. The particle theoretical stepping can be understood as a single particle (the side length of the smallest wafer unit).

[0034] Specifically, refer to Figure 2~Figure 4 First, fix the LED gallium arsenide chip on the film with a base material of PVC material, place it in the center area of ​​the film, and fix it with a metal ring that matches the working disk of the dicing machine. The chip, film and metal ring form a whole. Then, the film is heated and baked to adjust the viscosity of the film. Finally, the metal edge of the metal ring is magnetically adsorbed on the surface of the working disk of the dicing machine, and the vacuum suction cup of the dicing machine adsorbs the film with a negative pressure of not less than 80kpa, thereby achieving the fixation of the gallium arsenide chip.

[0035] In the specific cutting process, the entire cutting process is divided into three stages: Figure 2 As shown, for example, firstly along the first direction, every interval of 3 to 7 times of the theoretical particle step (for example: 5 times of the theoretical particle step), that is, firstly performing large-pitch scribing and cutting, is conducive to the initial release of stress; as Figure 3 As shown, then step along the second direction according to the particle theory, the second direction is perpendicular to the first direction; Figure 4 As shown, the particles within the large spacing are finally subdivided and sliced ​​to obtain multiple individual grains. It can be understood that the spacing of the first channel step is 3 to 7 times the theoretical particle step. If the spacing is too small, stress will affect the edge collapse, but if the spacing is too large, the stress cannot be released well.

[0036] It should be noted that, since most common LED gallium arsenide wafers are 4-inch round wafers, they will have a certain amount of deformation (i.e., stress) after the grinding process. The final particle size of this type of wafer material is relatively small (generally, particles of 90 to 140 um square). If the particles are cut according to the step size, they will be too small and will most likely cause cracks or serious chipping due to resistance to stress release. Therefore, the present invention preferentially divides the gallium arsenide wafer into a plurality of stepped wide strip cutting paths (i.e., the spacing between the cutting paths is greater than that of a single particle). In this way, the material stress can be initially released because the wide strip area is large enough to resist the problem of crack extension.

[0037] In addition, because the LED gallium arsenide wafer is hard, brittle and thin and has a layer of gold plating on the back, the grinding wheel blade will contact the metal and film on the back when cutting the wafer. Both materials pose a risk of blade clogging, which seriously affects the sharpness of the blade and causes chipping or cracking on the back of the particle. When cutting, the depth of the grinding wheel blade cutting into the substrate of the gallium arsenide wafer must be precisely controlled, and the material layer of the gallium arsenide wafer must be cut through at the same time. This can effectively solve the problem of the metal layer on the back of the material and the substrate film wrapping the blade during the continuous cutting process of the gallium arsenide wafer, resulting in reduced blade cutting ability.

[0038] Optionally, the cutting parameters in this embodiment specifically include: the cutting speed setting range is 30000rpm~45000rpm, the product cutting speed is 15mm / s~60mm / s; the cutting depth is set to cut into the sticky substrate film 0.5μm~4μm, and the cooling water flow rate during cutting of the grinding wheel blade is not less than 1L / min.

[0039] The gallium arsenide wafer dicing method provided by the embodiment of the present invention is used to process LED gallium arsenide wafers, without high-temperature melting and other destructive effects on crystal materials, and will not produce thermal decomposition to generate toxic substances. The physical dicing method has low pollution and is more conducive to green and sustainable development. In addition, the dicing accuracy can be controlled within the micron range, which can meet the precision processing requirements of various industries, and the product size obtained by dicing is high in precision and strong in practicality. The entire dicing operation process is simple, the process flow is coherent, and can meet the needs of gallium arsenide materials of various sizes and thicknesses. Compared with the laser cutting method, there is no subsequent manual splitting process, which is suitable for industrial production, can reduce the risks caused by manual operation errors, and has higher work efficiency. In addition, the consumables in the entire dicing process are low in price, low in consumption, and less in subsequent processes, which can reduce unnecessary labor costs. The early power supply and the later emission detection equipment are simple to build, which can greatly reduce the production cost, and significantly improve the quality and yield of LED chips, indirectly greatly reduce the manufacturing cost of chips, and provide a favorable guarantee for the mass industrial production of LED chips.

[0040] The above contents of the present invention are specifically described below by taking specific embodiments as examples: Example 1 An embodiment of the present invention provides a gallium arsenide wafer dicing method, comprising the following steps: S100, installing a grinding plate whose particle size matches the grinding wheel blade at a predetermined position of a cutting work disk of a dicing machine.

[0041] S200, setting the sharpening parameters and starting the dicing machine, first controlling the grinding wheel blade to cut into the sharpening plate to a depth not less than the thickness of the GaAs wafer to be cut, and then controlling the grinding wheel blade to cut into the sharpening plate to a depth of 1 / 3 of the thickness of the GaAs wafer to be cut.

[0042] Specifically, the first time the knife was trimmed using the F50 sharpening board, the blade cut into the sharpening board 150 μm, the rotation speed was 35000 rpm, the feed speed was 20 mm / s, and the number of cuts was 20; the second time the knife was trimmed using the F50 sharpening board, the blade cut into the sharpening board 50 μm, the rotation speed was 35000 rpm, the feed speed was 20 mm / s, and the number of cuts was 15.

[0043] S300, remove the sharpening plate, install the sharpened silicon wafer on the predetermined position of the cutting work disk, and control the depth of the grinding wheel blade cutting into the sharpened silicon wafer to be 2 / 3 of the thickness of the gallium arsenide wafer to be cut.

[0044] Specifically, the third time the sharpening knife is used for pre-cutting of silicon wafers, the cutting depth should be 100 μm, the rotation speed should be 40,000 rpm, the feed speed should be 20 mm / s, and the number of cuts should be 50.

[0045] S400, remove the grinding silicon wafer and set the cutting parameters, fix the gallium arsenide wafer to be cut at a predetermined position of the cutting work disk, and control the grinding wheel blade to cut according to the cutting parameters; the cutting parameters include a cutting process, and the cutting process includes a first channel step, a second channel step, and a third channel step set in sequence; wherein the first channel step is 5 times the particle theoretical step, the second channel step is perpendicular to the first channel step, and the steps are cut in sequence according to the particle theoretical step; the third channel step is to complete the remaining cutting paths of the first channel step.

[0046] Specifically, an LED gallium arsenide wafer to be cut has a size of 4 inches, a thickness of 0.15 mm, a gold back, and a single product particle size of 0.1 mm*0.1 mm (ie, a single particle has a side length of 0.1 mm) as an example for illustrative description.

[0047] First, the first direction (depending on the design angle of the customer's wafer) is cut, the spindle speed is 40000rpm, the grinding wheel feed speed is 35mm / s, the grinding wheel cutting blade height is 0.072mm (cutting into the film 3um), and the stepping is 0.4mm (4 times the theoretical particle stepping).

[0048] Then, the second direction of the cutting is performed, the spindle speed is 40000rpm, the grinding wheel feed speed is 55mm / s, the grinding wheel cutting blade height is 0.072mm, and the stepping is 0.1mm.

[0049] Finally, repeat the cutting in the first direction, but the position is different from the cutting position in the first direction. The knife landing point is located at the cutting position in the first direction with an overall offset of 0.1mm, that is, one step. The spindle speed is 40000rpm, the grinding wheel feed speed is 25mm / s, the grinding wheel cutting knife height is 0.072mm, and the steps are 0.1mm and 0.2mm respectively, that is, the uncut parts in the first direction are cut, and the cooling water flow rate of the grinding wheel is 1.3L / min.

[0050] Example 2 The method of Example 1 is referred to, except that in step S200, the depth of the grinding wheel blade cutting into the grinding plate is controlled to be 1 / 4 of the thickness of the gallium arsenide wafer to be cut, which is smaller than the depth of Example 1, and the "V" shape trimmed is not obvious enough, and the sharpness is limited.

[0051] Example 3 The method of Example 1 is followed, except that in step S200, the depth of the grinding wheel blade cutting into the grinding plate is controlled to be 1 / 2 of the thickness of the gallium arsenide wafer to be cut, which is larger than the depth of Example 1, and the "V" shape is too obvious, which will significantly reduce the strength of the blade to a certain extent, and the blade is easy to break during cutting.

[0052] Example 4 The method of Example 1 is referred to, except that in step S300, the depth of the grinding wheel blade cutting into the grinding silicon wafer is controlled to be 1 / 2 of the thickness of the gallium arsenide wafer to be cut.

[0053] Example 5 The method of Example 1 is referred to, except that, in step S400, the first channel step is cut at a step size of 7 times the theoretical step size of the particle.

[0054] Comparative Example 1 Different from Example 1, in Comparative Example 1, the knife sharpening was performed only once using the knife sharpening plate.

[0055] Comparative Example 2 Different from Example 1, the cutting method in Comparative Example 2 is only a single particle step along the first direction.

[0056] Comparative Example 3 Different from Example 1, in step S200 of Comparative Example 3, the depth of the grinding wheel blade cutting into the grinding plate is controlled to be 1 / 6 of the thickness of the gallium arsenide wafer to be cut.

[0057] Comparative Example 4 Different from Example 1, in step S200 of Comparative Example 4, the depth of the grinding wheel blade cutting into the grinding plate is controlled to be 2 / 3 of the thickness of the gallium arsenide wafer to be cut.

[0058] Comparative Example 5 Different from Example 1, in step S300 of Comparative Example 5, the depth of the grinding wheel blade cutting into the grinding silicon wafer is controlled to be 1 / 4 of the thickness of the gallium arsenide wafer to be cut.

[0059] Test Case By observing the particle samples of the above-mentioned embodiments and comparative examples after cutting under a microscope, the corresponding front edge chipping and back edge chipping conditions are obtained, as shown in Table 1 below.

[0060] Table 1 Statistics of chipping edges of various embodiments and comparative examples

[0061] From the above results, it can be seen that, compared with the comparative example, the embodiment of the present invention can significantly reduce the edge collapse size, which is beneficial to improving the wafer qualification rate. Further, according to Example 1 and Examples 2 to 5, it can be seen that the preferred dicing method of the present invention can reasonably control the edge collapse, which is more conducive to improving the wafer dicing quality while ensuring the dicing efficiency.

[0062] Those skilled in the art will appreciate that the various operations, methods, steps, measures, and schemes discussed in the present invention may be alternated, modified, combined, or deleted. Further, other steps, measures, and schemes in the various operations, methods, and schemes discussed in the present invention may also be alternated, modified, rearranged, decomposed, combined, or deleted. Further, the steps, measures, and schemes in the prior art that are similar to those disclosed in the present invention may also be alternated, modified, rearranged, decomposed, combined, or deleted.

[0063] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0064] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0065] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific conditions.

[0066] In the description of this specification, specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. It should be understood that although the steps in the flowchart of the accompanying drawings are displayed in sequence as indicated by the arrows, these steps are not necessarily performed in sequence in the order indicated by the arrows. Unless clearly stated herein, there is no strict order restriction on the execution of these steps, and they may be performed in other orders. Moreover, at least a portion of the steps in the flowchart of the accompanying drawings may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily performed at the same time, but may be performed at different times, and their execution order is not necessarily performed in sequence, but may be performed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A gallium arsenide wafer dicing method, characterized in that: include: S100, installing a grinding plate with a particle size matching the grinding wheel blade at a predetermined position of a cutting work disk of a dicing machine; S200, setting the sharpening parameters and starting the dicing machine, first controlling the grinding wheel blade to cut into the sharpening plate to a depth not less than the thickness of the GaAs wafer to be cut, and then controlling the grinding wheel blade to cut into the sharpening plate to a depth of 1 / 4 to 1 / 2 of the thickness of the GaAs wafer to be cut; S300, removing the grinding plate, installing the grinding silicon wafer on a predetermined position of the cutting work plate, and controlling the depth of the grinding wheel blade cutting into the grinding silicon wafer to be 1 / 2 to 3 / 4 of the thickness of the gallium arsenide wafer to be cut; S400, remove the grinding silicon wafer and set the cutting parameters, fix the gallium arsenide wafer to be cut at a predetermined position of the cutting work disk, and control the grinding wheel blade to cut according to the cutting parameters; the cutting parameters include a cutting process, and the cutting process includes a first channel step, a second channel step, and a third channel step set in sequence; wherein, the first channel step is 3 to 7 times the particle theoretical step, the second channel step is perpendicular to the first channel step, and the steps are cut in sequence according to the particle theoretical step; the third channel step is to complete the remaining cutting paths of the first channel step.

2. The gallium arsenide wafer dicing method according to claim 1, characterized in that: Prior to S100, including: A sharpening plate with a particle size matching that of the grinding wheel blade is selected; the particle size of the sharpening plate is close to or consistent with the hard particle size of the grinding wheel blade.

3. The gallium arsenide wafer dicing method according to claim 2, characterized in that: The particle size of the grinding plate is 4000#~5000#, and the particle size of the grinding wheel blade is 4800#~5000#.

4. The gallium arsenide wafer dicing method according to claim 1, characterized in that: In S100, the step of installing a grinding plate having a particle size matching that of a grinding wheel blade at a predetermined position of a cutting work disk of a dicing machine includes: The selected grinding plate is fixed on the central area of ​​the sticky substrate film with an adhesive force greater than 120N / 25mm, and fixed with a metal ring matching the cutting work disk, so that the grinding plate, the sticky substrate film and the metal ring form a whole. The grinding plate is fixed by magnetically adsorbing the metal ring through the metal edge of the cutting work disk surface and adsorbing the sticky substrate film through the vacuum suction cup of the dicing machine.

5. The gallium arsenide wafer dicing method according to claim 1, characterized in that: In S200, the knife sharpening parameters specifically include: The setting range of the sharpening speed is 30000rpm~45000rpm, and the sharpening cutting speed is 5mm / s~40mm / s.

6. The gallium arsenide wafer dicing method according to claim 1, characterized in that: In S200, the knife sharpening parameters also include: According to the thickness of the grinding wheel blade installed on the equipment, set the step size for each grinding and cutting to 5 to 10 times the thickness of the grinding wheel blade; the cooling water flow rate for grinding wheel blade cutting should not be less than 1L / min.

7. The gallium arsenide wafer dicing method according to claim 1, characterized in that: In S400, the step of controlling the grinding wheel blade to perform cutting according to the cutting parameters further includes: When scribing, the depth of the grinding wheel blade cutting into the substrate of the gallium arsenide wafer must be accurately controlled, and the material layer of the gallium arsenide wafer must be cut through at the same time.

8. The gallium arsenide wafer dicing method according to claim 1, characterized in that: In S400, the cutting parameters specifically include: The cutting speed setting range is 30000rpm~45000rpm, and the product cutting speed is 15mm / s~60mm / s.

9. The gallium arsenide wafer dicing method according to claim 1, characterized in that: In S400, the cutting parameters also include: The cutting depth is set to cut into the adhesive substrate film 0.5μm ~ 4μm, and the cooling water flow rate during the cutting of the grinding wheel blade is not less than 1L / min.

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