Method for sizing crystal rods

Abstract

The application provides a method for matching the length of a crystal bar, which is used for determining the length of a whole crystal bar which is spliced by a plurality of segmented crystal bars, and comprises the following steps: calculating the total splicing length L of the crystal bars which can be cut by a single winding cutting line; determining the minimum cutting times C and the planned splicing length D of the whole crystal bar which is cut at a time according to the actual maximum processable crystal bar length D of a slicing machine, wherein D M <D M , C×D M >L, C×D≤L; determining the value range of the actual splicing length D n of the whole crystal bar which is cut at a time, wherein 0.85D≤D n ≤1.15D)∩(D n ≤D M ); and splicing the plurality of segmented crystal bars into at least C whole crystal bars according to the value range of the actual splicing length D n , wherein the sum of the lengths of all the whole crystal bars is ΣD n ≤L.

Description

Technical Field

[0001] This invention relates to the field of crystal preparation technology, and in particular to a method for matching the length dimensions of crystal rods. Background Technology

[0002] Artificial crystals, such as sapphire and monocrystalline silicon, are typically processed into thin, plate-like wafers using wire cutting. First, before slicing, the solidified crystal ingot is divided into numerous segmented ingots. Then, several segmented ingots are selectively assembled and fixed along the axial direction to form a complete crystal ingot. The complete crystal ingot is then bonded to a substrate in a side-lying position. The substrate is then fixed to the slicing machine. The cutting wire is wound around the rollers of the slicing machine, forming a tension section. The rotation of the rollers drives the cutting wire to rotate at high speed, causing the tension section to move rapidly to saw the outer periphery of the crystal ingot.

[0003] Currently, there is a lack of overall planning for the assembly of whole crystal ingots. The assembly of whole crystal ingots in the initial cutting cycles at the beginning of slicing is based on the actual maximum processable crystal ingot length. However, the actual maximum processable crystal ingot length of the slicing machine is less than the theoretical maximum length of crystal ingots it can carry, and is determined by this theoretical maximum length. As the cutting wires are consumed, there may be a situation where there are fewer cutting wires remaining in a particular cutting cycle. Therefore, personnel need to record the slicing machine's operating cycles in real time, and before the operating cycle when the cutting wires are about to run out or the remaining wires are insufficient, to specifically assemble a shorter whole crystal ingot for the current cutting cycle based on the total length of crystal ingots that the remaining cutting wires can cut. The length of the assembled shorter whole crystal ingot must match the remaining cutting wire trace amount to ensure that the remaining cutting wires can cut this shorter whole crystal ingot.

[0004] The above situation leads to the following problems: Due to the limited remaining cutting line allowance, the total length of the shorter ingot segment that needs to be specially matched is short and significantly shorter than the previously matched ingot segment. Therefore, it may be difficult to find an ingot segment with a length shorter than the length corresponding to the remaining cutting line among many segmented ingots. Moreover, the length of the ingot segment that needs to be matched is too short, which increases the matching difficulty. It is difficult for personnel to efficiently and quickly select an individual of suitable length from many segmented ingots for accurate matching. Often, the length of the matched segment is much longer than the required matching length, which leads to a decrease in the efficiency of ingot slicing. In addition, the length of the ingot segment corresponding to the remaining cutting line is too short, which will also significantly increase the wafer cutting cost. However, if an ingot segment is not specially matched for the remaining cutting line, then the remaining cutting line will be wasted. Summary of the Invention

[0005] In view of this, the present invention provides a method for matching the length of a crystal rod, used to determine the length of a whole crystal rod formed by splicing multiple segmented crystal rods.

[0006] The method for aligning the length dimensions of crystal rods provided by this invention includes the following steps:

[0007] A. Calculate the total splicing length of the crystal rods that can be cut by a single dicing wire. L ;

[0008] B. Based on the actual maximum processable ingot length of the slicing machine D M Determine the minimum number of cuts. c And the planned splicing length of a single cut of an entire crystal rod. D ,in D ≤ D M , c × D M ≥ L , c × D ≤ L ;

[0009] C. Determine the actual splicing length of a single cut of the entire crystal rod. D n The value range of is (0.85). D ≤ D n ≤1.15 D )∩( D n ≤ D M );

[0010] D. Based on the actual splicing length D n The range of values ​​is used to splice multiple segmented crystal rods into at least c The sum of the lengths of all the complete crystal rod segments ∑ D n ≤ L .

[0011] In one embodiment, the actual maximum processable ingot length of the slicing machine is used. D M Determine the minimum number of cuts. c And the planned splicing length of a single cut of an entire crystal rod. D ,include:

[0012] B1. If the total splicing length of the crystal rods is... L Divisible D M Minimum number of cuts c = L / D M ;

[0013] B2. If the total splicing length of the crystal rods is... L Not divisible D M Minimum number of cuts c for L Divide by D M The integer value of the quotient is increased by one.

[0014] With this setup, the actual length of the entire crystal ingot cut in each round will not exceed the actual maximum processable crystal ingot length of the slicing machine. D M .

[0015] In one embodiment, the actual maximum processable ingot length of the slicing machine is used. D M Determine the minimum number of cuts. c And the planned splicing length of a single cut of an entire crystal rod. D ,include:

[0016] B3. Planned splicing length of a single cut of an entire crystal rod D = L / c .

[0017] In one implementation, the total splicing length of the crystal rods that can be cut by a single dicing wire is calculated. L ,include:

[0018] A1. Based on the total length of the single roll cutting line s The number of traces required for cutting a single wafer l Calculate the total number of wafers that a single dicing wire can cut. a , a = s / l ;

[0019] A2. Based on the specified thickness value of a single wafer. m Calculate the total splicing length of the crystal rods that can be cut by a single dicing wire. L , L = a × m .

[0020] In one embodiment, based on the actual splicing length D n The range of values ​​is used to splice multiple segmented crystal rods into at least c The sum of the lengths of all the complete crystal rod segments ∑ D n ≤ L ,include:

[0021] D1, at least c In a complete crystal rod segment, the actual splicing length D n Compared with the actual maximum processable ingot length of the slicing machine D M The number of equal whole crystal rods is no more than 2.

[0022] With this setting, the length dimension reaches D M The number of whole crystal rods is kept at a low level. This helps to avoid significant differences in the length of whole crystal rods corresponding to different cutting rounds, and reduces the standard deviation and variance of the length of all whole crystal rods. The closer the mating dimensions of the whole crystal rods are to each other, and the closer they are numerically to the planned splicing length, the better. D Therefore, the lower the overall difficulty of assembling the entire crystal rod and the less time it takes, the more conducive it is to improving the crystal slicing processing efficiency.

[0023] In one embodiment, based on the actual splicing length D n The range of values ​​is used to splice multiple segmented crystal rods into at least c The sum of the lengths of all the complete crystal rod segments ∑ D n ≤ L ,include:

[0024] D2, in the n The length of the shortest segment of the crystal rod obtained from the ( )th splicing is not less than the length of the shortest segment of the crystal rod obtained from the ( )th splicing. n +1) lengths of the longest segment of the crystal rod obtained from splicing the entire crystal rod, where 1≤n≤( c -1).

[0025] This setup, where segmented crystal rods are selected to assemble the entire crystal rod, follows the principle of selecting the longest rod first and those of similar length. This further improves assembly efficiency, reduces the number of segmented crystal rods required to form the entire crystal rod, and thus reduces the number of operations required to splice and fix the segmented crystal rods.

[0026] In one implementation, the first n The number of segmented crystal rods in the whole crystal rod obtained from the second splicing is not greater than that of the ()th splicing. n +1) The number of segmented crystal rods in the whole crystal rod obtained by splicing, where 1≤n≤( c -1).

[0027] With this setup, the selection of segmented crystal rods to assemble the whole crystal rod follows the principle of selecting the longest first and the shortest first, and selecting rods of similar length. This can further improve the assembly efficiency, reduce the number of segmented crystal rods that make up the whole crystal rod, and thus reduce the number of operations required to splice and fix the segmented crystal rods.

[0028] In one embodiment, based on the actual splicing length D n The range of values ​​is used to splice multiple segmented crystal rods into at least c The sum of the lengths of all the complete crystal rod segments ∑ D n ≤ L ,include:

[0029] D3. Based on the actual splicing length D n The range of values ​​is used to splice multiple segmented crystal rods into at least c The sum of the lengths of all the complete crystal rod segments ∑ D n ≤ L ,include:

[0030] Multiple segmented crystal rods spliced ​​together C n One complete crystal rod, 2 D M / 3≤ L / C n < D M .

[0031] With this configuration, the method for matching the length of the crystal rod in this invention balances both the quality of the wafer obtained after slicing the entire crystal rod and the overall slicing efficiency of the crystal rod, thus taking into account both wafer quality and slicing efficiency to a greater extent.

[0032] In one embodiment, the actual maximum processable ingot length of the slicing machine D M The minimum number of cuts is 600 mm. c The planned splicing length for a single cut of the entire crystal rod is 4. D It is 400mm~500mm.

[0033] In one embodiment, the total splicing length of the crystal rods that can be cut by the single-roll cutting wire is... L The actual splicing length of the single-cut crystal rod is 2000 mm. D n The value range is [350, 550).

[0034] Compared with the prior art, the method for matching the length dimensions of crystal rods in this invention has at least the following beneficial effects:

[0035] This invention specifies the required length of the entire crystal rod for each cutting round in crystal slicing. Whether it is in the first few cutting rounds of slicing or in the last cutting round when the cutting line is about to be exhausted, the length matching requirement of the entire crystal rod, specifically, the planned size range of the length matching of the entire crystal rod, is consistent.

[0036] The actual ingot splicing lengths corresponding to multiple cutting rounds tend to be consistent, thus fundamentally overcoming a series of problems such as the difficulty and time-consuming assembly of whole ingots in the last cutting round, the difficulty in obtaining ingot assembly lengths that match the cutting capacity of the remaining cutting lines, the difficulty in finding segmented ingots with lengths shorter than the whole ingot lengths corresponding to the remaining cutting lines, and the significant increase in wafer cutting costs caused by the excessively short lengths of the whole ingots corresponding to the remaining cutting lines. The reason for the series of problems listed above is the lack of overall planning for ingot assembly in the early cutting rounds and the blind assembly of whole ingots in the early cutting rounds according to the actual maximum processable ingot length of the slicing machine.

[0037] By pre-configuring the length of the entire ingot segment for each cutting round, the significant difference between the ingot length that the cutting wire can cut in the final cutting round and the ingot length cut in previous cutting rounds is avoided. This makes it easier to find ingot segments with a length shorter than the length of the entire ingot segment corresponding to the remaining cutting wire from among many ingot segments. The slicing efficiency of the ingots will not be dragged down by the difficulty, time-consuming process, and inability to meet the cutting capabilities of the remaining cutting wires in the final cutting round. It also reduces the cost of cutting wafers with the remaining cutting wires in the final cutting round and eliminates the problem of wasting the remaining cutting wires due to abandoning the ingot matching for the remaining cutting wires in the final cutting round. Detailed Implementation

[0038] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.

[0040] In the photovoltaic and semiconductor industries, wafers, made from artificial crystals, are widely used as important industrial materials. Currently, the industry commonly uses slicing machines to cut entire crystal rods using wire cutting to obtain wafers.

[0041] The slicing machine includes a support platform for fixing and mounting a whole crystal ingot, and a roller assembly with a cutting wire wound on it. The cutting wire can be diamond wire, and the rollers in the roller assembly can be grooved rollers. The grooved rollers allow the cutting wire to be arranged at equal intervals along the axial direction of the grooved rollers according to the groove pitch of the grooved rollers. The cutting wire forms multiple tension sections between two rollers. The tension sections are arranged in parallel at equal intervals along the axial direction of the rollers. The cutting wire is driven by the rotation of the rollers, and the tension sections can thus move rapidly along the tangential direction of the roller sidewall to saw the sidewall of the crystal ingot. A glass plate can be placed on the support platform, and the whole crystal ingot is fixed to the glass plate in a side-lying position. Specifically, the sidewall of the whole crystal ingot can be bonded to the glass plate.

[0042] The entire crystal ingot is bonded to a glass plate, which is then bonded to a feed holder, which is subsequently fixed to the slicing machine. During slicing, the glass plate is parallel to the axis of the rollers, and the axis of the entire crystal ingot is also parallel to the axis of the rollers. The cut surface formed by the wire cut of the entire crystal ingot is perpendicular to the axis of the entire crystal ingot. The multiple wafers obtained after the entire crystal ingot is cut by the wire cut have the same thickness, and the wafer thickness, the axial groove pitch of the grooved rollers, and the spacing between the multiple tensioning sections are consistent. It should be noted that the multiple wafers are not all the products obtained after cutting the entire crystal ingot; the products corresponding to the two ends of the entire crystal ingot may be discarded, and the multiple wafers are the remaining products.

[0043] The entire crystal rod is obtained as follows: After obtaining a complete solidified rod-shaped crystal (referred to as a solidified crystal rod) using crystal growth equipment, the solidified crystal rod is hollowed out. The solidified crystal rod is cone-shaped or frustum-shaped, with a large circular surface and a small circular surface facing away from each other. The hollowing process can be carried out from the large circular surface to the small circular surface or from the side wall of the solidified crystal rod. During the hollowing process, segmented crystal rods are generated. At the same time, parts with defects such as size and crystal quality are removed, and parts with good size and crystal quality are retained. The segmented crystal rods are the retained parts. Then, personnel need to fix and bond these segmented crystal rods along the axial direction and match them to a certain axial length. The whole obtained after multiple segmented crystal rods are bonded and fixed is the entire crystal rod.

[0044] To ensure that the dimensional accuracy and surface finish of the wafers meet relevant requirements, each segment of the crystal ingot can only be cut by the same dicing wire roll. It is not permissible to have a segment of the crystal ingot not yet cut, and the current dicing wire roll has been exhausted, requiring a new dicing wire roll to continue cutting the remaining segment. Furthermore, the length of the assembled crystal ingot must not exceed the length of the glass plate. Within a certain length range, the shorter the length of the crystal ingot, the lower the load on the slicing machine, the easier it is to cut the entire crystal ingot, and the higher the quality of the final wafer.

[0045] The dicing wire is procured externally by the chip manufacturer. The length of the dicing wire is known, and the chip manufacturer pre-purchases multiple rolls of dicing wire. The manufacturer cannot accurately calculate the amount of dicing wire needed based on production plans or the length of the entire ingot to be cut. Therefore, it is impossible to determine the exact length of dicing wire or the number of rolls required to cut a batch of entire ingots. To prevent a shortage of dicing wire and avoid situations where the dicing wire is exhausted before the entire ingot is cut, the manufacturer will procure as much dicing wire as possible.

[0046] Generally, the maximum actual ingot length that current mainstream slicing machines can process is 600 mm. If the length of the entire ingot is adjusted to match the maximum actual ingot length that current mainstream slicing machines can process, and the total ingot length that one roll of dicing wire can cut is 2000 mm, then at least four cuts are needed to use up one roll of dicing wire. Of course, the length of the entire ingot can also be reduced, which would require more cuts to use up the dicing wire. Although reducing the length of the entire ingot helps improve wafer quality, increasing the number of cuts will also lead to a decrease in wafer manufacturing efficiency.

[0047] Current chip manufacturers lack a comprehensive plan for assembling complete ingot segments. For example, if a slicing machine can process ingots up to 600mm in length, a single dicing wire can cut a total ingot length of 2000mm, and the minimum number of cuts required to use all the wires is four, in the first three slicing operations, the length of the ingot segment cut is always 600mm. This leaves only 200mm segments for the remaining wires. Therefore, the manufacturer needs to specifically prepare a 200mm ingot segment for the fourth cut, significantly shorter than the segments from the first three cuts. This leads to the following problems:

[0048] The following details the problems caused by excessively short lengths of the entire crystal ingot. Most segmented crystal ingots are between 100mm and 200mm in length. First, if the entire crystal ingot is too short, it may be impossible to select individual ingots shorter than the entire ingot from among many segments. For example, if the remaining cutting lines can only cut a 50mm segmented crystal ingot, it's impossible to find such a short segmented ingot. Second, the larger the length of the entire crystal ingot, the easier it is to select segmented ingots and assemble them to create an entire crystal ingot with a length close to the expected value. For example, selecting multiple segmented ingots within the 100mm-200mm length range to assemble a 600mm long crystal ingot is much easier than assembling a 200mm long crystal ingot. Assembling a 200mm crystal ingot requires significantly more time to select, eliminate, and verify the assembled length from numerous segmented ingots. This will severely impact the efficiency of wafer production. Third, the length of the remaining ingot corresponding to the remaining dicing wires—that is, the length of the ingot that the remaining dicing wires can cut—is too short, causing a significant increase in wafer cutting costs. For example, each operation of the slicing machine incurs depreciation costs of 1000 yuan. Additionally, each operation incurs auxiliary material costs, including the slurry adhered to and carried by the dicing wires, and the manufacturing cost of the slurry, totaling 1000 yuan. Both depreciation and auxiliary material costs are fixed for each cutting cycle and are unrelated to the length of the ingot. If a 500mm ingot is used to cut 500 wafers, each 1mm thick, the cost per wafer is 4 yuan. However, if a 30mm ingot is used to cut 30 wafers of the same thickness, the cost per wafer is 70 yuan, leading to severe losses. To avoid these severe losses, the only current solution to the problem of the remaining dicing wires being too short to cut is to abandon the remaining dicing wires altogether.

[0049] In view of the above problems, the present invention provides a method for assembling crystal rods, which is used to determine the length of a whole crystal rod composed of multiple segmented crystal rods. The method includes the following steps:

[0050] S10. Calculate the total splicing length of the crystal rods that can be cut by a single dicing wire. L ;

[0051] S20. Based on the actual maximum processable ingot length of the slicing machine. D M Determine the minimum number of cuts. c And the planned splicing length of a single cut of an entire crystal rod. D ,in D ≤ D M , c × D M ≥ L ,c × D ≤ L ;

[0052] S30. Determine the actual splicing length of the entire crystal rod in a single cut. D n The value range of is (0.85). D ≤ D n ≤1.15 D )∩( D n ≤ D M );

[0053] S40. Based on the actual splicing length D n The range of values ​​is used to splice multiple segmented crystal rods into at least c The sum of the lengths of all the complete crystal rod segments ∑ D n ≤ L .

[0054] Specifically, step S10 calculates the total splicing length of the crystal rods that can be cut by a single roll of cutting wire. L include:

[0055] S11. Based on the total length of the single roll cutting line s The number of traces required for cutting a single wafer l Calculate the total number of wafers that a single dicing wire can cut. a , a = s / l ;

[0056] S12. According to the specified thickness value of a single wafer. m Calculate the total splicing length of the crystal rods that can be cut by a single dicing wire. L , L = a × m .

[0057] Among them, the total length of a single roll of cutting line s Given the number of traces required to cut a single wafer. l This is a known value, determined according to a pre-defined wafer fabrication process, representing the specified thickness of a single wafer. m = Grooved wheel pitch value - cutting line diameter. The grooved wheel pitch value is determined according to the pre-defined wafer processing technology, and the grooved wheel is also specially customized according to the wafer processing technology.

[0058] Step S20: Based on the actual maximum processable ingot length of the slicing machine DM Determine the minimum number of cuts. c And the planned splicing length of a single cut of an entire crystal rod. D ,include:

[0059] S21. If the total splicing length of the crystal rods is divisible by... D M Minimum number of cuts c = L / D M If the total splicing length of the crystal rods L Not divisible D M Minimum number of cuts c for L Divide by D M The integer value of the quotient is increased by one.

[0060] Minimum number of cuts c The value of must meet the following principle: Excess cutting lines are allowed, but the cutting lines cannot be used up prematurely before the entire crystal rod has been cut. For example, for a section that can be cut to a total splicing length... L Cutting lines up to 2000mm for a single crystal ingot, if using the actual maximum processable crystal ingot length. D M For a 600mm slicer, what is the minimum number of cuts required? c The value of is 4, which is the result of (2000÷600) rounded down and then incremented by one.

[0061] Further, in step S20, based on the actual maximum processable ingot length of the slicing machine... D M Determine the minimum number of cuts. c And the planned splicing length of a single cut of an entire crystal rod. D It also includes:

[0062] S22, Planned splicing length of a single cut of an entire crystal rod D = L / c .

[0063] Planned splicing length for single-cut crystal rod D A target value was set for the personnel to assemble the entire crystal rod segment, which is the length of the entire crystal rod assembled from the segmented crystal rods, i.e., the actual splicing length. D n The planned splicing length is close to that of a single cut of an entire crystal rod. D Ideally, the actual splicing length should be [spliced / adjusted]. D n The lower limit is 0.85. DThe upper limit is 1.15. D and D M The smaller one.

[0064] Further, in step S40, based on the actual splicing length... D n The range of values ​​is used to splice multiple segmented crystal rods into at least c The sum of the lengths of all the complete crystal rod segments ∑ D n ≤ L ,include:

[0065] S41, at least c In a complete crystal rod segment, the actual splicing length D n Compared with the actual maximum processable ingot length of the slicing machine D M The number of equal whole crystal rods is no more than 2.

[0066] This configuration minimizes the difference in length between multiple whole crystal rods when using a single dicing wire roll to cut them. Specifically, it reduces the variance / standard deviation of the multiple whole crystal rods as much as possible, making their lengths as close as possible to the planned splicing length from a single cut. D This avoids the occurrence of crystal rods that are too small in length. The smaller the length of a crystal rod, the more difficult and time-consuming the assembly process becomes, which is detrimental to improving wafer cutting efficiency.

[0067] For example, for a segment that can be cut and spliced ​​together... L Cutting lines up to 2000mm for a single crystal ingot, if using the actual maximum processable crystal ingot length. D M For a 550mm slicing machine, the actual allowable length of the entire crystal rod is 550mm. D 3 , D 4 , D 3 + D 4 =900mm, so we can match them up. D 3 , D 4When the length is 450mm, it can be assembled according to the target value of 450mm. Compared with assembling a whole 200mm crystal rod, the difficulty of assembling a whole 450mm crystal rod is significantly reduced. Moreover, the profit from cutting a whole 450mm crystal rod into wafers is significantly higher than that from cutting a whole 200mm crystal rod. Under the same depreciation cost and auxiliary material cost, a whole 450mm crystal rod can yield more wafers, and the cost per wafer is lower.

[0068] Further, in step S40, based on the actual splicing length... D n The range of values ​​is used to splice multiple segmented crystal rods into at least c The sum of the lengths of all the complete crystal rod segments ∑ D n ≤ L It also includes:

[0069] S42, in the n The length of the shortest segment of the crystal rod obtained from the ( )th splicing is not less than the length of the shortest segment of the crystal rod obtained from the ( )th splicing. n +1) lengths of the longest segment of the crystal rod obtained from splicing the entire crystal rod, where 1≤n≤( c -1);

[0070] S43, No. n The number of segmented crystal rods in the whole crystal rod obtained from the second splicing is not greater than that of the ()th splicing. n +1) The number of segmented crystal rods in the whole crystal rod obtained by splicing, where 1≤n≤( c -1).

[0071] Steps S42 and S43 reveal that when selecting segmented crystal rods to assemble a complete crystal rod, the principle of "longer first, then shorter, and similar lengths" is followed. That is, longer segmented crystal rods are selected first, followed by shorter ones. The shortest segmented crystal rod in the previous assembly is still longer than the longest segmented crystal rod in the subsequent assembly. Furthermore, as the available segmented crystal rod lengths gradually decrease, the number of segmented crystal rods required to assemble a complete crystal rod increases rather than decreases. From the early stage to the later stage, the lengths of the segmented crystal rods decrease, which also helps reduce the difficulty and time required to assemble the complete crystal rod.

[0072] This setup improves the overall quality and assembly efficiency of the entire crystal ingot. Generally, the longer the segmented crystal ingot, the fewer segments are needed to assemble the entire crystal ingot, the fewer times the segments need to be bonded, and the smaller the accumulated error during the bonding operation, resulting in higher overall crystal ingot quality. Following the principle of "longer segments first, then shorter segments, and segments of similar length" when assembling the entire crystal ingot reduces the overall number of segments included in the entire ingot. This allows the length of the entire crystal ingot assembled with fewer segments in the early stages to constitute a larger proportion of the total length. Conversely, if shorter segments are selected first, it is not conducive to increasing the proportion of the entire crystal ingot assembled with fewer segments, and the assembly difficulty and time consumption will increase in later stages as the length of the segments gradually increases.

[0073] Further, in step S40, based on the actual splicing length... D n The range of values ​​is used to splice multiple segmented crystal rods into at least c The sum of the lengths of all the complete crystal rod segments ∑ D n ≤ L It also includes:

[0074] S44, multiple segmented crystal rods spliced ​​together C n One complete crystal rod, 2 D M / 3≤ L / C n < D M .

[0075] The closer the length of the assembled and spliced ​​crystal ingot is to the optimal length, the higher the quality of the wafer obtained after slicing the ingot, but the cutting efficiency may decrease. Conversely, the longer the crystal ingot, the higher the crystal slicing efficiency, but the increased load on the slicing machine due to the longer ingot results in a slight decrease in the final wafer quality. It is worth noting that in some cases, the optimal length mentioned above is generally 1 / 2. D M Step S44 balances and considers both wafer quality and slicing efficiency, taking into account both wafer quality requirements and slicing efficiency requirements to a greater extent.

[0076] In some implementations, the total splice length that the cutting line can cut is... L The actual maximum processable crystal rod length of the slicing machine is 2000 mm. D M 600mm, minimum number of cuts c Given that all four conditions are known, what is the planned splicing length for a single cut of the entire crystal rod?D The actual splicing length is 400mm~500mm, and the length of the entire crystal rod cut in a single operation is [not specified]. D n The value range is [400, 600).

[0077] The technical features of the above-described embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0078] Those skilled in the art should recognize that the above embodiments are merely illustrative of the present invention and are not intended to limit the present invention. Any appropriate changes and variations made to the above embodiments within the essential spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A method for assembling crystal rods, used to determine the length of a single crystal rod assembled from multiple segmented crystal rods, characterized in that, include: Calculate the total splicing length of the crystal rods that can be cut by a single dicing wire. L ; Based on the actual maximum processable ingot length of the slicing machine D M Determine the minimum number of cuts. c And the planned splicing length of a single cut of an entire crystal rod. D ,in D = L / c , D ≤ D M , c × D M ≥ L , c × D ≤ L If the total splicing length of the crystal rods L Divisible D M Minimum number of cuts c = L / D M If the total splicing length of the crystal rods L Not divisible D M Minimum number of cuts c for L Divide by D M Increment the integer value of the quotient by one; Determine the actual splicing length of a single cut of a whole crystal rod. D n The value range is (0.85). D ≤ D n ≤1.15 D )∩( D n ≤ D M ); Based on the actual splicing length D n The range of values ​​is used to splice multiple segmented crystal rods into at least c The sum of the lengths of all the complete crystal rod segments ∑ D n ≤ L .

2. The method for aligning the length dimensions of crystal rods according to claim 1, characterized in that, Calculate the total splicing length of the crystal rods that can be cut by a single dicing wire. L ,include: Based on the total length of the single roll cutting line s The number of traces required for cutting a single wafer l Calculate the total number of wafers that a single dicing wire can cut. a , a = s / l ; According to the specified thickness value of a single wafer m Calculate the total splicing length of the crystal rods that can be cut by a single dicing wire. L , L = a × m .

3. The method for aligning the length dimensions of crystal rods according to claim 1, characterized in that, Based on the actual splicing length D n The range of values ​​is used to splice multiple segmented crystal rods into at least c The sum of the lengths of all the complete crystal rod segments ∑ D n ≤ L ,include: At least c In a complete crystal rod segment, the actual splicing length D n Compared with the actual maximum processable ingot length of the slicing machine D M The number of equal whole crystal rods is no more than 2.

4. The method for aligning the length dimensions of crystal rods according to claim 1, characterized in that, Based on the actual splicing length D n The range of values ​​is used to splice multiple segmented crystal rods into at least c The sum of the lengths of all the complete crystal rod segments ∑ D n ≤ L ,include: In the n The length of the shortest segment of the crystal rod obtained from the ( )th splicing is not less than the length of the shortest segment of the crystal rod obtained from the ( )th splicing. n +1) lengths of the longest segment of the crystal rod obtained from splicing the entire crystal rod, where 1≤n≤( c -1).

5. The method for aligning the length dimensions of crystal rods according to claim 4, characterized in that, Based on the actual splicing length D n The range of values ​​is used to splice multiple segmented crystal rods into at least c The sum of the lengths of all the complete crystal rod segments ∑ D n ≤ L ,include: No. n The number of segmented crystal rods in the whole crystal rod obtained from the second splicing is not greater than that of the ()th splicing. n +1) The number of segmented crystal rods in the whole crystal rod obtained by splicing, where 1≤n≤( c -1).

6. The method for aligning the length dimensions of crystal rods according to claim 1, characterized in that, The actual maximum processable ingot length of the slicing machine D M The minimum number of cuts is 600 mm. c The planned splicing length for a single cut of the entire crystal rod is 4. D It is 400mm~500mm.

7. The method for aligning the length dimensions of crystal rods according to claim 6, characterized in that, The total splicing length of the crystal rods that can be cut by the single-roll cutting wire. L The actual splicing length of the single-cut crystal rod is 2000 mm. D n The value range is [350, 550).