Silicon carbide ingot evaluation method and device

Abstract

The present invention provides a method and apparatus for evaluating silicon carbide ingots. The method comprises: obtaining a first chip and a second chip of a silicon carbide ingot; determining N first reference points on the first chip and obtaining an X-ray diffraction result for each first reference point; determining N second reference points corresponding to the first reference points on the second chip and obtaining an X-ray diffraction result for each second reference point; and evaluating the quality of the silicon carbide ingot based on the X-ray diffraction results of each first reference point and each second reference point.

Description

Technical Field

[0001] The present invention relates to a method and device for evaluating a crystal ingot, and in particular to a method and device for evaluating a silicon carbide crystal ingot. Background Art

[0002] In the prior art, during the processes of cutting, grinding, polishing, etc. of the silicon carbide ingot, the characteristics of the silicon carbide ingot (such as the stress remaining on the silicon carbide ingot) will have a decisive impact on the geometric quality of its subsequent processing.

[0003] Therefore, for those skilled in the art, if the characteristics of silicon carbide ingots can be known in advance, corresponding processing procedures can be adopted to avoid material waste. Summary of the Invention

[0004] In view of this, the present invention provides a method and apparatus for evaluating silicon carbide ingots, which can be used to solve the aforementioned technical problems.

[0005] The present invention provides a method for evaluating a silicon carbide ingot, comprising: obtaining a first chip and a second chip of the silicon carbide ingot; determining N first reference points on the first chip and obtaining an X-ray diffraction result of each first reference point, wherein N is a positive integer; determining N second reference points corresponding to the multiple first reference points on the second chip and obtaining an X-ray diffraction result of each second reference point; and evaluating the ingot quality of the silicon carbide ingot based on the X-ray diffraction results of each first reference point and the X-ray diffraction results of each second reference point.

[0006] The present invention provides a silicon carbide ingot evaluation device, comprising a storage circuit and a processor. The storage circuit stores program code. The processor is coupled to the storage circuit and accesses the program code to execute the following steps: obtaining a first chip and a second chip of a silicon carbide ingot; determining N first reference points on the first chip and obtaining an X-ray diffraction result for each first reference point, where N is a positive integer; determining N second reference points corresponding to the first reference points on the second chip and obtaining an X-ray diffraction result for each second reference point; and evaluating the quality of the silicon carbide ingot based on the X-ray diffraction results of each first reference point and each second reference point. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The accompanying drawings are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the present invention and together with the description serve to explain the principles of the present invention.

[0008] Figure 1 is a schematic diagram of a silicon carbide ingot evaluation device according to an embodiment of the present invention;

[0009] Figure 2is a flow chart of a method for evaluating silicon carbide ingots according to an embodiment of the present invention;

[0010] Figure 3A is a schematic diagram of a silicon carbide ingot according to an embodiment of the present invention;

[0011] Figure 3B is based on Figure 3A A schematic diagram of a first chip is shown;

[0012] Figure 3C is based on Figure 3A A schematic diagram of a second chip is shown;

[0013] Figure 4 is based on Figures 3A to 3C A schematic diagram of a first trend line and a second trend line is shown;

[0014] Figure 5 This is a diagram showing the relative relationship between the comprehensive index score and the curvature variation shown in Table 9. DETAILED DESCRIPTION

[0015] Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals are used in the drawings and the description to refer to the same or like parts.

[0016] Please refer to Figure 1 , which is a schematic diagram of a silicon carbide ingot evaluation device according to an embodiment of the present invention. Figure 1 In the embodiment, the silicon carbide ingot evaluation device 100 may include various computer devices and / or intelligent devices, but is not limited thereto.

[0017] like Figure 1 As shown, the silicon carbide ingot evaluation device 100 may include a storage circuit 102 and a processor 104. The storage circuit 102 may be, for example, any type of fixed or removable random access memory (RAM), read-only memory (ROM), flash memory, hard disk, or other similar device or a combination of these devices, and may be used to record multiple program codes or modules.

[0018] The processor 104 is coupled to the memory circuit 102 and can be a general-purpose processor, a special-purpose processor, a conventional processor, a digital signal processor, a plurality of microprocessors, one or more microprocessors combined with a digital signal processor core, a controller, a microcontroller, an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), any other type of integrated circuit, a state machine, an Advanced RISC Machine (ARM)-based processor, and the like.

[0019] In an embodiment of the present invention, the processor 104 may access the modules and program codes stored in the storage circuit 102 to implement the silicon carbide material evaluation method proposed in the present invention, the details of which are described below.

[0020] Please refer to Figure 2 , which is a flow chart of a method for evaluating silicon carbide ingots according to an embodiment of the present invention. The method of this embodiment can be Figure 1 The silicon carbide ingot evaluation device 100 is used to perform the following Figure 1 Description of components shown Figure 2 In addition, in order to make the concept of the present invention easier to understand, the following will be supplemented with Figures 3A to 3C To illustrate, Figure 3A is a schematic diagram of a silicon carbide ingot according to an embodiment of the present invention. Figure 3B is based on Figure 3A The first chip schematic is shown, and Figure 3C is based on Figure 3A A schematic diagram of a second chip is shown.

[0021] The silicon carbide ingot 300 includes a head end 301 region, a middle region 303 region, and a tail end 302 region. The head end 301 region and the tail end 302 region are located at opposite ends of the middle region 303. The sizes of the head end 301 region, the middle region 303 region, and the tail end 302 region can be divided according to needs, but the present invention is not limited to this. First, in step S210, a first chip 310 and a second chip 320 of the silicon carbide ingot 300 are obtained. In a preferred embodiment, the first chip 310 is, for example, the chip located in the head end (top) 301 region of the silicon carbide ingot 300, and the second chip 320 is, for example, the chip located in the tail end (bottom) 302 region of the silicon carbide ingot 300. In one embodiment, one or more chips can be cut from the head end (top) 301 region of the silicon carbide ingot 300, and one of them can be selected as the first chip 310, and one or more chips can be cut from the tail end (bottom) 302 region of the silicon carbide ingot 300, and one of them can be selected as the second chip 320, but it is not limited to this. In other embodiments, the first chip 310 and the second chip 320 can also be obtained from any position of the silicon carbide ingot 300, and the present invention is not limited to this.

[0022] Next, in step S220, the processor 104 may determine N first reference points on the first chip 310 and obtain X-ray diffraction results for each first reference point. In various embodiments, N is a positive integer not less than 5. For ease of illustration, the following assumes that N is 5, but the present invention is not limited thereto.

[0023] Please refer to Figure 3B For example, the processor 104 may determine five (i.e., N) first reference points P1-P5 on the first chip 310 and obtain X-ray diffraction results for each of the first reference points P1-P5. In some embodiments, the processor 104 may arbitrarily select N points on the first chip 310 as the first reference points P1-P5. In some embodiments, the first reference points P1-P5 selected by the processor 104 may be evenly distributed on the first chip 310. In this way, the first reference points P1-P5 may better represent the statistical characteristics of the quality of the first chip 310, but the present invention is not limited thereto.

[0024] In one embodiment, the first chip 310 may include a carbon surface 312 and a silicon surface 311 opposite to the carbon surface 312 , and the first reference points P1 - P5 may be located on the silicon surface 311 of the first chip 310 , for example, but is not limited thereto.

[0025] In some embodiments, the first chip 310 may have a center point (for example, the position of the first reference point P1), and the radius of the first chip 310 is r, wherein the distance between at least one of the first reference points P1~P5 and this center point may be between 0.5r and 0.9r, but is not limited thereto.

[0026] After determining the first reference points P1 to P5, the processor 104 may measure the full width at half maximum (FWHM) of the diffraction peaks of the first reference points P1 to P5 as the X-ray diffraction results of the first reference points P1 to P5, but the invention is not limited thereto. In some embodiments, the X-ray diffraction result of the i-th (1≤i≤N) first reference point among the first reference points P1 to P5 may be characterized as a i For example, the X-ray diffraction result of the first reference point P1 (i.e., the first first reference point) can be characterized as a1, the X-ray diffraction result of the first reference point P2 (i.e., the second first reference point) can be characterized as a2, the X-ray diffraction result of the first reference point P3 (i.e., the third first reference point) can be characterized as a3, the X-ray diffraction result of the first reference point P4 (i.e., the fourth first reference point) can be characterized as a4, and the X-ray diffraction result of the first reference point P5 (i.e., the fifth first reference point) can be characterized as a5.

[0027] Thereafter, in step S230 , the processor 104 may determine N second reference points corresponding to the plurality of first reference points P1 - P5 on the second chip 320 , and obtain an X-ray diffraction result of each second reference point.

[0028] Please refer to Figure 3C For example, the processor 104 may determine five (i.e., N) second reference points P1'-P5' on the second chip 320 and obtain X-ray diffraction results for each of the second reference points P1'-P5'. In some embodiments, the processor 104 may select N points on the second chip 320 that correspond to the first reference points P1-P5 as the second reference points P1'-P5'. In one embodiment, the second chip 320 may include a carbon surface 322 and a silicon surface 321, and the second reference points P1'-P5' may be located on the silicon surface 321 of the second chip 320, but the present invention is not limited thereto.

[0029] In one embodiment, the distribution positions of the first reference points P1-P5 on the first chip 310 may correspond one-to-one to the distribution positions of the second reference points P1'-P5' on the second chip 320, but the present invention is not limited thereto. In this way, the second reference points P1'-P5' can serve as a better comparison reference for the first reference points P1-P5.

[0030] After determining the second reference points P1'-P5', the processor 104 may measure the half-maximum width (FWHM) of the diffraction peaks of the second reference points P1'-P5' as the X-ray diffraction results of the second reference points P1'-P5', but is not limited thereto. In some embodiments, the X-ray diffraction result of the i-th second reference point among the second reference points P1'-P5' may be characterized as b i, where 1≤i≤N, but is not limited thereto. For example, the X-ray diffraction result of the second reference point P1' (i.e., the first second reference point) can be characterized as b1, the X-ray diffraction result of the second reference point P2' (i.e., the second second reference point) can be characterized as b2, the X-ray diffraction result of the second reference point P3' (i.e., the third second reference point) can be characterized as b3, the X-ray diffraction result of the second reference point P4' (i.e., the fourth second reference point) can be characterized as b4, and the X-ray diffraction result of the second reference point P5' (i.e., the fifth second reference point) can be characterized as b5.

[0031] Thereafter, in step S240 , the processor 104 may evaluate the ingot quality of the silicon carbide ingot 200 based on the X-ray diffraction results of the first reference points P1 - P5 and the X-ray diffraction results of the second reference points P1 ′ - P5 ′.

[0032] In some embodiments, the X-ray diffraction results of each first reference point P1~P5 can form a first trend line, and the X-ray diffraction results of each second reference point P1'~P5' can form a second trend line, and the processor 104 can be configured to: determine multiple cross-index values ​​and multiple reverse index values ​​of the first trend line and the second trend line based on the X-ray diffraction results of each first reference point P1~P5 and the X-ray diffraction results of each second reference point P1'~P5'; obtain the diffraction peak area of ​​each first reference point P1~P5 and the diffraction peak area of ​​each second reference point P1'~P5', and determine multiple diffraction peak area comparison results accordingly; determine the comprehensive index score of the silicon carbide ingot 300 as the ingot quality of the silicon carbide ingot 300 based on the multiple cross-index values, the multiple reverse index values ​​and the multiple diffraction peak area comparison results.

[0033] In an embodiment of the present invention, the X-ray diffraction results of the first reference points P1 - P5 and the X-ray diffraction results of the second reference points P1 ′ - P5 ′ can be measured to obtain values ​​as shown in Table 1 below.

[0034] First reference point X-ray diffraction results Second reference point X-ray diffraction results P1 <![CDATA[92.6 (i.e., a1)]]> P1’ <![CDATA[91.8 (i.e., b1)]]> P2 <![CDATA[96 (i.e., a2)]]> P2’ <![CDATA[95.1 (i.e., b2)]]> P3 <![CDATA[80.9 (i.e., a3)]]> P3’ <![CDATA[138.8 (i.e., b3)]]> P4 <![CDATA[116.8 (i.e., a4)]]> P4’ <![CDATA[91.2 (i.e., b4)]]> P5 <![CDATA[100.2 (i.e., a5)]]> P5’ <![CDATA[97.5 (i.e., b5)]]>

[0035] Table 1

[0036] Please refer to Figure 4 , which is based on Figures 3A to 3C Schematic diagram of the first trend line and the second trend line shown. Figure 4 , the first trend line 410 includes, for example, nodes 411 to 415 corresponding to the FWHMs of the first reference points P1 to P5, respectively. Furthermore, the second trend line 420 includes, for example, nodes 421 to 425 corresponding to the FWHMs of the second reference points P1' to P5', respectively.

[0037] Therefore, the processor 104 may determine a plurality of cross index values ​​and a plurality of reverse index values ​​of the first trend line 410 and the second trend line 420 based on the X-ray diffraction results of the first reference points P1 - P5 and the X-ray diffraction results of the second reference points P1 ′ - P5 ′.

[0038] In some embodiments, in the process of obtaining the multiple cross index values ​​and the multiple reverse index values, the processor 104 may determine multiple cross variations and multiple directional variations based on the X-ray diffraction results of each first reference point P1~P5 and the X-ray diffraction results of each second reference point P1'~P5'.

[0039] In one embodiment, the processor 104 may a i Subtract b i Based on the contents of Table 1, the crossover variances obtained by the processor 104 may be as shown in Table 2 below.

[0040] <![CDATA[a i ]]> <![CDATA[b i ]]> <![CDATA[Cross mutation amount (i.e., a i -b i )]]> <![CDATA[a1=92.6]]> <![CDATA[b1=91.8]]> 0.8 <![CDATA[a2=96]]> <![CDATA[b2=95.1]]> 0.9 <![CDATA[a3=80.9]]> <![CDATA[b3=138.8]]> -57.9 <![CDATA[a4=116.8]]> <![CDATA[b4=91.2]]> 25.6 <![CDATA[a5=100.2]]> <![CDATA[b5=97.5]]> 2.7

[0041] Table 2

[0042] After obtaining the plurality of crossover variances, the processor 104 may determine a plurality of crossover indicators based on the plurality of crossover variances.

[0043] In one embodiment, the processor 104 may be configured to: in response to determining that the sign of the j+1th crossover variance in the plurality of crossover variances is different from the sign of the jth crossover variance in the plurality of crossover variances, set the jth crossover indicator in the plurality of crossover indicators to a first value (e.g., 1); and in response to determining that the sign of the j+1th crossover variance is the same as the sign of the jth crossover variance, set the jth crossover indicator to a second value (e.g., 0), where 1≤j≤N-1. Based on the contents of Table 2, the crossover indicators obtained by the processor 104 may be as shown in Table 3 below.

[0044] <![CDATA[a i ]]> <![CDATA[b i ]]> Crossover variation Cross indicator <![CDATA[a1=92.6]]> <![CDATA[b1=91.8]]> 0.8 N / A <![CDATA[a2=96]]> <![CDATA[b2=95.1]]> 0.9 0 <![CDATA[a3=80.9]]> <![CDATA[b3=138.8]]> -57.9 1 <![CDATA[a4=116.8]]> <![CDATA[b4=91.2]]> 25.6 1 <![CDATA[a5=100.2]]> <![CDATA[b5=97.5]]> 2.7 0

[0045] Table 3

[0046] Specifically, when j is 1, since the second crossover variance (i.e., 0.9) is positive and the first crossover variance (i.e., 0.8) is also positive, the processor 104 may set the first crossover indicator to the second value (e.g., 0). Furthermore, when j is 2, since the third crossover variance (i.e., -57.9) is negative but the second crossover variance (i.e., 0.9) is positive, the processor 104 may set the second crossover indicator to the first value (e.g., 1). The principles for determining the remaining crossover indicators can be derived from the above teachings and are not further elaborated here.

[0047] In one embodiment, the plurality of directional variations include a plurality of first directional variations and a plurality of second directional variations, and the processor 104 may be configured to: j+1 Subtract a j To obtain the jth first direction variation among the plurality of first direction variations; and j+1 Subtract b j Based on the contents of Table 1, the directional variations obtained by the processor 104 may be as shown in Table 3 below.

[0048]

[0049] Table 4

[0050] After obtaining the plurality of directional variations, the processor 104 may determine a plurality of reverse indicators accordingly.

[0051] In one embodiment, the processor 104 may be configured to: in response to determining that the sign of the j-th first directional variation is different from the sign of the j-th second directional variation, set the j-th reverse indicator among the plurality of reverse indicators to a first value (e.g., 1); and in response to determining that the sign of the j-th first directional variation is the same as the sign of the j-th second directional variation, set the j-th reverse indicator to a second value (e.g., 0). Based on the contents of Table 4, the reverse indicators obtained by the processor 104 may be as shown in Table 5 below.

[0052] The first direction variation Second direction variation Reverse indicator 3.4 3.3 0 -15.1 43.7 1 35.9 -47.6 1 -16.6 6.3 1

[0053] Table 5

[0054] Specifically, when j is 1, since the first first-direction variance (i.e., 3.4) is positive and the first second-direction variance (i.e., 3.3) is also positive, the processor 104 may set the first reverse indicator to the second value (e.g., 0). Furthermore, when j is 2, since the second first-direction variance (i.e., -15.1) is negative but the second second-direction variance (i.e., 43.7) is positive, the processor 104 may set the second reverse indicator to the first value (e.g., 1). The principles for determining the remaining reverse indicators can be derived from the above teachings and are not further elaborated here.

[0055] Afterwards, the processor 104 may obtain the plurality of crossing index values ​​based on the plurality of crossing indicators and the plurality of directional variations.

[0056] In one embodiment, the processor 104 may be configured to: in response to determining that the jth crossing indicator among the plurality of crossing indicators indicates a first value (e.g., 1), use the larger of the absolute value of the jth first-directional variation and the absolute value of the jth second-directional variation as the jth crossing indicator value among the plurality of crossing index values; and in response to determining that the jth crossing indicator indicates a second value (e.g., 0), set the jth crossing indicator value to a null value. Based on the contents of Tables 3 and 4, the cross-indicator values ​​obtained by the processor 104 may be as shown in Table 6 below.

[0057] The first direction variation Second direction variation Cross indicator Cross-index value 3.4 3.3 0 0 -15.1 43.7 1 43.7 35.9 -47.6 1 47.6 -16.6 6.3 0 0

[0058] Table 6

[0059] Specifically, when j is 1, since the first cross indicator indicates the second value (i.e., 0), the processor 104 may set the first cross indicator value to a null value (represented by 0). When j is 2, since the second cross indicator indicates the first value (i.e., 1), the processor 104 may use the larger of the absolute value of the second first-direction variation (i.e., -15.1) and the absolute value of the second second-direction variation (i.e., 43.7) as the second cross indicator value (i.e., 43.7). The principles for determining the remaining cross indicator values ​​can be derived from the above teachings and are not further elaborated here.

[0060] Afterwards, the processor 104 may obtain the plurality of reverse index values ​​based on the plurality of reverse indicators and the plurality of directional variations.

[0061] In one embodiment, the processor 104 may be configured to: in response to determining that the jth reverse indicator among the plurality of reverse indicators indicates a first value, sum the absolute value of the jth first-directional variation and the absolute value of the jth second-directional variation as the jth reverse indicator value among the plurality of reverse index values; and in response to determining that the jth reverse indicator indicates a second value, set the jth reverse indicator value to a null value. Based on the contents of Tables 4 and 5, the reverse indicator values ​​obtained by the processor 104 may be as shown in Table 7 below.

[0062] The first direction variation Second direction variation Reverse indicator Reverse indicator value 3.4 3.3 0 0 -15.1 43.7 1 58.8 35.9 -47.6 1 83.5 -16.6 6.3 1 22.9

[0063] Table 7

[0064] Specifically, when j is 1, since the first reverse indicator indicates the second value (i.e., 0), the processor 104 may set the first reverse indicator value to a null value (represented by 0). When j is 2, since the second reverse indicator indicates the first value (i.e., 1), the processor 104 may sum the absolute value of the second first-direction variation (i.e., -15.1) and the absolute value of the second second-direction variation (i.e., 43.7) as the second reverse indicator value (i.e., 58.8). The principles for determining the remaining reverse indicator values ​​can be derived from the above teachings and are not further elaborated here.

[0065] In one embodiment, after obtaining the multiple cross index values ​​and the multiple reverse index values, the processor 104 may obtain the diffraction peak area of ​​each first reference point P1-P5 and the diffraction peak area of ​​each second reference point P1'-P5', and determine multiple diffraction peak area comparison results accordingly.

[0066] In one embodiment, the processor 104 may be configured to: in response to determining that the diffraction peak area of ​​the i-th first reference point among the first reference points P1~P5 is greater than the diffraction peak area of ​​the i-th second reference point among the second reference points P1'~P5', determine that the i-th diffraction peak area comparison result among the multiple diffraction peak area comparison results is a first value (for example, 1); in response to determining that the diffraction peak area of ​​the i-th first reference point P1~P5 is not greater than the diffraction peak area of ​​the i-th second reference point P1'~P5', determine that the i-th diffraction peak area comparison result is a second value (for example, 0).

[0067] In an embodiment of the present invention, it is assumed that the diffraction peak area of ​​the first reference point P1 is greater than the diffraction peak area of ​​the second reference point P1', the diffraction peak area of ​​the first reference point P2 is greater than the diffraction peak area of ​​the second reference point P2', the diffraction peak area of ​​the first reference point P3 is greater than the diffraction peak area of ​​the second reference point P3', the diffraction peak area of ​​the first reference point P4 is greater than the diffraction peak area of ​​the second reference point P4', and the diffraction peak area of ​​the first reference point P5 is greater than the diffraction peak area of ​​the second reference point P5'. In this case, the diffraction peak area comparison results obtained by the processor 104 can all be the first value (e.g., 1), but are not limited to this.

[0068] Subsequently, when the processor 104 determines a comprehensive index score for the silicon carbide ingot based on the multiple cross-index values, the multiple inverse index values, and the multiple diffraction peak area comparison results, the processor 104 may be configured to: in response to determining that the i-th diffraction peak area comparison result indicates a first value, maintain the i-th cross-index value among the multiple cross-index values ​​and the i-th inverse index value among the multiple inverse index values; in response to determining that the i-th diffraction peak area comparison result indicates a second value, set the i-th cross-index value and the i-th inverse index value to a null value; and sum the multiple cross-index values ​​and the multiple inverse index values ​​to form a comprehensive index score for the silicon carbide ingot 300. Based on the contents of Tables 6 and 7, the comprehensive index score obtained by the processor 104 may be as shown in Table 8 below.

[0069]

[0070] Table 8

[0071] Specifically, when i is 1, since the first diffraction peak area comparison result indicates a first value (e.g., 1), the processor 104 may maintain (i.e., not change) the first cross-index value and the first reverse index value. Similarly, since the second through fourth diffraction peak area comparison results all indicate a first value (e.g., 1), the processor 104 may maintain the second through fourth cross-index values ​​and the second through fourth reverse index values. Subsequently, the processor 104 may sum the cross-index values ​​and reverse index values ​​in Table 8 to obtain a comprehensive index score for the silicon carbide ingot 300 (i.e., 256.5).

[0072] In other embodiments, assuming the second diffraction peak area comparison result indicates a second value (e.g., 0), the processor 104 may set both the second crossover index value and the second reverse index value to null values ​​(which may be represented by 0), but the present invention is not limited thereto. In this case, the resulting composite index score for the silicon carbide ingot 300 would be 154 (i.e., 47.6 + 83.5 + 22.9).

[0073] Based on the comprehensive index score of the silicon carbide ingot 300 , the processor 104 can accordingly know the ingot quality of the silicon carbide ingot 300 .

[0074] Specifically, assuming a total of eight silicon carbide ingots C1-C8 are considered, after each of them has been processed, the bow variation of each silicon carbide ingot C1-C8 can be measured. Furthermore, the processor 104 can calculate the comprehensive index score for each of the silicon carbide ingots C1-C8 according to the above teachings.

[0075] In one embodiment, the curvature variation and comprehensive index score of each silicon carbide ingot C1-C8 can be shown in Table 9 below, and the related trend can be shown in Figure 5 middle.

[0076] Silicon carbide ingot Comprehensive indicator score Curvature variation C1 256.5 144 C2 235.8 98 C3 122.4 87 C4 136 117 C5 58 107 C6 0 16 C7 0 18 C8 11 8.3

[0077] Table 9

[0078] Generally speaking, if the curvature variation of a silicon carbide ingot after processing is less than 20μm, it can be considered that the quality of the ingot is good. Figure 5 It can be seen that for silicon carbide ingots C6 to C8 whose comprehensive index scores are lower than a certain score threshold, for example 25, but the present invention is not limited to this, their corresponding curvature variations are all below 20μm. Therefore, it can be said that silicon carbide ingots C6 to C8 have good ingot quality.

[0079] Based on this principle, for a silicon carbide ingot of unknown ingot quality, if its estimated comprehensive index score is lower than the aforementioned score threshold (e.g., 25), it can be inferred that the silicon carbide ingot is likely to have good ingot quality. Conversely, if the comprehensive index score of the silicon carbide ingot is higher than the aforementioned score threshold (e.g., 25), it can be inferred that the silicon carbide ingot is likely to have poor ingot quality.

[0080] In other words, through the method proposed in the present invention, the quality of the silicon carbide ingot 300 can be estimated based on the comprehensive index score of the silicon carbide ingot 300 without actually processing the silicon carbide ingot 300, and then appropriate treatment / processing can be taken on the silicon carbide ingot 300.

[0081] In summary, the present invention allows for the identification of multiple corresponding first and second reference points on the first and second chips of a silicon carbide ingot, and for the estimation of the silicon carbide ingot's quality based on the X-ray diffraction results of each first and second reference point. This allows for the estimation of the silicon carbide ingot's quality without actually processing the ingot, allowing for appropriate handling / processing of the ingot.

[0082] 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 above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above 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 method for evaluating silicon carbide ingots, characterized in that: include: Obtaining a first chip and a second chip of silicon carbide ingot; Determine N first reference points on the first chip and obtain X-ray diffraction results of each of the first reference points, where N is a positive integer; Determining N second reference points on the second chip corresponding to the N first reference points, and obtaining an X-ray diffraction result of each of the second reference points, wherein the X-ray diffraction result of each of the first reference points forms a first trend line, and the X-ray diffraction result of each of the second reference points forms a second trend line; as well as Evaluating the quality of the silicon carbide ingot based on the X-ray diffraction results of each first reference point and the X-ray diffraction results of each second reference point includes: Determining a plurality of crossover index values ​​and a plurality of reverse index values ​​of the first trend line and the second trend line based on the X-ray diffraction results of each of the first reference points and the X-ray diffraction results of each of the second reference points; obtaining the diffraction peak area of ​​each of the first reference points and the diffraction peak area of ​​each of the second reference points, and determining a plurality of diffraction peak area comparison results accordingly; Based on the comparison results of the multiple cross-index values, the multiple reverse index values ​​and the multiple diffraction peak areas, a comprehensive index score of the silicon carbide ingot is determined as the ingot quality of the silicon carbide ingot. 2 . The method according to claim 1 , wherein the first chip is a head-end chip of the silicon carbide ingot, and the second chip is a tail-end chip of the silicon carbide ingot.

3. The method according to claim 1, wherein the X-ray diffraction result of each first reference point is the half-maximum width of the diffraction peak of each first reference point, and the X-ray diffraction result of each second reference point is the half-maximum width of the diffraction peak of each second reference point.

4. The method according to claim 1 , wherein the step of determining the plurality of crossover index values ​​and the plurality of reverse index values ​​of the first trend line and the second trend line based on the X-ray diffraction results of each first reference point and the X-ray diffraction results of each second reference point comprises: determining a plurality of cross-variances and a plurality of directional variations based on the X-ray diffraction results of each of the first reference points and the X-ray diffraction results of each of the second reference points; determining a plurality of crossover indicators based on the plurality of crossover variances; determining a plurality of reverse indicators based on the plurality of directional variances; Obtaining the plurality of cross index values ​​based on the plurality of cross indicators and the plurality of directional variations; The plurality of reverse index values ​​are obtained based on the plurality of reverse indicators and the plurality of directional variations.

5. The method according to claim 4, wherein the X-ray diffraction result of the i-th first reference point among the N first reference points is characterized by , the X-ray diffraction result of the i-th second reference point among the plurality of second reference points is characterized as , and the step of determining the plurality of crossover variations based on the X-ray diffraction results of each of the first reference points and the X-ray diffraction results of each of the second reference points includes: by minus To obtain the i-th crossover variance among the multiple crossover variances, where .

6. The method according to claim 5, wherein the step of determining the plurality of crossing indicators based on the plurality of crossing variances comprises: In response to determining that the sign of the j+1th crossover variance in the plurality of crossover variances is different from the sign of the jth crossover variance in the plurality of crossover variances, setting the jth crossover indicator in the plurality of crossover indicators to a first value; and In response to determining that the sign of the j+1th crossover variance is the same as the sign of the jth crossover variance, setting the jth crossover indicator to a second value, wherein .

7. The method according to claim 4, wherein the plurality of directional variations include a plurality of first directional variations and a plurality of second directional variations, and the X-ray diffraction result of the j-th first reference point among the N first reference points is characterized as , the X-ray diffraction result of the j-th second reference point among the plurality of second reference points is characterized as , and the step of determining the plurality of directional variations based on the X-ray diffraction results of each of the first reference points and the X-ray diffraction results of each of the second reference points includes: by minus to obtain the jth first direction variation among the plurality of first direction variations; and by minus To obtain the jth second direction variation among the plurality of second direction variations, wherein .

8. The method according to claim 7, wherein the step of determining the plurality of reverse indicators based on the plurality of directional variations comprises: In response to determining that the sign of the j-th first direction variation is different from the sign of the j-th second direction variation, setting the j-th reverse direction indicator of the plurality of reverse direction indicators to a first value; as well as In response to determining that the sign of the j-th first direction variation is the same as the sign of the j-th second direction variation, the j-th reverse indicator is set to a second value.

9. The method according to claim 7, wherein the step of obtaining the plurality of cross index values ​​based on the plurality of cross indicators and the plurality of directional variations comprises: In response to determining that the j-th crossing indicator among the plurality of crossing indicators indicates a first value, using a larger absolute value of the j-th first-directional variation and an absolute value of the j-th second-directional variation as a j-th crossing index value among the plurality of crossing index values; In response to determining that the j-th crossing indicator indicates a second value, the j-th crossing indicator value is set to a null value.

10. The method according to claim 7, wherein the step of obtaining the plurality of reverse index values ​​based on the plurality of reverse indicators and the plurality of directional variations comprises: In response to determining that the jth reverse indicator among the plurality of reverse indicators indicates a first value, summing an absolute value of the jth first direction variation and an absolute value of the jth second direction variation as a jth reverse indicator value among the plurality of reverse indicator values; In response to determining that the jth reverse indicator indicates a second value, the jth reverse indicator value is set to a null value.

11. The method according to claim 1 , wherein the step of determining the comparison result of the plurality of diffraction peak areas comprises: In response to determining that the diffraction peak area of ​​the i-th first reference point among the N first reference points is greater than the diffraction peak area of ​​the i-th second reference point among the plurality of second reference points, determining that the i-th diffraction peak area comparison result among the plurality of diffraction peak area comparison results is a first value; In response to determining that the diffraction peak area of ​​the i-th first reference point is not greater than the diffraction peak area of ​​the i-th second reference point, determining that the i-th diffraction peak area comparison result is a second value.

12. The method according to claim 11 , wherein the step of determining the comprehensive index score of the silicon carbide ingot based on the comparison results of the plurality of cross-index values, the plurality of reverse index values, and the plurality of diffraction peak areas comprises: In response to determining that the i-th diffraction peak area comparison result indicates the first value, maintaining the i-th cross-index value among the plurality of cross-index values ​​and the i-th reverse index value among the plurality of reverse index values; In response to determining that the i-th diffraction peak area comparison result indicates the second value, setting the i-th cross-index value and the i-th reverse index value to null values; The multiple cross-index values ​​and the multiple reverse index values ​​are summed up to obtain the comprehensive index score of the silicon carbide ingot. 13 . The method according to claim 1 , wherein the first chip and the second chip respectively include a carbon surface and a silicon surface, the N first reference points are located on the silicon surface of the first chip, and the plurality of second reference points are located on the silicon surface of the second chip. 14 . The method according to claim 1 , wherein positions of the N first reference points on the first chip correspond to positions of the plurality of second reference points on the second chip. 15 . The method according to claim 1 , wherein the N first reference points are evenly distributed on the first chip, and the plurality of second reference points are evenly distributed on the second chip. 16 . The method according to claim 1 , wherein the first chip has a center point, and a radius of the first chip is r, wherein a distance between at least one of the N first reference points and the center point is between 0.5r and 0.9r.

17. A silicon carbide ingot evaluation device, characterized in that: include: a storage circuit for storing program codes; as well as a processor, coupled to the storage circuit and accessing the program code to execute: Obtaining a first chip and a second chip of silicon carbide ingot; Determine N first reference points on the first chip and obtain X-ray diffraction results of each of the first reference points, where N is a positive integer; Determining N second reference points on the second chip corresponding to the N first reference points, and obtaining an X-ray diffraction result of each of the second reference points, wherein the X-ray diffraction result of each of the first reference points forms a first trend line, and the X-ray diffraction result of each of the second reference points forms a second trend line; as well as Evaluating the quality of the silicon carbide ingot based on the X-ray diffraction results of each first reference point and the X-ray diffraction results of each second reference point includes: Determining a plurality of crossover index values ​​and a plurality of reverse index values ​​of the first trend line and the second trend line based on the X-ray diffraction results of each of the first reference points and the X-ray diffraction results of each of the second reference points; obtaining the diffraction peak area of ​​each of the first reference points and the diffraction peak area of ​​each of the second reference points, and determining a plurality of diffraction peak area comparison results accordingly; Based on the comparison results of the multiple cross-index values, the multiple reverse index values ​​and the multiple diffraction peak areas, a comprehensive index score of the silicon carbide ingot is determined as the ingot quality of the silicon carbide ingot.

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