KR20160014317A - A method of measuring a demage depth of a wafer - Google Patents

Abstract

The embodiment is characterized by the steps of obtaining a first swing curve for a wafer obtained by using an X-ray diffraction apparatus, setting a range of an X-ray incidence angle having an intensity higher than a reference level in the first swing curve, Calculating an interplanar distance to the line incident angle, calculating a strain value of the wafer using the calculated interplanar distance, and extracting sampled strain values based on the calculated strain value, Ray diffraction beam corresponding to the intensity of the X-ray diffraction beam corresponding to the X-ray diffraction beam, the range of the set X-ray incidence angle, the calculated inter-surface distance, the sampled strain values, Acquiring a second oscillation curve based on the thickness of the X-ray, a range of the X-ray incidence angle, the inter-surface distance, Matching the second oscillation curve with the first oscillation curve by varying at least one of the strain values or the modeled thickness, and calculating a damage depth of the wafer based on the matched result .

Description

FIELD OF THE INVENTION [0001] The present invention relates to a method of measuring a damage depth of a wafer,

An embodiment relates to a method for measuring the depth of mechanical damage of a wafer.

Generally, the wafer fabrication process may include a mechanical surface treatment process such as ingot grinding, ingot slicing, or lapping.

Such a mechanical surface treatment process may cause mechanical damage to the wafer surface. Such mechanical damage can be eliminated as the wafer is polished or etched by a post-process such as polishing, etching, or the like.

Depending on the depth of the mechanical damage, the amount of wafer removed in the post-process can be determined. To do this, measurements must be made to determine the depth of mechanical damage.

Methods for measuring mechanical damage may include a method using etching and polishing, a method using an x-ray diffractor, a method using Raman spectroscopy, or a method using photoluminescence.

However, a method using etching and polishing is a breaking method, and excessive time may be required for polishing and heat treatment. In addition, the method using the X-ray diffractometer can judge only the degree of damage and the degree of damage qualitatively. Also, the method using Raman spectroscopy and the method using photoluminescence can not measure the depth of damage.

The embodiment provides a method for accurately measuring the mechanical damage depth of a wafer using a non-destructive method.

A method for measuring the depth of damage of a wafer according to an embodiment includes obtaining a first swing curve for a wafer obtained using an X-ray diffraction apparatus; The range of the X-ray incidence angle having the intensity higher than the reference level in the first swing curve is set, the inter-plane distance to the set X-ray incidence angle is calculated, and the strain value of the wafer is calculated using the calculated inter- Extracting sampled strain values based on the calculated strain values; Modeling a thickness of the wafer based on the degree of damage of the wafer based on the intensity of the X-ray diffraction beam corresponding to the sampled strain values; Obtaining a second oscillation curve based on the set X-ray incidence angle range, the calculated inter-surface distance, the sampled strain values, and the modeled thickness; Matching the second oscillation curve with the first oscillation curve by varying at least one of the range of the X-ray incidence angle, the inter-surface distance, or the sampled strain values, or the modeled thickness; And calculating a damage depth of the wafer based on the matched result.

Wherein the acquiring of the first shaking curve comprises: setting points at which to evaluate crystallinity in the wafer; Obtaining X-ray oscillation curves for the points of the set wafer; And comparing the full width at half maximum (FWHM) of the X-ray oscillation curves of the points of the wafer set, and obtaining the first oscillation curve according to the comparison result.

The first swing curve having the largest half-width of the X-ray swing curve can be selected.

The intensity of the diffracted beam in which the first oscillation curve is saturated can be set to the reference level.

Wherein the strain value of the wafer is a ratio of a distance between a subtracting surface and a reference plane, and the reference plane distance is an interplane distance corresponding to a value of the intensity of the diffracted beam having the largest intensity in the first swinging curve, And the distance between the reference plane and the reference plane.

The extracting of the sampled strain values may extract the sampled strain values based on a highest value among the calculated strain values.

Modeling the thickness according to the degree of damage of the wafer includes obtaining the intensity of the X-ray diffraction beam corresponding to each of the sampled strain values; And modeling the thickness according to the degree of damage of the wafer in proportion to the intensity of the obtained X-ray diffraction beam.

Modeling the thickness of the wafer according to the degree of damage includes: dividing the wafer into a plurality of sections in the depth direction according to the degree of damage; Obtaining an intensity of an X-ray diffraction beam corresponding to each of the sampled strain values; And setting a thickness of each of the plurality of intervals in proportion to the intensity of the obtained X-ray diffraction beam.

Wherein the wafer is a semiconductor wafer obtained by performing a slicing process on a monocrystalline ingot in the step of acquiring the first swing curve, or the lapping process, the grinding process, or the polishing process on the surface of the semiconductor wafer Or may be a wafer that has performed at least one.

The matching step may match the second swinging curve with the first swinging curve by adjusting a thickness set for each of the plurality of sections.

The step of calculating the depth of damage of the wafer may sum all the adjusted thicknesses of the plurality of sections and calculate the summed result as the depth of damage of the wafer.

The points at which the crystallinity is to be evaluated may be a midpoint of the wafer, an edge point, and a point that is one-half of the radius of the wafer.

The points to be evaluated for crystallinity may be spaced apart from one another in the form of radiation.

Embodiments can accurately measure the mechanical damage depth of a wafer using a non-destructive method.

1 is a flow chart illustrating a method for detecting mechanical damage of a wafer according to an embodiment.
Fig. 2 shows an embodiment of the wafer crystallinity evaluation method.
Figure 3 shows X-ray oscillation curves for predetermined points of the wafer.
FIG. 4 shows an embodiment of the modeling step shown in FIG.
Fig. 5 shows an embodiment of the first swing curve for explaining the modeling step shown in Fig.
6 is a diagram for explaining modeling of degree of mechanical damage of the wafer shown in FIG.
Figs. 7A to 7D show the process of matching the measured value of the first oscillation curve according to the embodiment, and the second oscillation curve according to the simulated result.
8 is a graph showing the depth of damage measured according to the method using etch and polishing and the method according to the embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. In the description of the embodiments, it is to be understood that each layer (film), region, pattern or structure may be referred to as being "on" or "under" a substrate, each layer It is to be understood that the terms " on "and " under" include both " directly "or" indirectly " do. In addition, the criteria for the top / bottom or bottom / bottom of each layer are described with reference to the drawings.

In the drawings, dimensions are exaggerated, omitted, or schematically illustrated for convenience and clarity of illustration. Also, the size of each component does not entirely reflect the actual size. The same reference numerals denote the same elements throughout the description of the drawings. Hereinafter, a method of detecting mechanical damage of a wafer according to an embodiment will be described with reference to the accompanying drawings.

1 is a flow chart illustrating a method for detecting mechanical damage of a wafer according to an embodiment.

Referring to FIG. 1, a wafer for detecting mechanical damage is prepared (S110).

The wafer prepared at this time may be a semiconductor wafer obtained by growing a single crystal ingot, performing an ingot grinding process, a cropping process, and a slicing process on the grown single crystal ingot. For example, the semiconductor wafer may include other monocrystalline wafers such as sapphire.

Alternatively, the prepared wafer may be subjected to at least one of a lapping process, a grinding process, an etching process, and a polishing process with respect to the surface of the semiconductor wafer.

Next, a first swing curve is obtained for the prepared wafer using an X-ray diffraction apparatus (S120).

For example, it is possible to perform a crystallinity evaluation on a prepared wafer and acquire a first shaking curve according to the crystallization evaluation result.

 For example, it is possible to perform a deterministic evaluation on preset points at different positions of a prepared wafer, to select a point having crystallinity for the most thermal in accordance with the evaluation result, The X-ray oscillation curve for the point having the first oscillation curve can be selected as the first oscillation curve.

Fig. 2 shows an embodiment of the wafer crystallinity evaluation method.

Referring to FIG. 2, first, points of a wafer to be evaluated for crystallinity are set (S210).

For example, predetermined points of the wafer for which crystallinity is to be evaluated may be a center point, an edge point, and a point that is one-half of the wafer radius, but the positions and the number of predetermined points are limited thereto It is not. In other embodiments, predetermined points may be spaced apart from one another in the form of radiation.

Next, an X-ray rocking curve is obtained for each of predetermined points using an X-ray diffraction apparatus (S220).

When an X-ray is transmitted through a certain crystal, the diffraction angle of the X-ray in a specific plane of crystal can be determined by Bragg's law of Bragg. The intensity of the X-ray diffraction beam can be represented by a single line if the crystal is completely intact.

On the other hand, if there is a defect in the crystal, for example, a point, a line, a surface, or a volumetric defect, the intensity of the X-ray diffraction beam shows a curve of a gaussian distribution instead of a single line. Can be referred to as an X-ray rocking curve.

Figure 3 shows X-ray oscillation curves for predetermined points of the wafer.

The x-axis represents the incident angle of the X-ray, and the y-axis represents the intensity of the X-ray diffraction beam. g1 denotes an X-ray oscillation curve for the center point of the wafer (hereinafter referred to as "first point"), g2 denotes an X-ray oscillation And g3 represents an X-ray oscillation curve for an edge point (hereinafter referred to as "third point") of the wafer.

Referring to FIG. 3, it can be seen that the X-ray oscillation curves g1, g2 and g3 for the first to third points are Gaussian, and that crystal defects exist in each of the first to third points Able to know.

Next, by comparing the full width at half maximum (FWHM) of the X-ray fluctuation curves g1, g2 and g3 of the preset points, it is possible to determine whether the crystallinity is the most heat- (S230). The half-value width refers to the width between values that are half the maximum intensity value in the swing curve.

The fact that the crystallinity is good means that there is almost no defect, and the fact that there are many mechanical damages on the surface of the wafer means that there are many defects on the wafer surface due to the physical force, The larger the number, the more defects can be present.

The crystalline heat spread for predefined points of the wafer can be proportional to the half-width of predefined points of the wafer.

Referring to the swing curves g1, g2 and g3 for the predetermined points shown in FIG. 3, it can be seen that the full width at half maximum of the swing curve g1 with respect to the first point of the wafer is the largest, It can be determined that the crystallinity of the first point is the weakest, and the first point of the wafer can be selected as the point for the most heat.

Next, based on the first swing curve, the thickness according to the degree of damage of the wafer in the depth direction of the wafer is modeled (S130).

Fig. 4 shows an embodiment of the modeling step S130 shown in Fig. 1, and Fig. 5 shows an embodiment of the first swing curve for explaining the modeling step S130 shown in Fig.

Referring to FIGS. 4 and 5, a reference level 501 for the first swing curve is set (S310). The first swing curve shown in FIG. 5 may be a swing curve with respect to a point at which the crystallinity selected in step S120 is the most heat, but the present invention is not limited thereto, and any one of the swing curves Lt; / RTI >

When XRD is measured, if the incident angle, which is the range of the x-axis of the first oscillation curve, is sufficiently large, the intensity of the diffracted beam in which the first oscillation curve saturates is set to a reference level or a background level have. This is because the intensity or base level of the diffraction beam of the first swing curve in the XRD measurement is determined by XRD measurement conditions such as power, slit size, X-ray tube lifetime tube lifetime, sample state, and the like.

Here, the reference level can be assumed to be the noise of the measurement state, and it is necessary to set the reference level in saturation. In theory, the reference level can be measured, although the intensity should be zero except at the point where the peak of the intensity appears because the Bragg diffraction condition is not satisfied.

Next, a range? L to? R of the X-ray incidence angle? Having an intensity higher than the reference level 501 in the X-ray oscillation curve is set (S320). The range? L to? R of the X-ray incidence angle? Set at this time can be determined according to the type of the wafer, the surface of the wafer, or the crystal state.

For example, in the case of a silicon wafer, the processed surface of the wafer may be a (100) plane, and since the diffraction does not occur on the (100) plane due to the X-ray diffraction structure, And the oscillation curve by the X-ray diffraction method can be measured on the (400) plane where the diffraction occurs. As described above, the crystal plane in which no diffraction occurs can be set as the reference plane.

For example, the angle of the X-ray detector may be fixed, and the intensity of the X-ray may be measured while varying the incident angle of the X-ray incident on the (400) plane. The range? L to? R of the X-ray incidence angle? May be substantially in the range of about 33.6 ° to 35.0 °.

However, when the processing surface of the wafer is changed, the range of the X-ray incidence angle? May vary. For example, in the case of (111) wafers or (110) wafers, the range of the X-ray incidence angle? May be different from that of silicon wafers because the crystal faces for measuring X-ray diffraction are different. Further, the range of the X-ray incidence angle? Can be changed when a wafer such as sapphire is compared with a silicon wafer.

The (100) wafer may refer to a wafer having an index of (100) on the front side or back side of the wafer, and the (111) wafer and the (110) 111, and 110, respectively. (100) plane may mean a crystal plane of silicon having a surface index of (100). Here, processing may mean slicing of the ingot, and may include lapping, grinding, polishing, etching, etc., in addition to slicing.

Generally, a silicon wafer can be sliced in a direction that is inclined by an off-angle from the (100) plane, rather than being accurately sliced to a reference plane, e.g., a (100) plane. Here, the specific angle can be determined by the customer's request.

Hereinafter, a wafer having a machined surface coinciding with a reference surface is referred to as a first wafer, and a wafer having a machined surface inclined at a specific angle from a reference surface is referred to as a second wafer.

The angle at which the peak value of the oscillation curve with respect to the first wafer appears may coincide with the angle at which the peak value of the oscillation curve with respect to the reference surface appears (hereinafter referred to as "first angle").

In the case of the reference plane, for example, the (400) plane of silicon, the interplanar distance and the wavelength of the X-ray are determined, so that the angle at which the peak value appears (for example, 34.566 °) can be obtained by Bragg diffraction conditions.

On the other hand, the angle at which the peak value of the oscillation curve with respect to the second wafer appears (hereinafter referred to as "second angle") may not match the angle at which the peak value of the oscillation curve with respect to the reference surface appears, have.

Therefore, for the second wafer, the correction of the swing curve may be necessary, and for the second wafer, the range of the X-ray incidence angle [theta] having the intensity higher than the reference level 501 may be And a subsequent procedure can also be performed based on the calibrated swing curve.

That is, the angle of the swing curve with respect to the second wafer can be corrected by the difference between the first angle and the second angle. For example, the swing curve for the second wafer can be moved in parallel to the X-axis direction by the difference between the first angle and the second angle.

Next, the interplanar distance d with respect to the range of the set X-ray incidence angle [theta] ([theta] L to [theta] R) is calculated (S330) using Bragg's law of? = 2dsin ?.

Where the inter-surface distance d may be the distance between the reference planes of the wafer.

For example, in the case of a silicon wafer, the interplanar distance d may mean the distance between (400) planes. That is, the interplanar distance between (400) planes deformed by damage due to mechanical machining.

The strain values of the wafers in the range of? L to? R of the X-ray incidence angle? Are calculated using the calculated inter-surface distance d (S340). Strain can be a ratio of how the interplanar distance d changed by some physical or mechanical factor compared to the reference interplanar distance d0.

For example, the strain value of the wafer may be a ratio (d1 / d0) of the distance d1 between the subtracting planes to the reference plane d0.

The reference inter-surface distance d0 may be the distance between the reference planes of the wafer.

The reference inter-surface distance d0 may be an inter-surface distance corresponding to the largest value of the intensity of the diffracted beam in the first swing curve. For example, the reference inter-surface distance d0 may be an inter-surface distance at a position where the intensity is the largest in the first swing curve.

For example, the reference inter-surface distance d0 to the silicon (400) plane may be 1.3577 angstroms (A).

The subtracted distance d1 may be the difference (d-d0) between the inter-surface distance d calculated in step S330 and the reference inter-surface distance d0.

Next, the strain values calculated corresponding to the range (? L to? R) of the X-ray incidence angle (?) Are sampled, and the sampled strain values are extracted (S350).

For example, the sampled strain values can be extracted based on the highest value among the calculated strain values. A sample of strain values can be extracted by decreasing the maximum value among the calculated strain values by a constant value.

For example, the difference in sampled strain values may be between 50 ppm and 150 ppm, but is not limited thereto. ppm stands for parts-per-million, which means 10 ^-6 .

For example, assuming that the largest value of the calculated strain is 1000 ppm, samples (e.g., 1000 ppm, 900 ppm, 800 ppm, 700 ppm, etc.) can be extracted while reducing the strain value by 100 ppm.

The thickness according to the degree of mechanical damage of the wafer can then be modeled based on the intensity of the X-ray diffraction beam corresponding to each of the extracted sampled strain values (S360).

The interplanar distance d from the extracted strain values can be calculated and the incident angle? Of the X-ray corresponding to the inter-surface distance d calculated using the Bragg diffraction condition can be calculated, The intensity of the X-ray diffraction beam corresponding to the X-ray incidence angle [theta] calculated by using the curve can be obtained. The thickness according to the degree of mechanical damage of the wafer can be modeled in proportion to the intensity of the obtained X-ray diffraction beam.

For example, the wafer may be divided into a plurality of sections in the depth direction of the wafer depending on the degree of mechanical damage. And the thickness of each of the intervals can be set based on the intensity of the X-ray diffraction beam corresponding to each of the sampled strain values.

For example, the thickness of each section may be set proportional to the intensity of the X-ray diffraction beam corresponding to each of the sampled strain values. Since the intensity of the beam itself can vary depending on the measurement conditions, the approximate thickness of each section can be selected based on the intensity of the X-ray diffraction beam.

6 is a diagram for explaining modeling of degree of mechanical damage of the wafer shown in FIG.

Referring to FIG. 6, the degree of mechanical damage experienced by the wafer may be the most severe at the wafer surface, and the degree of mechanical damage may decrease with progression to the depth direction 603 of the wafer, .

Here, the surface 601 of the wafer may be the wafer surface on which the X-ray is incident, and the bulk 602 may be located inside the wafer. The depth direction 603 of the wafer may be the direction from the surface 601 of the wafer to the bulk 602.

The wafer may be divided into a plurality of sections (e.g., 612, 614, 616) in the depth direction 603 of the wafer depending on the degree of mechanical damage. It can be seen that the first section (e.g., 612) adjacent to the wafer surface 601 can have the largest strain value and the degree of mechanical damage is the greatest. It can also be seen that the third section (e. G., 616) adjacent to the bulk 602 may have the smallest strain value and the least degree of mechanical damage.

The thicknesses t1, t2, and t3 of each of the intervals (e.g., 612, 614, and 616) can be set based on the intensity of the X-ray diffraction beam corresponding to each of the sampled strain values S1, .

The thickness settings t1, t2, and t3 of the respective sections (e.g., 612, 614, and 616) may be as follows.

For example, assuming that the largest value of the calculated strains is 1000 ppm, intervals (e.g., 612, 614, 616) can be set while decreasing the strain value by 100 ppm.

The degree of damage decreases from the wafer surface toward the bulk direction. Therefore, even if the strain is divided at the same 100 ppm intervals, the smaller the strain value, the greater the thickness of the section.

As shown in FIG. 6, when the strain is divided into the sections S0, S1, S2 and S3, the thickness per strain can be increased (t0 <t1 <t2 <t3).

The strain values may be sampled and the intervals 610, 612, 614, and 616 corresponding to the sampled values S0, S1, S2, and S3 may be determined. At this time, the larger the value of the sampled skull, the lower the corresponding interval may be (e.g., S0-610).

The thicknesses t0, t1, t2 and t3 of the sections 610, 612, 614 and 616 can be set in proportion to the intensity of the diffracted beam corresponding to each of the sampled strain values S0, S1, S2 and S3.

5, the intensity of the X-ray diffraction beam increases sharply as the strain decreases, when the strain is divided by the isosceles at the strain value at the point where the intensity starts to be higher than the reference level 501 in the first swing curve shown in FIG. .

Next, a computer simulation is performed based on the modeling result of the degree of mechanical damage of the wafer, and a second shaking curve according to the simulation result is obtained (S140).

A computer simulation may be performed based on the modeling result and the measurement condition data in step S130, and a second shaking curve according to the simulation result may be obtained.

The result of modeling in step S130 may refer to strain (e.g., S0, S1, S2, S3) and thicknesses (t0, t1, t2, t3). The measurement conditions are the peak intensity of the first oscillation curve, the intensity of the reference level, the optical condition of the X-ray diffraction apparatus, the measurement interval of the X-axis, and the range of the set X-ray incidence angle of the first oscillation curve .

Figs. 7A to 7D show the process of matching the measured value of the first oscillation curve according to the embodiment, and the second oscillation curve according to the simulated result.

and f1 represents an actual value of the first oscillation curve obtained in step S220.

and f2 represents a second shaking curve according to the result of the computer simulation performed in step S140.

f3 denotes a second shaking curve according to the result of the computer simulation by the first matching, f4 denotes a second shaking curve according to the result of the computer simulation by the second matching, f5 denotes a computer simulation The result shows another second shaking curve.

The range of the X-ray incidence angle [theta] set at S320, the interplanar distance d calculated at S330, the sampled strain values extracted at S350, the angle modeled at S360 using the computer simulation program for calculating the X- It is possible to calculate a second shaking curve as shown in FIG. 7A by performing a computer simulation based on the thickness set for the section.

Next, the measured value of the first swing curve obtained in step S220 is matched with the second swing curve obtained in step S140 (step S150).

For example, by changing at least one of the positions of the peak intensities of the second oscillation curve, the range of the X-ray incidence angle?, The interplanar distance d, the sampled strain values, or the thicknesses of the respective sections, The second swinging curve can be made coincident with the actual value of the first swinging curve.

For example, by adjusting the sampled strain values or the thickness (e.g., t1, t2, t3) of each section (e.g., 612, 614, 616) in Fig. 6, the second shaking curve (e.g., f2 in Fig. (For example, f1 in Fig. 7). As shown in FIGS. 7B to 7D, this matching process may be repeated several times.

Next, the damage depth of the wafer is calculated based on the matched result (S160).

The simulation result of step S150 corresponds to the measured value of step S220, which means that the thickness set for each of the sampled strain values inputted in the simulation result coincides with the depth of damage actually possessed by the wafer.

Therefore, by summing all of the adjusted thicknesses for each of the sampled strain values inputted in the simulation result matched at step S150, it is possible to calculate the depth of damage of the wafer.

Embodiments can grasp the depth of mechanical damage of a wafer by a non-destructive method, and can easily grasp the depth of mechanical damage of a wafer which is difficult to be etched like a sapphire wafer.

Comparing the depth of damage measured by the method using etching and polishing for the same wafer and the depth of damage measured according to the example, it can be seen that the depth of damage measured according to the embodiment is deeper . This may mean that the embodiment can measure the depth of damage even for small-sized damage that is not identified by the method of using etching and polishing. That is, the embodiment can measure the mechanical damage depth more accurately than the method using etching and polishing.

8 is a graph showing the depth of damage measured according to the method G1 using etching and polishing and the method G2 according to the embodiment. Case 1 is the result of measuring the depth of damage of the sliced wafer, Case 2 is the result of measuring the depth of damage of the wafer after the lapping process, Case 3 is the depth of damage of the wafer before OISF heat treatment process after completion of the grinding process And Case 4 is a result of measuring the depth of damage of the wafer after completion of the grinding process and the OISF heat treatment process.

Referring to FIG. 8, it can be seen that the damage depth of G2 is observed to be 4 to 4.5 탆 deeper than the damage depth of G1. The difference is that in the case of G1, the etching is performed for 30 seconds for visualization, and then the microscope is observed. In the vicinity of the wafer surface where damage is great, damage layer can be observed through etching, This is because the damaged layer is not observed through etching in the bulk region of the wafer.

G1 cuts wafers, performs polishing and etching, and therefore takes a long time to measure the depth of damage and has a disadvantage of fracture analysis. In addition, since the depth of damage is not measured in Case 3 of G 1, it takes a long time to measure the depth of damage after OISF heat treatment.

On the other hand, the embodiment has the advantage of non-destruction. However, once a model of a prototype is established, it is necessary to use a model of each prototype as a model for each sample A slight deformation can lead to a damage depth assessment in a short time.

The features, structures, effects and the like described in the embodiments are included in at least one embodiment of the present invention and are not necessarily limited to one embodiment. Further, the features, structures, effects, and the like illustrated in the embodiments can be combined and modified by other persons having ordinary skill in the art to which the embodiments belong. Therefore, it should be understood that the present invention is not limited to these combinations and modifications.

601: Wafer surface 602: Bulk
612 to 616: a plurality of intervals.

Claims (13)

Obtaining a first oscillation curve for a wafer obtained using an X-ray diffraction apparatus;
The range of the X-ray incidence angle having the intensity higher than the reference level in the first swing curve is set, the inter-plane distance to the set X-ray incidence angle is calculated, and the strain value of the wafer is calculated using the calculated inter- Extracting sampled strain values based on the calculated strain values;
Modeling a thickness of the wafer based on the degree of damage of the wafer based on the intensity of the X-ray diffraction beam corresponding to the sampled strain values;
Obtaining a second oscillation curve based on the set X-ray incidence angle range, the calculated inter-surface distance, the sampled strain values, and the modeled thickness;
Matching the second oscillation curve with the first oscillation curve by varying at least one of the range of the X-ray incidence angle, the inter-surface distance, or the sampled strain values, or the modeled thickness; And
And calculating a damage depth of the wafer based on the matched result. &Lt; Desc / Clms Page number 19 &gt; 2. The method of claim 1, wherein obtaining the first swing curve comprises:
Setting points at which to evaluate crystallinity in the wafer;
Obtaining X-ray oscillation curves for the points of the set wafer; And
Comparing the half widths (Full Width at Half Maximum) of the X-ray oscillation curves of the set wafer points with each other, and obtaining the first oscillation curve according to the comparison result. How to measure damage depth. 3. The method of claim 2,
And selecting the first swing curve having the largest half-value width of the X-ray swing curve as the first swing curve. The method according to claim 1,
And setting the intensity of a diffracted beam in which the first oscillation curve is saturated to the reference level. The method according to claim 1,
Wherein the strain value of the wafer is a ratio of a distance between a subtracting surface and a reference plane, and the reference plane distance is an interplane distance corresponding to a value of the intensity of the diffracted beam having the largest intensity in the first swinging curve, And calculating a damage depth of the wafer, which is a difference between the reference plane distance and the reference plane distance. 2. The method of claim 1, wherein extracting the sampled strain values comprises:
And extracting the sampled strain values based on the highest of the calculated strain values. 2. The method of claim 1, wherein modeling the thickness of the wafer,
Obtaining an intensity of an X-ray diffraction beam corresponding to each of the sampled strain values; And
And modeling the thickness of the wafer in proportion to the degree of damage of the wafer in proportion to the intensity of the obtained X-ray diffraction beam. 2. The method of claim 1, wherein modeling the thickness of the wafer,
Dividing the wafer into a plurality of sections in a depth direction according to a degree of damage;
Obtaining an intensity of an X-ray diffraction beam corresponding to each of the sampled strain values; And
And setting a thickness of each of the plurality of sections in proportion to the intensity of the obtained X-ray diffraction beam. The method according to claim 1,
Wherein the wafer is a semiconductor wafer obtained by performing a slicing process on a monocrystalline ingot in the step of acquiring the first swing curve, or the lapping process, the grinding process, or the polishing process on the surface of the semiconductor wafer Wherein the wafer is a wafer that has undergone at least one of the at least two measurements. 9. The method of claim 8,
And the second shaking curve is matched with the first shaking curve by adjusting a thickness set for each of the plurality of sections. 11. The method of claim 10, wherein calculating the damage depth of the wafer comprises:
Summing the adjusted thicknesses of the plurality of sections and summing the result to a depth of damage of the wafer. 3. The method of claim 2,
Wherein the points to which the crystallinity is to be evaluated are at a midpoint of the wafer, an edge point, and a point that is one-half of the radius of the wafer. 3. The method of claim 2,
Wherein the points to be evaluated for crystallinity are spaced apart from each other in a radiation pattern.

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