JP2008222505A - Method for evaluating silicon single crystal wafer and method for producing silicon single crystal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for evaluating a silicon single crystal wafer which comprises judging an N(V) area and an N(I) area in an N region with ease and accuracy and without spending much time, and to provide a method for producing a silicon single crystal using the method. <P>SOLUTION: Provided is a method for evaluating the quality of a silicon single crystal wafer produced by using the CZ method which comprises heat-treating the silicon single crystal wafer in an oxidizing atmosphere, forming a shallow etch pit (shallow pit) by selective etching, and distinguishing the N(V) area and the N(I) area in a defect-free region on the basis of the above-formed etch pit. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for evaluating the quality of a silicon single crystal wafer by a CZ (Czochralski) method and a method for producing a silicon single crystal, and in particular, a method for evaluating a silicon single crystal wafer related to evaluation of a defect-free region and The present invention relates to a method for producing a silicon single crystal.

  Generally, when a silicon single crystal wafer is manufactured, first, the silicon single crystal is usually pulled up by the Czochralski method. In the pulling of this silicon single crystal, it is known that the type and concentration of point defects in the single crystal are determined by the ratio of the pulling speed V and the temperature gradient G in the vicinity of the solid-liquid interface, V / G.

  FIG. 3 shows an example of the relationship between the V / G value and the defect distribution. By changing the pulling rate V (mm / min) during single crystal growth, the ratio with the average value G (° C / mm) of the temperature gradient in the pulling axis in the temperature range from the silicon melting point to 1300 ° C. This is a case where a certain V / G is changed.

  First, as shown in the schematic diagram of the vertically divided sample in FIG. 3A, in a region where the pulling speed V is relatively high, voids that are vacancies that are point defects called vacancy (hereinafter also referred to as Va) are aggregated. COP (Crystal Originated Particle) and FPD (Flow Pattern Defect) vacancy-type Grown-in defects that exist in the entire crystal diameter are called V-Rich regions (V regions). .

When the pulling speed V becomes slightly slower than this, OSF is generated in a ring shape from the periphery of the crystal (OSF region), and as the pulling speed V decreases, the OSF shrinks toward the center, and finally at the center of the crystal. OSF disappears.
When the pulling speed V is further decreased, there is a neutral (hereinafter also referred to as “N”) region called Va or interstitial silicon (hereinafter also referred to as “I”) in which there is little excess or deficiency of interstitial point defects. Since this N region has a bias of Va and I but is below the saturation concentration, it does not exist as an agglomerated defect such as the COP or FPD, or the presence of a defect cannot be detected by the current defect detection method. It turns out.
This N region is divided into an N (V) region where Va is dominant and an N (I) region where I is dominant.

  When the pulling speed V is further decreased, I becomes supersaturated, and as a result, defects of L / D (Large Dislocation: abbreviations for interstitial dislocation loops, LSEPD, LEPD, etc.), which are considered to be dislocation loops in which I aggregates, occur at low density. This region is called an I-Rich region (I region).

  FIG. 3B shows the distribution of defect areas in the wafer surface cut out from each position of the vertically divided sample in FIG. Thus, it can be seen that the distribution of the defect region in the wafer surface changes depending on each cutting position.

Regarding the determination of the crystal defect region as described above, for example, the determination of the N region and the V region has been determined by using both the observation of the FPD density by an optical microscope after secco etching and the OSF density after the OSF heat treatment. .
In addition, the I region and the N region were distinguished from each other because dislocation clusters observed in the I region were observed as pits after seco etching.

  Incidentally, in recent years, the demand for the N region (COP and dislocation loop free region) crystal has increased, and at the same time, oxygen precipitation has become very important. The oxygen precipitation characteristics are greatly different between the N (V) region and the N (I) region. In the N (V) region, oxygen precipitates are easily formed, but in the N (I) region, oxygen precipitates are hardly formed.

Therefore, when manufacturing a wafer having a uniform in-plane oxygen precipitate density, it is necessary to manufacture the wafer limited to the N (V) region or the N (I) region. The determination of the manufacturing conditions of the single crystal that becomes such an N (V) region or N (I) region is carried out by conducting a gradual decrease test of the pulling rate in advance, producing vertically divided samples, performing oxygen precipitation heat treatment, and X-ray topography. In addition, the N (V) region and the N (I) region are discriminated based on the wafer lifetime and the defect distribution is confirmed.
For example, in the region where the OSF is formed, precipitation of interstitial oxygen does not occur, so the BMD density is low and the lifetime is high. In the N region having no growth defect, the N (V) region having a large amount of oxygen-precipitated BMD and the N (I) region having a small BMD are discriminated.

  However, in this method, sufficient oxygen precipitates cannot be formed in the N (V) region unless the oxygen concentration is 14 ppma (JEIDA) or more. ) It was not possible to contrast the boundaries of the areas, and these areas could not be distinguished. In addition, when this method is applied to mass-produced products for daily management, a long-time oxygen precipitation heat treatment (for example, 16 hours at 1000 ° C.) is required for a wafer cut from the manufactured single crystal. After that, it takes about 30 minutes for each sheet to measure and discriminate each defect area, which is not realistic.

  Patent Document 1 discloses a method for evaluating the quality of a silicon single crystal wafer, in which the surface of the silicon wafer is contaminated with Fe, and a defect-free region of the silicon single crystal is visually determined. This is simply a method for discriminating a defect-free region (N region), and is different from a method capable of discriminating an N (V) region and an N (I) region in the N region.

JP 2006-278892 A

  The present invention has been made in view of such problems, and at least the N (V) region and the N (I) region of the N region can be determined easily and accurately without taking time. An object of the present invention is to provide a method for evaluating a silicon single crystal wafer and a method for producing a silicon single crystal using the same. In particular, an object is to provide a method capable of determining even when the oxygen concentration is less than 14 ppma (JEIDA).

  In order to solve the above-mentioned problems, the present invention is a method for evaluating the quality of a silicon single crystal wafer produced by using the CZ method, wherein at least the silicon single crystal wafer is selected after heat treatment in an oxidizing atmosphere. A shallow etching pit (shallow pit) is formed by etching, and at least an N (V) region and an N (I) region of a defect-free region are discriminated from the formed etching pit. An evaluation method is provided (claim 1).

  In such an evaluation method of the present invention, after a silicon single crystal wafer is heat-treated in an oxidizing atmosphere, shallow pits are formed by selective etching, and at least an N (V) region, N (I) is formed from the shallow pits. Since the area can be identified, it is no longer necessary to distinguish between the N (V) and N (I) areas by X-ray topograph and wafer lifetime as in the conventional method, greatly increasing the amount of work and time required for these measurements. Can be reduced and shortened. Moreover, it does not require heat treatment as long as the oxygen precipitation heat treatment.

  Note that at least the N (V) region and the N (I) region of the defect-free region can be visually discriminated (Claim 2), and these regions can be distinguished very easily.

  At this time, as the heat treatment in the oxidizing atmosphere, heat treatment is performed in a dry oxygen atmosphere at 900 ° C. to 1100 ° C. for 1 hour to 5 hours, and then in a wet oxygen atmosphere at 1100 ° C. to 1200 ° C. It is preferable to perform a heat treatment for at least 3 hours and at most (Claim 3). In particular, at this time, the OSF region of the silicon single crystal wafer can also be determined.

  By performing heat treatment in such an oxidizing atmosphere, shallow pits can be reliably formed in the N (I) region, and OSF can be reliably generated in the OSF region. That is, the contrast of each defect area in the evaluation sample becomes clearer, and the distribution of the defect area can be determined very easily.

The silicon single crystal wafer to be evaluated can have an oxygen concentration of 10 ppma (JEIDA) or more and less than 14 ppma (JEIDA).
As described above, in the conventional method using the X-ray topograph or the wafer lifetime, when the oxygen concentration is less than 14 ppma (JEIDA), sufficient contrast can be provided between the N (V) region and the N (I) region. It was not possible to distinguish these areas. However, in the present invention, even if the oxygen concentration is less than 14 ppma (JEIDA), it can be determined with high accuracy. In this case, if the range is 10 ppma (JEIDA) or more, it is possible to easily distinguish these regions.

  Further, the present invention derives a production condition of a silicon single crystal in which the entire radial surface is an N (V) region or an N (I) region by the above-described silicon single crystal wafer evaluation method, and the derived production condition is A silicon single crystal manufacturing method is provided, wherein a silicon single crystal is manufactured based on the above.

  As described above, the silicon single crystal wafer evaluation method according to the present invention derives the production conditions for the silicon single crystal whose entire surface in the radial direction is the N (V) region or the N (I) region, and is based on this production condition. Thus, if a silicon single crystal is manufactured, it is possible to find a condition under which it is possible to easily and reliably manufacture a silicon single crystal whose entire surface in the radial direction is an N (V) region or an N (I) region. Therefore, if a silicon single crystal is manufactured based on this condition, a silicon single crystal in a COP-free region can be obtained, and a silicon single crystal in which oxygen precipitation, which has been emphasized in recent years, is uniform in the plane, is manufactured. can do.

With such a method for evaluating a silicon single crystal wafer of the present invention, it is not necessary to use an X-ray topograph or measure a wafer lifetime as in the conventional method. In addition, it is possible to easily determine each defective area by optical image processing using a CCD camera or the like, or by visual observation, so that the evaluation efficiency can be greatly improved.
And if it is the manufacturing method of the silicon single crystal using such an evaluation method of a silicon single crystal wafer, silicon where the whole surface of the radial direction becomes an N (V) region or an N (I) region very easily and surely A single crystal can be obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited thereto.
FIG. 1 shows an outline of an example of the procedure of the method for evaluating a silicon single crystal wafer of the present invention.
As shown in FIG. 1, first, a silicon single crystal wafer by CZ method is prepared (step 1). Next, the prepared silicon single crystal wafer is heat-treated in an oxidizing atmosphere (step 2), and selective etching is performed (step 3). As a result, a shallow pit is formed, and the distribution of various defect regions such as the N (V) region and the N (I) region is visually discriminated based on the shallow pit to evaluate the quality of the silicon single crystal wafer (process) 4).

(Step 1: Preparation of silicon single crystal wafer)
In step 1, a silicon single crystal wafer by the CZ method is prepared. For this, for example, a conventional silicon single crystal pulling apparatus may be used, and the silicon single crystal may be pulled by a method similar to the conventional method. The manufacturing conditions at this time can be appropriately determined according to the evaluation contents and the like. Then, the pulled silicon single crystal is sliced using a wire saw or the like to obtain a silicon single crystal wafer.

  Here, in the pulling of the silicon single crystal wafer, the pulling speed is intentionally slowed so that the distribution of the defect region as shown in FIG. 3A is obtained when the silicon single crystal is vertically divided. . In the following description, a case where a vertically divided sample as shown in FIG. 3A is used will be described. However, the present invention is naturally not limited to this, and it is possible to prepare a silicon single crystal wafer according to the content to be evaluated. it can.

After slicing, cleaning may be performed by pouring pure water over a silicon single crystal wafer, or mirror etching may be performed using a mixed acid (HF, HNO ₃ system). These treatments can be appropriately added so that the silicon single crystal wafer can be accurately evaluated by appropriately performing the oxidation step of step 2 and the selective etching step of step 3 performed after step 1.

(Process 2: Heat treatment in an oxidizing atmosphere)
Next, in step 2, the silicon single crystal wafer is subjected to heat treatment in an oxidizing atmosphere.
Here, the meaning of the heat treatment in the oxidizing atmosphere in step 2 will be described together with the characteristics of the evaluation method of the present invention.
When the evaluation sample is heat-treated in a heat treatment furnace, the surface of the evaluation sample is contaminated with a metal such as nickel from the heat treatment furnace.
At this time, for example, in the N (I) region having no gettering capability, this contaminated metal is not removed, and defects are deposited due to contamination by this metal such as nickel, and selective etching in the subsequent step 3 is performed. In addition, shallow pits are formed in the precipitation defects. Due to the formation of the shallow pits, the regions where the shallow pits are formed appear white turbid.
On the other hand, for example, in the N (V) region (and also the I region) having gettering capability, this contaminated metal is removed. There are only a few getter sites, and no white turbidity occurs when the selective etching in step 3 is performed.

  In the evaluation method of the present invention, such a phenomenon is used, and at least the adjacent N (V) region and N (I) region are visually observed in Step 4 depending on the presence or absence of white turbidity due to the formation of shallow pits. It can be easily identified. Furthermore, the OSF region and the like can be more reliably determined depending on the content of the oxidation heat treatment in step 2.

Specifically, for example, heat treatment is performed at 900 ° C. to 1100 ° C. for 1 hour to 5 hours in a dry oxygen atmosphere, and then, at 1100 ° C. to 1200 ° C. for 1 hour to 3 hours in a wet oxygen atmosphere. It is preferable to perform the heat treatment.
First, a metal such as nickel from the heat treatment furnace is diffused into the silicon single crystal wafer by the first heat treatment in a dry oxygen atmosphere, and defects are precipitated in the N (I) region due to the diffused metal. . Further, since the OSF is reliably formed by the subsequent heat treatment under the wet oxygen atmosphere (corresponding to the OSF treatment), the presence of the OSF and its region can be confirmed by observation under the condenser lamp.

  That is, by performing the heat treatment in an oxidizing atmosphere as described above in step 2, defects caused by the metal are not deposited in the V region, the N (V) region, and the I region. In the OSF region located between the N (V) region and the N (I) region located between the N (V) region and the I region, defects can be more reliably formed.

  The heat treatment conditions in this oxidizing atmosphere are not particularly limited, but at least the N (V) region and the N (I) region can be easily discriminated by the subsequent steps 3 and 4, such as nickel from the heat treatment. It is sufficient if the metal can be sufficiently diffused into the silicon single crystal wafer to form defects. It can be determined as appropriate according to the desired evaluation content (defect region to be evaluated) and the prepared silicon single crystal wafer.

(Process 3: Selective etching)
Next, selective etching is performed as step 3 on the silicon single crystal wafer subjected to the oxidation heat treatment in step 2.
Note that as the pretreatment, the oxide film formed on the surface of the silicon single crystal wafer in step 2 can be removed using, for example, hydrofluoric acid, and cleaning with pure water can be appropriately performed. . As described above, the silicon single crystal wafer can be pretreated so that the selective etching can be appropriately performed.

As a selective etching solution for revealing shallow pits, for example, Japanese Unexamined Patent Application Publication No. 2004-63721 discloses a mixed acid (HF, HNO ₃ system), a seco solution, and the like, but a mixed acid not containing chromium ( For example, it is preferable to use NIT solution. However, this selective etching solution is not particularly limited, and an appropriate one can be used each time.
The selective etching is performed by immersing the silicon single crystal wafer in such a selective etching solution.

By performing this selective etching, as described above, defects become apparent in the N (I) region where defects due to contaminating metals such as nickel exist, and also in the OSF region. That is, the N (I) region becomes white turbid due to the appearance of the shallow pit, and the OSF region can confirm the presence of the OSF and the region under the condenser lamp.
On the other hand, shallow pits are not formed and white turbidity is not formed in the N (V) region where defects due to the contaminated metal are not generated, and further in the V region and I region.

(Process 4: Visual quality evaluation)
In step 4, the quality of the silicon single crystal wafer after the selective etching in step 3 is evaluated. In the present invention, the distribution of the N (V) region, the N (I) region, and the like can be easily determined visually.
FIG. 2 shows a conventional evaluation method using an X-ray topograph (FIG. 2 (A)) and a case where the evaluation method of the present invention is used (FIG. 2 (B) for a vertically divided sample of silicon single crystal. )) Shows an example of an observation diagram of a silicon single crystal wafer.

Both are samples in which the V region, the OSF region, the N (V) region, the N (I) region, and the I region spread in order from the top of the figure. It can be seen that the defective area can be discriminated.
As can be seen from the case of the present invention in FIG. 2 (B), the white turbidity in the N (I) region is particularly remarkable, so that the contrast with the non-white turbid N (V) region is clear. It can be seen that the discrimination of the area is really easy.
In addition, the present invention does not require measurement work by an X-ray topograph or the like as in the conventional method, and since it is possible to discriminate each defective area visually under a condenser lamp, it is extremely simple and takes time. You do n’t have to. For this reason, it is possible to significantly improve the evaluation efficiency.

  In the example shown in FIG. 2, a sample having an oxygen concentration of 14 ppma (JEIDA) or more in the silicon single crystal wafer is used. In the conventional method, if the oxygen concentration is not 14 ppma (JEIDA) or more, sufficient oxygen precipitates cannot be formed in the N (V) region. Therefore, the boundary between the N (V) region and the N (I) region is set with contrast. It cannot be determined. That is, in the case of the conventional method, the boundary between the N (V) region and the N (I) region is blurred compared to FIG. 2A, and it becomes impossible to distinguish these regions.

  However, in the evaluation method of the present invention, even when the oxygen concentration is 10 ppma (JEIDA) or more and less than 14 ppma (JEIDA), the N (V) region and the N (I) region are discriminated with a clear contrast. Can be done.

  In FIG. 2, each sample is read by a commercially available scanner. However, in observation under condensing, the OSF region can be clearly confirmed and can be distinguished from other regions.

  In the method for producing a silicon single crystal according to the present invention, first, using the method for evaluating a silicon single crystal wafer according to the present invention, the entire surface in the radial direction is determined from the production conditions in Step 1 and the evaluation results in Step 4. Can derive optimum manufacturing conditions (particularly, control conditions for V / G) for pulling up the silicon single crystal in the N (V) region or N (I) region. V) crystals or N (I) crystals can be easily obtained. Since the N (V) region and the N (I) region can be confirmed in the N region, it is possible to accurately determine the adjustment of V / G, and no defective product is generated unnecessarily.

By such a manufacturing method, it is possible to easily and reliably produce a silicon single crystal having a free COP and a dislocation loop and uniform oxygen precipitation, and further cutting it out to produce a silicon single crystal wafer.
If the entire surface of the wafer can be made only in the N (V) region, the wafer is excellent in gettering ability. On the other hand, if an RTA heat treatment is performed on a wafer in the N (V) region, vacancies are injected by rapid cooling, and are very likely to precipitate, which deteriorates the oxide film breakdown voltage characteristics. It is possible to obtain an optimum wafer when performing the RTA heat treatment.

Naturally, silicon single crystal wafers such as a V region, an OSF region, and an I region can be obtained according to the purpose.
Depending on the purpose of use of the wafer, etc., desired production conditions can be appropriately determined from the evaluation method of the present invention, and a silicon single crystal wafer suitable for the purpose can be produced.

(Examples 1 and 2 and Comparative Example 1)
A vertically-divided sample was cut out from a silicon single crystal having a diameter of 200 mm and oxygen concentration increased to 5 levels and the pulling rate was gradually reduced, and the OSF region, N (V) region, N (I) It is evaluated whether the area and the I area can be discriminated. The oxygen concentration was 9.5 ppma, 10.0 ppma, 13.5 ppma, 14.0 ppma, 15.0 ppma (all are JEIDA).

After washing the sample cut out from the single crystal by pouring pure water for 2 minutes, mirror etching was performed. This mirror etching was performed by immersing in a mixed acid (HF 8%, HNO ₃ 48.3%, CH ₃ COOH 14.6%, H ₂ O 29.1%) for 10 minutes.
Thereafter, the sample was heat-treated in an oxidizing atmosphere using a diffusion furnace. That is, a heat treatment (first heat treatment) at 1000 ° C. for 180 minutes in a dry oxygen atmosphere, and then a heat treatment (second heat treatment) for 100 minutes at 1150 ° C. in a wet oxygen atmosphere. At this time, an oxide film was formed on the sample surface.

Next, the oxide film on the surface of the sample was removed by immersing in an HF solution (concentration 50%) for about 2 minutes, and then cleaning was performed by pouring pure water for 2 minutes.
Then, for selective etching, it is immersed in NIT solution (HF 3.7%, HNO ₃ 40%, CH ₃ COOH 10%, H ₂ O 46.3%) for 5 minutes, etched off by 7 μm, and using pure water. Washing was performed for 2 minutes.
The sample thus obtained was visually evaluated for defect distribution under a condenser lamp (Example 1).

Further, the evaluation method of the present invention was carried out in the same manner as in Example 1 except that the second heat treatment was a heat treatment at 1150 ° C. for 100 minutes in a dry oxygen atmosphere (Example 2).
Samples similar to those of Examples 1 and 2 were prepared, subjected to oxygen precipitation heat treatment (1000 ° C. for 16 hours), and evaluated by a conventional method using an X-ray topograph (Comparative Example 1).

The evaluation results of Examples 1 and 2 and Comparative Example 1 are shown in Table 1.
From Example 1, when the oxygen concentration is 10.0 ppma (JEIDA) or higher, that is, even if it is less than 14.0 ppma (JEIDA), the N (I) region becomes clouded, and it is clearly visually recognized as the N (V) region. I was able to distinguish. Further, since the OSF is also generated, the N (I) region and the OSF region can be distinguished from the V region, the N (V) region, and the I region. The boundaries of each defect area could be clearly identified.
In addition, when 9.5 ppma (JEIDA), OSF is not sufficiently formed, and the oxygen concentration is too low so that sufficient gettering effect of heavy metal is not exhibited even in the N (V) region and V region. It was slightly cloudy and the N (I) region was somewhat difficult to identify.

In Example 2, although the N (I) region became clouded and could be visually identified as the N (V) region, OSF did not occur, and the V region and the OSF region, the OSF region and the N (V) region, The distinction was difficult.
For this reason, it was found that the second heat treatment needs to be a wet atmosphere in order to deposit defects in the OSF region and form shallow pits by selective etching.

On the other hand, the results of Comparative Example 1 showed that when the oxygen concentration was 14.0 ppma (JEIDA) or higher, OSF was generated and the N (I) region became clouded, and each defect region could be discriminated. In the case of a low oxygen concentration of less than 0 ppma (JEIDA), although it became cloudy, the boundary between them was extremely blurred and OSF was not generated, and these defective areas could not be identified.
Further, in the conventional method of Comparative Example 1, unlike the present invention which can be immediately evaluated visually, the X-ray topograph requires about 30 minutes of time and work per sheet, so both time and labor are required. As a result, the evaluation efficiency and cost were poor compared to the present invention.

(Examples 3 to 6)
Evaluation was performed in the same manner as in Example 1 using a sample having an oxygen concentration of 14.0 ppma (JEIDA) (Example 3).
The sample was evaluated in the same manner as in Example 3 except that the heat treatment temperature of the second heat treatment was 1100 ° C. (Example 4), 1000 ° C. (Example 5), and 600 ° C. (Example 6). .

  The results of Examples 3 to 6 are shown in Table 2. In this way, the N (I) region became clouded in all cases, and was clearly distinguishable from the N (V) region. In the OSF region, it can be clearly confirmed under the condenser lamp, and it can be clearly distinguished from the V region and the N (V) region in Examples 3 and 4 where the heat treatment temperature of the second heat treatment is 1100 ° C. or higher. there were. From this, it can be seen that it is preferable to set the temperature to 1100 ° C. or higher in the second heat treatment in order to reliably generate OSF even in the OSF region and to be able to reliably discriminate these regions visually. A temperature of about 1200 ° C. is sufficient.

(Example 7)
From the evaluation results of Example 1, a production condition (V / G value) capable of pulling up the single crystal in the N (V) region was obtained, and the pulling up of the N (V) crystal was attempted based on this V / G value. It was.
When the silicon single crystal wafer was cut out from the pulled single crystal and the distribution of the defect region was investigated, it was N (V) crystal as desired.
Further, when the silicon single crystal was pulled up in the same procedure in the N (I) region and also in other defect regions, single crystals of the respective defect regions could be obtained.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  For example, the defect area is captured as an image with a CCD camera or the like under a condenser lamp, the image is digitized, and various image processes are performed to determine the defect area.

It is a flowchart which shows an example of the procedure of the evaluation method of the silicon single crystal wafer of this invention. It is an example of the observation figure of the silicon single crystal wafer when (A) the case of the conventional method using the X-ray topograph and (B) the evaluation method of the present invention are used for the vertically divided sample of the silicon single crystal. . It is explanatory drawing which shows an example of the relationship between V / G value and defect distribution. (A) It is an example of the defect distribution in a vertically divided sample. (B) It is an example of distribution of the defect area | region in the surface of the wafer cut out from each position of the vertically divided sample.

Claims (6)

  A method for evaluating the quality of a silicon single crystal wafer produced using the CZ method, wherein at least the silicon single crystal wafer is heat-treated in an oxidizing atmosphere and then shallow etch pits (shallow pits) are formed by selective etching. And at least an N (V) region and an N (I) region of a defect-free region are discriminated from the formed etch pits.   2. The method for evaluating a silicon single crystal wafer according to claim 1, wherein at least the N (V) region and the N (I) region of the defect-free region are discriminated visually.   As the heat treatment in the oxidizing atmosphere, heat treatment is performed in a dry oxygen atmosphere at 900 ° C. to 1100 ° C. for 1 hour to 5 hours, and then in a wet oxygen atmosphere at 1100 ° C. to 1200 ° C. for 1 hour to 3 The method for evaluating a silicon single crystal wafer according to claim 1 or 2, wherein a heat treatment is performed for a period of time or less.   4. The method for evaluating a silicon single crystal wafer according to claim 3, wherein an OSF region of the silicon single crystal wafer is also discriminated.   5. The silicon single crystal wafer according to claim 1, wherein the silicon single crystal wafer to be evaluated has an oxygen concentration of 10 ppma (JEIDA) or more and less than 14 ppma (JEIDA). Evaluation method.   The silicon single crystal wafer evaluation method according to any one of claims 1 to 5 is used to derive a silicon single crystal manufacturing condition in which the entire radial surface is an N (V) region or an N (I) region. A method for producing a silicon single crystal, comprising producing a silicon single crystal based on the derived production conditions.

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