KR20200051595A - Evaluation method of silicon wafer and manufacturing method of silicon wafer - Google Patents

Abstract

The present invention is a method for evaluating a silicon wafer, wherein the silicon wafer is subjected to an all-surface defect measurement process in which surface defects are measured in advance, an oxidation treatment of ozone water with respect to the silicon wafer, and formed on the surface of the silicon wafer. The cleaning process which alternately repeats the oxide film removal process by hydrofluoric acid in a condition that does not completely remove the oxide film and the surface defects are measured on the silicon wafer after the cleaning process, and the defects measured in the entire surface defect measurement process are It has an incremental defect measurement process for measuring an increased increase defect, and repeats the cleaning process and the increase defect measurement process several times alternately, and evaluates the silicon wafer based on the measurement result of the increase defect after each cleaning process. It is a method for evaluating a silicon wafer. Accordingly, there is provided a method of evaluating a silicon wafer capable of evaluating only defects of a processing factor such as polishing, excluding particles generated by washing or the like of crystal defects.

Description

Evaluation method of silicon wafer and manufacturing method of silicon wafer

The present invention relates to a method for evaluating a silicon wafer and a method for manufacturing a silicon wafer.

The quality of wafers after polishing is improving day by day, and in confirming the quality of wafers after polishing and cleaning, it is difficult to discriminate whether the identified abnormality is a polishing machine, a cleaning machine, or a crystal machine.

Currently, in order to evaluate the quality of the polishing state, there is no method other than following the trend of quality by polishing a large number of wafers, and it is difficult to evaluate because the quality difference varies according to various external factors. In addition, in the past, it has been very difficult to detect an abnormality in polishing quality even if the wafer after polishing is measured only once and an extraction test is performed as usual during the production of a large amount of wafers. In addition, in the stage where the outliers were clearly known, there were many cases where the time was already missed.

As a method for evaluating surface quality, there is a SC1-RT method, which is a method for evaluating defects of silicon crystallites and metal contamination, and a method for evaluating defects (machining defects) in processing machines such as polishing. No (Patent Document 1).

In addition, since the SC1-RT method uses an aqueous alkali solution, in principle, both Si and SiO ₂ are etched, so the deterioration of the wafer surface roughness is remarkable.

In addition, the conventional method for evaluating the quality of wafers by ozone water and HF treatment includes a process of removing (separating) all of the natural oxide film (Patent Document 2). Defects were present, and defects in processing such as polishing could not be evaluated.

Japanese Patent Publication No. 2002-353281 Japanese Patent Publication No. 2013-004760

The present invention has been made in view of the above problems, and an object of the present invention is to provide a method for evaluating a silicon wafer capable of evaluating only defects due to processing defects such as polishing, excluding particles generated due to defects or cleaning of crystal defects. .

In order to solve the above problems, the present invention is a method of evaluating a silicon wafer,

A surface defect measurement process for measuring surface defects in advance with respect to the silicon wafer;

A cleaning step of alternately repeating the silicon wafer with oxidation treatment with ozone water and the oxidation film removal treatment with hydrofluoric acid under conditions that do not completely remove the oxide film formed on the surface of the silicon wafer;

It has a surface defect measurement process for the silicon wafer after the cleaning process, and has an increase defect measurement process for measuring the increased increase defect for the defect measured in the surface defect measurement process,

Provided is a method for evaluating a silicon wafer, wherein the cleaning process and the increasing defect measurement process are alternately repeated a plurality of times, and the silicon wafer is evaluated based on the measurement result of the increasing defect after each cleaning process.

With this method of evaluating silicon wafers, it is possible to present only processing defects without presenting defects due to crystal defects in the cleaning process, and by looking at the tendency of increasing defects measured after each cleaning process, defects or cleaning of crystal defects Since it is possible to evaluate only the processing defects excluding particles generated by the back, etc., it is possible to evaluate the processing quality such as polishing.

In this case, it is preferable to perform the oxide film removal treatment by hydrofluoric acid in a condition where the oxide film is not completely removed, with a hydrofluoric acid concentration of 0.1 to 1.0% and a treatment time of 2 to 20 seconds.

When the oxide film removal treatment using hydrofluoric acid is used, the thickness of the native oxide film can be controlled, so that the oxide film can be removed without completely removing the oxide film.

Further, in this case, it is preferable that the washing step is alternately (alternately) repeated five or more times by the oxidation treatment with ozone water and the oxidation film removal treatment with hydrofluoric acid.

Thus, by repeating the oxidation treatment with ozone water and the oxidation film removal treatment with hydrofluoric acid five or more times, it is possible to reliably correct the processing defect, so that the processing quality can be more accurately evaluated.

Moreover, in this case, it is preferable to use the thing after mirror polishing as said silicon wafer.

In the method of evaluating the silicon wafer of the present invention, the polishing quality can be evaluated by using the silicon wafer after mirror polishing.

In addition, in the method for evaluating a silicon wafer of the present invention, it is possible to evaluate a defect of the processing cause of the silicon wafer based on the measurement result of the increase defect after each cleaning step.

In the method of evaluating the silicon wafer of the present invention, only processing defects such as polishing can be present in the cleaning process, and by looking at the increasing tendency of increasing defects measured after each cleaning process, only defects of the processing machine can be evaluated, and thus processing is performed. It is possible to evaluate quality.

In addition, the present invention is a method of manufacturing a silicon wafer to be a product by performing mirror polishing on a silicon wafer before mirror polishing,

The process of preparing the experimental silicon wafer before mirror polishing,

A step of performing mirror polishing on the experimental silicon wafer before the mirror polishing under predetermined mirror polishing conditions;

For the above-described silicon wafer for testing, a surface defect measurement process for measuring surface defects in advance,

A cleaning process alternately repeating the oxidation treatment with ozone water and the removal of the oxide film with hydrofluoric acid under conditions that do not completely remove the oxide film formed on the surface of the experimental silicon wafer, for the experimental silicon wafer;

After the cleaning process, a surface defect measurement is performed on the silicon wafer for testing, and an increase defect measurement process is performed to measure increased defects in the defects measured in the entire surface defect measurement process.

The cleaning process and the increase defect measurement process are alternately repeated multiple times, and the experimental silicon wafer is evaluated based on the measurement result of the increase defect after each cleaning process.

Based on the evaluation of the experimental silicon wafer, the mirror polishing conditions in the mirror polishing are specified so that the polishing quality after mirror polishing of the silicon wafer before the mirror polishing is a desired polishing quality,

Provided is a method for manufacturing a silicon wafer, wherein the silicon wafer serving as the product is manufactured by performing mirror polishing on the silicon wafer before the mirror polishing under the specific mirror polishing conditions.

With this method of manufacturing a silicon wafer, it is possible to present only the processing defects without presenting defects of crystallites in the cleaning process for the experimental silicon wafers, and by looking at the increasing tendency of the increase in defects measured after each cleaning process, It becomes possible to evaluate only the processing defects, excluding particles generated by defects or cleaning. By this experiment, it is possible to specify whether the desired polishing quality is obtained by performing mirror polishing on a silicon wafer before mirror polishing under certain mirror polishing conditions. By manufacturing the silicon wafer under such specific mirror polishing conditions, it is possible to manufacture a mirror polished silicon wafer having a desired polishing quality.

In the method of evaluating the silicon wafer of the present invention, it is possible to present only the processing defects without presenting defects of crystallites in the cleaning process, and also by looking at the tendency of increasing defects measured after each cleaning process, It is possible to evaluate only processing defects due to polishing or the like, excluding particles generated by defects or cleaning. Further, in the present invention, cleaning can be performed without deteriorating the surface roughness of the wafer, and measurement at a small particle size becomes possible. In addition, in the method for manufacturing a silicon wafer of the present invention, it is possible to manufacture a mirror polished silicon wafer having a desired polishing quality by specifying mirror polishing conditions based on evaluation of an experimental silicon wafer for evaluating only processing defects.

1 is a process flow chart showing an embodiment of a method for evaluating a silicon wafer of the present invention.
Fig. 2 is a graph showing the relationship between the total number of iterations of the treatment with ozone water and the treatment with hydrofluoric acid in the Examples and the increase defect function.
Fig. 3 is an SEM image of the wafer surface after cleaning in Example (A), and an SEM image of defects detected in Comparative Example (B).

As described above, in the conventional method for evaluating silicon wafers, there is a problem in that defects in crystal defects are present, and processing defects such as polishing cannot be evaluated.

In addition, the present inventors have repeatedly studied in order to solve the above problems, and as a result, alternately the oxidation treatment with ozone water and the oxidation treatment with hydrofluoric acid under conditions that do not completely remove the oxide film formed on the surface of the silicon wafer. The repeated cleaning process and the surface defect measurement of the silicon wafer after the cleaning process are repeated, and the incremental defect measurement process of measuring the increased increase defects for the defects measured in the entire surface defect measurement process is alternately repeated multiple times. When the silicon wafer is evaluated based on the measurement result of the increase defect after the cleaning process, only the defect of the process defect can be present without presenting the defect of the crystal defect in the cleaning process, and only the defect of the process defect such as polishing can be evaluated. It was discovered that the present invention was reached.

That is, the present invention is a method for evaluating a silicon wafer,

For the silicon wafer, the entire surface defect measurement process for measuring surface defects in advance,

A cleaning step of alternately repeating the silicon wafer with oxidation treatment with ozone water and the oxidation film removal treatment with hydrofluoric acid under conditions that do not completely remove the oxide film formed on the surface of the silicon wafer;

It has a surface defect measurement process for the silicon wafer after the cleaning process, and has an increase defect measurement process for measuring the increased increase defects for the defects measured in the all surface defect measurement process,

Provided is a method for evaluating a silicon wafer, wherein the cleaning process and the increasing defect measurement process are alternately repeated a plurality of times, and the silicon wafer is evaluated based on the measurement result of the increasing defect after each cleaning process.

Hereinafter, the evaluation method of the silicon wafer of the present invention will be described. 1 is a process flow diagram showing an embodiment of a method for evaluating a silicon wafer of the present invention.

The silicon wafer to be evaluated is not particularly limited, but a silicon wafer after mirror polishing is preferable. When a silicon wafer after mirror polishing is used, defects of a polishing machine such as PID (Polishing Induced Defect) can be evaluated, and polishing quality can be evaluated.

First, an all-surface defect measurement process in which surface defects are measured in advance is performed on the silicon wafer to be evaluated (Fig. 1 (a)). For example, it can be carried out using Surfscan SP5 manufactured by KLA-Tencor. Since there are few particle sizes larger than 40 nm in processing defects, the measurement particle size is sufficient to be 40 nm or less.

Subsequently, a cleaning process is performed in which the oxidation treatment with ozone water and the oxidation film removal treatment with hydrofluoric acid are alternately repeated under conditions that do not completely remove the oxide film formed on the surface of the silicon wafer (Fig. 1 (b)). It is preferable to perform this washing process with a single sheet washing apparatus.

The washing step (b) is a step of presenting processing defects such as polishing. By removing the oxide film by hydrofluoric acid and reoxidizing the surface of the wafer with ozone water without completely removing the oxide film, defects of crystallites are not present, but only processing defects such as polishing can be present.

In the conventional SC1-RT method (for example, Japanese Patent Laid-Open No. 2000-208578) or the conventional method for evaluating the quality of wafers by ozone water and HF treatment, processing defects such as polishing cannot be evaluated. By repeatedly washing with ozone water and hydrofluoric acid without completely removing the oxide film, it is possible to evaluate the defects of the crystallization defects by presenting the defects instead of the crystallization defects. In addition, cleaning can be performed without deteriorating the surface roughness of the wafer, and measurement at a small particle size becomes possible.

In this way, it is possible to evaluate only processing defects by presenting only processing defects such as polishing.

On the other hand, the reason why it is possible to present only the processing defects such as polishing without presenting defects of crystallites in the cleaning step (b) in the present invention is as follows. The processing defect is a deterioration layer due to deformation of the wafer during processing such as polishing. Although the oxide film of the wafer is removed by hydrofluoric acid, the oxide film of the portion of the processed deterioration layer becomes an etching rate different from that of the surrounding oxide film, and it becomes current by alternately repeating treatment with ozone water and treatment with hydrofluoric acid. This causes an etch process that leaves an oxide film by hydrofluoric acid, resulting in a difference in the thickness of the oxide layer between the processed deterioration layer and the surrounding location (the oxide film in the portion of the process deterioration layer is thick), and re-forming the oxide film with ozone water (the oxide film thickness is This is because the difference becomes more remarkable by repeatedly performing the treatment (returning uniformly). When the oxide film is completely removed, the oxide layer portion of the processed deterioration layer is also removed, so even if repeated ozone water treatment and hydrofluoric acid treatment are performed, there is no difference in the oxide film thickness and no current occurs, and it is impossible to evaluate defects due to processing defects.

In addition, by repeating ozone water and hydrofluoric acid treatment without completely removing the oxide film as in the present invention, the amount of etching is reduced to leave the oxide film at all times, thereby presenting defects such as crystal defects such as oxygen precipitates and pits due to metal contamination. There is nothing.

On the other hand, in the conventional SC1-RT method, not only processing defects, but also crystal defects such as oxygen precipitates are present by currentization by performing a large amount of etching.

In addition, the conventional method for evaluating wafer quality by ozone water and HF treatment includes a process of removing (separating) all of the natural oxide film, and evaluating without deteriorating surface roughness by completely removing the oxide film using ozone water and hydrofluoric acid. It is possible to do this, but in this method, crystal defects are also present when removing the natural oxide film by HF.

The ozone concentration of the ozone water in the present invention is not particularly limited, but is preferably 5 ppm to 30 ppm. In order to produce a natural oxide film, it is preferable to be 5 ppm or more, and from the viewpoint of a practical execution concentration, it is preferable to be 30 ppm or less. In addition, the treatment time with ozone water per time is preferably 10 seconds or more in order to produce a natural oxide film.

The hydrofluoric acid concentration is not particularly limited, but is preferably 0.1 to 1.0%. If it is 0.1% or more, it is preferable because concentration control can be accurately performed. Moreover, in order to control the film thickness of a natural oxide film, it is preferable to set it as 1.0% or less. In addition, the hydrofluoric acid treatment time per time is preferably about 2 to 20 seconds. If it is 2 seconds or more, the hydrofluoric acid supplied to the wafer spreads evenly, and if it is 20 seconds or less, it is preferable because the oxide film can be removed and the oxide film removal treatment can be performed.

The number of repetitions of the oxidation treatment with ozone water and the removal of the oxide film with hydrofluoric acid is preferably about 5 to 50 times. If the number of repetitions is 5 or more, it is possible to make the machining defect presently. Moreover, since it is 50 times or less, the cleaning process time can be suppressed, and since throughput increases, it is preferable. Furthermore, if it is 50 times or less, it is preferable because it can be evaluated without deteriorating the surface roughness of the silicon wafer. In addition, it is sufficient since it is possible to grasp the tendency of the processing quality of the wafer without repeating more than 50 times.

Subsequently, surface defect measurement is performed on the silicon wafer after the cleaning step (b), and an incremental defect measurement step (c) is performed to measure the increased incremental defect with respect to the defects measured in the entire surface defect measurement step (a).

In this incremental defect measurement step (c), only the number of defects increased with respect to the defects measured in the entire surface defect measurement step (a) is measured. The measurement is, for example, by using the KLA-Tencor Surfsurf SP5 manufactured by KLA-Tencor, as in the entire surface defect measurement process, by measuring the kinematic coordinates, it is possible to measure the increase in the number of increased defects only.

Thereafter, the washing step (b) and the increase defect measurement step (c) are performed again. This is performed a plurality of times, and the silicon wafer is evaluated based on the measurement result of the increase defect after each cleaning step, for example, the increase tendency (slope) of the increase defect or the increase amount of the increase defect.

As described above, by performing a plurality of alternating cleaning process (b) and increasing defect measurement process (c) multiple times, and evaluating the silicon wafer based on the measurement result of the increasing defect (the slope of the increasing defect or the increasing defect number), defects of crystal defects Except for particles generated by cleaning or cleaning, only processing defects such as polishing can be evaluated.

If the processing conditions, such as polishing, are good, defects of the machine cause do not occur (because there is little), so even if the cleaning process (b) and the increase defect measurement process (c) are repeated, the slope of the increase in the increase defect is small, and the increase defect The number is small. On the other hand, if the quality of the polishing process is poor, defects in the machine cause, so repeating cleaning and measuring surface defects increases the slope of the increase in the increase in defects and increases the number of defects. By evaluating the quality of abrasive processing based on this slope or increasing defect function, it is possible to confirm the machining state at that time.

That is, when the linear approximation of the increase defect is taken, the larger the slope or the larger the increase defect, the more the potential machining defects are included, and the processing quality deteriorates.

As described above, in the present invention, by repeatedly washing without completely removing the oxide film using ozone water and hydrofluoric acid, not only deterioration of the surface roughness of the wafer or adhesion of particles, etc., but also defects of crystallinity are present. It is possible to present only processing defects, such as polishing, without making it chemical. In addition, by looking at the increasing tendency of the increase defects measured after each cleaning step, only defects of the process defects such as polishing can be evaluated, excluding defects of crystal defects and particles generated by cleaning and the like. In addition, it is possible to evaluate defects in micro domains that have never been available before.

In addition, the method for evaluating the silicon wafer can be applied to a method of manufacturing a silicon wafer to be a product by performing mirror polishing on a silicon wafer before mirror polishing. In this method of manufacturing a silicon wafer, before manufacturing a silicon wafer to be a product, an experiment according to the evaluation method of the silicon wafer is performed on the experimental silicon wafer, and mirror polishing conditions in mirror polishing are specified in advance, and a specific mirror surface Surface polishing is performed under polishing conditions to manufacture a silicon wafer to be a product. Specifically, a silicon wafer is manufactured as follows.

First, an experimental silicon wafer before mirror polishing is prepared. Next, the silicon wafer for an experiment before this mirror polishing is subjected to mirror polishing under predetermined mirror polishing conditions. In this way, for the experimental silicon wafer subjected to mirror polishing, the entire surface defect measurement process, the cleaning process, and the increase defect measurement process are performed in the same manner as in the evaluation method of the silicon wafer described above (see Figs. 1 (a) to (c)). . Specifically, each step is performed as follows. First, an all-surface defect measurement process in which surface defects are measured in advance is performed on an experimental silicon wafer subjected to mirror polishing. Next, the cleaning process is repeated for the experimental silicon wafer by alternately repeating the oxidation process with ozone water and the oxidation film removal process with hydrofluoric acid under conditions that do not completely remove the oxide film formed on the surface of the experimental silicon wafer. Next, surface defect measurement is performed on the experimental silicon wafer after the cleaning process, and an incremental defect measurement process is performed to measure increased incremental defects with respect to the defects measured in the entire surface defect measurement process.

The cleaning process and the increase defect measurement process are alternately repeated multiple times, and an experimental silicon wafer is evaluated based on the measurement result of the increase defect after each cleaning process. Further, based on the evaluation of the silicon wafer for experiment, specular polishing conditions in mirror polishing are specified so that the polishing quality after mirror polishing of the silicon wafer before mirror polishing is a desired polishing quality. Here, under specific mirror polishing conditions, a silicon wafer that is a product is manufactured by performing mirror polishing on a silicon wafer before mirror polishing.

The mirror polished silicon wafer polished under polishing conditions in which processing defects after mirror polishing do not occur (less) are repeated even after the cleaning process (b) and the increase defect measurement process (c), the slope of the increase of the increase defect is small and increases. The number of defects is small. On the other hand, if the quality of the polishing process is poor, defects in the machine cause, so repeating cleaning and measuring surface defects increases the slope of the increase in the increase in defects and increases the number of defects. By evaluating the polishing quality of the experimental silicon wafer on the basis of this slope or increasing defect function, it is possible to specify which polishing quality is desired if mirror polishing is performed on the silicon wafer before the mirror polishing under certain polishing conditions. .

More specifically, when a linear approximation of an increase defect is taken, it is possible to select a mirror polishing condition in which there is no or less slope. For example, in the flow shown in FIG. 1, the mirror polishing conditions can be set by setting the increase defects per 10 repetitions of hydrofluoric acid → ozone water to be 10 or less, 5 or less, or 1 or less on average.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

(Example)

All surface defects were measured using silicon wafers finally polished under different polishing conditions (polishing conditions 1 to 4) and cleaning was completed (Fig. 1 (a)). The wafer on which the entire surface defect was measured was washed by alternately repeating the oxidation treatment with ozone water and the oxidation film removal treatment with hydrofluoric acid (Fig. 1 (b)).

The washing conditions were 10 ppm of ozone water, 20 seconds of ozone water treatment time, 0.3% of hydrofluoric acid concentration, 5 seconds of hydrofluoric acid treatment time, and the flow shown in FIG. 1 was repeated with 5 times of hydrofluoric acid → ozone water washing. And then dried. On the other hand, in all the hydrofluoric acid treatments, oxide films were removed while leaving a thickness on the wafer surface.

Subsequently, surface defects were measured on the silicon wafer after the cleaning step, and increased incremental defects were measured for the defects measured in the entire surface defect measurement step (a) (Fig. 1 (c)). On the other hand, for the measurement of the total surface defect and the measurement of the increase defect, only the increased increase defect was measured by measuring with a particle diameter of 19 nm or more using Surfscan SP5 manufactured by KLA-Tencor, and by measuring the coordinate coordinates.

Washing process and increasing defect measurement process, until the total number of repetitions of treatment with ozone water → treatment with hydrofluoric acid is 50 times (ie, until the repetition number of cleaning process and increasing defect measurement process is 10 times). , Repeatedly.

Table 1 summarizes the total number of repetitions of the treatment with ozone water and the treatment with hydrofluoric acid and the increase in the number of defects, with only the increased number of defects as the incremental defect for the results of the total surface defect measurement after each cleaning step. Fig. 2 shows a graph plotting the relationship between the total number of iterations of the treatment with ozone water and the treatment with hydrofluoric acid and the increase defect function. Based on Table 1 and FIG. 2, the slope of the increase of the increase defects or the increase amount of the defects was evaluated.

In addition, as a result of observing the wafer surface after cleaning by SEM, it can be seen that crystal defects are not present on the wafer surface, and only processing defects as shown in FIG. 3 (A) are present. It was found that evaluation is possible.

As shown in Fig. 2, in the polishing conditions 1 to 4, the slope of the increase in the increase defect is different for each polishing condition, and the polishing condition 1 has little inclination of the increase, so that there is no defect of the machine cause, that is, the polishing quality. I knew it was good. In addition, it was found that in the polishing conditions 2 to 4, the higher the slope of the increase, that is, in the order of the polishing conditions 4, polishing conditions 3, and polishing conditions 2, the polishing quality was poor.

[Table 1]

(Comparative example)

The silicon wafer was evaluated by the evaluation method by the SC1-RT method described in Japanese Patent Laid-Open No. 2000-208578. Specifically, a defect was detected by using a treatment solution consisting of ammonia, hydrogen peroxide and water, and etching the surface of the silicon wafer. However, what was detected in the process was mainly particles and crystal defects as shown in Fig. 3B. Moreover, even when Surfscan SP5 manufactured by KLA-Tencor was used, the surface roughness was deteriorated at a particle size of 19 nm or more, and thus measurement was impossible.

In addition, this invention is not limited to the said embodiment. The above-mentioned embodiment is an example, and it has substantially the same structure as the technical idea described in the claims of the present invention, and any thing that exhibits the same working effect is included in the technical scope of the present invention.

Claims (6)

As a method of evaluating a silicon wafer,
For the silicon wafer, the entire surface defect measurement process for measuring surface defects in advance,
A cleaning step of alternately repeating the silicon wafer with oxidation treatment with ozone water and the oxidation film removal treatment with hydrofluoric acid under conditions that do not completely remove the oxide film formed on the surface of the silicon wafer;
It has a surface defect measurement process for the silicon wafer after the cleaning process, and has an increase defect measurement process for measuring the increased increase defects for the defects measured in the all surface defect measurement process,
A method of evaluating a silicon wafer, characterized in that the cleaning process and the increasing defect measurement process are alternately repeated a plurality of times, and the silicon wafer is evaluated based on the measurement result of the increasing defect after each cleaning process. According to claim 1,
A method for evaluating a silicon wafer, wherein the oxide film removal treatment by hydrofluoric acid is performed with a hydrofluoric acid concentration of 0.1 to 1.0% and a processing time of 2 to 20 seconds under the condition that the oxide film is not completely removed. The method according to claim 1 or 2,
A method of evaluating a silicon wafer, characterized in that the washing step is repeated five or more times alternately with the oxidation treatment with ozone water and the oxidation film removal treatment with hydrofluoric acid. The method according to any one of claims 1 to 3,
As the silicon wafer, a method of evaluating a silicon wafer, characterized in that one after mirror polishing is used. The method according to any one of claims 1 to 4,
A method of evaluating a silicon wafer, characterized in that a defect of the processing wafer of the silicon wafer is evaluated based on the measurement result of the increasing defect after each cleaning step. As a method of manufacturing a silicon wafer to be a product by performing a mirror-polishing of the silicon wafer before the mirror polishing,
The process of preparing an experimental silicon wafer before mirror polishing,
A step of performing mirror polishing on the experimental silicon wafer before the mirror polishing under predetermined mirror polishing conditions;
For the silicon wafer for the experiment, a surface defect measurement process for measuring surface defects in advance,
A cleaning process alternately repeating the oxidation treatment with ozone water and the removal of the oxide film with hydrofluoric acid under conditions that do not completely remove the oxide film formed on the surface of the experimental silicon wafer, for the experimental silicon wafer;
It has a surface defect measurement process for the experimental silicon wafer after the cleaning process, and has an increase defect measurement process for measuring the increased increase defects for the defects measured in the all surface defect measurement process,
The cleaning process and the increase defect measurement process are alternately repeated multiple times, and the experimental silicon wafer is evaluated based on the measurement result of the increase defect after each cleaning process.
Based on the evaluation of the experimental silicon wafer, specular polishing conditions in the mirror polishing are specified so that the polishing quality after mirror polishing of the silicon wafer before the mirror polishing is a desired polishing quality,
A method of manufacturing a silicon wafer, wherein the silicon wafer serving as the product is manufactured by performing mirror polishing on the silicon wafer before the mirror polishing under the specific mirror polishing conditions.

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