JP2019047108A - Method for evaluating silicon wafer and method for manufacturing silicon wafer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a silicon wafer evaluation method capable of evaluating only defects caused by processing such as polishing, excluding defects caused by crystals and particles generated by cleaning and the like. A method of evaluating a silicon wafer, comprising: a front surface defect measuring step of measuring a surface defect in advance on the silicon wafer; an oxidation treatment of the silicon wafer with ozone water; A cleaning step of alternately repeating the oxide film removal treatment with hydrofluoric acid under the condition that the oxide film formed on the surface is not completely removed, and performing surface defect measurement on the silicon wafer after the cleaning step, It has an increased defect measurement step of measuring increased defects increased with respect to the defects measured in the front surface defect measurement step, and the cleaning step and the increased defect measurement step are alternately repeated a plurality of times, after each cleaning step. 2. A method of evaluating a silicon wafer, comprising: evaluating the silicon wafer based on the measurement result of the increased defect. [Selection diagram] Figure 1

Description

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

  The quality of wafers after polishing is improving day by day, and when checking the quality of wafers after polishing and cleaning, it has become difficult to distinguish whether the identified abnormality is due to polishing, cleaning or crystals. There is.

  At present, in order to evaluate the quality of the polished state, it is only possible to polish a large number of wafers and follow the trend of the quality, and the evaluation is difficult because the difference in the quality changes due to various external factors. Also, conventionally, it is only necessary to measure the wafer after polishing once, and it is very difficult to detect an abnormality in the polishing quality even if a sampling inspection is conventionally performed while manufacturing a huge amount of wafers. was difficult. Moreover, it was often too late when the outliers were clearly understood.

  Although there is SC1-RT method as a conventional evaluation method of surface quality, this is a method for evaluating defects caused by silicon crystals and metal contamination, and defects (processing defects) caused by processing such as polishing are evaluated. It is not a method to do it (patent document 1).

In addition, since the SC1-RT method uses an alkaline aqueous solution, both Si and SiO ₂ are etched in principle, so that the wafer surface roughness is significantly deteriorated.

  In addition, the conventional method for evaluating the quality of a wafer by ozone water and HF treatment includes a step of removing (stripping) all natural oxide films (Patent Document 2), and thus completely removing the oxide film Then, crystal-induced defects would occur, and processing defects such as polishing could not be evaluated.

JP 2002-353281 A JP, 2013-004760, A

  The present invention has been made in view of the above problems, and it is a silicon wafer that can evaluate only defects caused by processing such as polishing excluding defects caused by crystal and particles generated by cleaning and the like. The purpose is to provide an evaluation method.

In order to solve the above problems, the present invention is a method for evaluating a silicon wafer,
A front surface defect measurement step of performing surface defect measurement in advance on the silicon wafer;
A cleaning step of alternately repeating the oxidation treatment with ozone water and the oxide film removal treatment with hydrofluoric acid under the condition that the oxide film formed on the surface of the silicon wafer is not completely removed from the silicon wafer;
The surface defect measurement is performed on the silicon wafer after the cleaning step, and the increase defect measurement step of measuring an increase defect increased with respect to the defect measured in the front surface defect measurement step,
A method of evaluating a silicon wafer is provided, wherein the cleaning step and the increase defect measuring step are alternately repeated plural times, and the silicon wafer is evaluated based on the measurement result of the increase defect after each cleaning step. .

  With such a silicon wafer evaluation method, it is possible to reveal only processing defects without revealing crystal-induced defects in the cleaning step, and see an increasing tendency of increased defects measured after each cleaning step. As a result, it becomes possible to evaluate only processing defects excluding defects caused by crystals and particles generated in cleaning and the like, and processing quality such as polishing can be evaluated.

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

  With such an oxide film removing process using hydrofluoric acid, the natural oxide film thickness can be controlled, so that the oxide film can be removed more reliably without completely removing the oxide film.

  In this case, it is preferable that the cleaning process is alternately repeated five times or more by the oxidation treatment with ozone water and the oxide film removal treatment with hydrofluoric acid.

  As described above, by repeating the oxidation treatment with ozone water and the oxide film removal treatment with hydrofluoric acid five times or more, since processing defects can be surely made to appear, the processing quality can be evaluated more accurately. .

  Further, in this case, it is preferable to use a mirror-polished wafer as the silicon wafer.

  In the evaluation method of a silicon wafer according to the present invention, the quality of polishing can be evaluated by using the silicon wafer after mirror polishing.

  Further, in the silicon wafer evaluation method of the present invention, it is possible to evaluate defects caused by processing of the silicon wafer based on the measurement results of the increased defects after the cleaning steps.

  In the method for evaluating a silicon wafer according to the present invention, only processing defects such as polishing can be made apparent in the cleaning step, and only defects due to processing can be observed by observing the increasing tendency of increased defects measured after each cleaning step. It is possible to evaluate the processing quality because it can be evaluated.

Further, the present invention is a method of manufacturing a silicon wafer to be a product by mirror-polishing a silicon wafer before mirror-polishing,
Preparing an experimental silicon wafer before mirror polishing;
Mirror-polishing the experimental silicon wafer before mirror-polishing under predetermined mirror-polishing conditions;
A front surface defect measurement step of performing surface defect measurement in advance on the experimental silicon wafer;
Cleaning the silicon wafer for the experiment alternately by the oxidation treatment with ozone water and the oxide film removal treatment with hydrofluoric acid under the condition that the oxide film formed on the surface of the silicon wafer for experiment is not completely removed Process,
Carrying out surface defect measurement on the experimental silicon wafer after the cleaning step and measuring an increase defect for the defects measured in the front surface defect measurement step;
The cleaning step and the increase defect measuring step are alternately repeated plural times, and the experimental silicon wafer is evaluated based on the measurement result of the increase defect after each cleaning step,
Based on the evaluation of the experimental silicon wafer, the mirror polishing condition in the mirror polishing is specified such that the polishing quality after the mirror polishing is performed on the silicon wafer before the mirror polishing becomes a desired polishing quality,
According to the present invention, there is provided a method of manufacturing a silicon wafer, wherein the silicon wafer before mirror polishing is mirror-polished under the mirror polishing conditions specified above to produce a silicon wafer as the product.

  With such a method for manufacturing a silicon wafer, only processing defects can be made apparent in the experimental silicon wafer without causing crystal-induced defects in the cleaning step, and increased defects measured after each cleaning step It becomes possible to evaluate only the processing defects excluding the defects caused by the crystal, the particles generated in the cleaning, and the like by observing the increasing tendency of. By this experiment, it is possible to specify under what mirror polishing conditions the mirror polishing is performed on a silicon wafer before mirror polishing to obtain desired polishing quality. By producing a silicon wafer under the mirror polishing conditions thus specified, it is possible to produce a mirror-polished silicon wafer having a desired polishing quality.

  According to the evaluation method of a silicon wafer of the present invention, only processing defects can be revealed in the cleaning step without revealing crystal-induced defects, and the increasing tendency of increase defects measured after each cleaning step is observed. Thus, it is possible to evaluate only processing defects due to polishing or the like excluding crystal-induced defects and particles and the like generated in cleaning and the like. Further, in the present invention, cleaning can be performed without deteriorating the surface roughness of the wafer, and measurement with a small particle diameter can be performed. Further, in the method for producing a silicon wafer according to the present invention, a mirror-polished silicon wafer having desired polishing quality is manufactured by specifying mirror-polishing conditions based on the evaluation of the experimental silicon wafer in which only processing defects are evaluated. Can.

It is a process flow diagram showing an embodiment of a silicon wafer evaluation method of the present invention. It is a graph which shows the relationship of the number of repetition of the process-> treatment by hydrofluoric acid in the Example-> treatment by hydrofluoric acid, and the increase defect number. It is a SEM image which observed the wafer surface after washing | cleaning in an Example (A), and the SEM image of the defect detected by the (B) comparative example.

  As described above, in the conventional evaluation method of a silicon wafer, there is a problem that a crystal-induced defect occurs and a processing defect such as polishing can not be evaluated.

  The inventors of the present invention have conducted intensive studies to solve the above problems, and as a result, oxidation treatment with ozone water and hydrofluoric acid under the condition that the oxide film formed on the surface of the silicon wafer is not completely removed. A cleaning process alternately repeating oxide film removal processing and surface defect measurement are performed on the silicon wafer after the cleaning process to measure an increase defect increased with respect to a defect measured in the front surface defect measurement process. If the silicon wafer is evaluated on the basis of the measurement results of the increase defects after each cleaning step by repeating the increase defect measurement step a plurality of times alternately, only defects due to processing are not revealed in the cleaning step but crystal defects are apparent. It has been found that the present invention can be realized and only defects caused by processing such as polishing can be evaluated.

That is, the present invention is a method of evaluating a silicon wafer,
A front surface defect measurement step of performing surface defect measurement in advance on the silicon wafer;
A cleaning step of alternately repeating the oxidation treatment with ozone water and the oxide film removal treatment with hydrofluoric acid under the condition that the oxide film formed on the surface of the silicon wafer is not completely removed from the silicon wafer;
The surface defect measurement is performed on the silicon wafer after the cleaning step, and the increase defect measurement step of measuring an increase defect increased with respect to the defect measured in the front surface defect measurement step,
A method of evaluating a silicon wafer is provided, wherein the cleaning step and the increase defect measuring step are alternately repeated plural times, and the silicon wafer is evaluated based on the measurement result of the increase defect after each cleaning step. .

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

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

  First, a front surface defect measurement step of performing surface defect measurement in advance on the silicon wafer to be evaluated is performed (FIG. 1 (a)). For example, it can carry out using Surfscan SP5 by KLA-Tencor. Since the processing defects hardly have a particle size larger than 40 nm, a measured particle size of 40 nm or less is sufficient.

  Next, a cleaning step is performed by alternately repeating the oxidation treatment with ozone water and the oxide film removal treatment with hydrofluoric acid under the condition that the oxide film formed on the surface of the silicon wafer is not completely removed (FIG. 1 (b)) . It is preferable to perform this washing step with a single wafer type washing apparatus.

  The cleaning step (b) is a step of eliciting processing defects such as polishing. By removing the oxide film with hydrofluoric acid without completely removing the oxide film and re-oxidizing the wafer surface with ozone water, only the processing defects such as polishing become apparent without revealing the defects caused by the crystal. It can be done.

  According to the conventional SC1-RT method (for example, JP-A-2000-208578) or the conventional method for evaluating the quality of a wafer by ozone water and HF treatment, processing defects such as polishing can not be evaluated, but in the present invention, By performing cleaning repeatedly by using ozone water and hydrofluoric acid without completely removing the oxide film, it is possible to reveal and evaluate only defects caused by processing without revealing defects caused by crystals. It becomes possible. In addition, cleaning can be performed without deteriorating the surface roughness of the wafer, and measurement with a small particle diameter is possible.

  Thus, it becomes possible to evaluate only a processing defect by making only a processing defect such as polishing or the like apparent.

  The reason why only processing defects such as polishing can be revealed without revealing defects caused by crystals in the cleaning step (b) in the present invention is as follows. The processing defects are distorted layers in the wafer at the time of processing such as polishing and become a deteriorated layer. The oxide film of the wafer is removed by hydrofluoric acid, but the oxide film in the process-deteriorated area has an etching rate different from that of the surrounding oxide film, and it is manifested by alternately repeating the treatment with ozone water and the treatment with hydrofluoric acid. Will be This is because by performing an etching process to leave an oxide film with hydrofluoric acid, a difference occurs between the oxide film thickness of the process-altered layer and the surrounding area (the oxide film of the process-altered layer is thick), and it is oxidized by ozone water. This is because the difference becomes more remarkable by repeatedly performing the process of re-forming the film (returning the oxide film thickness uniformly). When the oxide film is completely removed, the oxide film portion of the damaged layer is also removed, and even if the ozone water treatment and the hydrofluoric acid treatment are repeated, there is no oxide film, so there is no difference in the oxide film thickness. The actualization does not occur and the defect evaluation due to processing becomes impossible.

  In addition, as in the present invention, the etching amount can be reduced by repeating the ozone water and hydrofluoric acid treatment without removing the oxide film completely, so that the oxide film is always left and the crystal defects such as oxygen precipitates and metals can be reduced. It does not reveal defects such as pits due to contamination.

  On the other hand, in the conventional SC 1 -RT method, not only processing defects but also crystal defects such as oxygen precipitates become apparent as a result of the realization by performing a large amount of etching.

  Also, the conventional quality evaluation method for wafers by ozone water and HF treatment includes the step of removing (stripping) all natural oxide films, and by completely removing the oxide films using ozone water and hydrofluoric acid. It is possible to evaluate without deteriorating the surface roughness, but with this method, crystal defects also become apparent when the natural oxide film is removed 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 form a natural oxide film, the concentration is preferably 5 ppm or more, and preferably 30 ppm or less from the viewpoint of substantially practical concentration. Moreover, it is preferable to set the processing time by ozone water per time to 10 seconds or more, in order to produce | generate a natural oxide film.

  The hydrofluoric acid concentration is not particularly limited, but preferably 0.1 to 1.0%. If it is 0.1% or more, it is preferable because concentration control can be performed accurately. Further, in order to control the film thickness of the natural oxide film, it is preferable to be 1.0% or less. Further, the hydrofluoric acid treatment time per one operation is preferably about 2 seconds to 20 seconds. If it is 2 seconds or more, the hydrofluoric acid supplied to the wafer is common, and if it is 20 seconds or less, it is preferable because the oxide film can be surely removed and the oxide film removing process can be performed.

  The number of repetitions of the oxidation treatment with ozone water and the oxide film removal treatment with hydrofluoric acid is preferably about 5 to about 50 times. If the number of repetitions is five or more, processing defects can be made to appear reliably. Moreover, if it is 50 times or less, since a washing | cleaning process time can be restrained and a throughput goes up, it is preferable. Furthermore, if it is 50 times or less, since it can evaluate, without deteriorating the surface roughness of a silicon wafer, it is preferable. Also, it is sufficient to be able to grasp the processing quality trend of the wafer without repeating it more than 50 times.

  Subsequently, surface defect measurement is performed on the silicon wafer after the cleaning step (b), and an increase defect measuring step (c) for measuring an increased defect relative to the defect measured in the front surface defect measuring step (a) I do.

  In this increased defect measuring step (c), the number of only increased defects relative to the defects measured in the front surface defect measuring step (a) is measured. The measurement can be carried out, for example, by measuring the same point coordinates using Surfscan SP5 manufactured by KLA-Tencor as in the front surface defect measurement step, to measure the increased number of only the increased defects.

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

  As described above, the cleaning step (b) and the increase defect measurement step (c) are alternately performed a plurality of times, and the silicon wafer is evaluated based on the measurement result of the increase defect (the inclination of the increase defect or the number of increase defects). Only processing defects such as polishing can be evaluated, excluding crystal-induced defects and particles generated in cleaning and the like.

  Under favorable processing conditions such as polishing, defects due to processing are not generated (less), so even if the cleaning step (b) and the increase defect measurement step (c) are repeated, the increase slope of increase defects is small and increases The number of defects is small. On the other hand, if the quality of the polishing process is poor, defects resulting from the processing occur, so if the cleaning and the surface defect measurement are repeated, the inclination of the increase in the increase of defects increases and the number of increase defects increases. By evaluating the polishing processing quality based on the inclination or the number of increased defects, it is possible to confirm the processing state at that time.

  That is, when the linear approximation of the increase defect is taken, the larger the inclination or the increase in the number of increase defects, the more the potential defect is included and the processing quality becomes worse.

  As described above, according to the present invention, the deterioration of the surface roughness of the wafer and the adhesion of particles and the like are suppressed only by repeatedly performing cleaning without completely removing the oxide film using ozone water and hydrofluoric acid. Instead, only processing defects such as polishing can be revealed without revealing defects caused by crystals. Further, by observing the increasing tendency of the increased defects measured after each cleaning step, it is possible to evaluate only defects caused by processing such as polishing excluding particles caused by crystal-induced defects and particles generated by cleaning and the like. In addition, it has become possible to evaluate defects in micro areas that have never been available.

  Moreover, the evaluation method of the above-mentioned silicon wafer can be applied to a method of mirror-polishing the silicon wafer before mirror-polishing to produce a silicon wafer as a product. 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 to specify in advance mirror polishing conditions in mirror polishing. Mirror polishing is performed under specified mirror polishing conditions to manufacture a silicon wafer as a product. Specifically, the silicon wafer is manufactured as follows.

  First, a test silicon wafer before mirror polishing is prepared. Next, mirror polishing is performed on the experimental silicon wafer before mirror polishing under predetermined mirror polishing conditions. The front surface defect measurement step, the cleaning step, and the increase defect measurement step are performed on the experimental silicon wafer mirror-polished in this manner, as in the evaluation method of the silicon wafer described above (FIG. 1 (a) c) see Specifically, each process is performed as follows. First, a front surface defect measurement step of performing surface defect measurement in advance is performed on the experimental silicon wafer subjected to mirror polishing. Next, for the experimental silicon wafer, the oxidation treatment with ozone water and the oxide film removal treatment with hydrofluoric acid under the condition that the oxide film formed on the surface of the experimental silicon wafer is not completely removed are alternately repeated. Perform the washing process. Next, surface defect measurement is performed on the experimental silicon wafer after the cleaning step, and an increase defect measurement step is performed to measure an increase defect of the defects measured in the front surface defect measurement step.

  The above cleaning step and the increase defect measuring step are alternately repeated plural times, and the experimental silicon wafer is evaluated based on the measurement result of the increase defect after each cleaning step. Furthermore, based on the evaluation of the experimental silicon wafer, mirror-polishing conditions in mirror-polishing such that the polishing quality after mirror-polishing the silicon wafer before mirror-polishing becomes desired polishing quality are specified. Under the mirror polishing conditions specified here, the silicon wafer before mirror polishing is mirror-polished to manufacture a silicon wafer as a product.

  In mirror-polished silicon wafers polished under the polishing conditions (less) where no processing defects occur after mirror polishing, the slope of the increase in increased defects is small even if the cleaning step (b) and the increase defect measurement step (c) are repeated. , The number of increased defects is small. On the other hand, if the quality of the polishing process is poor, defects resulting from the processing occur, so if the cleaning and the surface defect measurement are repeated, the inclination of the increase in the increase of defects increases and the number of increase defects increases. By evaluating the polishing quality of the experimental silicon wafer based on the inclination or the number of defects increased, the desired polishing quality can be obtained by performing mirror polishing under any mirror polishing condition on the silicon wafer before mirror polishing. Can be identified.

  More specifically, it is possible to select a mirror polishing condition such that there is no or small inclination when linear approximation of increasing defects is taken. For example, mirror polishing conditions should be set so that the number of defects increasing per 10 repetitions of hydrofluoric acid → ozone water in the flow shown in FIG. 1 averages 10 or less, 5 or less, or 1 or less. Can.

  EXAMPLES The present invention will be more specifically described below with reference to examples and comparative examples, but the present invention is not limited to these examples.

(Example)
The front surface defect measurement was performed using the silicon wafer which was finally polished under different polishing conditions (polishing conditions 1 to 4) and the cleaning was completed (FIG. 1 (a)). The wafer whose front surface defect was measured was cleaned by alternately repeating the oxidation treatment with ozone water and the oxide film removal treatment with hydrofluoric acid (FIG. 1 (b)).

  The cleaning conditions are: ozone water concentration 10 ppm, ozone water treatment time per time 20 seconds, hydrofluoric acid concentration 0.3%, hydrofluoric acid treatment time per time 5 seconds, and the flow shown in FIG. Washing was performed with the number of repetitions of ozone water being five times, and then dried. In any hydrofluoric acid treatment, the oxide film was removed while leaving the thickness on the wafer surface.

  Subsequently, surface defect measurement was performed on the silicon wafer after the cleaning step, and an increase defect increased with respect to the defect measured in the front surface defect measurement step (a) was measured (FIG. 1 (c)). In the front surface defect measurement and the increase defect measurement, measurement was performed with a particle diameter of 19 nm or more using Surfscan SP5 manufactured by KLA-Tencor, and by measuring the same point coordinates, only the increase defect was measured.

  Repeat the cleaning process and the increase defect measurement process until the total number of repetitions of the treatment with ozone water → the treatment with hydrofluoric acid is 50 times (that is, until the number of repetitions of the cleaning process and the increase defect measurement process is 10) went.

  The total number of repetitions of treatment with ozone water → treatment with hydrofluoric acid and the number of increased defects are summarized in Table 1 with the number of defects increased as the number of increased defects with respect to the result of front surface defect measurement after each cleaning step. Indicated. In addition, the relationship between the total number of repetitions of the treatment with ozone water → the treatment with hydrofluoric acid and the number of increased defects is plotted in a graph in FIG. Based on Table 1 and FIG. 2, the increase slope of the increase defect or the increase amount of the defect was evaluated.

  In addition, when the wafer surface after cleaning was observed by SEM, it was found that no crystal defects were apparent on the wafer surface, and only the processing defects as shown in FIG. It turned out that evaluation is possible.

  As shown in FIG. 2, under the polishing conditions 1 to 4, the inclination of the increase in the increase in defects is different for each of the polishing conditions, and since the inclination of the increase in the polishing condition 1 is almost zero, defects due to processing occur. It was found that the polishing quality was good. Further, it was found that in the polishing conditions 2 to 4, as the inclination of the increase is larger, that is, the polishing quality is worse in the order of the polishing condition 4, the polishing condition 3 and the polishing condition 2.

(Comparative example)
The silicon wafer was evaluated by the evaluation method according to SC1-RT method described in JP-A-2000-208578. Specifically, using a processing solution consisting of ammonia, hydrogen peroxide and water, the silicon wafer surface was etched to detect defects. However, it was the particles and crystal defects mainly as shown in FIG. 3 (B) that were detected by the processing. Further, even if Surfscan SP5 manufactured by KLA-Tencor Co., Ltd. was used, measurement could not be made at particle diameters of 19 nm or more because the surface roughness was deteriorated.

  The present invention is not limited to the above embodiment. The above embodiment is an exemplification, and it has substantially the same configuration as the technical idea described in the claims of the present invention, and any one having the same function and effect can be used. It is included in the technical scope of the invention.

Claims (6)

It is an evaluation method of a silicon wafer, and
A front surface defect measurement step of performing surface defect measurement in advance on the silicon wafer;
A cleaning step of alternately repeating the oxidation treatment with ozone water and the oxide film removal treatment with hydrofluoric acid under the condition that the oxide film formed on the surface of the silicon wafer is not completely removed from the silicon wafer;
The surface defect measurement is performed on the silicon wafer after the cleaning step, and the increase defect measurement step of measuring an increase defect increased with respect to the defect measured in the front surface defect measurement step,
A method of evaluating a silicon wafer, comprising alternately repeating the cleaning step and the increase defect measurement step a plurality of times, and evaluating the silicon wafer based on the measurement result of the increase defect after each cleaning step.   The oxide film removal process with hydrofluoric acid under the condition that the oxide film is not completely removed is performed with a hydrofluoric acid concentration of 0.1 to 1.0% and a processing time of 2 seconds to 20 seconds. The evaluation method of the silicon wafer as described in 1.   The method for evaluating a silicon wafer according to claim 1 or 2, wherein the cleaning step is alternately repeated with the oxidation treatment with ozone water and the oxide film removal treatment with hydrofluoric acid five times or more. .   The evaluation method of a silicon wafer according to any one of claims 1 to 3, wherein a mirror-polished wafer is used as the silicon wafer.   The silicon wafer according to any one of claims 1 to 4, wherein defects caused by processing of the silicon wafer are evaluated based on the measurement results of the increased defects after the cleaning steps. Evaluation method. A method of manufacturing a silicon wafer to be a product by mirror-polishing a silicon wafer before mirror-polishing,
Preparing an experimental silicon wafer before mirror polishing;
Mirror-polishing the experimental silicon wafer before mirror-polishing under predetermined mirror-polishing conditions;
A front surface defect measurement step of performing surface defect measurement in advance on the experimental silicon wafer;
Cleaning the silicon wafer for the experiment alternately by the oxidation treatment with ozone water and the oxide film removal treatment with hydrofluoric acid under the condition that the oxide film formed on the surface of the silicon wafer for experiment is not completely removed Process,
Carrying out surface defect measurement on the experimental silicon wafer after the cleaning step and measuring an increase defect for the defects measured in the front surface defect measurement step;
The cleaning step and the increase defect measuring step are alternately repeated plural times, and the experimental silicon wafer is evaluated based on the measurement result of the increase defect after each cleaning step,
Based on the evaluation of the experimental silicon wafer, the mirror polishing condition in the mirror polishing is specified such that the polishing quality after the mirror polishing is performed on the silicon wafer before the mirror polishing becomes a desired polishing quality,
A method of manufacturing a silicon wafer, comprising: performing mirror polishing on the silicon wafer before the mirror polishing under the specified mirror polishing conditions to manufacture a silicon wafer to be the product.