JP5018741B2 - Semiconductor wafer evaluation method and semiconductor wafer evaluation apparatus - Google Patents

Description

  The present invention relates to a semiconductor wafer evaluation method and a semiconductor wafer evaluation device, and more particularly to a semiconductor wafer evaluation method and a semiconductor wafer evaluation device for evaluating a BMD density distribution.

  With the recent high integration of semiconductor elements, evaluation of internal defects in semiconductor wafers has become important. In particular, BMD (Bulk Micro Defect) is an important parameter indicating the gettering capability of a Si wafer, and is important as quality data at the time of development and shipping inspection. Conventionally, as a method for detecting BMD of a semiconductor wafer, a selective etching method and a light diffusion method are widely used.

  However, the selective etching method is a destructive method in which the inside of a semiconductor wafer to be evaluated is cleaved or obliquely polished, and the cleaved surface is etched, and recently there is a problem in terms of the influence of the etching solution on the environment. . On the other hand, the light diffusion method is a method in which laser light is incident from the wafer surface and the light is recognized by detecting scattered light due to crystal defects existing directly under the surface, and the size of the light scatterer is very small. Is sufficiently detectable, and there is an advantage that small defects such as grown-in defects and oxygen precipitates in the crystal can be evaluated. However, light scattering occurs not only within the sample but also at the surface, so if the surface is rough, there is a step due to the device pattern, or if there are particles, dirt, etc., surface scattering However, the scattered light cannot be separated and the observation of the defect is very difficult.

Further, in these methods, the range that can be measured at one time is small, and it is difficult to measure the BMD density on the entire surface of the semiconductor wafer, and even if it can be done, a very long time is required.
Therefore, a surface layer defect detection method using the strong excitation microscopic PL method has been developed (see, for example, Patent Document 1). This method can detect a defect with almost no influence of light scattering due to surface roughness or the like, and is very excellent as a method for evaluating a surface layer defect. However, since the detection sensitivity is low unless it is an electro-optically active defect in principle, there is a drawback that it is not very effective for detecting BMD.

Japanese Patent Laid-Open No. 11-274257

  SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is possible to acquire the BMD density on the entire surface of the semiconductor wafer in a short time, and to evaluate the BMD density distribution with high accuracy and the semiconductor wafer evaluation apparatus. The purpose is to provide.

  In order to solve the above-mentioned problems, the present invention is a method for evaluating the BMD density in a semiconductor wafer, which measures a strong excitation microscopic PL value on the entire surface of the semiconductor wafer, and then at a plurality of locations in the surface of the semiconductor wafer. A BMD density is measured, a relational expression between the strong excitation microscopic PL value at the same position of the semiconductor wafer and the measured BMD density is obtained, and a strong excitation microscopic PL value of the entire surface of the semiconductor wafer is obtained from the obtained relational expression. A method for evaluating a semiconductor wafer is provided, wherein the BMD density distribution is evaluated by quantifying the BMD density on the entire surface of the semiconductor wafer.

  In this way, the strong excitation microscopic PL value on the entire surface of the semiconductor wafer and the BMD density at a plurality of locations in the semiconductor wafer surface are measured, and the relational expression between the strong excitation microscopic PL value and the BMD density at the same position on the semiconductor wafer is obtained. By quantifying the BMD density on the entire surface of the semiconductor wafer from the relational expression, the BMD density distribution on the entire surface of the semiconductor wafer can be evaluated only by measuring the BMD density only at an arbitrary representative point in the semiconductor wafer surface. . Therefore, the time required for measuring the BMD density can be shortened, and the BMD density distribution on the entire surface of the semiconductor wafer can be evaluated in a short time. In addition, by obtaining a relational expression between the strong excitation microscopic PL value and the actually measured BMD density, and quantifying the BMD density on the entire surface of the semiconductor wafer from the relational expression, an accurate BMD density can be obtained. The density distribution can be evaluated with high accuracy.

In this case, the measurement of the strong excitation microscopic PL value on the entire surface of the semiconductor wafer can be performed at an arbitrary interval that minimizes the spot diameter of the laser used for the measurement.
Thus, the measurement interval can be changed according to the specifications of the apparatus used for measuring the strong excitation microscopic PL value. Specifically, considering the measurement accuracy of the BMD density to be performed later, it is possible to change the measurement interval of the strong excitation microscopic PL value so as to cover the measurement location and obtain a BMD density distribution with a desired accuracy. is there. Therefore, by setting the measurement interval of the strong excitation microscopic PL value to an arbitrary interval wider than the laser spot diameter, it is possible to prevent the laser spots from overlapping each other, shorten the measurement time, and achieve the desired accuracy in a short time. BMD density distribution can be evaluated.

In this case, the BMD density can be measured by using a selective etching method or a light scattering method.
As described above, by measuring the BMD density using the selective etching method or the light scattering method, the BMD density can be measured at an arbitrary position in the semiconductor wafer surface. Further, by using the selective etching method or the light scattering method, the BMD density can be measured using the existing equipment without preparing new equipment. Therefore, as a result, the present invention can evaluate the BMD density distribution with high accuracy without cost.

  According to the present invention, there is provided an apparatus for evaluating a BMD density in a semiconductor wafer, at least a strongly excited microscopic photoluminescence defect detecting apparatus for measuring a strongly excited microscopic PL value on the entire surface of the semiconductor wafer, and a plurality of the semiconductor wafers. A BMD measuring means for measuring the BMD density of the location, and an analytical computer for inputting the measured strong excitation microscopic PL value and the BMD density, and using the analytical computer, at the same position of the semiconductor wafer A relational expression between the strong excitation microscopic PL value and the measured BMD density is obtained, and the BMD density on the entire surface of the semiconductor wafer is quantified using the strong excitation microscopic PL value on the entire surface of the semiconductor wafer from the obtained relational expression. The present invention provides an evaluation apparatus for a semiconductor wafer characterized by evaluating a BMD density distribution.

  As described above, the semiconductor wafer evaluation apparatus of the present invention includes a strongly excited microscopic photoluminescence defect detecting device that measures the strongly excited microscopic PL value on the entire surface of the semiconductor wafer, and a BMD measuring unit that measures the BMD density at a plurality of locations on the semiconductor wafer. And a device for measuring a strongly excited microscopic PL value on the entire surface of the semiconductor wafer and a BMD density at a plurality of locations in the surface of the semiconductor wafer using the strongly excited microscopic photoluminescence defect detecting device and the BMD measuring means. In addition, an analysis computer for inputting the measured value is also provided. With this analysis computer, a relational expression between the strong excitation microscopic PL value and the BMD density at the same position of the semiconductor wafer is obtained, and the semiconductor wafer is obtained from the relational expression. By quantifying the BMD density on the entire surface, it is possible to obtain an apparatus that can evaluate the BMD density distribution on the entire surface of the semiconductor wafer only by measuring the BMD density only at an arbitrary representative point in the semiconductor wafer surface. Therefore, the time required for measuring the BMD density can be shortened, and the apparatus can evaluate the BMD density distribution on the entire surface of the semiconductor wafer in a short time. In addition, by using a computer for analysis, a relational expression between the strong excitation microscopic PL value and the actually measured BMD density is obtained, and the BMD density on the entire surface of the semiconductor wafer is quantified from the relational expression to obtain an accurate BMD density. Can be obtained, and a BMD density distribution can be evaluated with high accuracy.

In this case, the strongly excited microscopic photoluminescence defect detecting device preferably measures the strongly excited microscopic PL value of the entire surface of the semiconductor wafer at an arbitrary interval with the laser spot diameter of the device being minimized. Item 5).
As described above, the strong excitation microscopic photoluminescence defect detection apparatus can change the measurement interval of the strong excitation microscopic PL value according to the specifications of the apparatus. At this time, in consideration of the measurement accuracy of the BMD density of the BMD measurement means, the measurement interval of the strong excitation microscopic PL value is changed so as to cover the measurement location, and a BMD density distribution with a desired accuracy is obtained. Is possible. Therefore, by measuring the strong excitation microscopic PL value at an arbitrary interval wider than the laser spot diameter of the apparatus, the apparatus can shorten the measurement time and evaluate the BMD density distribution with a desired accuracy in a short time. It can be.

The BMD measuring means is preferably a means using a selective etching method or a light scattering method.
As described above, by using a selective etching method or a light scattering method as the BMD measuring means, the BMD density can be measured at an arbitrary position in the semiconductor wafer surface. In addition, by using the selective etching method or the light scattering method for the BMD measuring means, it is possible to use the existing equipment as it is without preparing a new equipment, so that the BMD measuring means can be obtained. Therefore, it can be set as the apparatus which can evaluate exact BMD density distribution with high precision, without costing.

  As described above, the semiconductor wafer evaluation method of the present invention measures the strong excitation microscopic PL value on the entire surface of the semiconductor wafer and the BMD density at a plurality of locations in the semiconductor wafer surface, and the strong excitation microscopic at the same position on the semiconductor wafer. A relational expression between the PL value and the BMD density is obtained, and the BMD density on the entire surface of the semiconductor wafer is quantified from the relational expression. As a result, the BMD density distribution on the entire surface of the semiconductor wafer can be evaluated only by measuring the BMD density only at an arbitrary representative point in the semiconductor wafer surface. Therefore, the BMD density distribution can be evaluated with high accuracy in a short time. Then, the semiconductor wafer evaluation apparatus of the present invention uses a strongly excited microscopic photoluminescence defect detecting device and a BMD measuring means, and a strongly excited microscopic PL value on the entire surface of the semiconductor wafer and a BMD density at a plurality of locations in the surface of the semiconductor wafer. The measurement data is input to the analysis computer, and the analytical computer determines the relational expression between the strong excitation microscopic PL value and the BMD density at the same position of the semiconductor wafer, and from the relational expression, the entire surface of the semiconductor wafer is obtained. By digitizing the BMD density, it is possible to provide an apparatus that can evaluate the BMD density distribution with high accuracy in a short time.

Hereinafter, the present invention will be described more specifically.
As described above, in the selective etching method and the light diffusion method, it is difficult to measure the BMD density on the entire surface of the semiconductor wafer. Further, even when the strong excitation microscopic PL method is used, there is a drawback that it is not very effective for detecting BMD.

  Therefore, the present inventors quantify the BMD density on the entire surface of the semiconductor wafer from the relationship between the strong excitation microscopic PL value measured by the strong excitation microscopic PL method and the BMD density measured by the selective etching method or the light diffusion method. The idea is to evaluate the BMD density distribution of the entire semiconductor wafer by simply measuring the BMD density at several locations on the semiconductor wafer surface, and the strong excitation microscopic PL value on the entire surface of the semiconductor wafer and any representative in the semiconductor wafer surface. The BMD density of the points was measured, the relational expression of both at the same position of the semiconductor wafer was obtained, and the BMD density distribution on the entire surface of the semiconductor wafer was evaluated.

  As a result, it was found that the relational expression between the strong excitation microscopic PL value and the BMD density can be expressed by a straight line. Therefore, it was found that the relational expression between the strong excitation microscopic PL value and the BMD density can be derived by measuring the BMD density of at least two points.

  In addition, since the relationship between the strong excitation microscopic PL value and the BMD density can be obtained only by measuring the BMD density only at an arbitrary representative point in the semiconductor wafer surface, the time required for actually measuring the BMD density is shortened. I found out that I can do it.

  Furthermore, from the relational expression between the strong excitation microscopic PL value and the actually measured BMD density, the BMD density on the entire surface of the semiconductor wafer was quantified using the strong excitation microscopic PL value on the entire surface of the semiconductor wafer, and was actually measured. It was found that a highly accurate evaluation using an accurate BMD density distribution that reflects the value of the BMD density can be performed.

  Further, since the relational expression between the strong excitation microscopic PL value and the actually measured BMD density is obtained, the measurement interval of the strong excitation microscopic PL value is changed in consideration of the measurement accuracy of the BMD density. It was found that a BMD density distribution can be obtained. Specifically, by setting the measurement interval of the strong excitation microscopic PL value to an arbitrary interval wider than the spot diameter of the laser of the apparatus, the measurement time is shortened and a BMD density distribution with a desired accuracy can be obtained in a short time. I was able to.

  In addition, if the BMD density can be measured at any point in the semiconductor wafer surface, either the selective etching method or the light scattering method can be used, so existing equipment can be used as it is. I found out that there was no cost.

The present invention has been completed based on the above findings and findings, and the present invention will be described below in more detail with reference to the drawings. However, the present invention is not limited to these.
Here, FIG. 1 is a diagram schematically showing a configuration example of the semiconductor wafer evaluation apparatus of the present invention.

  This semiconductor wafer evaluation apparatus 10 includes a strongly excited microscopic photoluminescence defect detecting apparatus 11 that measures a strongly excited microscopic PL value on the entire surface of the semiconductor wafer and a BMD measuring means 12 that measures the BMD density at a plurality of locations in the semiconductor wafer surface. I have.

  Furthermore, the computer 13 for analysis which inputs the strong excitation microscopic PL value measured with the strong excitation microphotoluminescence defect detection apparatus 11 and the BMD density measured with the BMD measuring means 12 is also provided, and using this analytical computer 13, The relational expression between the strong excitation microscopic PL value and the BMD density is obtained, and based on the relational expression, the input strong excitation microscopic PL value is recalculated, and the BMD density in a necessary portion in the semiconductor wafer surface is quantified. To do.

  As described above, since the BMD density of the semiconductor wafer using the BMD measuring unit 12 is actually measured only at arbitrary representative points as a plurality of locations on the surface of the semiconductor wafer, the measurement of the in-plane BMD density is possible. Can be shortened. Therefore, it can be set as the apparatus which can evaluate BMD density distribution of the whole semiconductor wafer in a short time. Further, by using the analysis computer 13, a relational expression between the strong excitation microscopic PL value and the actually measured BMD density is obtained, and the BMD density on the entire surface of the semiconductor wafer is quantified from the relational expression, thereby obtaining an accurate BMD. The device can obtain the density and can evaluate the BMD density distribution with high accuracy.

Moreover, the said apparatus can measure the strong excitation microscopic PL value of the whole surface of a semiconductor wafer by the strong excitation microphotoluminescence defect detection apparatus 11 by the arbitrary space | interval which made the spot diameter of the laser the minimum.
Thus, the strong excitation microscopic photoluminescence defect detection apparatus 11 can change the measurement interval of the strong excitation microscopic PL value according to the specifications of the apparatus. Further, in consideration of the measurement accuracy of the BMD density of the BMD measuring means 12, the measurement interval of the strong excitation microscopic PL value is changed so as to cover the measurement location, and a BMD density distribution with a desired accuracy is obtained. Is possible. Therefore, the measurement time of the strong excitation microscopic PL value can be shortened, and a more accurate BMD density distribution can be evaluated with higher accuracy.

The strong excitation microscopic photoluminescence method used in the present invention is to narrow the spot diameter at the sample position of the excitation laser to 1 to 2 μm (the diameter is about 0.1 to 1 mm in the normal PL method), and the laser power is also the sample position The PL method is performed under an excitation condition of 20 to 100 mW which is several to several tens of times higher than that of the normal PL method. This excitation conditions, the energy density of the excitation laser is high about 10 ⁵ times the normal PL method. Usually, under the excitation condition of the PL method, the carrier diffusion length is as long as several hundred μm, and the spatial resolution of PL light (band edge emission) is also several hundred μm. On the other hand, in the strong excitation microscopic PL method, by using the above strong excitation conditions, the carrier diffusion length is suppressed to the order of several μm, and PL light measurement with high spatial resolution (˜1 μm) becomes possible. Here, the band edge emission intensity in the strong excitation microscopic PL method is expressed by the following equation.
I _b ∝n _ex ² τ (where I _{b is the} band edge emission intensity, n _{ex is the} injected carrier concentration, τ is the lifetime)

Further, in the semiconductor wafer evaluation apparatus of the present invention, the BMD measuring means 12 is preferably a means using a selective etching method or a light scattering method.
As described above, by using a selective etching method or a light scattering method as the BMD measuring means, the BMD density can be measured at an arbitrary position in the semiconductor wafer surface. In addition, by using the selective etching method or the light scattering method for the BMD measuring means, it is possible to use the existing equipment as it is without preparing a new equipment, so as to be a BMD measuring means. Therefore, it can be set as the apparatus which can evaluate exact BMD density distribution with high precision, without costing.

The selective etching method used in the present invention conforms to a silicon crystal defect testing method by the Japanese Industrial Standard JIS H 0609-1994 selective etching method.
In addition, the light scattering method used in the present invention is a method capable of nondestructively observing defects in a crystal using infrared rays that easily transmit through a silicon crystal. In the infrared tomography method, an infrared laser beam is incident on a crystal, and a defect is detected by detecting scattered light due to a crystal defect. The intensity of the scattered light is I∝ (1 / 4πλ ² ) ² · [(ε-ε _Si ) V] ² · I ₀ (where I: scattered light intensity, I ₀ : incident light intensity, λ: wavelength, ε : Dielectric constant of defects, ε _Si : dielectric constant of _Si , V: volume of defects), which is proportional to the square of the volume of the defects. As typical measurement apparatuses, MO-401, MO-441, etc. manufactured by Raytec are listed.

  Next, although an example of the semiconductor wafer evaluation method of the present invention will be described in more detail with reference to the drawings, the present invention is not limited thereto.

First, the strong excitation microscopic PL value of the entire surface of the semiconductor wafer is measured using the strong excitation microphotoluminescence defect detection apparatus 11 of the semiconductor wafer evaluation apparatus 10 as shown in FIG. The image information diagram of the strong excitation microscopic PL value obtained at this time is shown in FIG. 2 as the intensity of the strong excitation microscopic PL value is shaded on the image.
Here, FIG. 3 shows the strong excitation microscopic PL value in the solid line portion in FIG.

Next, the BMD density is measured using the BMD measuring means 12 in FIG. 1 at a plurality of locations in the solid line portion in FIG. Here, the measurement location of BMD density is shown in FIG.
The strong excitation microscopic PL value and the BMD density measured as described above are respectively input to the analyzing computer 13 in FIG. 1 to obtain a relational expression therebetween. FIG. 5 shows the result of obtaining the relationship between the strong excitation microscopic PL value (four points in FIG. 3) and the measured BMD density at the same position of the semiconductor wafer at this time.

  At this time, in FIG. 5, the BMD density at four points in the semiconductor wafer surface is measured to obtain a relational expression with the strong excitation microscopic PL value. In this way, the relation between the two can be expressed by a straight line. it can. Therefore, since the relationship between the two can be derived by measuring the BMD density of at least two points, the time required for measuring the BMD density can be shortened.

Subsequently, by using the analyzing computer 13, the strength of the strong excitation microscopic PL value on the entire surface of the semiconductor wafer is recalculated from the relational expression as shown in FIG. Output a numerical value.
As a result, an accurate BMD density reflecting the actually measured BMD density value can be obtained from the strong excitation microscopic PL value on the entire surface of the semiconductor wafer, and a highly accurate evaluation can be performed using this BMD density distribution. can do.

  In addition, in the measurement of the strong excitation microscopic PL value on the entire surface of the semiconductor wafer, the measurement interval of the strong excitation microscopic PL value can be changed in consideration of the measurement accuracy of the BMD density to be performed thereafter. Specifically, by setting the measurement interval of the strong excitation microscopic PL value to an arbitrary interval wider than the spot diameter of the laser of the apparatus, the measurement time of the strong excitation microscopic PL value is shortened, and the desired accuracy can be achieved in a short time. BMD density distribution can be obtained.

Further, the BMD density (4 points) shown in FIG. 5 shows the result obtained when the selective etching method is used. However, it is possible to measure the BMD density at any point in the semiconductor wafer surface. For example, a light scattering method or other methods can be used.
Thus, by using the selective etching method or the light scattering method, the BMD density can be measured using the existing equipment without preparing new equipment. Therefore, the BMD density distribution can be evaluated with high accuracy without cost.

Next, the present invention will be described more specifically with reference to Examples and Comparative Examples of the present invention, but the present invention is not limited to these.
(Example)
A sample subjected to precipitation heat treatment at 800 ° C. for 4 hours, and further at 1000 ° C. for 16 hours in a dry oxygen atmosphere to form BMD on a silicon wafer having a diameter of 300 mm and an N-type <100> was used for evaluation. . In addition, the dopant of this N-type wafer was antimony.
Below, the procedure of evaluation of BMD density distribution using the said sample is demonstrated.

  First, using a semiconductor wafer evaluation apparatus 10 as shown in FIG. 1, the strong excitation microscopic PL value of the entire silicon wafer was measured by the strong excitation microphotoluminescence defect detection apparatus 11 in FIG. At this time, in order to obtain the BMD density distribution with as high accuracy as possible, the measurement interval of the strong excitation microscopic PL value was measured as the same as the laser spot diameter of the strong excitation microscopic photoluminescence defect detection device 11. The image information diagram of the measured strong excitation microscopic PL value is as shown in FIG. Further, the strong excitation microscopic PL value at the solid line portion in FIG. 2 at this time is as shown in FIG.

  Next, as the BMD measuring means 12 in FIG. 1, the BMD density at four locations in the solid line portion in FIG. 2 was measured using an apparatus using a selective etching method. Here, the measurement location of the BMD density at this time is as shown in FIG.

  Subsequently, the measured values of the strong excitation microscopic PL value and the BMD density were input to the analyzing computer 13 in FIG. 1 to obtain a relational expression therebetween. Here, the result of obtaining the relationship between the strong excitation microscopic PL value (four points in FIG. 3) and the measured value of the BMD density at the same position of the silicon wafer is as shown in FIG. The relational expression shown was obtained.

  Thereafter, using the analyzing computer 13, the intensity of the strong excitation microscopic PL value on the entire surface of the silicon wafer is recalculated from the relational expression shown in FIG. And the BMD density distribution of FIG. 6 was obtained from the numerical values.

(Comparative example)
Using a sample similar to the sample of the example, the BMD density in the semiconductor wafer surface was measured using only the apparatus using the selective etching method. In addition, the measurement location of the BMD density at this time was made into 4 places shown in FIG. 4, and 3 places between these. The measurement results of the BMD density at these seven points are shown as plots in FIG. FIG. 7 shows the relationship between the BMD densities obtained in Examples and Comparative Examples.

From FIG. 6, it can be seen that in the example, the BMD density distribution over the entire surface of the silicon wafer as well as a part within the surface of the silicon wafer could be obtained, and the entire surface of the silicon wafer could be evaluated. However, in the comparative example, the measurement of the BMD density at only seven locations in the silicon wafer surface requires a long time measurement as compared with the example.
That is, the time required to obtain the BMD density distribution of the example was almost the same as the case where the BMD density at a plurality of locations in the silicon wafer surface was measured. On the other hand, it is expected that enormous time is required to measure the BMD density on the entire surface of the silicon wafer by using the method of the comparative example and obtain the BMD density distribution. It is impossible to evaluate

  As described above, according to the semiconductor wafer evaluation method of the present invention, it is possible to evaluate the BMD density distribution with high accuracy in a short time only by measuring the BMD density only at an arbitrary representative point in the semiconductor wafer surface. . According to the semiconductor wafer evaluation apparatus of the present invention, the apparatus can evaluate the BMD density distribution with high accuracy in a short time.

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

It is a figure which shows typically the structural example of the evaluation apparatus of the semiconductor wafer of this invention. It is an example of the image information figure of strong excitation microscopic PL value. It is a figure which shows the strong excitation microscopic PL value in the continuous line part in FIG. It is a figure which shows the measurement location of the BMD density in a semiconductor wafer surface. It is a figure which shows the relationship between strong excitation microscopic PL value and BMD density. It is BMD density distribution obtained in the Example. It is a figure which shows the relationship of the BMD density obtained by the Example and the comparative example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Semiconductor wafer evaluation apparatus, 11 ... Strong excitation microphotoluminescence defect detection apparatus, 12 ... BMD measuring means, 13 ... Analysis computer.

Claims (6)

  A method for evaluating a BMD density in a semiconductor wafer, wherein a strong excitation microscopic PL value of the entire surface of the semiconductor wafer is measured, and then a BMD density at a plurality of locations in the surface of the semiconductor wafer is measured. A relational expression between the strong excitation microscopic PL value at the position and the measured BMD density is obtained, and the BMD density on the entire surface of the semiconductor wafer is calculated from the obtained relational expression using the strong excitation microscopic PL value on the entire surface of the semiconductor wafer. A method for evaluating a semiconductor wafer, characterized by quantifying and evaluating a BMD density distribution.   2. The method for evaluating a semiconductor wafer according to claim 1, wherein the measurement of the strong excitation microscopic PL value on the entire surface of the semiconductor wafer is performed by setting the measurement interval to an arbitrary interval that minimizes the spot diameter of the laser used for the measurement. .   The method for evaluating a semiconductor wafer according to claim 1, wherein the BMD density is measured using a selective etching method or a light scattering method.   An apparatus for evaluating a BMD density in a semiconductor wafer, comprising at least a strongly excited microscopic photoluminescence defect detecting apparatus for measuring a strongly excited microscopic PL value on the entire surface of the semiconductor wafer, and measuring a BMD density at a plurality of locations on the semiconductor wafer. BMD measurement means for performing analysis, and a computer for analysis for inputting the measured strong excitation microscopic PL value and BMD density, and using the analytical computer, the strong excitation microscopic PL value at the same position of the semiconductor wafer. And the measured BMD density, the BMD density distribution on the entire surface of the semiconductor wafer is quantified using the strong excitation microscopic PL value on the entire surface of the semiconductor wafer, and the BMD density distribution is evaluated. An apparatus for evaluating a semiconductor wafer, characterized in that:   5. The strong excitation microscopic photoluminescence defect detection apparatus measures a strong excitation microscopic PL value on the entire surface of the semiconductor wafer at an arbitrary interval that minimizes the laser spot diameter of the apparatus. The semiconductor wafer evaluation apparatus described in 1.   6. The semiconductor wafer evaluation apparatus according to claim 4, wherein the BMD measuring means is a means using a selective etching method or a light scattering method.

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