JP2006278515A - Method for evaluating semiconductor wafer and process for producing semiconductor wafer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for evaluating microroughness of semiconductor wafer surface easily in order to perform polishing and cleaning of a semiconductor wafer effectively during production thereof, and to provide a process for producing a semiconductor wafer by using that evaluation method. <P>SOLUTION: In the method for evaluating a semiconductor wafer, haze value of semiconductor wafer surface is measured previously for vertical irradiation/high angle light reception and/or oblique irradiation/low angle light reception, surface profile of the wafer is measured and its data converted into power spectrum, and then correlation of power spectral density of that power spectrum and the haze value for vertical irradiation/high angle light reception at space wavelength of 1 μm and/or correlation of power spectral density and the haze value for oblique irradiation/low angle light reception at space wavelength of 0.1 μm are determined. A process for producing a semiconductor wafer by evaluating the surface profile of wafer using that method and adjusting the polishing conditions and/or the cleaning conditions depending on the evaluation results is also provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a semiconductor wafer evaluation method and manufacturing method, and more particularly to a semiconductor wafer surface microroughness evaluation method and a semiconductor wafer manufacturing method using the evaluation method.

  The required quality of silicon wafers has become increasingly sophisticated due to the recent high integration and high precision of devices. In particular, improving the flatness and surface roughness of the silicon wafer surface improves the electrical characteristics of the device. It is necessary for.

  That is, it has been found that the microroughness on the wafer surface has an influence on the electrical characteristics of the device. For example, if the microroughness is large, the oxide film breakdown voltage decreases, and further, the microroughness is reduced in the channel below the gate oxide film. It is known that when it becomes larger, electron scattering occurs and the electron mobility becomes smaller. In particular, it has been found that haze, which has irregularities with a spatial wavelength of about 0.01 to 5 μm on the wafer surface, affects the reliability test of the electrical characteristics of the device, particularly the time-dependent dielectric breakdown characteristics (TDDB) of the oxide film. Yes.

  Therefore, in order to improve the electrical characteristics of future devices, it is necessary to improve the microroughness such as haze of the silicon wafer, and these improvement methods have been disclosed (for example, Patent Document 1).

On the other hand, waviness having irregularities with a spatial wavelength on the wafer surface of several millimeters to 20 mm is also a problem in photolithography, element separation, and the like in the device manufacturing process. On the other hand, it is disclosed that the surface shape of the back surface of the wafer is measured, the power spectral density is obtained therefrom, and the power spectral density at a spatial wavelength of 10 mm is set to 10 μm ³ or less (Patent Document 2).

Japanese Patent No. 3536618 Japanese Patent No. 3358549

  SUMMARY OF THE INVENTION An object of the present invention is to provide a semiconductor wafer evaluation method for easily evaluating the microroughness of a semiconductor wafer surface in a short time in order to effectively perform polishing and cleaning at the time of manufacturing a semiconductor wafer, and a semiconductor using the evaluation method The object is to provide a method for manufacturing a wafer.

  In order to achieve the above object, the present invention is a method for evaluating a semiconductor wafer, and measures at least the haze value of vertical irradiation / high angle light reception and / or the oblique irradiation / low angle light reception of a semiconductor wafer surface in advance. And measuring the surface shape of the wafer, converting the measured surface shape data into a power spectrum, and in the power spectrum, the power spectrum density at a spatial wavelength of 1 μm and the vertical irradiation / high angle light receiving haze. There is provided a semiconductor wafer evaluation method characterized by obtaining a correlation between a value and / or a correlation between a power spectral density at a spatial wavelength of 0.1 μm and the oblique angle irradiation / low angle light receiving haze value. (Claim 1).

  In this way, the haze value of vertical irradiation / high angle light reception and / or the oblique angle irradiation / low angle light reception haze value of the semiconductor wafer surface is measured in advance, and the surface shape of the wafer is measured, and this is converted into a power spectrum. In the power spectrum, the correlation between the power spectral density at a spatial wavelength of 1 μm and the vertical irradiation / high angle light receiving haze value and / or the power spectral density at a spatial wavelength of 0.1 μm and oblique irradiation / low angle light reception If the correlation with the haze value is obtained, the correlation between the power spectral density at a spatial wavelength where the influence of wafer polishing and cleaning conditions is likely to appear and the haze value that can be measured more easily becomes clear. Can be used for quantitative evaluation of the surface shape of the wafer for effective polishing and cleaning.

  Here, the vertical irradiation / high-angle light receiving haze value is measured by irradiating the wafer surface with test light from the vertical direction and receiving light scattered in the direction of an angle of about 80 ° from the wafer surface with a light receiver. Haze value in the case of oblique angle irradiation / low angle light receiving haze value is a test light irradiated from an angle direction of about 45 ° from the wafer surface and scattered in an angle direction of about 45 ° from the wafer surface. It is a haze value when the received light is received by a light receiver and measured.

In this case, the haze value of vertical irradiation / high-angle light reception and / or haze value of oblique-angle irradiation / low-angle light reception on the semiconductor wafer surface is measured, and the power spectrum at the spatial wavelength is measured using the haze value and the correlation. It is preferable to evaluate the surface shape of the semiconductor wafer by calculating the density (claim 2).
As described above, the haze value of vertical irradiation / high angle light reception and / or the oblique angle irradiation / low angle light reception haze value of the semiconductor wafer surface is measured, and the measured haze value and the correlation are used in the spatial wavelength. By calculating the power spectral density, if the surface shape of the semiconductor wafer is evaluated, the surface shape is measured each time the evaluation is performed, and this is converted into a power spectrum. Simple surface shape evaluation can be performed in a short time.

The haze value can be measured with a particle counter.
Thus, by measuring the haze value with a particle counter, the measurement can be easily performed using a conventional measuring apparatus.

In this case, the surface shape of the semiconductor wafer can be measured by any one of an atomic force microscope method, a stylus method, a light interference method, a phase shift interference method, and a light scattering topography method.
Thus, by measuring the surface shape of a semiconductor wafer by any of atomic force microscopy, stylus method, optical interferometry, phase shift interferometry, or light scattering topography, a conventional measuring device can be used. Measurement can be performed easily and quickly.

  Further, the present invention is a method for producing a semiconductor wafer, wherein at least a wafer obtained by slicing a semiconductor ingot is polished and then washed, and the surface shape of the wafer is evaluated by any of the above methods, According to the evaluation result, there is provided a method for producing a semiconductor wafer, characterized in that polishing conditions and / or cleaning conditions are adjusted.

  As described above, if the surface shape of the wafer is evaluated by any of the above methods, and the polishing conditions and / or the cleaning conditions are adjusted according to the evaluation results, the influence of the polishing and cleaning conditions of the wafer is particularly likely to appear. High quality by effectively polishing and / or cleaning by adjusting to optimum polishing conditions and / or cleaning conditions to improve the microroughness of the wafer surface according to the haze value correlated with the spatial wavelength This makes it possible to manufacture a semiconductor wafer.

In this case, it is preferable to adjust the polishing conditions according to the evaluation result of haze of vertical irradiation / high angle light reception and / or adjust the cleaning condition according to the evaluation result of haze of oblique angle irradiation / low angle light reception. (Claim 6).
As described above, if the polishing conditions are adjusted according to the evaluation result of haze of vertical irradiation / high angle light reception and / or the cleaning conditions are adjusted according to the evaluation result of haze of oblique angle irradiation / low angle light reception, the spatial wavelength The power spectral density at 1 μm and / or the spatial wavelength of 0.1 μm can be effectively reduced, and the microroughness of the wafer surface can be effectively improved.

Further, it is preferable to adjust the polishing conditions and the cleaning conditions so that at least the haze value of vertical irradiation / high angle light reception is 10 ppb or less and the haze value of oblique irradiation / low angle light reception is 2 ppb or less. .
Thus, if the polishing conditions and the cleaning conditions are adjusted so that at least the haze value for vertical irradiation / high-angle light reception is 10 ppb or less and the haze value for oblique irradiation / low-angle light reception is 2 ppb or less, the micro- The roughness becomes sufficiently small, and it becomes possible to manufacture a semiconductor wafer having a surface with a small microroughness sufficient to achieve electrical characteristics required by high integration and high precision of recent devices.

  According to the present invention, the haze value of vertical irradiation / high angle light reception and / or the oblique angle irradiation / low angle light reception haze value of the semiconductor wafer surface is measured in advance, and the surface shape of the wafer is measured, and this is converted into a power spectrum. In the power spectrum, the correlation between the power spectral density at a spatial wavelength of 1 μm and the vertical irradiation / high angle light-receiving haze value and / or the power spectral density at a spatial wavelength of 0.1 μm and the oblique irradiation / low If the correlation with the angle light reception haze value is obtained, the correlation between the power spectral density at a spatial wavelength that is particularly susceptible to wafer polishing and cleaning conditions and the haze value that can be measured more easily becomes clear. This can be used for quantitative evaluation of the surface shape of the wafer for effective polishing and cleaning.

  In the manufacture of semiconductor wafers, the inventors have a correlation between the power spectral density at a spatial wavelength of 1 μm and the vertical irradiation / high-angle light-receiving haze value, which are easily affected by polishing conditions, and the influence of cleaning conditions. It has been found that there is a correlation between the power spectral density at an easily appearing spatial wavelength of 0.1 μm and the oblique angle irradiation / low angle light receiving haze value. In order to obtain the power spectrum of the wafer surface in the past, the surface shape of the wafer had to be measured and converted to a power spectrum, but there was a problem that it took time to measure the surface shape. In view of the above, it has been conceived that a haze value that can be more easily measured in advance is also measured, and a correlation between the haze value and the power spectral density at the predetermined spatial wavelength is obtained. Then, instead of measuring the surface shape each time the wafer is evaluated, only the haze value is measured, and the power spectral density at a predetermined spatial wavelength is calculated from the haze value using the correlation. The present invention has been completed by conceiving that the microroughness of the wafer surface can be easily evaluated in a short time.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited thereto.

FIG. 1 is a process diagram showing an example of a semiconductor wafer evaluation method according to the present invention.
First, a semiconductor wafer for obtaining the correlation between the power spectrum of the surface shape and the haze value is prepared (step A).
This semiconductor wafer is obtained by, for example, slicing a semiconductor ingot such as silicon or another compound semiconductor grown by the CZ method or the FZ method, and appropriately performing steps such as chamfering, lapping, etching, polishing, and cleaning by a conventional method. However, there is no particular limitation.

  In the conventional polishing process, primary polishing (rough polishing) performed to increase the flatness of the wafer surface after the etching process, etc., and a mirror surface is obtained by reducing haze, and scratches generated by the rough polishing are removed. And finish polishing for the purpose. In rough polishing, a relatively hard material with an Asker C strength of about 80 in which polyurethane is impregnated with polyester felt (a random structure) is used as an abrasive cloth, and colloidal silica is used as an abrasive in an alkali-based aqueous solution. What was contained can be used. On the other hand, in the finish polishing, a polishing cloth made of a suede-like artificial leather made of soft foamed urethane can be used, and an alkali-based aqueous solution containing colloidal silica can be used as an abrasive.

  Further, in the cleaning process, a conventional cleaning process such as RCA cleaning, which is a combination of removing foreign substances on the wafer surface with chemicals and rinsing with pure water, can be used. For example, a typical process procedure for RCA cleaning is performed as follows. That is, 1) SC-1 cleaning (ammonia: hydrogen peroxide water: water = 1: 1: 5-7), 2) pure water rinse, 3) hydrofluoric acid cleaning, 4) pure water rinse, 5) SC- 2 cleaning (hydrochloric acid: hydrogen peroxide water: water = 1: 1 to 2: 6 to 8), 6) pure water rinse, and 7) spin dry. The pure water rinsing process may be repeated multiple times.

Next, the haze value of vertical irradiation / high-angle light reception and / or haze value of oblique-angle irradiation / low-angle light reception on the surface of the semiconductor wafer thus prepared is measured (step B).
The measuring method and measuring device at this time are not particularly limited as long as they can measure the haze value of vertical irradiation / high angle light reception and / or the haze value of oblique irradiation / low angle light reception. Can be used to easily measure the haze value with a conventional measuring apparatus. Examples of such a particle counter include SP-1 manufactured by KLA-Tencor, and the haze value of vertical irradiation and high-angle light reception can be measured in a DNN (Dark-field Narrow Normal) mode provided in this apparatus. Haze values for oblique angle irradiation and low angle light reception can be measured in a DWO (Dark-Field Wide Oblique) mode provided in this apparatus.
Hereinafter, the haze value for vertical irradiation / high angle light reception may be referred to as DNN value, and the haze value for oblique irradiation / low angle light reception may be described as DWO value.

Next, the surface shape of the prepared semiconductor wafer is measured (step C).
The method for measuring the surface shape is not particularly limited, and can be measured by any of atomic force microscopy, stylus method, light interferometry, phase shift interferometry, and light scattering topography. For measurement by atomic force microscopy, for example, an atomic force microscope (AFM) manufactured by Hitachi Construction Machinery Finetech Co., Ltd. can be used. In addition, other methods may be used as long as the surface shape can be measured, and the measurement can be easily performed using a conventional measuring apparatus. The measurement area can be, for example, 1 μm × 1 μm, but is not particularly limited.

Next, the surface shape measured in this way is converted into a power spectrum (step D).
In this case, for example, the measured surface shape data is processed using Fourier transform by software “SPIP” manufactured by Image Metrology Co., and 2πd / N (N is the number of data, d is the number of data) By multiplying the sampling interval, it can be converted into a power spectrum. The number of data can be, for example, 100 to 1000, and the sampling interval can be, for example, 0.01 μm, but is not particularly limited.

  In addition, you may perform any of the process of measuring the haze value of the process B, and the process of measuring the surface shape of processes C-D and converting this into a power spectrum. For the next step, a plurality of haze values and power spectrum data measured by changing polishing conditions and cleaning conditions are prepared. At this time, only one wafer or a plurality of wafers may be used in order to perform measurement while changing the polishing conditions and the cleaning conditions.

Next, in the power spectrum thus converted, the correlation between the power spectral density at a spatial wavelength of 1 μm and the vertical irradiation / high-angle received haze value (DNN value) and / or the power spectral density at a spatial wavelength of 0.1 μm. And the oblique angle irradiation / low angle light receiving haze value (DWO value) is obtained (step E).
For example, the correlation function is obtained by approximating a data set of power spectral density and DNN value at a spatial wavelength of 1 μm obtained by changing polishing conditions and cleaning conditions by a linear function using the least square method. Ask. The correlation function between the power spectral density at a spatial wavelength of 0.1 μm and the DWO value is obtained in the same manner. As the present inventors have found, since these values have a correlation, a highly accurate correlation function can be obtained.

Then, a semiconductor wafer for evaluating the surface shape was prepared in the same manner as in Step A (Step F), the DNN value and / or DWO value of the wafer surface was measured, and these haze values were obtained in Step E. The surface shape of the semiconductor wafer is evaluated by calculating the power spectral density at a spatial wavelength of 1 μm and / or 0.1 μm using the correlation (Step G).
Since the vicinity of these spatial wavelengths in the power spectrum is a wavelength that is particularly susceptible to polishing and cleaning conditions in the wafer manufacturing process, if the power spectral density at these spatial wavelengths is determined from the correlation with the haze value, Therefore, it is possible to quantitatively evaluate the microroughness of the surface of the semiconductor wafer for effective polishing and cleaning.

  In other words, conventional parameters such as average roughness (Ra) representing microroughness only include information on the height of microroughness, so even if the wafer has a different surface state, it appears in the parameter. It was difficult. On the other hand, for example, in the conventional method of measuring the haze value with a particle counter or the like, even when the same wafer is measured, the difference in the measured value may be large for each measuring instrument, and only a relative evaluation can be performed, making it difficult to quantify. It was. However, with the evaluation method according to the present invention, the haze value is used for evaluation based on the correlation with the quantifiable power spectral density, so that the problem that the above quantification is difficult can be solved. Once the correlation is obtained in this way, it is not necessary to obtain the power spectrum by measuring the surface shape for each evaluation, and the power spectrum density at a predetermined spatial wavelength can be obtained only by measuring the haze value. Therefore, the wafer can be easily evaluated in a short time.

  Next, a method for manufacturing a semiconductor wafer according to the present invention will be described. A method for producing a semiconductor wafer according to the present invention is a method for producing a semiconductor wafer, wherein at least a wafer obtained by slicing a semiconductor ingot is polished and then cleaned, and the surface shape of the wafer is formed by any of the above methods. Evaluation is performed, and polishing conditions and / or cleaning conditions are adjusted according to the evaluation results.

  That is, if the surface shape of the wafer surface is evaluated by any one of the methods described above, it is quantitatively determined based on the DNN value and DWO value that have a correlation with the power spectral density at a predetermined spatial wavelength that is particularly susceptible to polishing and cleaning conditions. Therefore, if the polishing conditions and / or the cleaning conditions are adjusted according to the evaluation results, the semiconductor wafer can be used under the optimum polishing conditions and / or cleaning conditions in order to improve the microroughness of the wafer surface. Can be manufactured.

  In particular, it is preferable to adjust the polishing conditions according to the evaluation result of haze for vertical irradiation and high angle light reception, and to adjust the cleaning condition according to the evaluation result of haze for oblique angle irradiation and low angle light reception. The influence of polishing conditions is particularly likely to appear in the power spectral density at a spatial wavelength of 1 μm, which is correlated with the DNN value, and the influence of cleaning conditions is particularly dependent on the power spectral density at a spatial wavelength of 0.1 μm, which is correlated with the DWO value. It is easy to appear. Therefore, if the polishing and cleaning conditions are adjusted according to the evaluation results of each haze, the power spectral density at each spatial wavelength can be effectively reduced, and the microroughness of the wafer surface can be effectively improved. It becomes.

  Examples of the adjustment of the polishing conditions include adjustment of the surface roughness of the polishing cloth and adjustment of the pH of the abrasive. Examples of the adjustment of the cleaning conditions include a change from RCA cleaning to two-fluid cleaning, a change in the concentration and type of cleaning liquid, and the like.

  In the two-fluid cleaning, two or more kinds of fluids are mixed, and the mixed fluid is jetted onto the wafer surface to remove impurities, and haze can be reduced by the two-fluid cleaning. For example, two-fluid cleaning can be performed by mixing ultrapure water to which carbon dioxide has been added and nitrogen gas and injecting this mixed fluid onto the wafer surface. If the ultrapure water to which carbon dioxide is added is used as a cleaning liquid, static electricity generated by friction between the surface of the semiconductor wafer and the cleaning liquid can be suppressed. Further, as the gas used as the gas, nitrogen gas which is an inert gas is suitable, but air, argon gas or the like can also be used. If a mixed aqueous solution of ammonia water, hydrogen peroxide water and water is used as the cleaning liquid instead of ultrapure water, cleaning with an etching action can be performed.

  Also, if the polishing conditions and the cleaning conditions are adjusted so that at least the haze value for vertical irradiation / high angle light reception is 10 ppb or less and the haze value for oblique irradiation / low angle light reception is 2 ppb or less, high integration of recent devices Thus, a semiconductor wafer having a surface with a small microroughness sufficient to achieve the required electrical characteristics can be achieved. Such a low haze value can be achieved, for example, by performing the above-described two-fluid cleaning, but the method for achieving this is not particularly limited.

Examples of the present invention will be described in more detail below, but the present invention is not limited thereto.
(Experiment 1)
A silicon single crystal ingot grown by the CZ method was sliced and chamfered, lapped, etched, polished, and washed by a conventional method to produce a silicon wafer having a diameter of 300 mm. The polishing conditions at this time are based on conventional rough polishing and finish polishing, and the cleaning conditions are also based on conventional RCA cleaning. Next, the DNN value and DWO value of the silicon wafer surface were measured in the DNN mode and DWO mode of SP-1 manufactured by KLA-Tencor, which is a particle counter. At this time, the DNN value was about 50 ppb, and the DWO value was about 12 ppb. Next, the surface shape was measured with an AFM manufactured by Hitachi Construction Machinery Finetech Co., Ltd. with a measurement area of 1 μm × 1 μm and a height range of 1 nm. Processing was performed using Fourier transform by “SPIP”, and the data output by the processing was converted to a power spectrum by multiplying by 2πd / N (N is the number of data and d is a sampling interval). The number of data was 100, and the sampling interval was 0.01 μm. The power spectrum A thus obtained is shown in FIG. At this time, the power spectral density at a spatial wavelength of 1 μm was about 2.0 × 10 ⁻³ nm ³ , and the power spectral density at a spatial wavelength of 0.1 μm was about 2.0 × 10 ⁻⁴ nm ³ .

(Experiment 2)
Next, a silicon wafer was prepared in the same manner as in Experiment 1 except that the surface roughness of the polishing cloth was reduced in the final polishing and the pH of the abrasive was adjusted, and the haze value was measured with a particle counter. The DNN value was improved to about 15 ppb and the DWO value was improved to about 10 ppb. Next, the surface shape was measured by AFM, and this measurement data was converted into a power spectrum. The power spectrum B thus obtained is shown in FIG. At this time, the power spectral density at a spatial wavelength of 1 μm is greatly improved to about 1.5 × 10 ⁻³ nm ³ , and the power spectral density at a spatial wavelength of 0.1 μm is about 1.5 × 10 ⁻⁴ nm ³ . Improved.

(Experiment 3)
Next, in the same manner as in Experiment 2, the surface roughness of the polishing cloth was reduced in final polishing, and the pH of the abrasive was adjusted to be low, and the experiment was performed except that the cleaning process was changed from RCA cleaning to two-fluid cleaning. A silicon wafer was produced in the same manner as in Example 1. In the two-fluid cleaning at this time, ultrapure water to which carbon dioxide was added and nitrogen gas were mixed, and this mixed fluid was jetted onto the wafer surface. When the haze value of this silicon wafer was measured with a particle counter, the DNN value was improved to about 7 ppb and the DWO value was greatly improved to about 2 ppb. Next, the surface shape was measured by AFM, and this measurement data was converted into a power spectrum. The power spectrum C thus obtained is shown in FIG. At this time, the power spectral density at a spatial wavelength of 1 μm is improved to about 1.3 × 10 ⁻³ nm ³ , and the power spectral density at a spatial wavelength of 0.1 μm is significantly about 4.0 × 10 ⁻⁵ nm ^3. Improved.

(Calculation of correlation coefficient)
Based on the results of Experiment 1 to Experiment 3, a graph plotting the corresponding haze value and power spectral density was created. This graph is shown in FIG. 3A is a graph showing the correlation between the power spectral density at a spatial wavelength of 1 μm and the DNN value, and FIG. 3B is a graph showing the correlation between the power spectral density at a spatial wavelength of 0.1 μm and the DWO value. is there. Thus, the power spectral density and the haze value at each spatial wavelength have a correlation. By approximating this data with a linear function using the least square method, the power spectral density at a spatial wavelength of 1 μm is X ₁ (nm ³ ), and the power spectral density at a spatial wavelength of 0.1 μm is X ₂ (nm ³ ). In this case, correlation functions such as X ₁ = 2 × 10 ⁻⁵ DNN + 1.2 × 10 ⁻³ and X ₂ = 2 × 10 ⁻⁵ DWO + 7 × 10 ⁻⁶ were obtained.

  That is, since the correlation function between the haze value and the power spectral density at a predetermined spatial wavelength is obtained based on the results of Experiments 1 to 3, the correlation function is used when evaluating the silicon wafer thereafter. By using this, the power spectral density at a spatial wavelength of 1 μm and the power spectral density at a spatial wavelength of 0.1 μm can be calculated simply by measuring the haze value.

  Therefore, if the polishing conditions are adjusted according to the evaluation result of the DNN value and the cleaning conditions are adjusted according to the evaluation result of the DWO value, the power spectral density at a spatial wavelength of 1 μm and a spatial wavelength of 0.1 μm is effectively reduced. This can effectively improve the microroughness of the wafer surface. In particular, if the polishing and cleaning conditions are adjusted so that at least the DNN value is 10 ppb or less and the DWO value is 2 ppb or less, the microroughness of the wafer surface becomes sufficiently small, and the recent device integration and high accuracy are achieved. It becomes possible to manufacture a semiconductor wafer having a microroughness surface sufficient to achieve electrical characteristics required by the fabrication.

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

It is process drawing which shows an example of the evaluation method of the semiconductor wafer which concerns on this invention. It is a graph which shows the power spectra A, B, and C of the surface state of the silicon wafer obtained in Experiment 1 to Experiment 3. (A) is a graph showing the correlation between the power spectral density at a spatial wavelength of 1 μm and the DNN value, and (b) is a graph showing the correlation between the power spectral density at a spatial wavelength of 0.1 μm and the DWO value.

Claims (7)

  A method for evaluating a semiconductor wafer, at least measuring a haze value of vertical irradiation / high angle light reception and / or a haze value of oblique angle irradiation / low angle light reception on a semiconductor wafer surface in advance and measuring the surface shape of the wafer Then, the measured wafer surface shape data is converted into a power spectrum, and in the power spectrum, the correlation between the power spectrum density at a spatial wavelength of 1 μm and the vertical irradiation / high angle received haze value and / or the spatial wavelength A method for evaluating a semiconductor wafer, characterized in that a correlation between a power spectral density at 0.1 μm and the oblique angle irradiation / low angle light receiving haze value is obtained.   The evaluation method according to claim 1, wherein a haze value of vertical irradiation / high angle light reception and / or a haze value of oblique irradiation / low angle light reception on a semiconductor wafer surface is measured, and the haze value and the correlation are measured. A method for evaluating a semiconductor wafer, wherein the surface shape of the semiconductor wafer is evaluated by calculating the power spectral density at the spatial wavelength using   The evaluation method according to claim 1, wherein the haze value is measured with a particle counter.   The evaluation method according to any one of claims 1 to 3, wherein the surface shape of the semiconductor wafer is determined by atomic force microscopy, stylus method, optical interferometry, phase shift interferometry, light scattering. An evaluation method characterized by measuring by any of the topography methods.   5. A method for manufacturing a semiconductor wafer, comprising: polishing a wafer obtained by slicing a semiconductor ingot and then cleaning the wafer, wherein the surface shape of the wafer is changed by the method according to claim 1. A method for manufacturing a semiconductor wafer, characterized by evaluating and adjusting polishing conditions and / or cleaning conditions according to the evaluation results.   6. The manufacturing method according to claim 5, wherein the polishing condition is adjusted according to a haze evaluation result of vertical irradiation / high angle light reception and / or a haze evaluation result of oblique angle irradiation / low angle light reception. A manufacturing method characterized by adjusting the cleaning conditions.   The manufacturing method according to claim 5 or 6, wherein at least the haze value of vertical irradiation / high angle light reception is 10 ppb or less and the haze value of oblique irradiation / low angle light reception is 2 ppb or less. A manufacturing method comprising adjusting cleaning conditions.

Images