JP2006038587A - Inspection method of crystal film and inspection device therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inspection method of a crystal film capable of certainly determining the lowering of the characteristics of a crystal film and capable of reducing a treatment tact, and an inspection device therefor. <P>SOLUTION: In a process for calculating the number of stripes, the number of stripes is calculated by measuring only a stripe-like density change without calculating a distribution of a density value in a laser scanning direction and, at the first time when the number of stripes becomes below "1", the distribution of the density value in the laser scanning direction is calculated by a density value calculation process. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a crystal film inspection method and an inspection apparatus, and more particularly to an inspection method and an inspection apparatus for inspecting a polysilicon film generated by performing an excimer laser annealing process when a liquid crystal display panel is manufactured.
In the present invention, the “crystal film” is synonymous with a crystalline silicon semiconductor film.

  In manufacturing a thin film transistor (TFT) used as an active element of a liquid crystal display, it is common to use a thin film silicon semiconductor. Thin film silicon semiconductors are roughly classified into two types: amorphous silicon semiconductors made of amorphous silicon (amorphous silicon) and crystalline silicon semiconductors having crystallinity.

Amorphous silicon semiconductors are most commonly used because they have characteristics such as a relatively low film formation temperature, can be manufactured relatively easily by a vapor deposition method, and are rich in mass productivity. . However, since amorphous silicon semiconductors are inferior in physical properties such as conductivity compared to crystalline silicon semiconductors, establishment of a manufacturing technique for TFTs made of crystalline silicon semiconductors is strongly required to obtain high-speed characteristics. In other words, plasma CVD (CVD:
An amorphous silicon thin film is formed by a chemical vapor deposition (vacuum chemical vapor deposition) method or a low pressure thermal chemical vapor deposition method, and sequentially undergoes a solid phase growth crystallization process (abbreviated as SPC) and a laser annealing crystallization process (abbreviated as ELA). A conductive silicon semiconductor film (hereinafter referred to as a crystal film) is formed.

  Conventionally, a technique for inspecting a crystal film crystallized by an excimer laser annealing apparatus has been disclosed (for example, Patent Document 1). In the prior art described in Patent Document 1, light having a predetermined directionality is irradiated to one surface portion of a substrate, the intensity of irregularly reflected light from one surface portion is measured, and one surface is based on the measured value. A technique for determining the uneven state of a portion is disclosed. The intensity of the irregularly reflected light is measured by Fourier analysis focusing on the occurrence of “streaks” having a specific directionality and periodicity resulting from laser scanning in an excimer laser annealing apparatus. If it is determined from the uneven state of the one surface portion that the crystal film of this substrate is rough, the crystal film is determined to be defective.

  In addition, the applicant of the present invention specifies the microcrystal that is the main cause of the deterioration of the properties such as conductivity from the change of the uneven state without depending on the periodicity of the uneven state of the crystal film, thereby reducing the characteristic of the crystal film. A technique for reliably determining whether or not is present (Patent Document 2). FIG. 6 is a flowchart showing a procedure for measuring the crystallinity of a conventional substrate with a crystal film. Furthermore, the present applicant has put to practical use a technique to which Patent Document 2 is applied as a crystallinity determination method with high versatility. That is, in the first step, in the image obtained by imaging the crystal film from one side in the thickness direction, any one point in the first direction (row) that is the extending direction of the plurality of columns of band-like portions with different laser energy intensities The density values in the intersecting second direction (column) are calculated, and the density value distribution in the second direction is obtained.

  In the second step, the imaging system is switched to a different one from that in the first step. Next, in the third step, a streaky density change region is extracted as the number of fringes for the image captured by the imaging system in which the same part as the first step is switched in the second step, and the distribution of the number of fringes in the second direction is calculated. Ask. Thereafter, in the fourth step, the analysis result of the density value in the second direction and the analysis result of the number of stripes in the second direction are displayed.

  FIG. 7 is a diagram illustrating an example of a substrate with a crystal film in which laser energy intensity is changed stepwise with respect to an irradiation target and laser irradiation is performed in a band shape according to the related art. This will be described with reference to FIG. First, in step b1, a measurement head (not shown) is moved vertically above the first measurement point 1 with respect to one surface portion of the substrate. Next, the process proceeds to step b3, in which the scattered light at the first measurement point is measured by the first imaging system having an optical magnification of about 0.5, and the density value is calculated. Next, in step b4, the optical system is switched to the second imaging system having an optical magnification of about 5. In step b5, the stripe-like density change region at the first measurement point 1 is calculated as the number of stripes by image processing. Next, the process moves to step b7, the measurement head is moved vertically above the second measurement point 2, the scattered light at the second measurement point is measured by the first imaging system, and the second measurement point is measured by the second imaging system. Measure the change in muscle density. Thereafter, the same operation is repeated up to the 200th measurement point. After a series of measurements is completed, the density value distribution result and the stripe number distribution result with respect to the changing direction of the laser energy intensity are displayed.

JP 2001-110861 A Japanese Patent Application No. 2002-370964

  The technique for determining the degree of crystallinity using Fourier transform based on the periodicity of the crystal film as in Patent Document 1 is based on the premise that the unevenness state of the crystal film has at least a certain periodicity. However, some crystallized films that are actually crystallized do not have periodicity in the uneven state. Therefore, the technique for determining the degree of crystallinity using Fourier transform based on the periodicity of the crystal film has low versatility.

  In the technology applying Patent Document 2 shown in FIG. 7, there are as many as 200 measurement points on the substrate with a crystal film to be measured, and measurement is performed using two types of imaging systems having different optical magnifications for each measurement point. ing. For example, if it takes 5 seconds per measurement point including the moving time of the measurement head, it takes time for the entire substrate to be multiplied by the total number of measurement points and the type of the imaging system. Specifically, it takes 5 seconds × 200 points × 2 times (type) = 2000 seconds, and the reduction of processing tact is a big problem.

  An object of the present invention is to provide an inspection method and an inspection apparatus for a crystal film that can reliably determine the deterioration of the characteristics of the crystal film and reduce the processing tact.

The present invention is an image obtained by imaging a crystal film having a laser energy intensity that varies stepwise with laser scanning from one side in the thickness direction, and includes a plurality of rows of band-shaped portions continuous in the laser scanning direction. , A stripe number calculation step of extracting a streaky density change region as the number of stripes and obtaining only the distribution of the number of stripes in the laser scanning direction;
When the number of fringes to be extracted in the fringe number calculating step is less than a predetermined number, the density value in the laser scanning direction is calculated for an image captured by switching to an imaging system different from the fringe number calculating step, A method for inspecting a crystal film, comprising: a density value calculating step for obtaining a density value distribution in a laser scanning direction.

  According to the present invention, in the step of calculating the number of fringes, only the distribution of the number of fringes in the laser scanning direction by extracting the stripe-like density change region as the number of fringes from the image having the plurality of rows of strip-like portions continuous in the laser scanning direction. Ask for. The image is an image of a crystal film having a laser energy intensity that varies stepwise with laser scanning from one side in the thickness direction. When the number of fringes to be extracted in this fringe number calculation step is less than a predetermined number, in the density value calculation step, the density in the laser scanning direction is determined for an image captured by switching to an imaging system different from the fringe number calculation step. Calculate the value. Thereby, the distribution of density values in the laser scanning direction is obtained.

  Further, the present invention is a method of extracting the number of stripes from the measurement point of the belt-shaped portion having the maximum laser energy intensity in the step of calculating the number of stripes, and is another measurement point along the laser scanning direction from the measurement point, wherein the laser energy It is characterized in that the number of fringes is extracted at other measurement points where the intensity gradually decreases.

  According to the present invention, in the step of calculating the number of fringes, the number of fringes is extracted from the measurement point of the belt-shaped portion having the maximum laser energy intensity. Further, in the step of calculating the number of fringes, the number of fringes is extracted at other measurement points along the laser scanning direction from the measurement points, where the laser energy intensity is gradually reduced.

  Further, the present invention is characterized in that at least one of the fringe number calculation step and the density value calculation step is performed until the belt-like portion having the minimum laser energy intensity is reached.

  According to the present invention, after extracting the number of fringes from the measurement point of the belt-like portion with the maximum laser energy intensity, until reaching the belt-like portion with the smallest laser energy intensity, at least one of the fringe number calculating step and the concentration value calculating step Do one.

  According to the present invention, in the density value calculating step, when the calculated density value is less than a predetermined density threshold value, the density value in the laser scanning direction, the position of which is different in the extending direction of the band-shaped part to be measured, is calculated. And obtaining a distribution of density values in the laser scanning direction.

  According to the present invention, in the density value calculation step, when the calculated density value is less than a predetermined density threshold value, the density value in the laser scanning direction with a different position in the extending direction of the band-shaped part to be measured is calculated. To do. Thereby, the distribution of density values in the laser scanning direction is obtained.

Further, the present invention is an image obtained by imaging a crystal film whose laser energy intensity varies stepwise with laser scanning from one side in the thickness direction, and has a plurality of rows of strip-shaped portions continuous in the laser scanning direction. Among them, the stripe number calculation means for extracting the stripe-like density change region as the number of stripes and obtaining only the distribution of the number of stripes in the laser scanning direction;
When the number of fringes to be extracted by the fringe number calculating means is less than a predetermined number, the density value in the laser scanning direction is calculated for an image captured by switching to an imaging system different from the fringe number calculating means, A crystal film inspection apparatus comprising density value calculation means for obtaining a distribution of density values in a laser scanning direction.

  According to the present invention, the fringe number calculation means extracts a streaky density change region as the number of fringes from an image having a plurality of rows of strips continuous in the laser scanning direction, and only the distribution of the number of fringes in the laser scanning direction. Ask for. The image is an image of a crystal film having a laser energy intensity that varies stepwise with laser scanning from one side in the thickness direction. When the number of fringes to be extracted by the fringe number calculating means is less than a predetermined number, the density value calculating means switches the density in the laser scanning direction for an image picked up by switching to an imaging system different from the fringe number calculating means. Calculate the value. Thereby, the distribution of density values in the laser scanning direction is obtained.

  According to the present invention, the density value distribution in the laser scanning direction is obtained particularly when the number of stripes is less than a predetermined number. In other words, in the step of calculating the number of fringes, when only the stripe-like density change is measured without calculating the density value distribution in the laser scanning direction, the number of fringes is calculated, and the number of fringes becomes less than the predetermined number For the first time, the density value distribution in the laser scanning direction is obtained in the density value calculation step. Therefore, according to the method for inspecting a crystal film of the present invention, all measurement points in the conventional technique are measured for streaky scattered light by the first imaging system, and a streak density change is measured by the second imaging system. The processing tact can be reduced as compared with the method of doing this. In addition, it is possible to immediately detect an output abnormality of the laser energy intensity from the relationship between the density value in the laser scanning direction and the laser energy intensity and the relationship between the number of stripes and the laser energy intensity. Therefore, it is possible to eliminate a crystal film having an undesired crystallinity, that is, a defective substrate. In this way, it is possible to reliably determine the deterioration of the characteristics of the crystal film and to reduce the processing tact.

  According to the present invention, the number of fringes is extracted from the measurement point of the band-like portion having the maximum laser energy intensity in the fringe number calculating step. Further, in the step of calculating the number of fringes, the number of fringes is extracted at other measurement points along the laser scanning direction from the measurement points, where the laser energy intensity is gradually reduced. Thus, the number of fringes can be extracted at a plurality of measurement points along the laser scanning direction. Therefore, the relationship between the number of stripes and the laser energy intensity can be obtained.

  Further, according to the present invention, after extracting the number of stripes from the measurement point of the belt-like portion having the maximum laser energy intensity, until at least one of the stripe number calculating step and the density value calculating step until reaching the belt-like portion having the minimum laser energy intensity. Do one. As described above, according to the present invention, all measurement points in the prior art are compared with the method of measuring the streaky scattered light with the first imaging system and measuring the streaky density change with the second imaging system. Thus, a reduction in processing tact can be realized.

  Further, according to the present invention, in the density value calculation step, when the calculated density value is less than a predetermined density threshold value, the density value in the laser scanning direction with a different position in the extending direction of the band-shaped part to be measured is obtained. calculate. Thereby, the distribution of density values in the laser scanning direction is obtained. When the density value calculated in this way is less than a predetermined density threshold value, no further measurement is performed in the laser scanning direction at the same extending direction position. In other words, the number of measurement points can be reduced.

  According to the present invention, when the number of stripes is less than a predetermined number, the distribution of density values in the laser scanning direction is obtained. In other words, the fringe number calculation means calculates only the stripe density change without calculating the density value distribution in the laser scanning direction, calculates the fringe number, and only when the island number is less than the predetermined number. The density value calculating means obtains the density value distribution in the laser scanning direction. Therefore, according to the crystal film inspection apparatus of the present invention, all the measurement points in the conventional technique are measured for the streaky scattered light by the first imaging system, and the streaky density change is measured by the second imaging system. The processing tact can be reduced as compared with the technology to do. In addition, it is possible to immediately detect an output abnormality of the laser energy intensity from the relationship between the density value in the laser scanning direction and the laser energy intensity and the relationship between the number of stripes and the laser energy intensity. Therefore, it is possible to eliminate a crystal film having an undesired crystallinity, that is, a defective substrate. In this way, it is possible to reliably determine the deterioration of the characteristics of the crystal film and to reduce the processing tact.

  FIG. 1 is a flowchart showing a procedure for measuring the degree of crystallinity of a substrate with a crystal film according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of a substrate with a crystal film that is irradiated with laser in a band shape while changing the laser energy intensity stepwise with respect to the irradiation target. This embodiment shows an example in which the inspection apparatus of the present invention is applied to an inspection apparatus for inspecting a crystalline silicon semiconductor film (hereinafter referred to as “crystal film”) used when manufacturing a TFT, for example. The following description includes a description of a crystal film inspection method.

  In the present embodiment, as shown in FIG. 1, in step a1, a process for measuring the degree of crystallinity of the substrate with crystal film 10 is started under the condition that, for example, a power supply (not shown) is turned on. However, it is not limited only to this starting condition. The control subject of this process is the control device 11 described later (see FIG. 5). The control device 11 stores a program for measuring the crystallinity of the substrate 10. In step a2, first, the measurement head is moved in the thickness direction of the first measurement point with respect to one surface portion of the substrate 10. The “substrate” is synonymous with a substrate with a crystal film. The first measurement point is a region within the belt-shaped irradiation region Sa having the maximum laser energy intensity. The inside of the belt-shaped irradiation area Sa corresponds to a belt-shaped portion. Next, the process proceeds to step a3, and a streak-like density change region at the first measurement point is calculated as a total number by image processing by an imaging system having an optical magnification of about 5.

  Next, the process proceeds to step a4, and when it is determined that the calculated number of stripes is not less than “1”, in other words, the calculated number of stripes is “1” or more, the process proceeds to step a5. The number of stripes “1”, which is a criterion, corresponds to a predetermined number. In step a5, the measuring head is moved. That is, in the belt-shaped irradiation region Sa adjacent to the belt-shaped irradiation region Sa in the laser scanning direction (indicated by the arrow D1), the laser energy intensity is one step lower (for example, 5 mJ). The measurement head is moved in one thickness direction of the measurement point. Thereafter, the process returns to step a3. In step a3, the stripe-shaped density change region at the second measurement point is calculated as the number of stripes by image processing. Thus, only the stripe density change measurement is repeated until the calculated number of stripes is less than 1 (zero).

  In step a4, for example, when it is determined that the number of fringes calculated at the sixth measurement point is less than “1”, in step a6, the imaging system is switched to an optical magnification of about 0.5. Next, the process proceeds to step a7, the scattered light at the sixth measurement point is measured, and the concentration value is calculated. Next, the process proceeds to step a8, and it is determined whether or not the calculated density value is larger than a predetermined density threshold value. If it is determined that the calculated density value is larger than the density threshold value, the process proceeds to step a10. In step a10, it is determined whether or not a preset measurement point has been measured. If it is determined that the measurement point set here is not measured, the process returns to step a5 to move the measurement head in the laser scanning direction, and in step a3, the streaky density change region of the new measurement point is obtained by image processing. Calculate as the number of stripes.

  If it is determined in step a10 that a preset measurement point has been measured, the process proceeds to step a11 to display the measurement result, and then the process ends in step a12. If it is determined in step a8 that the calculated density value is not greater than the density threshold value, in other words, the calculated density value is less than the density threshold value, the measurement in that column is terminated and laser scanning is performed. The measurement head is moved to the twentieth row of the next column parallel to the direction. Thereafter, the process returns to step a3.

  FIG. 3 is a diagram showing the relationship between the density value and the number of stripes with respect to the laser energy intensity. From the measurement results described above, the measured density distribution (a) in the density region above the density threshold with respect to the laser energy intensity, and the stripe number distribution in the intensity area above the laser energy intensity corresponding to the density threshold ( B) can be obtained and displayed as necessary. The measured concentration distribution and the number distribution of the stripes with respect to the laser energy intensity obtained by the inspection method according to the present embodiment are not displayed for the entire region of the laser energy intensity, but the laser energy that generates microcrystals depending on the presence or absence of the stripes. Strength is revealed. At the same time, since the concentration value corresponding to the crystallinity in the laser energy intensity region where no microcrystals are generated is found, necessary and sufficient information can be obtained.

  Regarding the number of measurement points in this embodiment, for example, the measurement points with the number of stripes “1” or more in the first column are from the 20th row to the 16th row, and the density value in the first column is less than the threshold value. The measurement points are measurement points on the fifth row and below. At this time, the number of measurement points in the first column is “10”, which is a value obtained by adding “5” rows from the fifth row to the “5” rows from the 20th row to the 16th row. Multiply 2 ”times (number of times of measurement in different imaging systems) and add“ 5 ”points to 25 points. Thereafter, similarly, the measurement points having the number of stripes of “1” or more in the second column are from the 20th row to the 16th row, and the measurement points having a density value less than the threshold value in the second column are the fifth. Measurement points below the line. At this time, the number of measurement points in the second row is 25 points obtained by multiplying “10” points by “2” times and adding “5” points.

  The measurement points with the number of stripes of “1” or more in the third column are from the 20th row to the 15th row, and the measurement points whose density value is less than the threshold value in the third column are the 4th row or less. It is a measuring point. At this time, the number of measurement points in the third row is 26 points obtained by multiplying “10” points by “2” times and adding “6” points. The measurement points with the number of stripes “1” or more in the fourth column are from the 20th row to the 17th row, and the measurement points having a density value less than the threshold value in the fourth column are those in the sixth row or less. It is a measuring point. At this time, the number of measurement points in the fourth column is 24 points obtained by multiplying “10” points by “2” times and adding “4” points. The measurement points with the number of stripes “1” or more in the fifth column are from the 20th row to the 16th row, and the measurement points whose density value is less than the threshold value in the fifth column are those in the fifth row or less. It is a measuring point. At this time, the number of measurement points in the fifth column is 25 points obtained by multiplying “10” points by “2” times and adding “5” points.

  Therefore, in this embodiment, the total number of measurement points is 125 points. Since the conventional number of measurement points is 200 (20 rows × 5 columns × 2 times), in this embodiment, the number of measurement points can be reduced by about 38% compared to the conventional technique. As described above, according to the inspection method according to the present embodiment, in the conventional technique, all of the measurement points are measured for the streaky scattered light by the first imaging system, and the streaky density change is measured by the second imaging system. The processing tact can be reduced as compared with the measuring method.

  FIG. 4 is a diagram showing the relationship between the crystallinity and the surface roughness with respect to the laser energy intensity. The crystallinity with respect to the laser energy intensity and the surface roughness of the crystal film will be described. When the intensity of laser energy applied to an amorphous silicon layer is lower than a desired value, the crystallinity of the crystal film tends to be lower than the desired 100% and the surface roughness of the crystal film tends to be low. . When the laser energy intensity for laser annealing is appropriate, non-melted portions are scattered inside melted by the laser energy. Since the crystal grows with the non-melted portion as a crystal nucleus, the crystal has a large crystal grain size of several μm.

  When the intensity of laser energy applied to the amorphous silicon layer is higher than a desired value, microcrystals are generated in the crystal film, and the surface roughness of the microcrystallized portion becomes extremely low. The microcrystallized part is also called a microcrystalline part. When the laser energy intensity of laser annealing becomes excessive, the crystal film is completely melted by the laser energy, and crystal nuclei are formed during cooling. Since it is formed at a high density and randomly, and the crystal grows from each crystal nucleus, it is an aggregate of extremely small crystals having a crystal grain size of several hundred nm.

  The concentration value (crystallinity) and the number of stripes with respect to the laser energy intensity will be described with reference to FIG. Between the laser energy intensity and the crystallinity of the excimer laser annealing apparatus, if the laser energy intensity increases in a region smaller than the laser energy intensity at which the desired crystallinity is obtained, the crystallinity of the crystal film and The concentration value tends to be high. In a region exceeding the laser energy intensity at which a desired crystallinity is obtained, the crystallinity and concentration value of the crystal film tend to decrease as the laser energy intensity increases.

  The laser energy intensity between the laser energy intensity of the excimer laser annealing apparatus and the number of stripes extracted by image processing from the streak density change is smaller than the laser energy intensity at which the desired crystallinity is obtained. Regardless of the size, the number of stripes is “0”. In a region exceeding the laser energy intensity at which a desired crystallinity can be obtained, the number of stripes tends to increase as the laser energy intensity increases.

  Therefore, immediately after the crystallization process by the excimer laser annealing device, the inspection of the crystal film of all the substrates to be produced, that is, the total inspection, or the sampling inspection of the crystal film in all production lot units, the concentration value and the number of stripes The laser energy intensity can be detected by constantly monitoring the fluctuations in the display, for example, on a display. In other words, when the density value falls below a certain level and the stripes become “0”, it is immediately detected that the laser energy intensity is smaller than the laser energy intensity that provides the desired crystallinity. obtain. If the density value is below a certain level or the number of fringes is not “0”, it can be immediately detected that the laser energy intensity is greater than the laser energy intensity at which the desired crystallinity is obtained. In this way, from the relationship between the density value of the captured image and the laser energy intensity, and the relationship between the number of fringes and the laser energy intensity, an output abnormality of the laser energy intensity can be immediately detected, It becomes possible to eliminate a crystal film having an undesired crystallinity, that is, a defective substrate.

  FIG. 5 is a diagram schematically showing the configuration of the crystal film inspection apparatus 12 according to the embodiment of the present invention. The inspection apparatus 12 for inspecting the crystal film includes, for example, an xy stage 13, a measurement head 14 including an imaging unit, an irradiation unit (not shown), a control unit 11 as a fringe number calculation unit and a density value calculation unit, and a display device. And the display 15. The xy stage 13 is configured to be capable of sucking and supporting the substrate 10. A measurement head 14 is provided on one of the xy stages 13, that is, on one side in the thickness direction of the substrate 10. The measurement head 14 is configured to be movable relative to the xy stage 13 in the x and y directions. The x direction is a direction along the longitudinal direction of the rectangular xy stage 13, and the y direction is a direction orthogonal to the x direction and the thickness direction of the substrate 10. The measurement head 14 is provided so that the crystal film 10A formed on the substrate 10 can be imaged. Using this measuring head 14 and the irradiation means, the crystal film 10A can be imaged from one side in the thickness direction.

  According to the inspection method and inspection apparatus 12 for the crystal film 10A described above, the density value distribution in the laser scanning direction is obtained particularly when the number of stripes is less than “1”. In other words, in the step of calculating the number of fringes, when the number of fringes is less than “1” by calculating only the stripe-like density change without calculating the density value distribution in the laser scanning direction and calculating the number of fringes. For the first time, the density value distribution in the laser scanning direction is obtained in the density value calculation step. Therefore, according to the present inspection method and the inspection apparatus 12, all the measurement points in the conventional technique are measured for the streaky scattered light by the first imaging system, and the streaky density change is measured by the second imaging system. Compared with technology, the processing tact can be reduced. In addition, it is possible to immediately detect an output abnormality of the laser energy intensity from the relationship between the density value in the laser scanning direction and the laser energy intensity and the relationship between the number of stripes and the laser energy intensity.

  In the step of calculating the number of fringes, the number of fringes is extracted from the measurement point of the belt-shaped portion where the laser energy intensity is maximum, and the laser energy intensity is stepwise from other measurement points along the laser scanning direction from the measurement point. The number of stripes is extracted at other measurement points that become lower. Thus, the number of fringes can be extracted at a plurality of measurement points along the laser scanning direction. Therefore, the relationship between the number of stripes and the laser energy intensity can be obtained. In addition, after extracting the number of stripes from the measurement point of the belt-like portion having the maximum laser energy intensity, at least one of the stripe number calculating step and the density value calculating step is performed until reaching the belt-like portion having the minimum laser energy intensity. As described above, according to the present embodiment, it is possible to realize a reduction in processing tact as compared with the prior art.

  Further, in the density value calculating step, when the calculated density value is less than a predetermined density threshold value, the density value in the laser scanning direction, the position of which is different in the extending direction of the band-like part to be measured, is calculated. Thereby, the distribution of density values in the laser scanning direction is obtained. When the density value calculated in this way is less than a predetermined density threshold value, no further measurement is performed in the laser scanning direction at the same extending direction position. In other words, the number of measurement points can be reduced.

  In the present embodiment, the predetermined number of stripes is set to “1”, but the predetermined number of stripes is not necessarily limited to “1”. As another embodiment of the present invention, the number of stripes can be imaged and calculated using an imaging system other than optical magnification × 5. The imaging system in step a6 can be an imaging system other than optical magnification × 0.5. In this embodiment, when the measurement in one column is completed, the measurement head is moved to the next adjacent column. However, the column to which the measurement head is to be moved is not limited to the adjacent column.

It is a flowchart which shows the procedure which measures the crystallinity degree of the board | substrate with a crystal film which concerns on embodiment of this invention. It is a figure which shows an example of the board | substrate with a crystal film which changed the laser energy intensity | strength with respect to the irradiation object in steps, and irradiated the laser in the strip | belt shape. It is a figure which shows the relationship between the density value with respect to a laser energy intensity | strength, and the number of fringes. It is a figure which shows the relationship of the crystallinity degree and surface roughness with respect to a laser energy intensity | strength. 1 is a diagram schematically showing the configuration of a crystal film inspection apparatus 12 according to an embodiment of the present invention. It is a flowchart which shows the procedure which measures the crystallinity degree of the board | substrate with a conventional crystal film. It is a figure which shows an example of the board | substrate with a crystal film which concerns on the prior art and changed the laser energy intensity | strength with respect to the irradiation object in steps, and laser-irradiated in strip shape.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Substrate 10A Crystal film 11 Control apparatus 12 Inspection apparatus

Claims (5)

An image obtained by imaging a crystal film whose laser energy intensity varies stepwise with laser scanning from one side in the thickness direction, and having a plurality of rows of strip-shaped portions continuous in the laser scanning direction. A fringe number calculating step for extracting only the distribution of the number of fringes in the laser scanning direction by extracting the density change region as the number of fringes;
When the number of fringes to be extracted in the fringe number calculating step is less than a predetermined number, the density value in the laser scanning direction is calculated for an image captured by switching to an imaging system different from the fringe number calculating step, And a density value calculating step for obtaining a density value distribution in the laser scanning direction.   In the step of calculating the number of fringes, the number of fringes is extracted from the measurement point of the belt-shaped portion where the laser energy intensity is maximum, and the other measurement points along the laser scanning direction from the measurement point. The method for inspecting a crystal film according to claim 1, wherein the number of fringes is extracted at another measurement point that becomes lower.   3. The crystal film inspection method according to claim 1, wherein at least one of a fringe number calculation step and a concentration value calculation step is performed until the laser energy intensity reaches a strip-shaped portion.   In the density value calculating step, when the calculated density value is less than a predetermined density threshold value, the density value in the laser scanning direction, the position of which is different in the extending direction of the band-shaped part to be measured, is calculated, and the laser scanning direction 3. The method for inspecting a crystal film according to claim 1, wherein a distribution of concentration values of the crystal is obtained. An image obtained by imaging a crystal film whose laser energy intensity varies stepwise with laser scanning from one side in the thickness direction, and having a plurality of rows of strip-shaped portions continuous in the laser scanning direction. A fringe number calculating means for extracting the density change region as the number of fringes and obtaining only the distribution of the number of fringes in the laser scanning direction;
When the number of fringes to be extracted by the fringe number calculating means is less than a predetermined number, the density value in the laser scanning direction is calculated for an image captured by switching to an imaging system different from the fringe number calculating means, An apparatus for inspecting a crystal film, comprising density value calculation means for obtaining a distribution of density values in a laser scanning direction.

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