WO2011071090A1

WO2011071090A1 - Method for analyzing bias of crystal orientation distribution

Info

Publication number: WO2011071090A1
Application number: PCT/JP2010/072054
Authority: WO
Inventors: 久之橋本; 鈴弥山田; 道治中嶋
Original assignee: 電気化学工業株式会社
Priority date: 2009-12-10
Filing date: 2010-12-08
Publication date: 2011-06-16
Also published as: TW201131162A; JP2011122947A

Abstract

Provided is a method for analyzing a bias of a crystal orientation distribution, by which a bias of a crystal orientation distribution of crystal particles in a composite member. The method for analyzing the bias of the crystal orientation distribution has an image creation step (ST1) of creating the image of the cross section of the crystal particles in the composite member, a determination step (ST2) of determining crystal orientations of the respective crystal particles in the image created in the image creation step (ST1), an assaying step (ST3) of specifying the distribution of the crystal orientation determined in the determination step (ST2), and an analysis step (ST4) of analyzing the bias of the crystal orientation distribution by analyzing the distribution obtained in the assaying step (ST3). The determination step (ST2) and the analysis step (ST4) can be carried out by using the electron backscatter diffraction pattern method.

Description

Analysis method of crystal orientation distribution bias

The present invention relates to a method for analyzing the deviation of the crystal orientation distribution. More specifically, the present invention relates to a method for analyzing a deviation in crystal orientation distribution of crystalline particles blended in a composite member.

In various industrial fields such as the semiconductor field, composite members in which crystalline particles are blended with resin or the like are widely used. For example, a technique for sealing a semiconductor chip with a composite member in order to protect the semiconductor device from moisture in the environment is widely known. An example of such a semiconductor device is a white light emitting diode. White light emitting diodes are also called white LEDs. The white light emitting diode is composed of a blue light emitting diode chip and a phosphor. Specifically, a blue light emitting diode chip is coated with a composite member in which a phosphor that is a crystalline particle is blended with a resin or the like. An example of a phosphor is a material that generates yellow fluorescence when blue light is irradiated from a blue light emitting diode. The composite member is also called a wavelength conversion member because it converts blue light into yellow. White light is obtained by mixing the blue light generated from the blue light emitting diode with the yellow light that is excited and emitted by the blue light emission.

The conventional light emitting diode is further described as an example.
FIG. 5 is a cross-sectional view showing the structure of a known light emitting diode. As shown in the figure, the light emitting diode 60 includes a light emitting diode chip 66, a first lead frame 62 on which the light emitting diode chip is mounted, a second lead frame 68, a light emitting diode chip 66, and a first lead. It is composed of a translucent resin material 78 that covers the frame 62 and the second lead frame 68. A recess for mounting the light emitting diode chip 66 is formed in the upper part 62 a of the first lead frame 62. The concave portion has a substantially funnel shape in which the hole diameter gradually increases upward from the bottom surface, and the inner surface of the concave portion is a reflecting surface 64. One electrode on the lower surface side of the light emitting diode chip 66 is die-bonded to the bottom surface of the reflecting surface 64. The other electrode formed on the upper surface of the light-emitting diode chip 66 is connected to the surface 68 a of the second lead frame via the bonding wire 70.

The upper surface and the side surface of the light emitting diode chip 66 are covered with a wavelength conversion member filled in the reflection surface 64. The wavelength conversion member is composed of a resin 72 such as a translucent epoxy and a phosphor 74. In the resin 72, a large number of phosphors 74 that convert light emitted from the light-emitting diode chip 66 into yellow visible light are mixed in a dispersed state. ing. _{Examples of} such phosphors 74 include YAG phosphors whose base material is made of yttrium aluminate (Y ₃ A ₁₅ O ₁₂ ) and whose emission center is cerium (Ce). When a voltage is applied between the first lead frame 62 and the second lead frame 68, the light emitting diode chip 66 emits light. As described above, yellow visible light is emitted from the YAG phosphor 74 by the blue light emission of the light emitting diode chip 66 and the blue light emission. The blue visible light and yellow visible light emitted from the YAG phosphor 74 are mixed to obtain white light. The white light is collected by the convex lens portion 76 of the translucent resin material 78 and emitted to the outside.

As a white light emitting diode that emits mixed color light such as white light other than a single color light emitting diode, a light emitting diode 60 having a wavelength conversion member for converting the wavelength of light emitted from the light emitting diode chip 66 is widely used. . The phosphor 74 used for the wavelength conversion member is composed of a base material such as silicate, phosphate, aluminate, or sulfide and a light emission center contained in these base materials. As the resin 72, in addition to the epoxy resin described in FIG. 5 (see Patent Document 1), an acrylic resin, a silicone resin, or the like is used.

Patent Documents 2 to 4 disclose various configurations when a phosphor is sealed in a resin as a wavelength conversion member in order to reduce color unevenness from a light emitting diode. Patent Document 2 discloses a structure in which a phosphor is uniformly dispersed in a wavelength conversion member. Patent Document 3 discloses a structure in which a phosphor is precipitated in a wavelength conversion member. Patent Document 4 discloses a structure in which phosphors are separated into layers according to emission colors.

When sealing crystalline particles in a resin, a technique for uniformly dispersing or precipitating crystalline particles is common. White light is obtained by mixing the near-ultraviolet to blue light emitted from the light emitting diode and the light converted in wavelength by the phosphor. To obtain white light with high brightness and reduced color unevenness, the phosphor It is necessary to uniformly disperse or settle the phosphor in the wavelength conversion member composed of the sealing resin.

However, when the phosphor particle shape has a high aspect ratio such as columnar or needle-like, the phosphor particles in the sealing resin are like columnar or needle-like particles collapsed, that is, the short axis is against gravity. The crystal orientation distribution in which the directions are biased so as to be parallel is shown.

Therefore, when the crystal orientation is taken into consideration, the phosphor in the wavelength conversion member is unevenly sealed. In this case, the optical path length of the light passing through the phosphor crystal varies. For this reason, control of the crystal orientation distribution of the phosphor particles in the wavelength conversion member is indispensable in order to provide a light-emitting diode having no color unevenness and high brightness. That is, in order to produce a high-performance light emitting diode, it is necessary to control the dispersion state of the phosphor particles in the wavelength conversion member.

JP 2004-152993 A JP 2004-153109 A Japanese Patent No. 3617587 JP 2008-288409 A Japanese Patent No. 3837588

However, it is possible to analyze the crystal orientation of crystalline particles such as phosphor particles dispersed in a composite member such as a wavelength conversion member, and to calculate the bias of the crystal orientation distribution, that is, the crystal in the composite member There has been no measurement and analysis method for evaluating the deviation of the crystal orientation distribution of crystalline particles.

In view of the above problems, an object of the present invention is to provide a crystal orientation distribution bias analysis method for analyzing the crystal orientation distribution bias of crystalline particles in a composite member.

In order to analyze the deviation of the crystal orientation distribution of the crystalline particles in the composite member, the inventors specify the crystal orientation of the crystalline particles by the electron backscatter diffraction image method (Non-Patent Document 1), and further By analyzing the results, the inventors have obtained the knowledge that it is possible to analyze the deviation of the crystal orientation distribution, and have reached the present invention.

In order to achieve the above object, the method for analyzing the deviation of the crystal orientation distribution of the present invention includes an imaging step for imaging a cross section of crystalline particles in a composite member, and the above-described image among the images created by the imaging step. A determination step for determining individual crystal orientations of crystal grains, an analysis step for specifying the distribution of crystal orientations determined in the determination step, and analyzing the distribution obtained in the analysis step to analyze the bias of the crystal orientation distribution An analysis step.

In the above configuration, the determination step and the analysis step are preferably performed using an electron backscatter diffraction image method.
In the electron backscatter diffraction image method, in the determination step, the crystal orientation of the crystalline particles appearing in the cross section of the sealing resin is specified, and in the analysis step, the cross sectional area of the crystalline particles in which the crystal orientation serving as an index of bias is recognized. May be obtained by dividing the cross-sectional area of all the crystalline particles and further multiplying by 100 to obtain the orientation index as a deviation of the crystal orientation distribution.
The crystalline particles may have a columnar crystal surface composed of a bottom surface and a column surface, and the crystal orientation that serves as an index of deviation may be the normal direction of the crystal surface corresponding to the bottom surface or the column surface.
The crystalline particles have a hexagonal crystal shape, and the crystal orientation that serves as an index of deviation may be within a predetermined angle range with respect to the normal direction of the crystal plane corresponding to the bottom surface or the column surface.

According to the present invention, it is possible to analyze the deviation of the crystal orientation distribution of the crystalline particles in the composite member that could not be achieved conventionally, and therefore, it comprises crystalline particles and resins in various industrial fields such as the semiconductor field. The present invention can be effectively applied to a composite member.

By applying the present invention to the crystal orientation distribution analysis of the phosphor in the wavelength conversion member in the light emitting diode, the deviation of the crystal orientation distribution of the phosphor in the wavelength conversion member can be measured. Thereby, it becomes possible to grasp the relationship between the luminous intensity of the light emitting diode and the deviation of the crystal orientation distribution of the phosphor in the wavelength conversion member, and the light emitting diode having no deviation in the crystal orientation distribution of the phosphor in the wavelength conversion member That is, a light-emitting diode with higher brightness and no color unevenness can be provided.

As a result of producing high-intensity light-emitting diodes with no color unevenness according to the present invention, as light-emitting diodes for various applications such as image display devices and illumination devices typified by white light-emitting diode light sources for backlights of liquid crystal display panels. Applicable or applicable.

It is process drawing which shows the procedure of the analysis method of the deviation of the crystal orientation distribution of the crystalline particle in the composite member of this invention. It is sectional drawing which shows the structure of the light-emitting device like a light emitting diode to which the analysis method of the deviation of the crystal orientation distribution of this invention is applied. It is a figure which shows the bias | inclination of the crystal orientation distribution of (beta) -type sialon fluorescent substance in the measurement example 1. FIG. It is a figure which shows the bias | inclination of the crystal orientation distribution of (beta) type sialon fluorescent substance in the example 7 of a measurement. It is sectional drawing which shows the structure of the conventional light emitting diode.

1: Light-emitting device 2: Light-emitting light source 3: First lead frame 4: Second lead frame 5: Wavelength conversion member 6: Bonding wire 7: Resin 8: Phosphor 9: Cap

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows the procedure of a method for analyzing the deviation of the crystal orientation distribution of the crystalline particles in the composite member of the present invention.
As shown in FIG. 1, in the method for analyzing the deviation of the crystal orientation distribution of the crystalline particles in the composite member according to the present invention, first, in the imaging step ST1, the cross section of the crystalline particles in the composite member is imaged. .
In the determination step ST2, the individual orientations of crystal grains in the image created in the imaging step ST1 are determined.
In the analysis step ST3, an analysis for specifying the distribution of individual orientations determined in the determination step ST2 is performed.
Finally, in the analysis step ST4, the orientation distribution obtained as a result of the analysis in the analysis step ST3 is analyzed to analyze the bias of the crystal orientation distribution.
In addition, the composite member which is a measurement object of the present invention may be anything as long as it is a dispersed phase in which crystalline particles as a dispersoid are dispersed in a solid as a medium. As an example of the composite member, it may be a wavelength conversion member used for a white light-emitting diode, and the wavelength conversion member is composed of at least one kind of phosphor and resin, and the crystalline particles are phosphor, and the medium Is resin or glass. In the following description, the composite member will be described as a wavelength conversion member.

In imaging step ST1, a cross section of a wavelength conversion member, which is a composite member of a sealing resin and crystalline particles, is prepared by mechanical polishing and ion polishing, and then this cross section is imaged. This imaging can be performed using an apparatus that can observe the crystalline particles exposed in the cross section. For example, an image can be formed by introducing a cross section into a sample chamber of a scanning electron microscope and observing a secondary electron image of the cross section.

Next, in determination step ST2, the crystal orientation of the crystalline particles observed in the cross section is acquired and determined by an analyzer. As an apparatus for analyzing the crystal orientation, an apparatus using an electron backscatter diffraction image method (also called EBSD) is cited. An example of such an apparatus is obtained by adding a detector capable of acquiring an electron backscatter diffraction image to a scanning electron microscope apparatus. When the electron backscatter diffraction image method is performed with a scanning electron microscope, the spatial resolution is about 0.1 μm, and the resolution for determining the orientation of the observation sample is about 1 °.
In the electron backscatter diffraction image method, a two-dimensional geometric pattern called a Kikuchi pattern corresponding to the crystal structure and crystal orientation of crystal grains is obtained.

As an example of the analysis step ST3, the analysis is performed using an analysis program that can analyze the crystal orientation based on the Kikuchi pattern acquired in the determination step ST2. That is, the crystal orientation distribution can be obtained by acquiring the Kikuchi pattern of crystal grains, specifying the crystal orientation using an analysis program, and repeating this with a plurality of crystal grains.
Here, the greater the number of crystalline particles specifying the crystal orientation, the better the statistical analysis accuracy. However, if the number of crystalline particles is 50 or more, sufficient data for analysis can be obtained.

Next, the analysis step ST4 for analyzing the deviation of the crystal orientation distribution will be described. The analysis step ST4 can also be executed using the electron backscatter diffraction image method.
When analyzing the deviation of the crystal orientation distribution by the crystal orientation distribution obtained in the analysis step ST3, the following orientation index can be used. The orientation index is defined by the following formula (1). That is, the orientation index can be obtained by dividing the cross-sectional area of the crystalline particles in which the crystal orientation serving as a bias index is recognized by the cross-sectional area of all the crystalline particles and multiplying by 100.
Orientation index (%) = ((cross-sectional area of crystalline particles in which the crystal orientation serving as a bias index is recognized) / (cross-sectional area of all crystalline particles)) × 100 (%) (1)
Here, when the crystalline particles have a columnar shape or a needle shape, the orientation of the normal direction of the crystal plane corresponding to the bottom surface or the column surface of the columnar or acicular particles is used as the crystal orientation serving as an index of deviation. Can do. The crystal orientation that serves as an indicator of the deviation may be within a predetermined angle range with respect to the normal direction of the crystal plane. Examples of the phosphor having a columnar shape include α-type sialon and β-type sialon.

Since the crystal structure of α-type sialon and β-type sialon has a hexagonal crystal form, the crystal orientation that serves as an index of crystal deviation is, for example, a predetermined angular range with respect to the normal direction of the bottom [0001] plane It can be. The predetermined angle range is, for example, ± 30 °.

The orientation index defined by the above equation (1) indicates the deviation of the crystal orientation distribution of the crystalline particles in the composite member, and the deviation of the crystal orientation distribution of the crystalline particles in the composite member can be evaluated.

Therefore, when the composite member is a wavelength conversion member in a light-emitting diode and the crystalline particles in the wavelength conversion member are phosphor particles, the above-described technique can be used to offset the crystal orientation distribution of the phosphor in the wavelength conversion member. It becomes possible to evaluate.

FIG. 2 is a cross-sectional view showing the structure of a light-emitting device 1 such as a light-emitting diode to which the method for analyzing the deviation of the crystal orientation distribution of the present invention is applied. As shown in FIG. 2, the light emitting device 1 of the present invention includes a light emitting light source 2, a first lead frame 3 on which the light emitting light source 2 is mounted, a second lead frame 4, a light emitting light source 2 and a first lead. A wavelength conversion member 5 that covers the frame 3 is included.

A recess 3b for mounting a light emitting diode chip as the light emitting light source 2 is formed in the upper part 3a of the first lead frame 3. The recess 3b has a substantially funnel shape in which the hole diameter gradually increases upward from the bottom surface, and the inner surface of the recess 3b is a reflecting surface. One electrode on the lower surface side of the light emitting diode chip 2 is die-bonded to the bottom surface of the reflecting surface. The other electrode formed on the upper surface of the light emitting diode chip 2 is connected to the surface of the second lead frame 4 via the bonding wire 6.

Further, as shown in FIG. 1, the light emitting device 1 is covered with a cap 9 made of resin or glass as a whole, the light emitting light source 2, the first and second lead frames 3, 4, the wavelength conversion member 5, and the bonding wire 6. Configured.

As the light emitting light source 2, a light emitting diode chip that generates light having a wavelength of 300 nm to 500 nm of blue light 3 from near ultraviolet can be used.

The wavelength conversion member 5 is composed of, for example, a resin material 7 such as a silicone resin and at least one kind of phosphor 8, and the phosphor 8 is dispersed in the resin material. The type of the phosphor 8 may be selected according to the color tone obtained by the color mixture of the light from the light emitting light source 2 and the light generated from the phosphor 8 that absorbs and excites the light from the light emitting light source 2. In order to obtain a desired mixed color light, one or a plurality of types of phosphors 8 can be used in combination.

The phosphor 8 has a particulate shape. Examples of such phosphor particles 8 include β-type sialon, α-type sialon, and CaAlSiN ₃ activated with Eu. These phosphors 8 have a columnar crystal shape such as a hexagon.

The β-type sialon phosphor 8 represented by the general formula: Si _6-z Al _z O _z N _8-z : Eu ²⁺ has a columnar shape, and the emission characteristics are green with a peak wavelength of 520 to 550 nm Exhibits luminescence.

_{_{_Formula: Ca m / 2 Si 12- (}} m + n) Al (m + n) N 16-n On: α -sialon phosphor 8 represented by ^{Eu 2+} likewise has a columnar shape, 550 nm as a light emitting property It exhibits yellow to orange light emission with a peak wavelength of ˜610 nm.

CaAlSiN ₃ : Eu also has a columnar shape, and exhibits red light emission having a peak wavelength of 630 to 650 nm as light emission characteristics.

According to the present invention, it is possible to analyze the deviation of the crystal orientation distribution of the crystalline particles in the composite member, which has been difficult in the past. In the industrial field where the crystal orientation distribution control of the crystalline particles in the composite member is necessary, it becomes possible to analyze the deviation of the crystal orientation distribution. Therefore, it can be used in various industrial fields such as the semiconductor field.

In particular, by applying the present invention to the analysis of the crystal orientation of the phosphor 8 particles in the wavelength conversion member 5 in the light emitting diode 1, the crystal orientation distribution of the phosphor 8 in the wavelength conversion member 5 can be controlled. . Thereby, it is possible to provide the light-emitting diode 1 in which the crystal orientation distribution of the phosphor in the wavelength conversion member is not biased, that is, the light-emitting diode 1 having higher luminance and no color unevenness. Such a high-performance light-emitting diode 1 can be used for an image display device or a lighting device typified by a white light-emitting diode 1 for backlight of a liquid crystal display panel.

Next, based on an Example, this invention is demonstrated still in detail.
In the embodiment, the crystal orientation distribution of the phosphor particles 8 in the wavelength conversion member 5 composed of the phosphor particles 8 in the light emitting diode 1 and the resin layer 7 that seals the phosphor particles 8 as the crystalline particles of the composite member. Evaluated.

A commercially available light-emitting diode package (I-CHIUN PRECIS10N INDUSTRY CO., LTD, model SMD5050), blue light-emitting diode chip 2 (Genesis Photonics Inc., MODEL RIS45A19), and wavelength conversion member 5 are prepared. Was made. The wavelength conversion member 5 includes a CaAlSiN ₃ : Eu phosphor as a red phosphor 8 and a β-sialon phosphor 8 manufactured in-house as a green phosphor with a silicone resin layer 7 (manufactured by Dow Co., Toray, model number EG6301). ) And coated on a blue light emitting diode chip. The CaAlSiN ₃ : Eu phosphor 8 was synthesized by the manufacturing method disclosed in Patent Document 5. As shown in Table 1 below, in the measurement examples 1 to 8, the particle form of the phosphor 8 was adjusted so that the crystal orientation distribution of the phosphor 8 in the wavelength conversion member 5 was different.

White light was emitted by applying a forward voltage to the manufactured light emitting diode 1 and flowing a predetermined current. White light is generated by a color mixture of blue light from the blue light emitting diode 1 and red and green light emitted when the blue light is applied to the two phosphors 8. The luminous intensity of white light was measured using an ultrasensitive instantaneous multi-photometry system (manufactured by Otsuka Electronics Co., Ltd., MCPD-7000).
The luminous intensity of the light-emitting diode 1 was calculated as a relative value with the luminous intensity of the light-emitting diode 1 in Measurement Example 1 as 100%.

Next, the deviation of the crystal orientation distribution of the phosphor 8 in the wavelength conversion member 5 was analyzed by the method shown in FIG.
As an imaging process for imaging the cross section of the crystalline particles in the composite member, the cross section of the light emitting diode 1 was exposed by mechanical polishing and Ar ⁺ ion polishing.
Next, the cross section of the light-emitting diode 1 was observed with a field emission scanning electron microscope (FE-SEM, JEOL Ltd., JSM-700IF type), and under the condition of an acceleration voltage of 15 kV, the sealing resin layer 7 An image of a cross section of the crystalline particles blended in was obtained.

In the determination process for determining the individual orientations of crystal grains in the obtained image, an electron backscatter diffraction image measurement device (EDAX-TSL, type OIM) was added to the field emission scanning electron microscope. A device was used. The crystal orientation was measured by this crystal orientation analysis system.

The crystal orientation measurement conditions are shown below.
Accelerating voltage: 15kV
Working distance 15mm
Sample tilt angle: 70 °
Measurement area: 80 μm × 200 μm
Step width: 0.2 μm
Measurement time: 50 msec / step Number of data points: about 400,000 points Note that the measurement conditions are not limited to this, and can be appropriately determined according to the sample form and the apparatus performance.

Next, as an analysis process to analyze and identify the orientation distribution determined by the determination process, analysis software (EDAX-TSL) that can analyze the crystal orientation from the Kikuchi pattern obtained by electron backscatter diffraction imaging The crystal orientation was analyzed using OIM ™ Ver5.2).

As an analysis step of analyzing the crystal orientation distribution obtained in the analysis step and analyzing the deviation of the crystal orientation distribution, the orientation index defined by the above equation (1) was analyzed. Here, the analysis was conducted focusing on the β-type sialon phosphor 8 as the crystalline particles.

Since the crystal particles of the β-type sialon phosphor 8 have a hexagonal columnar shape, the crystal orientation serving as a bias index was set as follows. The orientation in the direction perpendicular to the crystal plane having an inclination of −30 ° to + 30 ° with respect to the normal direction of the bottom surface ([0001] plane) of the β-type sialon particles was used as an indicator of the bias. That is, the desired orientation index can be expressed by the following equation (2).
Orientation index (%) = ((cross-sectional area of particles having a β-type sialon [0001] crystal plane and a crystal orientation of ± 30 ° in the normal direction) / (cross-sectional area of β-type sialon particles)) × 100% ( 2)

By the above procedure, the crystal orientation deviation of the crystalline particles in the sealing resin layer 7, here, the crystal orientation deviation of the phosphor 8 particles in the wavelength conversion member 5 in the light emitting diode 1 was measured.

As described above, the crystal plane that serves as an index of the crystal orientation deviation can be set to an appropriate crystal plane and range in the properties of the composite member to be analyzed.

(Measurement Example 1)
The luminous intensity of the light emitting diode 1 of Measurement Example 1 was measured. With this value as 100%, the luminous intensity of other measurement examples 2 to 8 was measured.

FIG. 3 shows the deviation of the crystal orientation distribution of the β-type sialon phosphor 8 in Measurement Example 1. A cross-section in which a region indicated by hatching is a β-type sialon [0001] crystal plane and a crystal plane of ± 30 degrees with respect to the normal direction thereof, and a β-type in which other crystal planes are exposed in a region without hatching A sialon phosphor 8. The orientation index calculated from the above equation (2) was 22.0%.

(Measurement example 2)
The luminous intensity of the light-emitting diode 1 of Measurement Example 2 was 98.2%. The orientation index indicating the deviation of the crystal orientation distribution of the β-type sialon phosphor 8 analyzed by the same method as in Measurement Example 1 was 19.10%.

(Measurement Example 3)
The luminous intensity of the light-emitting diode 1 of Measurement Example 3 was 102.8%. The orientation index indicating the deviation of the crystal orientation distribution of the β-type sialon phosphor 8 analyzed by the same method as in Measurement Example 1 was 16.3%.

(Measurement Example 4)
The luminous intensity of the light-emitting diode 1 of Measurement Example 4 was 100.9%. The orientation index indicating the deviation of the crystal orientation distribution of the β-type sialon phosphor 8 analyzed by the same method as in Measurement Example 1 was 3.3%.

(Measurement Example 5)
The luminous intensity of the light-emitting diode 1 of Measurement Example 5 was 106.5%. The orientation index indicating the deviation of the crystal orientation distribution of the β-type sialon phosphor 8 analyzed by the same method as in Measurement Example 1 was 13.3%.

(Measurement Example 6)
The luminous intensity of the light-emitting diode 1 of Measurement Example 6 was 103.8%. The orientation index indicating the deviation of the crystal orientation distribution of the β-type sialon phosphor 8 analyzed by the same method as in Measurement Example 1 was 14.1%.

(Measurement Example 7)
The luminous intensity of the light-emitting diode 1 of Measurement Example 7 was 108.9%.
FIG. 4 shows the deviation of the crystal orientation distribution of the β-type sialon phosphor 8 in Measurement Example 7, and the method for displaying the crystal orientation and the like is the same as in FIG. The orientation index indicating the deviation of the crystal orientation distribution of the β-type sialon phosphor 8 analyzed by the same method as in Measurement Example 1 was 11.3%.

(Measurement Example 8)
The luminous intensity of the light-emitting diode 1 of Measurement Example 8 was 104.1%. The orientation index indicating the deviation of the crystal orientation distribution of the β-type sialon phosphor 8 analyzed by the same method as in Measurement Example 1 was 7.3%.

Table 1 summarizes the results of the luminous intensity and orientation index of the light-emitting diodes 1 measured in Measurement Examples 1-8.

According to the present invention, it was possible to determine the deviation of the crystal orientation distribution of the β-type sialon phosphor 8 in the wavelength conversion member 5.

Furthermore, the present invention can be applied not only to the deviation of the crystal orientation distribution of the β-type sialon phosphor 8 in the wavelength conversion layer but also to the analysis of the deviation of the crystal orientation of the crystalline particles in the general resin layer 7 material.

The present invention is not limited to the above embodiment, and various modifications are possible within the scope of the invention described in the claims, and it goes without saying that these are also included in the scope of the present invention. Nor.

Claims

An imaging step of imaging the cross-section of the crystalline particles in the composite member;
A determination step of determining individual crystal orientations of the crystal particles in the image created by the imaging step;
An analysis step for specifying the distribution of crystal orientation determined by the determination step;
An analysis step of analyzing the distribution of the crystal orientation distribution by analyzing the distribution obtained in the analysis step, and analyzing the bias of the crystal orientation distribution.
2. The method for analyzing a deviation in crystal orientation distribution according to claim 1, wherein the determination step and the analysis step are performed using an electron backscatter diffraction image method.
In the determination step, the crystal orientation of the crystalline particles appearing in the cross section of the sealing resin is specified, and in the analysis step, the cross-sectional area of the crystalline particles in which the crystal orientation serving as a bias index is recognized The deviation of the crystal orientation distribution according to claim 2, wherein an orientation index obtained by dividing by the cross-sectional area of the crystalline particle and further multiplied by 100 is calculated, and the orientation index is obtained as a deviation of the crystal orientation distribution. Analysis method.
The crystalline particles have a columnar crystal surface composed of a bottom surface and a column surface, and the crystal orientation serving as the deviation index is a normal direction of the crystal surface corresponding to the bottom surface or the column surface. The method for analyzing a deviation in crystal orientation distribution according to claim 3, wherein
The crystalline particles have a hexagonal shape, and the crystal orientation serving as an index of the deviation is set within a predetermined angle range with respect to a normal direction of a crystal plane corresponding to the bottom surface or the column surface. The method for analyzing a deviation in crystal orientation distribution according to claim 4, wherein