JP4737218B2 - Method for manufacturing light emitting device - Google Patents

Description

The present invention relates to a light emitting device, and in particular, it is possible to prevent deformation of bumps of a light emitting element, short circuit between bumps, and the like, which are caused by the pressure applied when sealing a sealing member is applied to the light emitting element. The present invention relates to a light emitting device.

As a typical structure of a light-emitting device using an LED (light-emitting diode) as a light source, there is one that covers a predetermined range of an LED element and a lead portion with a light-transmitting sealing material. As this sealing material, there are resins such as epoxy and silicon, and glass, but resins are generally used in terms of moldability, mass productivity, and cost.

By sealing the LED element with a sealing resin, the design freedom and productivity of the light emitting device are excellent, but the optical and chemical characteristics of the sealing resin are deteriorated by the light emitted from the LED element, As a result, reducing the luminous efficiency of the light emitting device has been regarded as a problem.

It is known that a sealing resin material (for example, an epoxy resin) gradually turns yellow by receiving strong light emitted from an LED element, and the resin material is colored. When such coloring occurs, there is a problem that light emitted from the LED element is absorbed to reduce the light output of the light emitting device, and the influence of coloring appears on the output light.

As a solution to such a problem, there is a light emitting device in which an LED element is sealed with a glass layer having moisture resistance, and other portions are sealed with a resin (for example, see Patent Document 1).

FIG. 6 shows a light-emitting device disclosed in Patent Document 1. The light emitting device 200 includes a wiring conductor 20
1 and 202, a cup part 203 formed on the wiring conductor 202, an LED element 204 bonded to the bottom 203A in the cup part 203, an electrode part (not shown) of the LED element 204, and the wiring conductors 201 and 202. A wire 205 for electrically connecting a predetermined portion of the cup portion 2 and the cup portion 2
03, a glass layer 206 that seals the LED element 204 provided in 03, a fluorescent material 206A contained in the glass layer 206, and a sealing resin 207 that is molded into a cannonball shape to seal the whole and has light transmittance. And have. The fluorescent material 206A is used for the glass layer 2 to perform wavelength conversion.
The wavelength of the light emitted from the LED element 204 is converted by the fluorescent material 206A.

According to such a configuration, the glass layer 2 in which the LED element 204 is injected into the cup portion 203.
Since it is surrounded by 06, light attenuation due to yellowing or coloring can be reduced. Further, moisture permeation can be prevented and deterioration of the phosphor can be prevented.

In recent years, high-power LEDs have been developed, and a high-power type of several watts has already been commercialized. LED is characterized by low heat generation, but high output (high brightness) type L
Since a large current flows through the ED element, heat generation at a level that cannot be ignored occurs. For this reason, it is necessary to replace the sealing member with a conventional resin material and to use a sealing material excellent in heat resistance, for example, a glass material.
Japanese Patent Laid-Open No. 11-204838 (FIG. 1)

However, according to the conventional light emitting device, when the sealing member is made of a glass material, since the glass material has a higher viscosity than the resin material, a high-pressure press is used for the sealing. When the sealing process is performed, a pressure or stress is applied to the LED elements, and the LED elements are connected by a pump, and the pump is likely to be deformed (collapsed) or moved, or short-circuited between the pumps.

Therefore, an object of the present invention is to prevent the deformation, movement, short circuit between bumps, etc. of the light emitting element caused by the pressure applied by the sealing member during the sealing being applied to the light emitting element. An object of the present invention is to provide a light emitting device.

In order to achieve the above object, the present invention
In manufacturing a light-emitting device including a flip-type light-emitting element, a power supply member on which the light-emitting element is mounted via a bump, and an insulating layer formed between the light-emitting element and the power supply member ,
Forming the insulating layer by dripping or filling;
Light emission that forms a light- transmitting glass sealing member that seals the exposed surface of the insulating layer, the upper surface of the power supply member, and the light-emitting element by pressing the glass sheet with a pressure press at a predetermined temperature and atmosphere. An apparatus manufacturing method is provided.

In the method for manufacturing the light emitting device,
It is preferable that the insulating layer is mixed with a phosphor and is provided so as to cover a side surface of the light emitting element or a side surface and an upper surface.

In the method for manufacturing the light emitting device,
The power supply member is a substrate portion having a wiring layer electrically connected to the light emitting element,
It is preferable that the sealing member seals the wiring layer of the substrate portion.

In the method for manufacturing the light emitting device,
The insulating layer preferably contains at least one of diamond, BN, SiC, or AlN.

According to the light emitting device of the present invention, since the insulating layer is filled on the bump mounting surface side of the light emitting element, the pressure applied to the LED element at the time of sealing is blocked by the insulating layer. Deformation, movement, short circuit between bumps, and the like can be prevented.

FIG. 1 is a cross-sectional view showing a configuration of a light emitting device according to a first embodiment of the present invention. The light emitting device 10 includes a substrate portion 11 as a power supply member, and bumps 12 a and 12 b made of at least a pair of Au for supplying power, and an LED element 12 mounted on the upper surface of the substrate portion 11.
An insulating layer 13 filled between the lower surface of the LED element 12 and the substrate portion 11, and the LED element 12
And the sealing member 14 formed so that the upper surface of the board | substrate part 11 may be covered is comprised.

The substrate unit 11 includes a ceramic substrate 11a, wiring layers 11b, 11c, 11d, and 11e formed on the upper surface of the ceramic substrate 11a with a predetermined pattern, and a wiring layer 11f formed on the lower surface of the ceramic substrate 11a with a predetermined pattern. 11g, an Au plating film 11h coated on the surface of the wiring layer 11c, an Au plating film 11i coated on the surface of the wiring layer 11d, an Au plating film 11j coated on the surface of the wiring layer 11f, and a wiring A coated on the surface of the layer 11g
A u-plated film 11k, a through hole 11l for connecting the wiring layer 11b and the wiring layer 11f, and a through hole 11m for connecting the wiring layer 11d and the wiring layer 11g are provided.

The ceramic substrate 11a is made of, for example, a glass-containing Al2O3 material (coefficient of thermal expansion: 13.2 × 10
-6 / ° C). The wiring layers 11c, 11d, 11f, and 11g function as electrodes for supplying power. Further, the Au plating films 11h, 11i, 11j, and 11k are provided in order to improve connectivity, conductivity, and corrosion resistance. In addition, the board | substrate part 11 is LE.
Before mounting the D element 12, the wiring layers 11b to 11g, the Au plating films 11h, 11i, and 11
j and 11k and through holes 11l and 11m are formed in the ceramic substrate 11a in advance.

The LED element 12 is configured by using a semiconductor such as GaN or AlInGaP, and the chip size is 0.3 × 0.3 mm (standard size), 1 × 1 mm (large size), or the like. The LED element 12 has power supply electrodes 12 a and 12 b on the lower surface, and the electrodes 12 a and 12 b are soldered onto a predetermined wiring layer of the substrate portion 11.

The insulating layer 13 is formed of a silicon-based material or an insulating material containing diamond, BN, SiC, or AlN powder. When silicon resin is used as the silicon material,
Due to the high temperature associated with the sealing of the sealing member 14, the chemical bond is broken, so that it becomes SiO ₂ and functions as an insulator having heat resistance. Further, instead of SiO ₂ formed of silicon resin, ceramic formed of Si-based or Ti-based alkoxide can be used. Diamond has high thermal conductivity. BN, SiC, and AlN are inferior in thermal conductivity to diamond but are inexpensive. Further, diamond, BN, and SiC are transparent or white and have a feature of little light absorption.

The sealing member 14 is formed using a glass material having translucency and a low melting point, for example, “PSK100” (thermal expansion coefficient: 11.4 × 10 ⁻⁶ / manufactured by Sumita Optical Glass Co., Ltd.). ℃)
Can be used. In the experiments of the inventors, in order to obtain a good bonding between the ceramic and the glass, the ceramic substrate 11a and the sealing member 14 are approximately equal in thermal expansion coefficient (ratio of thermal expansion coefficient difference is within 15%). Here, the ratio of the thermal expansion coefficients is 0.86.

  Hereinafter, assembly of the light emitting device 10 will be described.

After positioning the Au bumps 12a and 12b so as to be placed on the wiring layers 11c and 11d and disposing the LED element 12 on the substrate portion 11, the insulating layer 13 is formed by dropping, filling or the like.

Next, the sealing member 14 made of a glass material is sealed on the LED element 12, the exposed surface of the insulating layer 13, and the exposed surface of the substrate portion 11. A mold is used for sealing the sealing member 14, and it is formed into a semicircular shape as shown in FIG. At the time of sealing, the silicon material as the insulating layer 13 is changed to SiO ₂ , and the lower surface of the LED element 12 and the bumps 12a and 12b are fixed. Therefore, deformation of the bumps 12a and 12b, a short circuit between the bumps, etc. Is avoided. Thus, the light emitting device 10 is completed.

In the light emitting device 10, for example, if the wiring layer 11f is on the anode side of the LED element 12, the plus side of a DC power source (not shown) is connected to the wiring layer 11f, and the minus side is connected to the wiring layer 11g. . When a forward voltage is applied to the LED element 12 via a bump 2 electrically connected to a p-type electrode and an n-type electrode (not shown), hole and electron carrier recombination in the active layer of the LED element 12 Occurs and emits light, and the output light is LED
Radiated outside the element 12. Most of this light is transmitted through the sealing member 14 and exits from the sealing member 14, and part of the light is reflected from the inner surface and exits from the sealing member 14.

According to the first embodiment described above, the following effects are obtained.
(1) By sealing the whole with the sealing member 14 made of a glass material, it is possible to reduce attenuation of light due to yellowing or coloring, which is a problem in resin sealing.
(2) Since the insulating layer 13 having heat resistance is provided on the lower side of the LED element 12, the sealing member 14 presses the bumps 12 a and 12 b with high heat when the sealing member 14 is sealed.
Will no longer cause damage. That is, it is possible to prevent the bumps 12a and 12b from being deformed or damaged due to the high heat and high pressure of the sealing member 14 and causing a short circuit between the bumps.
(3) When an insulating material containing diamond, BN, SiC, or AlN powder is used,
Since the effect of radiating the heat generated by the LED element 12 can be expected, the heat dissipation can be improved.

FIG. 2 is a cross-sectional view showing the configuration of the light emitting device according to the second embodiment. This light emitting device 2
0 is a metal lead type mounted on the lead frame using the submount 22;
LED element 21 provided with bumps 21a and 21b on the mounting surface, submount 22 on which LED element 21 is mounted, lead portions 23a and 23b as power supply members on which submount 22 is mounted, and lead portion Insulating layer 24 filled between the upper surfaces of 23 a and 23 b and the lower surface of LED element 21, lead portion 2 including the end of insulating layer 24 and the surface of LED element 21
And a sealing member 25 made of translucent glass for sealing the tip portions of 3a and 23b.

The submount 22 is made of, for example, high thermal conductivity AlN (aluminum nitride), and the wiring layer 22a connected to one of the bumps 21a is formed in a U shape over the upper surface, the side surface, and the lower surface. On the opposite side, the wiring layer 22b connected to the bump 21b is the upper surface,
It is formed so as to form a U shape over the side surface and the lower surface.

Further, the submount 22 can incorporate a circuit such as a Zener diode for preventing element destruction as needed. Further, instead of the wiring layers 22a and 22b, a wiring means by a combination of electrodes provided on the upper and lower surfaces and through-holes communicating the upper and lower electrodes may be used.

The lead portions 23a and 23b are made of copper-based or iron-based metal, and are formed as a part of a lead frame (not shown) so as to face the inner side of the belt-like portions on both sides with a predetermined gap.
A pair is assigned to each LED element. Part of the tip of the lead portions 23a and 23b is made thin so that a step is formed, and the submount 22 is formed on the step.
Is placed.

As the insulating layer 24, a silicon material or an insulating material containing diamond or AlN powder can be used as in the insulating layer 13 in the first embodiment. Formation process in which the chemical bond is broken when the sealing member 25 is sealed and the silicon material becomes SiO ₂ , and diamond, BN, SiC
Alternatively, the heat radiation effect when using an insulating material containing AlN powder is the same as that of the insulating layer 13.

As the sealing member 25, a glass material having translucency and a low melting point is used as in the above-described embodiment.

In the light emitting device 20, if the lead portion 23a is a positive (+) power supply terminal, the current supplied to the lead portion 23a passes through the lead portion 23a, the wiring layer 22a, and the bump 21a, and the anode of the LED element 21. Furthermore, the current flowing out of the cathode of the LED element 21 is
The LED element 21 flows by flowing through the bump 21b and the wiring layer 22b to the lead portion 23b.
Emits light.

  Hereinafter, assembly of the light emitting device 20 will be described.

First, the submount 22 in which the wiring layers 22a and 22b are formed in advance is prepared. Bumps 21a and 21b are formed at predetermined positions on the submount 22, the LED element 21 is mounted thereon, the bumps 21a and the wiring layer 22a, and the bumps 21b and the wiring layer 22b are electrically connected and mechanically. Fix it.

Next, the LED elements 21 mounted on the submount 22 are arranged in the recesses at the tips of the lead portions 23a and 23b so that the energization directions are matched. The LED element 21 is mounted on the submount 22.
After mounting, the submount 22 may be mounted in the lead portions 23a and 23b.

Next, a silicone material as the insulating layer 24 is filled between the lower surface of the LED element 21 and the upper surface of the submount 22 (this filling may be performed before the submount 22 is mounted on the lead portions 23a and 23b). good.). The glass sheet (not shown) for carrying in this state in a metal mold | die and forming the sealing member 25 is arrange | positioned in the upper direction and the downward direction of the LED element 21, and hemispherical by predetermined temperature and pressure press Mold. At the time of sealing, the silicone material is converted to SiO ₂ to form the insulating layer 24, and the lower surface of the LED element 21 and the bumps 12a and 12b are fixed. Thus, the light emitting device 20 is completed. Finally, the other ends of the lead portions 23a and 23b are separated from a lead frame (not shown) to be individualized into the individual light emitting devices 20.

According to the second embodiment described above, the lead portions 23a, 2 having excellent adhesion to the glass material.
Since 3b is used and the insulating layer 24 is provided below the LED element 21, the sealing member 25 does not damage the LED element 21 when the sealing member 25 is sealed. It is possible to prevent deformation, movement, short circuit, and the like. Furthermore, by sealing the whole with the sealing member 25 made of a glass material, it is possible to prevent the light from being attenuated due to yellowing or coloring as in the case where the sealing member is a resin material.

FIG. 3 is a cross-sectional view showing a light emitting device according to the third embodiment. The light emitting device 30
Similar to the second embodiment, it is a metal lead type mounted on a lead frame using a submount. Here, as in FIG. 2, only the configuration of the main part is shown, and the submount 32 is shown in a non-cross-sectional state. This embodiment differs from the second embodiment in the structure of the submount and the configuration and formation range of the insulating layer.

The light emitting device 30 includes an LED element 31 having bumps 31a and 31b provided on the mounting surface,
A submount 32 on which the LED element 31 is mounted, lead portions 33a and 33b as power supply members on which the submount 32 is mounted at the tip, and a phosphor 34a are mixed and the entire surface of the LED element 31 is covered. The insulating layer 34 is filled or dropped so as to cover it, and the sealing member 35 made of translucent glass that seals the tip portions of the lead portions 33 a and 33 b including the upper surface of the LED element 31.

The submount 32 is made of, for example, high thermal conductivity AlN (aluminum nitride), and electrodes 32a and 32b connected to the bumps 31a and 31b are formed on the mounting surface side of the LED element 31, and the opposite surface (lead) On the frame side surface), electrodes 32c and 32d for connection to the pair of lead portions 33a and 33b are formed. In order to connect the electrode 32a and the electrode 32c, and the electrode 32c and the electrode 32d, a through hole 32e,
32f is provided.

The lead portions 33a and 33b are made of a copper-based or iron-based metal, and are formed as a part of a lead frame (not shown) so as to be opposed to the inner side of the belt-shaped portions on both sides with a predetermined gap.
A pair is assigned to the D element. Part of the tip of the lead portions 33a and 33b
It is made thin so that a step is generated, and the submount 32 is placed on this step portion.

The insulating layer 34 is mainly made of a silicone material, and a phosphor 34a is mixed therewith. In the case of the insulating layer 13, the generation process in which the chemical bond of the silicone material is cut to become SiO ₂ when sealing the sealing member 25 and the insulating material containing diamond or AlN powder is used. It is the same.

For example, when the LED element 21 emits blue light, the phosphor 34a uses Ce (cerium): YAG (yttrium, aluminum, garnet) having a characteristic of emitting yellow light when excited by the blue light.

The sealing member 35 is made of a glass material having translucency and a low melting point as in the above-described embodiments.

In the light emitting device 30, if the lead portion 33a is a positive (+) power supply terminal, the current supplied to the lead portion 33a causes the lead portion 33a, the electrode 32c, the through hole 32e, the electrode 32a, and the bump 31a. Then, the LED element 31 flows to the anode of the LED element 31, and the current from the cathode of the LED element 31 flows to the lead portion 33b via the bump 31b, the electrode 32b, the through hole 32f, and the electrode 32d, so that the LED element 31 emits light. To do.

  Hereinafter, the assembly of the light emitting device 30 will be described.

First, the submount 32 in which the electrodes 32a to 32d and the through holes 32e and 32f are formed in advance is prepared. Bumps 31a and 31b are formed at predetermined positions on the submount 32, and the LED element 31 is mounted. Thereby, the LED element 31 is made to bump 31a, 31.
It is electrically connected to the electrodes 32a and 32b via b and is mechanically fixed at the same time.

Next, the LED elements 31 mounted on the submount 32 are arranged in the recesses at the tips of the lead portions 33a and 33b so that the energization directions are matched. Alternatively, the submount 32 is connected to the lead portion 33.
After mounting on a and 33b, the procedure which mounts the LED element 31 on the submount 32 may be sufficient.

Next, the insulating layer 34 mixed with the phosphor 34 a is dropped or filled so as to cover the upper surface, the side surface, and the upper surface of the submount 32.

Next, the glass sheet (not shown) for carrying in a metal mold | die and forming the sealing member 35 is L
The light emitting device 30 is completed when the ED element 31 is disposed above and below the ED element 31 and formed into a hemispherical shape by a pressure press under a predetermined temperature. At the time of this sealing, the silicon material is changed to SiO ₂ to form the insulating layer 34, and the lower surface of the LED element 31 and the bumps 31a and 31b are fixed, so that the deformation of the bump 12a, the short circuit between the bumps, and the like are avoided. The Eventually, the other ends of the lead portions 33a and 33b are separated from the lead frame and individualized into individual light emitting devices.

According to the above-described third embodiment, the following effects can be obtained.
(1) Since the insulating layer 34 is provided, when the sealing member 35 is sealed, the sealing member 35 is an LED.
Since the element 31 is not damaged, the bumps 31a and 31b are deformed, moved,
It is possible to prevent a short circuit or the like from occurring.
(2) Since the phosphor 34a is mixed in the insulating layer 34, light absorption by the electrode on the lead portion (or the wiring layer on the submount) can be reduced. Usually, Au plating is given to an electrode and a wiring layer. This Au plating has a high absorption rate of blue or violet light. However, by providing the phosphor-containing insulating layer 34, the wavelength of light emitted from the side surface of the LED element can be converted. Absorption can be prevented.
(3) Wavelength conversion can also be performed on light emitted from the upper surface of the LED element 31.
Moreover, by sealing the whole with the sealing member 35 made of a glass material, it is possible to prevent light attenuation due to yellowing or coloring as in the case where the sealing member is a resin material.

The submount 32 is replaced with the “U” -shaped wiring layers 22a, 2 shown in FIG.
A submount 22 having 2b may be used. Conversely, the submount 32 shown in FIG. 3 may be used instead of the submount 22 of FIG.

FIG. 4 is a plan view showing a bump forming surface of a standard size LED element. This LED element 31 is a 0.3 mm square LED element, and is mounted on the large pattern 43, a small pattern 42 mounted with a pump 41 connected to the n electrode, a large pattern 43 connected to the p electrode. Pumps 44a and 44b are provided. As the LED element 31 becomes a higher output type, a larger current flows. Therefore, the number of pumps on the p-electrode side is made plural so that a large current capacity can be accommodated.

FIG. 5 is a plan view showing a bump forming surface of the large-size LED element. The LED element 31 is a 1 mm square LED element, and includes a wiring pattern 54 provided with bumps 52a and 52b and a wiring pattern 55 provided with bumps 53a to 53p. Large-size LED elements have a larger light emitting area than the standard size, and thus a larger current flows. Therefore, in order to achieve uniform light emission on the light emitting surface, a plurality of bumps serving as electrode contacts are provided in accordance with the shape areas of the wiring patterns 54 and 55.

As shown in FIGS. 4 and 5, in an LED element that is electrically connected via bumps, the bumps are easily crushed by the temperature and pressure during glass sealing. In particular, as shown in FIG. 5, in the case of having a large number of bumps 53a to 53p, since the distance between the bumps approaches, a short circuit is more likely to occur when the bump is deformed. For such an LED element 31, the insulating layer 34 covers the bump forming surface to ensure insulation between the bumps and withstands the pressure at the time of glass sealing, thereby suppressing the deformation of the bumps 53 a to 53 p. As a result, the sealing member 35 can be formed from a glass material.

In the above-described embodiments, the bumps 12a and 12b made of Au have been described. However, the bumps are not limited to Au, and may be bumps formed of solder. Also, not only bumps,
Solder plating formed on the electrode may be used. “PSK10” manufactured by Sumita Optical Glass Co., Ltd.
“0” is a sealing process at a temperature exceeding 400 ° C., and the glass viscosity at the time of processing is high, so that the Au bumps are crushed. On the other hand, the hybrid low melting point glass with inorganic / organic mixture can be sealed at a lower temperature, but if the melting point is lower than the sealing temperature, such as a solder bump, a short circuit between the electrodes occurs even at a small pressure. . The present invention is effective for this.

Further, in each of the above-described embodiments, the LED elements 12, 3 in the sealing members 14, 25, 35 are provided.
A phosphor layer for wavelength conversion can also be formed on the top of 2.

Further, in each of the above-described embodiments, the number of LED elements disposed in one sealing member is one, but a multi-light-emitting type light emitting device having two or more LED elements is provided. You can also The plurality of LED elements to be mounted may have a configuration in which a plurality of LED elements having different emission colors are provided or a configuration in which a plurality of LED elements having the same emission color are provided. Furthermore, as a drive form of the LED element, all of the plurality of LED elements may be connected in parallel or in parallel in units of groups, may be connected in series in a plurality of units, or all may be connected in series.

Moreover, although the dome-shaped structure was shown as the shape of the sealing members 14, 25, and 35, the present invention is not limited to the illustrated shape, a shape without a lens portion, a polygon, a cylindrical shape, and the like. , Can be any shape.

Furthermore, the molding of the sealing members 14, 25, and 35 is not limited to a molding method using a pressure press using a glass sheet, and other sealing methods may be used.

It is sectional drawing which shows the structure of the light-emitting device which concerns on the 1st Embodiment of this invention. It is sectional drawing which shows the structure of the light-emitting device which concerns on 2nd Embodiment. It is sectional drawing which shows the structure of the light-emitting device which concerns on 3rd Embodiment. It is a top view which shows the bump formation surface of the LED element of a standard size. It is a top view which shows the bump formation surface of a large sized LED element. It is sectional drawing which shows the structure of the conventional light-emitting device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Light-emitting device 11 Board | substrate part 11a Ceramic substrate 12 LED element 13 Insulating layer 14 Sealing member 20 Light-emitting device 21 LED element 22 Submount 24 Insulating layer 25 Sealing member 30 Light-emitting device 31 LED element 32 Submount 34 Insulating layer 34a Phosphor 35 Sealing member 41 Pump 42 Small pattern 43 Large pattern 54 Wiring pattern 55 Wiring pattern

Claims (4)

In manufacturing a light-emitting device including a flip-type light-emitting element, a power supply member on which the light-emitting element is mounted via a bump, and an insulating layer formed between the light-emitting element and the power supply member ,
Forming the insulating layer by dripping or filling;
Forming a light-transmitting glass sealing member that seals the exposed surface of the insulating layer, the upper surface of the power supply member, and the light-emitting element by pressing the glass sheet with a pressure press at a predetermined temperature and atmosphere; A method of manufacturing a light emitting device. The method for manufacturing a light-emitting device according to claim 1 , wherein the insulating layer is provided so as to cover a side surface of the light-emitting element, or a side surface and an upper surface, together with a phosphor mixed therein. The power supply member is a substrate portion having a wiring layer electrically connected to the light emitting element,
The sealing member, the method of manufacturing the light emitting device according to claim 1 or 2, wherein sealing the wiring layer of the substrate portion. The insulating layer, diamond, BN, SiC or the method of manufacturing the light emitting device according to claim 1 which contains at least one of AlN in any one of 3,.

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