JP2005216898A - Wavelength transducer, light source and method of manufacturing light source - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wavelength transducer which is manufactured with a highly manufacturing yield and a low cost, and also to provide a light source using the wavelength transducer and a method of manufacturing the light source. <P>SOLUTION: The light source 100 includes a stem 101 made of a conductive quality of the material, a semiconductor layer 102 provided on the front surface of the stem 101, the wavelength transducer 103 formed in the part of the front surface of the semiconductor layer 102, and two electrodes 104, 105 provided on the front surface of the stem 101 of the side in which the semiconductor layer 102 is not formed. And, the wavelength transducer 103 is made of a base metal substrate 106 containing impurities 151. It has an impurity high concentration region 103a and an impurity low concentration region 103b in the substrate side of the base metal substrate 106. The visible light which the semiconductor layer 102 emits, is irradiated, and the impurity high concentration region 103a and the impurity low concentration region 103b respectively emit lights having different wavelengths. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a wavelength conversion element, a light source including the wavelength conversion element, and a method for manufacturing the light source. More specifically, the present invention relates to a light-emitting element formed of a semiconductor such as a light-emitting diode. A wavelength conversion element for converting light emitted by a semiconductor layer in the scope and specification into light having a wavelength different from that of the light, a light source including the wavelength conversion element, and The present invention relates to a method for manufacturing a light source.

  In recent years, a multicolor light emitting device, that is, a blue light emitting diode (hereinafter referred to as “blue LED”), a red light emitting diode (hereinafter referred to as “red LED”), and a green light emitting diode (hereinafter referred to as “green light emitting diode”) on one stem. A light emitting element (hereinafter referred to as a “full color LED”) in which an “LED” is disposed has attracted attention. For example, in Patent Document 1, as shown in FIG. 8, a pair of blue LED chip 401 and red LED chip 402 are provided on a stem 408 having four leg pins 404, 405, 406, and 407 serving as electrodes. A full color LED 400 in which a green LED chip 403 is arranged is disclosed. By applying a voltage between the foot pin 406 and the foot pins 404, 405, 407, each blue LED chip 401 emits blue light, the red LED chip 402 emits red light, and the green LED chip 403 Emits green light.

Hereinafter, the structure of the full color LED 400 will be described. Each LED chip includes an n-layer electrode (not shown) and a p-layer electrode (not shown) on the back surface, each n-layer electrode is connected to a foot pin 406, and each p-layer electrode is a foot pin. 404, 405 and 407 are connected. First, the connection between the foot pin 406 and each n-layer electrode will be described. The leg pin 406 is electrically connected to the stem 408, and the back surface of the red LED chip 402 and the back surface of the green LED chip 403 are formed of a conductive material. Therefore, as long as the red LED chip 402 and the green LED chip 403 are bonded to the stem 408 using a conductive adhesive such as solder, the n-layer electrode of the red LED chip 402 and the n-layer electrode of the green LED chip 403 are used. Is electrically connected to the foot pin 406. On the other hand, since the back surface of each blue LED chip 401 is not formed of a conductive material, the back surface of each blue LED chip 401 is etched, and then an ohmic electrode (not shown) is formed on the etched portion. By attaching the ohmic electrode and the stem 408 using a gold wire (not shown), the n-layer electrode of each blue LED chip 401 is electrically connected to the foot pin 406. Connected. Next, connection between the foot pins 404, 405, and 407 and each p-layer electrode will be described. The foot pins 404, 405, 407 and the stem 408 are not electrically connected. Therefore, the p-layer electrode of each blue LED chip 401, the p-layer electrode of the red LED chip 402, and the p-layer electrode of the green LED chip 403 are connected to each other by connecting the p-layer electrode and the stem 408 using a gold wire. 404, 405, 407 are electrically connected. Thus, the blue LED chips 401 and 401, the red LED chip 402 and the green LED chip 403 and the foot pins 404, 405, 406 and 407 are electrically connected. As a result, the foot pins 404, 405 and 407 and the foot pins are connected. It is described that red light, blue light, and green light are emitted when an external voltage is applied to 406.
JP-A-6-151974

  However, the full color LED 400 disclosed in Patent Document 1 has a pair of blue LED chips 401, 401, a red LED chip 402 and a green LED chip 403 arranged on one stem 408. Therefore, when manufacturing the full-color LED 400, three types of LED chips must be prepared, which is very expensive. In addition, four LED chips 401, 401, 402, and 403 must be mounted on the stem 408, which may complicate the mounting process and reduce the manufacturing yield.

  This invention is made | formed in view of this point, The place made into the objective is the light source using a wavelength conversion element, a wavelength conversion element, and a light source using a wavelength conversion element which can be manufactured with a high manufacturing yield and low cost. It is to provide a manufacturing method.

  The wavelength conversion element of the present invention comprises a base material substrate containing impurities, and emits light having a wavelength different from that of the visible light when irradiated with visible light.

  The wavelength conversion element includes a plurality of regions having different impurity concentrations in the substrate surface of the base material substrate, and the regions having different impurity concentrations have different wavelengths when irradiated with the visible light. It is preferable to emit the light having.

  Here, the substrate surface of the base material substrate is a surface having the largest area among the surfaces of the base material substrate.

  In the wavelength conversion element, the base material substrate may be formed of quartz glass, borosilicate glass, or glass containing silicon dioxide as a main component.

  In the wavelength conversion element, the base material substrate may be formed of sapphire or spinel.

  In the wavelength conversion element, the impurity is preferably Si.

  In the wavelength conversion element, the impurity is preferably a particle having a diameter of 1 nm to 10 nm.

In the wavelength conversion element, the base material substrate includes a region in which the impurity concentration is 1 × 10 ¹⁷ cm ⁻² or more and 3 × 10 ¹⁷ cm ⁻² or less in the substrate surface of the base material substrate and the impurity. And a region having a concentration of 1 × 10 ¹⁶ cm ⁻² or more and 3 × 10 ¹⁶ cm ⁻² or less.

  In the wavelength conversion element, it is preferable that the visible light is blue light, and emits red and green light when irradiated with the blue light.

  The light source of the present invention is a light source comprising a semiconductor layer that emits visible light, a wavelength conversion element provided on a part of the surface of the semiconductor layer, and an electrode that applies a voltage to the semiconductor layer. The semiconductor layer emits the visible light when the voltage is applied through the electrode, and the wavelength conversion element is formed of a base material substrate containing an impurity, and is irradiated with the visible light. It emits light having a wavelength different from that of the visible light.

  Further, in the light source, the wavelength conversion element includes a plurality of regions having different impurity concentrations in the substrate surface of the base material substrate, and the regions having different impurity concentrations when irradiated with the visible light include: Each emits light having a different wavelength.

  Further, in the light source, the base material substrate may be formed of glass mainly composed of quartz glass, borosilicate glass, or silicon dioxide.

  In the light source, the base material substrate may be formed of sapphire or spinel.

  In the light source, the impurity is preferably Si.

  In the light source, the impurities are preferably particles having a diameter of 1 nm to 10 nm.

  In the light source, the semiconductor layer may be formed of a group III nitride semiconductor or a group II-VI compound semiconductor.

In the light source, the wavelength conversion element may have an impurity concentration of 1 × 10 ¹⁷ cm ⁻² or more and 3 × 10 ¹⁷ cm ⁻² or less in a plane perpendicular to a direction in which the visible light is irradiated. It is preferable to include a certain region and a region in which the impurity concentration is 1 × 10 ¹⁶ cm ⁻² or more and 3 × 10 ¹⁶ cm ⁻² or less.

  In the light source, it is preferable that the visible light is blue light, and the wavelength conversion element emits red and green light when irradiated with the blue light.

  The first light source manufacturing method of the present invention includes a step of mixing impurities into a base material substrate, a step of placing the base material substrate on a part of a surface of a semiconductor layer, and the base material substrate of the semiconductor layer. An electrode is provided on the surface opposite to the side on which the semiconductor layer is formed, and the semiconductor layer emits visible light when a voltage is applied through the electrode and contains the impurities. The material substrate emits light having a wavelength different from that of the visible light when irradiated with the visible light.

  The second light source manufacturing method of the present invention includes a step of forming a semiconductor layer on a surface of a base material substrate, a step of mixing impurities into the base material substrate, a side of the semiconductor layer on which the base material substrate exists, And a step of providing an electrode on the surface on the opposite side, wherein the semiconductor layer emits visible light when a voltage is applied through the electrode, and the base material substrate containing the impurity includes the visible light Is emitted to emit light having a wavelength different from that of the visible light.

  In the first and second light source manufacturing methods, the step of mixing impurities into the base material substrate is preferably performed by an ion implantation method.

  Further, in the first and second light source manufacturing methods, the step of mixing impurities into the base material substrate includes a step of forming a region having a predetermined impurity concentration in a part of the substrate surface of the base material substrate. Forming a region having an impurity concentration different from the impurity concentration in the region having the predetermined impurity concentration in a portion of the substrate surface different from a part of the substrate surface of the base substrate. Is preferred.

  In the first and second light source manufacturing methods, the impurity is preferably Si.

  In the first light source manufacturing method, the base material substrate is preferably formed of quartz glass, borosilicate glass, or glass containing silicon dioxide as a main component.

  In the first and second light source manufacturing methods, the base material substrate is preferably formed of sapphire or spinel.

  In the first and second light source manufacturing methods, the semiconductor layer is preferably formed of a group III semiconductor or a group II-VI semiconductor.

  Further, in the first and second light source manufacturing methods, when the visible light is irradiated, impurities different from the impurity concentration in the region having the predetermined impurity concentration and the region having the predetermined impurity concentration can be obtained. It is preferable to emit light having a wavelength different from that of the region having the concentration.

  In the wavelength conversion element of the present invention, as long as impurities are mixed in the base material substrate, light having a wavelength different from that of the visible light is emitted when irradiated with visible light. Therefore, light having different wavelengths such as irradiation light and converted light is emitted without using a plurality of types of LED chips. Here, the irradiation light means visible light irradiated to the wavelength conversion element, and the conversion light means light emitted when the visible light is irradiated. Therefore, when the wavelength conversion element of the present invention is used, a light source can be manufactured at low cost, and the number of components of the light source is reduced, so that the manufacturing yield is improved. In the light source of the present invention, the semiconductor layer emits visible light, and the wavelength conversion element emits light having a wavelength different from that of the visible light when irradiated with the visible light. Therefore, in order to manufacture the light source of the present invention, it is only necessary to prepare the semiconductor layer and the wavelength conversion element of the present invention. Therefore, it is not necessary to prepare a plurality of types of LED chips, and it can be manufactured at low cost. Moreover, since a semiconductor layer and a wavelength conversion element may be formed on the stem, the manufacturing yield can be improved.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, embodiment shown below is an example of this invention and this invention is not limited to the following embodiment.

Embodiment 1
The first embodiment will be described below with reference to FIGS.

  In the present embodiment, the structure of the light source 100, the manufacturing method of the light source 100, and the mechanism by which the light source 100 emits light of a plurality of colors will be described. 1 is a schematic diagram of the light source 100 according to the present embodiment, FIG. 2 is a diagram for explaining a method of manufacturing the light source 100, and FIG. 3 is a diagram illustrating a wavelength and wavelength placed on a part of the surface of the semiconductor layer 102. FIG. 4 is an enlarged view of the conversion element 103, and FIG. 4 is a spectrum diagram of light emitted from the light source 100.

  First, the structure of the light source 100 will be described.

  As shown in FIG. 1, a light source 100 includes a stem 101, a semiconductor layer 102 provided on the surface of the stem 101, a wavelength conversion element 103 formed on a part of the surface of the semiconductor layer 102, and a semiconductor layer. And two electrodes 104 and 105 provided on the surface of the stem 101 on the side where 102 is not formed.

  The stem 101 is made of a conductive material, and electrically connects the electrodes 104 and 105 and the semiconductor layer 102.

The semiconductor layer 102, III-group whose general formula is expressed as _{B x Ga 1-xyz Al y} In z N (0 ≦ x ≦ 1,0 ≦ y ≦ 1,0 ≦ z ≦ 1,0 ≦ x + y + z ≦ 1) It includes at least one compound semiconductor layer, and emits blue light when voltage is applied through the electrodes 104 and 105.

The wavelength conversion element 103 is made of a base material substrate 106 (shown in FIG. 2) made of sapphire, and includes an impurity 151, specifically, Si (shown in FIG. 2) having a diameter of 1 nm to 10 nm. In the substrate surface of the base material substrate 106, a region having a high impurity concentration (hereinafter referred to as “impurity high concentration region”) 103a and a region having a low impurity concentration (hereinafter referred to as “impurity low concentration region”). 103b, the impurity concentration in the high impurity concentration region 103a is 1 × 10 ¹⁷ cm ⁻² or more and 3 × 10 ¹⁷ cm ⁻² or less, and the impurity concentration in the low impurity concentration region 103b is 1 × 10 ¹⁶ It is not less than cm ^{−2 and not} more than 3 × 10 ¹⁶ cm ⁻² . When the wavelength conversion element 103 is viewed from the side, as shown in FIG. 1, the high impurity concentration region 103a and the low impurity concentration region 103b are formed adjacent to each other. When the blue light emitted from the semiconductor layer 102 is irradiated, the high impurity concentration region 103a emits red light, and the low impurity concentration region 103b emits green light. Note that blue light is light having a peak wavelength of 440 nm or more and 480 nm or less in the spectrum, green light is light having a peak wavelength of 520 nm or more and 570 nm or less, and red light is peak wavelength. Is light of 620 nm or more and 670 nm or less.

  Here, the substrate surface of the base material substrate 106 is a surface parallel to the interface between the semiconductor layer 102 and the wavelength conversion element 103 in this embodiment. In general, blue light emitted from the semiconductor layer 102 can reach the high impurity concentration region 103a and the low impurity concentration region 103b, and light emitted from the high impurity concentration region 103a can be emitted from the low impurity concentration region 103b. So that the light emitted from the low concentration impurity region 103b can be emitted outside the light source 100 without being absorbed by the high concentration impurity region 103a. A high impurity concentration region 103a and a low impurity concentration region 103b are formed. Therefore, in the present embodiment, the high impurity concentration region 103a and the low impurity concentration region 103b do not have a stacked structure, that is, the surface perpendicular to the interface between the semiconductor layer 102 and the wavelength conversion element 103 is the surface of the base material substrate 106. It cannot be the substrate surface. For example, when the high impurity concentration region 103a and the low impurity concentration region 103b are stacked in this order, the high impurity concentration region 103a may absorb all blue light emitted from the semiconductor layer 102, and the light source 100 may have a high impurity concentration. This is because only red light emitted from the density region 103a is emitted. For example, in the case where the low impurity concentration region 103b and the high impurity concentration region 103a are stacked in this order, the low impurity concentration region 103b may absorb all of the blue light emitted from the semiconductor layer 102 and the low impurity concentration region 103b. This is because green light emitted from the concentration region 103b may be absorbed by the high impurity concentration region 103a, and the light source 100 does not emit any light. In any case, when the substrate surface of the base material substrate 106 is a surface perpendicular to the interface between the semiconductor layer 102 and the wavelength conversion element 103, the light source 100 does not act as a light source. A surface perpendicular to the interface with the conversion element 103 cannot be the substrate surface of the base material substrate 106.

  Although the wavelength conversion element 103 shown in FIG. 1 is hatched, it is hatched to clarify the difference between the high impurity concentration region 103a and the low impurity concentration region 103b in the drawing, and represents a cross section. It is not for hatching.

  The electrodes 104 and 105 apply an external voltage to the semiconductor layer 102 via the stem 101.

  Next, a method for manufacturing the light source 100 will be described.

First, as shown in FIG. 2A, a sapphire base material substrate 106 to be the wavelength conversion element 103 is prepared, and a mask 161 b is formed on the right half of the surface of the base material substrate 106. Here, the mask 161b is formed of a resist film or a protective film such as SiO ₂ or SiN _x .

Next, as shown in FIG. 2B, Si ions, which are impurities 151, are mixed into the base material substrate 106 by an ion implantation method. Thereafter, the mask 161b is removed. At this time, the acceleration voltage of the ion implantation is 50 keV or more and 200 keV or less, and the ion implantation amount is 1 × 10 ¹⁷ cm ⁻² or more and 3 × 10 ¹⁷ cm ⁻² or less. Here, when the mask 161b is formed, the impurity 151 is not mixed in the portion of the base material substrate where the mask 161b is formed on the surface. Therefore, the impurity 151 is the portion of the base material substrate 106 where the mask 161b is not formed on the surface. Will be injected. That is, as shown in FIG. 2C, the impurity 151 is mixed into the left half of the base material substrate 106, and as a result, the impurity high concentration region 103a is formed.

Subsequently, an ion implantation process is performed in which the above-described two processes are different from the mask formation location and ion implantation amount. That is, as shown in FIG. 2D, the mask 161a is formed on the surface of the base material substrate 106 where the mask 161b is not formed in the above process, that is, on the left half of the base material substrate 106. Then, Si ions 151 which are impurities are mixed into the base material substrate 106 by an ion implantation method. Thereafter, the mask 161a is removed. At this time, the acceleration voltage for ion implantation of Si ions is 50 keV or more and 200 keV or less. The ion implantation amount of Si ions is 1 × 10 ¹⁶ cm ⁻² or more and 3 × 10 ¹⁶ cm ⁻² or less, which is smaller than the ion implantation amount in the above process. Here, when the mask 161a is formed, the impurity 151 does not enter the portion of the base material substrate where the mask 161a is formed on the surface. Therefore, the impurity 151 enters the portion of the base material substrate 106 where the mask 161a is not formed. Since the ion implantation amount in this step is smaller than the ion implantation amount in the above step, the low impurity concentration region 103b is formed in the right half of the base material substrate 106 in this step.

  Subsequently, thermal annealing is performed in a nitrogen atmosphere at 700 ° C. or higher for 30 minutes on the base material substrate on which the high impurity concentration region 103a and the low impurity concentration region 103b are formed. Accordingly, the diameter of the impurity 151 mixed in the high impurity concentration region 103a and the low impurity concentration region 103b is 1 nm or more and 10 nm or less. Then, the wavelength conversion element 103 in which the high impurity concentration region 103a is formed in the right half of the base material substrate 106 shown in FIG. 2E and the low impurity concentration region 103b is formed in the left half can be manufactured.

Furthermore, large areas of the surface than the wavelength converting element 103, and _{B x Ga 1-xyz Al y} In z N (0 ≦ x ≦ 1,0 ≦ y ≦ 1,0 ≦ z ≦ 1,0 ≦ x + y + z ≦ 1 The semiconductor layer 102 including the semiconductor layer represented by (1) is prepared, the wavelength conversion element 103 is placed on the surface of the semiconductor layer 102, and is fixed using an ultraviolet curable resin (not shown) or the like. Thereby, as shown in FIG. 3, the wavelength conversion element 103 is provided on a part of the surface of the semiconductor layer 102. And the surface which opposes the surface in which the wavelength conversion element 103 is mounted among the surfaces of the semiconductor layer 102, and the surface of the flat cylindrical stem 101 are adhere | attached. As a result, the semiconductor layer 102 is formed on the surface of the stem 101, and the wavelength conversion element 103 is formed on a part of the surface of the semiconductor layer 102.

  Thereafter, electrodes 104 and 105 are provided on the surface of the stem 101 on the side where the semiconductor layer 102 and the wavelength conversion element 103 are not bonded. Thereby, the light source 100 shown in FIG. 1 can be manufactured. As described above, the light source 100 according to the present invention is manufactured at low cost because it is not necessary to prepare three types of light emitting diodes (hereinafter referred to as “LED”) unlike the conventional multicolor light emitting device. be able to. Further, since the semiconductor layer 102 may be bonded to the stem 101 and the wavelength conversion element 103 may be placed on a part of the surface of the semiconductor layer 102, as in the full-color LED 400 described in Patent Document 1. It is not necessary to bond and fix the four LED chips 401, 401, 402, and 403 to the stem 408, and the LED chips 401, 401, 402, and 403 can be easily manufactured, and a high manufacturing yield can be obtained at the time of mounting.

  Here, in the enlarged view of the semiconductor layer 102 and the wavelength conversion element 103 shown in FIG. 3, the wavelength conversion element 103 is hatched. As in the case of FIG. 1, the impurity high concentration region 103a and the impurity low concentration are shown. The hatching is performed to clarify the difference from the region 103b in the drawing, and is not the hatching for representing the cross section.

  Next, the mechanism by which the light source 100 emits multicolor light will be described.

  The semiconductor layer 102 emits blue light (peak wavelength is 470 nm) by applying a voltage to the semiconductor layer 102 via the electrodes 104 and 105. As shown in FIG. 1, since the wavelength conversion element 103 is formed on a part of the surface of the semiconductor layer 102, a part of the blue light emitted from the semiconductor layer 102 is emitted to the outside of the light source 100, The remaining blue light is applied to the wavelength conversion element 103. Then, the blue light irradiated to the wavelength conversion element 103 excites the impurities 151 included in the wavelength conversion element 103. Here, since the electronic state of sapphire forming the wavelength conversion element 103 is different when the concentration of the impurity 151 is different, the wavelength of the light emitted from the high impurity concentration region 103a and the wavelength of the light emitted from the low impurity concentration region 103b are Will be different. Specifically, as illustrated in FIG. 4, the light source 100 is configured to emit blue light emitted from the semiconductor layer 102 (peak wavelength is 470 nm, peak at the leftmost broken line in FIG. 4) and blue light emitted from the semiconductor layer 102. When irradiated, red light emitted from the high impurity concentration region 103a (peak wavelength is 650 nm, the peak of the broken line at the right end of FIG. 4) and green light emitted from the low impurity concentration region 103b (peak wavelength is 550 nm, FIG. 4). The light of the white color is emitted as a total composed of the peak of the broken line at the center of the center.

  Below, the effect which the wavelength conversion element 103 of this embodiment, the light source 100, and the manufacturing method of the light source 100 show | plays is shown.

  In the light source 100 in the present embodiment, the semiconductor layer 102 emits blue light, and the wavelength conversion element 103 emits red and green light by irradiating the blue light. Accordingly, in order to manufacture the light source 100, the semiconductor layer 102 and the wavelength conversion element 103 need only be prepared, and emit light of red, blue, and green as in the case of manufacturing a conventional multicolor light emitting element 3. There is no need to prepare a kind of LED chip. As a result, the light source 100 can be manufactured at low cost.

  In the conventional multicolor light emitting device, the blue light emitted from the blue LED chip is not absorbed by the red LED chip and the green LED chip, and the green light emitted by the green LED chip is absorbed by the red LED chip. In order to avoid this, it was necessary to mount on the stem while paying attention to the positional relationship between the red LED chip, the blue LED chip, and the green LED chip. Therefore, it is difficult to mount on the stem, and the production yield of the multicolor light emitting elements is not good. However, in the light source 100 in the present embodiment, the semiconductor layer 102 emits blue light, and part of the blue light becomes part of the light emitted from the light source 100. The remaining blue light is irradiated onto the wavelength conversion element 103 and absorbed by the impurities 151 in the wavelength conversion element 103, thereby emitting red and green light. Therefore, in order to manufacture the light source 100 of the present invention, the semiconductor layer 102 is bonded on the stem 101 and the wavelength conversion element 103 is placed on a part of the surface of the semiconductor layer 102. Therefore, it is not necessary to place the semiconductor layer 102 on the stem while paying attention to the positional relationship between the wavelength conversion element 103 and it can be manufactured very easily, and the manufacturing yield of the light source 100 is good.

  In addition, in order to change the wavelength of light emitted from the light source 100, the concentration of the impurity 151 in the wavelength conversion element 103 may be changed. Therefore, the concentration of ions implanted into the wavelength conversion element 103 may be changed. Therefore, the wavelength of light can be changed. Further, when a voltage is applied to the semiconductor layer 102, the light source 100 emits red, blue, and green light. Therefore, the electrode is formed by etching the back surface of the LED chip like a conventional multicolor light emitting element. It is not necessary to provide four electrodes. Thus, the manufacturing effort can be saved.

  In the manufacturing method of the light source 100 of the present embodiment, the impurity 151 is mixed into the wavelength conversion element 103 by using the ion implantation method, but this method is not limited to this. Any method can be used as long as the impurity 151 can be mixed into the wavelength conversion element 103 so that the high impurity concentration region 103a emits red light and the low impurity concentration region 103b emits green light. In the method of manufacturing the light source 100 of the present embodiment, the impurity low concentration region 103b is first formed after the high impurity concentration region 103a is formed. However, the order is not limited to this, and the impurity low concentration region 103 is first formed. The concentration region 103b may be formed.

  Further, although the wavelength conversion element 103 of the present embodiment is formed of the high impurity concentration region 103a and the low impurity concentration region 103b, there may be three or more regions having different concentrations of the impurity 151.

  Moreover, although the wavelength conversion element 103 of the present embodiment is formed of sapphire, it may be formed of spinel.

<< Embodiment 2 >>
Hereinafter, Embodiment 2 will be described with reference to FIG.

In the light source 200 in the present embodiment, only the composition of the semiconductor layer forming the semiconductor layer 202 and the material of the base material substrate forming the wavelength conversion element 203 are different. That is, the light source 200 includes a stem 101, a semiconductor layer 202 provided on the surface of the stem 101, a wavelength conversion element 203 formed on a part of the surface of the semiconductor layer 202, and a semiconductor as shown in FIG. And two electrodes 104 and 105 provided on the surface of the stem 101 on the side where the layer 202 is not formed. The semiconductor layer 202 includes at least one II-VI group semiconductor compound layer represented by Zn _x Cd _1-x S _y Se _1-y (0 ≦ x ≦ 1, 0 ≦ y ≦ 1), and includes a GaAs substrate (FIG. (Not shown) and electrodes are formed on the front and back sides (not shown). The GaAs substrate is disposed on the surface side of the stem 101. The wavelength conversion element 203 is made of quartz glass, borosilicate glass, or glass containing silicon dioxide as a main component, and is provided by bonding to the surface of the semiconductor layer 202 opposite to the side on which the GaAs substrate is provided. It has been. Only the above two points are different between the first embodiment and the present embodiment, and other points, that is, the composition and function of the components (stem 101, electrodes 104, 105) constituting the light source 200. The manufacturing method of the light source 200 and the mechanism by which the light source 200 emits light are the same as those described in the first embodiment. And the effect which the manufacturing method of the wavelength conversion element 203 of this embodiment, the light source 200, and the light source 200 show | plays is the same as the effect which the manufacturing method of the wavelength conversion element 103 of the said Embodiment 1, the light source 100, and the light source 100 shows.

<< Embodiment 3 >>
Hereinafter, Embodiment 3 will be described with reference to FIGS.

  In this embodiment, the structure of the light source 300, the manufacturing method of the light source 300, and the mechanism by which the light source 300 emits light of a plurality of colors will be described. 6 is a schematic diagram of the light source 300 in the present embodiment, and FIG. 7 is a diagram for explaining a method of manufacturing the light source 300. In FIGS. The same reference numerals as those shown in FIGS.

  Unlike the wavelength conversion element 103 of the light source 100 in the first embodiment, the wavelength conversion element 303 of the light source 300 in the present embodiment can transmit visible light. Other points are the same as those in the first embodiment. Therefore, detailed description of the same parts as those in the first embodiment is omitted.

  As shown in FIG. 6, the light source 300 includes a stem 101, a semiconductor layer 302 provided on the surface of the stem 101, a wavelength conversion element 303 formed on the surface of the semiconductor layer 302, and a semiconductor layer 302. And two electrodes 104 and 105 provided on the surface of the stem 101 on the non-finished side.

The semiconductor layer 302 is a general formula _{B x Ga 1-xyz Al y} In x N (0 ≦ x ≦ 1,0 ≦ y ≦ 1,0 ≦ z ≦ 1) a group III compound semiconductor layer represented by at least one layer In addition, blue light is emitted when a voltage is applied from an external power source via the electrodes 104 and 105.

The wavelength conversion element 303 includes a base material substrate 306 made of sapphire and transmits visible light. In addition, an impurity 151 is included, and a high impurity concentration region 303 a and a low impurity concentration region 303 b are provided in the substrate surface of the base material substrate 306. Specifically, the impurity concentration in the high impurity concentration region 303a is 1 × 10 ¹⁷ cm ⁻² or more and 3 × 10 ¹⁷ cm ⁻² or less, and the impurity concentration in the low impurity concentration region 303b is 1 × 10 ¹⁶ cm ^{−. It is 2} or more and 3 × 10 ¹⁶ cm ⁻² or less. When the blue light emitted from the semiconductor layer 302 is irradiated, the high impurity concentration region 303a emits red light, and the low impurity concentration region 303b emits green light. Here, the substrate surface of the base material substrate 306 is a surface parallel to the interface between the semiconductor layer 302 and the wavelength conversion element 303, as in the substrate surface of the base material substrate 106 in the first embodiment.

  Next, a method for manufacturing the light source 300 will be described.

  First, as shown in FIG. 7A, a sapphire base material substrate 306 to be the wavelength conversion element 303 is prepared, and a mask 161 b is formed on the right half of the surface of the base material substrate 306.

Next, as shown in FIG. 7B, Si ions, which are impurities 151, are mixed into the base material substrate 306 by an ion implantation method. Thereafter, the mask 161b is removed. At this time, the acceleration voltage of the ion implantation is 50 keV or more and 200 keV or less, and the ion implantation amount is 1 × 10 ¹⁷ cm ⁻² or more and 3 × 10 ¹⁷ cm ⁻² or less. Here, when the mask 161b is formed, since the impurity 151 is not mixed into the base material substrate 306 where the mask 161b is formed on the surface, the impurity 151 is included in the portion where the mask 161b is not formed on the surface. As shown in FIG. 7C, a high impurity concentration region 303 a is formed in the left half of the base material substrate 306.

  Subsequently, the mask 161b is removed, and the mask 161a is formed on the surface of the base material on which the mask 161b is not formed in the above two steps, that is, the left half of the base material.

Subsequently, as shown in FIG. 7D, a mask 161a is formed on the surface of the base material substrate 306 where the mask 161b was not formed in the above two steps, that is, on the left half of the base material substrate 306. Then, Si ions 151 which are impurities are mixed into the base material substrate 306 by an ion implantation method. Thereafter, the mask 161a is removed. At this time, the acceleration voltage for ion implantation of Si ions is 50 keV or more and 200 keV or less. The ion implantation amount of Si ions is 1 × 10 ¹⁶ cm ⁻² or more and 3 × 10 ¹⁶ cm ⁻² or less, which is smaller than the ion implantation amount in the above process. Here, when the mask 161a is formed, since the impurity 151 is not mixed into the base material substrate 306 where the mask 161a is formed on the surface, the impurity 151 is the base material substrate where the mask 161b is not formed on the surface. In this step, the impurity low concentration region 303b is formed in the right half of the base material substrate 306.

  Then, thermal annealing is performed in a nitrogen atmosphere at 700 ° C. or higher for 30 minutes on the base material substrate on which the high impurity concentration region 303a and the low impurity concentration region 303b are formed. Accordingly, the wavelength conversion element 303 in which the high impurity concentration region 303a is formed in the right half of the base material substrate 306 shown in FIG. 7E and the low impurity concentration region 303b is formed in the left half can be manufactured.

Further, the surface of the wavelength conversion element 303, the wavelength converting element 303 as a base material _{substrate, B x Ga 1-xyz Al} y In z N (0 ≦ x ≦ 1,0 ≦ y ≦ 1,0 ≦ z ≦ 1, A semiconductor layer 302 is formed by epitaxially growing a semiconductor layer including a semiconductor layer represented by 0 ≦ x + y + z ≦ 1). And the surface which opposes the surface in which the wavelength conversion element 303 is mounted among the surfaces of the semiconductor layer 302, and the surface of the flat cylindrical stem 101 are adhere | attached. As a result, the semiconductor layer 302 is formed on the surface of the stem 101, and the wavelength conversion element 303 is formed on the surface of the semiconductor layer 302.

  Thereafter, electrodes 104 and 105 are provided on the surface of the stem 101 on the side where the semiconductor layer 302 and the wavelength conversion element 303 are not bonded. Thereby, the light source 300 shown in FIG. 6 can be manufactured. As described above, the light source 300 in the present embodiment does not need to adhere the semiconductor layer 302 and the wavelength conversion element 303, and thus can be manufactured more easily than the light source 100 in the first embodiment and the manufacturing yield is high. Get better.

  Next, the mechanism by which the light source 300 emits multicolor light will be described.

  The mechanism for emitting red light and green light is the same as the mechanism for causing the light source 100 in the first embodiment to emit red light and green light. The mechanism for emitting blue light is also the same in the first embodiment and the present embodiment. However, since the wavelength conversion element 303 in this embodiment can transmit visible light, even if the wavelength conversion element 303 is formed on the entire surface of the semiconductor layer 302, blue light is irradiated to the wavelength conversion element 303. As a result, the light source 300 emits white light as shown in FIG.

  The effects exhibited by the wavelength conversion element 303, the light source 300, and the method of manufacturing the light source 300 of the present embodiment are the following effects in addition to the effects exhibited by the wavelength conversion element 103, the light source 100, and the method of manufacturing the light source 100 of the first embodiment. Play. That is, the light source 300 in the present embodiment is manufactured by using the wavelength conversion element 303 as a base material substrate and crystal-growing the semiconductor layer 302 on the surface of the wavelength conversion element 303. Therefore, unlike the light source 100 in the first embodiment, it is not necessary to bond and fix the semiconductor layer 302 and the wavelength conversion element 303 using an adhesive or the like. Therefore, it is possible to easily manufacture as compared with the first embodiment, and the manufacturing yield is improved.

In the present embodiment, the semiconductor layer 302 is a II-VI group semiconductor compound layer represented by Zn _x Cd _1-x S _y Se _1-y (0 ≦ x ≦ 1, 0 ≦ y ≦ 1). At least one layer may be included. The wavelength conversion element 303 may be formed of spinel.

<< Other Embodiments >>
In the light source 100 of the first embodiment, the semiconductor layer 102 is _{B x Ga 1-xyz Al y} In z N (0 ≦ x ≦ 1,0 ≦ y ≦ 1,0 ≦ z ≦ 1,0 ≦ x + y + z ≦ 1) And the wavelength conversion element 103 is made of sapphire. In the light source 200 of the second embodiment, the semiconductor layer 202 is made of Zn _x Cd _{1 -x} S _y Se _{1 -y.} A glass containing at least one II-VI group semiconductor compound layer represented by (0 ≦ x ≦ 1, 0 ≦ y ≦ 1), and the wavelength conversion element 203 having quartz glass, borosilicate glass or silicon dioxide as a main component However, the combination of the composition of the semiconductor layer and the material of the wavelength conversion element is not limited to these. At least a group III compound semiconductor layer on which the semiconductor layer is represented by _{B x Ga 1-xyz Al y} In z N (0 ≦ x ≦ 1,0 ≦ y ≦ 1,0 ≦ z ≦ 1,0 ≦ x + y + z ≦ 1) The wavelength conversion element may be formed of quartz glass, borosilicate glass, or glass mainly composed of silicon dioxide. Conversely, the semiconductor layer may be Zn _x Cd _1-x S _y Se _{1- The} wavelength conversion element may be formed of sapphire or spinel, including at least one II-VI group semiconductor compound layer represented by _y (0 ≦ x ≦ 1, 0 ≦ y ≦ 1).

  The wavelength conversion element of the present invention is particularly useful as a wavelength conversion element used for a white light source or a multicolor light source that mixes two or more colors of light. The light source of the present invention is particularly useful as a white light source or a multicolor light source that mixes two or more colors of light, and the light source manufacturing method is particularly a white light source or a multicolor light source that mixes two or more colors of light. It is useful as a method for producing the above.

1 is a schematic diagram of a light source 100 according to Embodiment 1. FIG. It is explanatory drawing of the manufacturing method of the light source 100 in Embodiment 1. FIG. 3 is an enlarged view of a semiconductor layer 102 and a wavelength conversion element 103 in Embodiment 1. FIG. It is a spectrum figure of the light which the light source 100 in Embodiment 1 emits. It is a schematic diagram of the light source 200 in Embodiment 2. It is a schematic diagram of the light source 300 in the third embodiment. It is explanatory drawing of the manufacturing method of the light source 300 in Embodiment 3. FIG. It is a schematic diagram of full color LED400 in a prior art example.

Explanation of symbols

100, 200, 300 Light source 102, 202, 302 Semiconductor layer 103, 203, 303 Wavelength conversion element 104, 105, 404, 405, 406, 407 Electrode 106, 306 Base substrate 151 Impurity 161a, 161b Mask

Claims (26)

  A wavelength conversion element that is made of a base material substrate containing impurities and emits light having a wavelength different from the wavelength of visible light when irradiated with visible light. In the substrate surface of the base material substrate, comprising a plurality of regions having different impurity concentrations,
The wavelength conversion element according to claim 1, wherein the regions having different impurity concentrations emit light having different wavelengths when irradiated with the visible light.   3. The wavelength conversion element according to claim 1, wherein the base material substrate is made of glass mainly composed of quartz glass, borosilicate glass, or silicon dioxide.   The wavelength conversion element according to claim 1, wherein the base material substrate is formed of sapphire or spinel.   The wavelength conversion element according to claim 1, wherein the impurity is Si.   The wavelength conversion element according to claim 1, wherein the impurity is a particle having a diameter of 1 nm to 10 nm. The base material substrate has a region where the impurity concentration is 1 × 10 ¹⁷ cm ⁻² or more and 3 × 10 ¹⁷ cm ⁻² or less and the impurity concentration is 1 × 10 ¹⁶ within the substrate surface of the base material substrate. The wavelength conversion element according to claim 1, further comprising a region that is not less than cm ^{−2 and not} more than 3 × 10 ¹⁶ cm ⁻² . The visible light is blue light,
The wavelength conversion element according to any one of claims 1 to 7, which emits red and green light when irradiated with the blue light. A semiconductor layer emitting visible light;
A wavelength conversion element provided on a part of the surface of the semiconductor layer;
An electrode for applying a voltage to the semiconductor layer;
A light source comprising:
The semiconductor layer emits the visible light when the voltage is applied through the electrode,
The said wavelength conversion element consists of a base material substrate containing an impurity, and emits light having a wavelength different from that of the visible light when irradiated with the visible light. The wavelength conversion element includes a plurality of regions having different impurity concentrations in the substrate surface of the base material substrate,
The light source according to claim 9, wherein the regions having different impurity concentrations emit light having different wavelengths when irradiated with the visible light.   11. The light source according to claim 9, wherein the base material substrate is made of glass mainly composed of quartz glass, borosilicate glass, or silicon dioxide.   The light source according to claim 9 or 10, wherein the base material substrate is formed of sapphire or spinel.   The light source according to claim 9, wherein the impurity is Si.   The light source according to claim 9, wherein the impurity is a particle having a diameter of 1 nm to 10 nm.   The light source according to claim 9, wherein the semiconductor layer is formed of a group III nitride semiconductor or a group II-VI compound semiconductor. The wavelength conversion element includes a region in which a concentration of the impurity is 1 × 10 ¹⁷ cm ⁻² or more and 3 × 10 ¹⁷ cm ⁻² or less in a plane perpendicular to a direction in which the visible light is irradiated, and the impurity The light source according to claim 9, further comprising a region having a concentration of 1 × 10 ¹⁶ cm ⁻² or more and 3 × 10 ¹⁶ cm ⁻² or less. The visible light is blue light,
The light source according to claim 9, wherein the wavelength conversion element emits red and green light when irradiated with the blue light. Mixing impurities into the base material substrate;
Placing the base material substrate on part of the surface of the semiconductor layer;
Providing an electrode on the surface of the semiconductor layer opposite to the side on which the base material substrate is formed;
Including
The semiconductor layer emits visible light when a voltage is applied through the electrode,
The base material substrate containing the impurity emits light having a wavelength different from the wavelength of the visible light when irradiated with the visible light. Forming a semiconductor layer on the surface of the base material substrate;
Mixing impurities into the base material substrate;
Providing an electrode on the surface of the semiconductor layer opposite to the side on which the base material substrate exists;
Including
The semiconductor layer emits visible light when a voltage is applied through the electrode,
The base material substrate containing the impurity emits light having a wavelength different from the wavelength of the visible light when irradiated with the visible light.   The light source manufacturing method according to claim 18, wherein the step of mixing impurities into the base material substrate is performed by an ion implantation method. The step of mixing impurities into the base material substrate includes a step of forming a region having a predetermined impurity concentration in a part of the substrate surface of the base material substrate;
Forming a region having an impurity concentration different from the impurity concentration in the region having the predetermined impurity concentration in a portion of the substrate surface different from a part of the substrate surface of the base material substrate;
The method of manufacturing a light source according to claim 18, comprising:   The method of manufacturing a light source according to any one of claims 18 to 21, wherein the impurity is Si.   23. The method of manufacturing a light source according to claim 18, wherein the base material substrate is made of glass mainly composed of quartz glass, borosilicate glass, or silicon dioxide.   The method for manufacturing a light source according to any one of claims 18 to 23, wherein the base material substrate is formed of sapphire or spinel.   The method for manufacturing a light source according to any one of claims 18 to 24, wherein the semiconductor layer is formed of a group III semiconductor or a group II-VI semiconductor.   When the visible light is irradiated, the region having the predetermined impurity concentration and the region having the impurity concentration different from the impurity concentration in the region having the predetermined impurity concentration respectively have light having different wavelengths. The method for producing a light source according to claim 21, wherein the light source emits light.

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