TWI405836B - Fluorescence material - Google Patents
Fluorescence material Download PDFInfo
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- TWI405836B TWI405836B TW97137070A TW97137070A TWI405836B TW I405836 B TWI405836 B TW I405836B TW 97137070 A TW97137070 A TW 97137070A TW 97137070 A TW97137070 A TW 97137070A TW I405836 B TWI405836 B TW I405836B
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Abstract
Description
本發明涉及一種適用於LED發光元件的螢光材料，具體的說是，涉及一種螢光材料的結構。The present invention relates to a fluorescent material suitable for use in an LED light-emitting element, and more particularly to a structure of a fluorescent material.
利用發光二極體(Light Emitting Diode，簡稱LED)產生與太陽光色相似的白光，以大幅取代傳統日光燈等白光照明，乃本世紀照明光源科技領域積極研發的目標。目前全球推動單晶片白光LED的封裝技術中多半研究主要為利用發光波長440~460納米的藍光LED晶片，激發黃光螢光粉混合封裝成白光LED。關於螢光粉應用於封裝白光LED的規範並無明確的使用方式。The use of Light Emitting Diode (LED) to produce white light similar to the color of sunlight to replace white light such as traditional fluorescent lamps is an active goal of the field of lighting source technology in this century. At present, most of the global packaging technologies for driving single-chip white LEDs mainly use blue LED chips with emission wavelengths of 440-460 nm to stimulate the yellow fluorescent powder to be packaged into white LEDs. There is no clear way to use the specification of phosphor powder for packaging white LEDs.
又，近來白光封裝之研究引起廣泛地討論與研究，如何增加光之萃取效率為一重要課題，諸如表面粗糙化、光子晶體排列方式、設計不同之封裝結構等，皆已被證實均能有效地提升光的萃取效率。而關於螢光粉層之結構位置，亦越來越受到重視。Moreover, recent research on white light packaging has led to extensive discussion and research. How to increase the extraction efficiency of light is an important issue, such as surface roughening, photonic crystal arrangement, and different packaging structures, all of which have been proven to be effective. Improve the extraction efficiency of light. The structural position of the phosphor powder layer is also receiving more and more attention.
然而，多數的研究均集中於整個LED元件的結構設計，或是關於螢光粉層塗布位置與結構改變的探討，並無針對螢光材料顆粒的研究與探討。However, most of the research has focused on the structural design of the entire LED component, or on the location and structural changes of the phosphor powder coating. There is no research and discussion on the phosphor particle.
事實上，螢光材料顆粒的表面結構、大小等等因素均影響光的萃取效率。有鑒於此，提供一種螢光材料，通過該螢光材料的顆粒的結構增加光的萃取效率確為必要。In fact, the surface structure, size and other factors of the phosphor material particles affect the extraction efficiency of light. In view of the above, there is provided a fluorescent material, and it is necessary to increase the extraction efficiency of light by the structure of the particles of the fluorescent material.
本發明所要解決的技術問題在於提供一種螢光材料，利用該螢光材料顆粒結構，來增加LED光的萃取率。The technical problem to be solved by the present invention is to provide a fluorescent material which utilizes the particle structure of the fluorescent material to increase the extraction rate of the LED light.
為實現上述目的，一種螢光材料，該螢光材料顆粒的結晶區域粒徑為dc ，該結晶區域粒徑dc 的取值範圍為：150nm≧dc ≧10nm。In order to achieve the above object, a fluorescent material having a crystal region particle diameter d c and a crystal region particle diameter d c having a value ranging from 150 nm ≧ d c ≧ 10 nm.
為實現上述目的，一種螢光材料，該螢光材料顆粒的粒徑之長軸與短軸之比為r，該r的取值範圍為：3≧r>1。In order to achieve the above object, a fluorescent material having a ratio of a major axis to a minor axis of the particle diameter of the phosphor material is r, and the value of r ranges from 3 ≧r>1.
為實現上述目的，一種螢光材料顆粒具有幾何形狀的蝕刻層。To achieve the above object, a phosphor material particle has a geometrically etched layer.
優選的是，所述的蝕刻層呈錐形、長方條形、圓形或凹洞形。Preferably, the etched layer has a tapered shape, a rectangular strip shape, a circular shape or a concave shape.
優選的是，所述的螢光粉層的外層塗敷有至少一層包覆介質。Preferably, the outer layer of the phosphor layer is coated with at least one coating medium.
優選的是，該包覆介質外具有膠體。Preferably, the coating medium has a colloid outside.
優選的是，所述螢光材料的折射率≧包覆介質的折射率≧膠體的折射率。Preferably, the refractive index of the fluorescent material ≧ the refractive index of the coating medium ≧ colloidal refractive index.
優選的是，該至少一層包覆介質的折射率，由表及裏為n1 、n2 …nn ，折射率範圍為：螢光材料的折射率≧n1 ≧n2 …≧nn ≧膠體的折射率。Preferably, the refractive index of the at least one cladding medium is n 1 , n 2 ... n n from the surface and the inside, and the refractive index ranges from: refractive index ≧n 1 ≧n 2 ... ≧n n萤 of the fluorescent material The refractive index of the colloid.
作為LED封裝的螢光材料，採用上述結構利於提供光線的萃取率。As the fluorescent material of the LED package, the above structure is used to provide an extraction rate of light.
以下結合附圖對本發明作進一步詳細的說明：The present invention will be further described in detail below with reference to the accompanying drawings:
有關本發明之前述及其它技術內容、特點與功效，在以下配合參考附圖的較佳實施例的詳細說明中，將可清楚呈現。The above and other technical contents, features and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments of the invention.
在本發明被詳細描述之前，要注意的是，在以下的說明內容中，類似的元件是以相同的編號來表示。Before the present invention is described in detail, it is noted that in the following description, similar elements are denoted by the same reference numerals.
3a~3b圖所示為LED的封裝結構。請參閱3a圖，LED10包括有一發光晶片1、一反射層2、封裝膠體3以及一螢光粉層4。這其中，該發光晶片1為Ⅲ-V族半導體所形成的多元晶片，而反射 層2可將螢光粉層4反射的光再反射回去，並亦可增加粗糙化，增加反射角度，避免全反射發生，以提升光的萃取效率。該螢光粉層4亦即為本發明的螢光材料，是充滿螢光材料顆粒5。請參閱圖3b，為另一種封裝結構，該螢光粉層4為一弧形結構。螢光粉層4為由內層模與外層模所形成一厚度可調的螢光粉層，將螢光材料塗布於球殼上。3a~3b shows the package structure of the LED. Referring to FIG. 3a, the LED 10 includes an illuminating chip 1, a reflective layer 2, an encapsulant 3, and a phosphor layer 4. Among them, the illuminating wafer 1 is a multi-element formed by a III-V semiconductor, and the reflection Layer 2 can reflect the light reflected by the phosphor layer 4 back, and can also increase the roughness, increase the angle of reflection, and avoid the occurrence of total reflection to enhance the extraction efficiency of light. The phosphor layer 4, which is the fluorescent material of the present invention, is filled with the phosphor material particles 5. Referring to FIG. 3b, in another package structure, the phosphor layer 4 is an arc structure. The phosphor layer 4 is formed by an inner layer mold and an outer layer mold, and a phosphor powder layer is formed on the spherical shell.
該發光晶片1可激發出藍光(420-460nm)或是紫外光(350-410nm)，使得該螢光粉層4受該藍光激發出黃光，並與該藍光或紫外光最終混為白光發出。The luminescent wafer 1 can excite blue light (420-460 nm) or ultraviolet light (350-410 nm), so that the fluorescent powder layer 4 is excited by the blue light to emit yellow light, and finally mixed with the blue light or ultraviolet light to emit white light. .
本發明的螢光材料是具有多個螢光材料顆粒，螢光材料顆粒如圖1以及圖2a~2d所示。螢光材料顆粒5的外層部分61亦是顆粒大小的徑長，且其內部有結晶區域(crystallite size)62。從Ⅲ-V族半導體晶片中所發出之入射光70包括藍光(420~460nm)或是紫外光(350~410nm)，而入射光70在該結晶區域62中經能量轉換後發出出射光72。The phosphor material of the present invention has a plurality of particles of phosphor material as shown in Figures 1 and 2a-2d. The outer layer portion 61 of the phosphor material particles 5 is also a particle-sized diameter and has a crystallite size 62 inside. The incident light 70 emitted from the III-V semiconductor wafer includes blue light (420-460 nm) or ultraviolet light (350-410 nm), and the incident light 70 is subjected to energy conversion in the crystalline region 62 to emit the outgoing light 72.
圖5a以及圖5b所示的樣品的粒徑分別為大小為6.55μm、12.89μm。通過謝樂等式(Scherrer Equation)可計算出結晶粒徑，如下公式：
在該等式中d為預計算的結晶粒徑，λ為入射X光之波長，於此為1.5405981Å，B為繞射強度之半高寬(FWHM)，θB 為所計算的繞射角角度。In this equation d is the pre-calculated crystal grain size, λ is the wavelength of the incident X-ray, here is 1.5405981Å, B is the half-height width (FWHM) of the diffraction intensity, and θ B is the calculated diffraction angle angle.
通過該謝樂等式(Scherrer Equation)可以算出5a圖的樣品的螢光材料顆粒結晶粒徑大小dc 約為100nm；5b圖的樣品螢光材料顆粒5的結晶粒徑大小為92nm。於此可得知，雖兩樣品之粒徑相差近一倍，但結晶粒徑相當接近，由此可證明當粒徑大於某一數值之後，其結晶粒徑並不會隨之改變，而趨於一穩定值。於計算時，結晶粒徑取決於繞射角與半高寬的寬度，亦即相同的繞射角之半高寬越窄計算出的結果結晶粒徑大。一般而言，結晶粒徑越大發光強度越強，但也不是越強越好，當粒徑大到某個程度之後，反而會有光被散射掉而造成光強度變弱。總之，綜合以上資料計算，最佳的結晶區域粒徑範圍為：150nm≧dc ≧10nm。The crystal material particle size d c of the sample of the 5a graph can be calculated by the Scherrer equation to be about 100 nm; the crystal grain size of the sample phosphor material particles 5 of the 5b graph is 92 nm. It can be seen that although the particle diameters of the two samples are nearly doubled, the crystal grain size is quite close, which proves that when the particle diameter is larger than a certain value, the crystal grain size does not change, and At a stable value. In the calculation, the crystal grain size depends on the diffraction angle and the width of the full width at half maximum, that is, the narrower the width and width of the same diffraction angle, the calculated crystal grain size is large. In general, the larger the crystal grain size, the stronger the light intensity, but the stronger the better, when the particle size is large to some extent, the light is scattered and the light intensity is weakened. In summary, based on the above data, the optimal crystal size range is: 150 nm ≧d c ≧ 10 nm.
請參閱圖5c，圖5c顯示出此兩不同粒徑之樣品。此兩樣品皆發光波長由460nm的藍光LED晶片當作激發源，再收其放射光譜，其最大放射波長皆為544nm。依據量測結果顯示，此兩樣品所量測出之結果相同，亦是其發光強度並不隨著粒徑改變而有增 強或減弱之現象，反而與結晶粒徑之資料而有一致性。Please refer to Figure 5c, which shows the samples of the two different particle sizes. Both of the samples have an emission wavelength of 460 nm blue LED chip as an excitation source, and then receive the emission spectrum, and the maximum emission wavelength is 544 nm. According to the measurement results, the results measured by the two samples are the same, and the luminescence intensity does not increase with the change of the particle size. The phenomenon of strong or weakening is consistent with the data of crystal grain size.
YAG螢光粉之折射率經量測約為1.8，而所使用的封裝膠體折射率隨使用的封裝膠體不同而有所不同，以矽(silicon)為例約為1.5，因而光從外界要進入螢光粉，從光疏到光密不會產生全反射，但當入射光70經過能量轉換經發射出螢光粉時，則遭遇到光密到光疏的問題，此一結果會造成全反射。於是，本專利於螢光材料顆粒5的表面做粗糙化，或於粉體表面做不同的結構，以降低全反射現象，進而增加光導出的機率。The refractive index of YAG phosphor is measured to be about 1.8, and the refractive index of the encapsulant used varies depending on the encapsulant used. For example, silicon is about 1.5, so light enters from the outside. Fluorescent powder, from light to light, does not produce total reflection, but when the incident light 70 undergoes energy conversion and emits fluorescent powder, it encounters the problem of light to light, which results in total reflection. . Therefore, this patent roughens the surface of the phosphor material particles 5, or makes a different structure on the surface of the powder to reduce the total reflection phenomenon, thereby increasing the probability of light emission.
請參閱圖2a~圖2d，如圖2a所示，螢光粉表面設計成三角椎狀63，如圖2b所示，螢光粉表面設計成長方條狀64；請參閱圖2c所示，螢光粉表面設計成圓球狀65；請參閱圖2d所示，螢光粉表面還可以被設計成凹洞狀66，將減少光射出粉體時全反射的可能。於此所稱之減少全反射之可能即是先前提到之粗糙化或是置入光子晶體的結構，而大幅增加光導出的機率。Referring to FIG. 2a to FIG. 2d, as shown in FIG. 2a, the surface of the phosphor powder is designed as a triangular pyramid 63, as shown in FIG. 2b, and the surface of the phosphor powder is designed to grow into a strip shape 64; see FIG. 2c, The surface of the powder is designed to be spherical 65; as shown in Figure 2d, the surface of the phosphor can also be designed to have a concave shape 66, which will reduce the possibility of total reflection when the light is emitted. What is referred to herein as reducing total reflection is the previously mentioned roughening or placement of photonic crystal structures, which greatly increases the probability of light export.
另外，本發明中於螢光粉粉體外層塗布一層或是多層不同折射率的包覆介質61，此一層或多層包覆介質61的折射率n介於螢光粉5與封裝膠體3之間，以上述YAG螢光粉與封裝膠體矽(Silicon)為例，其限制範圍為1.8≧n≧1.5。相同例子於多層塗布則1.8≧n1 ≧n2 …≧nn ≧1.5，其中n1 、n2 …nn 分層為從螢光粉至封裝 膠體3依序分佈。In addition, in the present invention, one or more layers of coating medium 61 having different refractive indexes are coated on the outer layer of the phosphor powder, and the refractive index n of the one or more layers of the coating medium 61 is between the phosphor powder 5 and the encapsulant 3 For example, the above YAG phosphor powder and the encapsulant colloid (Silicon) have a limitation range of 1.8≧n≧1.5. The same example is applied in a multilayer coating of 1.8≧n 1 ≧n 2 ... ≧n n ≧1.5, wherein n 1 , n 2 ... n n are layered in order from the phosphor powder to the encapsulant 3 in order.
請參閱圖4之所示，73為螢光材料顆粒不為圓之粒徑短軸部分；71螢光材料顆粒不為圓的粒徑長軸。於此先定義長軸71除以短軸73得一比值r。若光自螢光材料顆粒內部62發射出來，較佳的發光效率的螢光粉的顆粒粒徑約為圓形，但因某些合成方式未能使粉末顆粒形成圓形，反倒是形成啞鈴短柱狀之形貌，當螢光材料顆粒5的外層部分61之顆粒形貌以3≧r≧1為最佳，亦是當螢光材料顆粒5粒徑之長軸與短軸比介於1~3之間，其發光效率為最佳。Referring to FIG. 4, 73 is a short-axis portion of the particle diameter of the fluorescent material particles; 71 is not the long axis of the particle diameter of the circle. Here, a ratio r is defined by dividing the long axis 71 by the short axis 73. If the light is emitted from the interior 62 of the phosphor material, the particle size of the phosphor of the preferred luminous efficiency is about a circular shape, but due to some synthetic methods, the powder particles are not formed into a circular shape, but a dumbbell is formed shortly. The shape of the columnar shape, when the particle shape of the outer layer portion 61 of the phosphor material particles 5 is preferably 3≧r≧1, and the ratio of the major axis to the minor axis of the particle size of the phosphor material 5 is 1 Between ~3, its luminous efficiency is the best.
以上所述，僅為本發明之較佳實施例而已，當不能以此限定本發明實施之範圍，即大凡依本發明權利要求及發明說明書所記載的內容所作出簡單的等效變化與修飾，皆仍屬本發明權利要求所涵蓋範圍之內。此外，摘要部分和標題僅是用來輔助專利文獻搜尋之用，並非用來限制本發明之權利範圍。The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, that is, the simple equivalent changes and modifications made by the contents of the present invention and the description of the invention are All are still within the scope of the claims of the present invention. In addition, the abstract sections and headings are only used to assist in the search of patent documents and are not intended to limit the scope of the invention.
1‧‧‧發光晶片1‧‧‧Lighting chip
2‧‧‧反射層2‧‧‧reflective layer
3‧‧‧封裝膠體3‧‧‧Package colloid
4‧‧‧螢光粉層4‧‧‧Fluorescent powder layer
5‧‧‧螢光材料顆粒5‧‧‧Fluorescent material particles
61‧‧‧外層部分61‧‧‧ outer part
62‧‧‧螢光材料顆粒內62‧‧‧Fluorescent material particles
63‧‧‧三角椎狀63‧‧‧Triangular
64‧‧‧長方條狀64‧‧‧Rectangle strips
65‧‧‧圓球狀65‧‧‧Spherical
70‧‧‧入射光70‧‧‧ incident light
71‧‧‧長軸71‧‧‧ long axis
72‧‧‧出射光72‧‧‧Out of light
73‧‧‧短軸73‧‧‧Short axis
10‧‧‧LED10‧‧‧LED
第1圖為本發明的結構圖。Fig. 1 is a structural view of the present invention.
第2a圖為本發明的螢光材料顆粒表面為三角錐形狀的結構圖。Fig. 2a is a structural view showing the surface of the phosphor material particles of the present invention in the shape of a triangular pyramid.
第2b圖為本發明的螢光材料顆粒表面為條狀的結構圖。Fig. 2b is a structural view showing the surface of the phosphor material particles of the present invention in a strip shape.
第2c圖為本發明的螢光材料顆粒表面為球狀的結構圖。Fig. 2c is a structural view showing the surface of the phosphor particles of the present invention being spherical.
第2d圖為本發明的螢光材料顆粒表面為凹形的結構圖。Fig. 2d is a structural view showing the surface of the phosphor material particles of the present invention being concave.
第3a圖為LED的結構圖，該圖省略金屬引腳架。Figure 3a is a block diagram of the LED, which omits the metal leadframe.
第3b圖為LED的另一種結構圖，該圖省略金屬引腳架。Figure 3b is another block diagram of the LED, which omits the metal leadframe.
第4圖為本發明螢光材料顆粒的長短軸的示意圖。Figure 4 is a schematic illustration of the long and short axes of the phosphor material particles of the present invention.
第5a圖是樣品為YAG螢光粉粒徑大小為6.55μm的X-ray繞射圖譜。Figure 5a is an X-ray diffraction pattern of the sample having a YAG phosphor particle size of 6.55 μm.
第5b圖為是樣品為YAG螢光粉粒徑大小為12.89μm的X-ray繞射圖譜。Figure 5b shows an X-ray diffraction pattern with a YAG phosphor powder particle size of 12.89 μm.
第5c圖為該兩樣品的光激發光譜圖，包含激發圖譜與放射圖譜，圖中YAG(A)為YAG螢光粉粒徑大小為6.55μm的樣品，YAG(B)為螢光粉粒徑大小為12.89μm的樣品。Figure 5c is a photoexcitation spectrum of the two samples, including the excitation spectrum and the radiation spectrum. In the figure, YAG(A) is a sample with a YAG phosphor particle size of 6.55 μm, and YAG(B) is a phosphor particle size. A sample having a size of 12.89 μm.
5‧‧‧螢光材料顆粒5‧‧‧Fluorescent material particles
61‧‧‧外層部分61‧‧‧ outer part
62‧‧‧螢光材料顆粒內62‧‧‧Fluorescent material particles
63‧‧‧三角椎狀63‧‧‧Triangular
Claims (7)
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| TW97137070A TWI405836B (en) | 2008-09-26 | 2008-09-26 | Fluorescence material |
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| TW97137070A TWI405836B (en) | 2008-09-26 | 2008-09-26 | Fluorescence material |
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| Publication Number | Publication Date |
|---|---|
| TW201012895A TW201012895A (en) | 2010-04-01 |
| TWI405836B true TWI405836B (en) | 2013-08-21 |
Family
ID=44829133
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| TW97137070A TWI405836B (en) | 2008-09-26 | 2008-09-26 | Fluorescence material |
Country Status (1)
| Country | Link |
|---|---|
| TW (1) | TWI405836B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6100633A (en) * | 1996-09-30 | 2000-08-08 | Kabushiki Kaisha Toshiba | Plasma display panel with phosphor microspheres |
| US6781308B2 (en) * | 2001-01-10 | 2004-08-24 | Nec Corporation | Plasma display panel having a fluorescent layer made of mono-crystal particles |
| US20050230356A1 (en) * | 2002-04-02 | 2005-10-20 | Nanosys, Inc. | Methods of making, positioning and orienting nanostructures, nanostructure arrays and nanostructure devices |
| US20050275346A1 (en) * | 2000-08-23 | 2005-12-15 | Idemitsu Kosan Co., Ltd. | Organic EL display device |
| US20060158089A1 (en) * | 2004-09-14 | 2006-07-20 | Sharp Kabushiki Kaisha | Fluorescent material and light-emitting apparatus employing the same |
-
2008
- 2008-09-26 TW TW97137070A patent/TWI405836B/en active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6100633A (en) * | 1996-09-30 | 2000-08-08 | Kabushiki Kaisha Toshiba | Plasma display panel with phosphor microspheres |
| US20050275346A1 (en) * | 2000-08-23 | 2005-12-15 | Idemitsu Kosan Co., Ltd. | Organic EL display device |
| US6781308B2 (en) * | 2001-01-10 | 2004-08-24 | Nec Corporation | Plasma display panel having a fluorescent layer made of mono-crystal particles |
| US20050230356A1 (en) * | 2002-04-02 | 2005-10-20 | Nanosys, Inc. | Methods of making, positioning and orienting nanostructures, nanostructure arrays and nanostructure devices |
| US20060158089A1 (en) * | 2004-09-14 | 2006-07-20 | Sharp Kabushiki Kaisha | Fluorescent material and light-emitting apparatus employing the same |
Also Published As
| Publication number | Publication date |
|---|---|
| TW201012895A (en) | 2010-04-01 |
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