TWI532823B - Green-emitting, garnet-based phosphors in general and backlighting applications - Google Patents

Description

一般以石榴石為主之綠光磷光體及背光應用 Garnet-based green phosphor and backlight application

本發明之實施例概言之係關於以石榴石為主之綠光磷光體，其適於多個不同技術領域，尤其背光應用。具體而言，本發明係關於以鎦為主之石榴石。 SUMMARY OF THE INVENTION Embodiments of the present invention generally relate to garnet-based green phosphors that are suitable for a variety of different technical fields, particularly backlighting applications. Specifically, the present invention relates to garnets which are mainly enamel.

本發明之實施例係關於摻雜鈰之以石榴石為主之磷光體。YAG：Ce係該磷光體之實例，且此化合物已用於自所謂「白光LED」產生白光之商業市場達一段時間。術語「白光LED」係誤稱，此乃因發光二極體發射具體單色光而非由人眼視為白色之波長的組合，但該術語仍然盤踞在照明工業之詞彙中。 Embodiments of the invention relate to garnet-based phosphors doped with antimony. YAG: Ce is an example of this phosphor, and this compound has been used in commercial markets for the production of white light from so-called "white LEDs" for some time. The term "white LED" is a misnomer, which is a combination of wavelengths emitted by a light-emitting diode that emits a specific monochromatic light rather than being perceived by the human eye as white, but the term is still in the vocabulary of the lighting industry.

與其他磷光體主體、尤其彼等以矽酸鹽、硫酸鹽、次氮基矽酸鹽及側氧基-次氮基矽酸鹽為主者相比，YAG：Ce在由藍光激發時具有相對較高吸收效率，在高溫度及濕度環境中穩定，且具有高量子效率(QE>95%)，所有白色均展示寬發射光譜。 YAG:Ce has a relative excitation of blue light compared to other phosphor bodies, especially those based on citrate, sulphate, nitrilo ruthenate and pendant oxy-nitrilo ruthenate. Higher absorption efficiency, stable in high temperature and humidity environments, and high quantum efficiency (QE > 95%), all whites exhibit a broad emission spectrum.

若在使用YAG：Ce磷光體時具有缺點，且在某些應用中具有缺點，則該缺點係此磷光體之峰發射對於在(例如)背光應用中用作發光源而言太長(換言之，紅色太深)。 If there are disadvantages when using YAG:Ce phosphors, and there are disadvantages in some applications, the disadvantage is that the peak emission of this phosphor is too long for use as a source of illumination in, for example, backlight applications (in other words, Red is too deep).

YAG：Ce之替代方案係摻雜鈰之Lu₃Al₅O₁₂化合物(LAG：Ce)，其具有與YAG：Ce相同之結晶結構，具有與以釔為主之化合物類似的溫度 及濕度穩定性，且量子效率亦如此。儘管具有該等類似性，但LAG：Ce呈現與其YAG對等部分不同之峰發射波長；在鎦情形下，此峰波長係在約540nm下。然而，此發射波長對於用於背光應用中而言仍不夠短。 An alternative to YAG:Ce is a Lu ₃ Al ₅ O ₁₂ compound (LAG:Ce) doped with yttrium, which has the same crystal structure as YAG:Ce, and has similar temperature and humidity stability to ruthenium-based compounds. And the quantum efficiency is also the same. Despite these similarities, LAG:Ce exhibits a different peak emission wavelength than its YAG counterpart; in the case of erbium, this peak wavelength is at about 540 nm. However, this emission wavelength is still not short enough for use in backlighting applications.

因此，業內、尤其與背光技術有光之領域中所需者係具有石榴石結構及比YAG：Ce或LAG：Ce之峰發射波長短之峰發射波長的磷光體。 Therefore, the industry, especially in the field of light with backlight technology, has a garnet structure and a phosphor having a peak emission wavelength shorter than the peak emission wavelength of YAG:Ce or LAG:Ce.

本發明之實施例係關於以石榴石為主之綠光磷光體，其具有通式(Lu_1-a-b-cY_aTb_bA_c)₃(Al_1-dB_d)₅(O_1-eC_e)₁₂：Ce,Eu，其中A選自由Mg、Sr、Ca及Ba組成之群；B選自由Ga及In組成之群；C選自由F、Cl及Br組成之群；0a1；0b1；0<c0.5；0d1且0<e0.2。單獨或組合使用之「A」元素可為鹼土金屬元素Mg、Sr、Ca及Ba中之任一者，其極有效地使波長移位至較短值。該等化合物在本發明中可稱作「以鹵化LAG為主」之石榴石。 Embodiments of the present invention relate to a garnet-based green phosphor having the general formula (Lu _1-abc Y _a Tb _b A _c ) ₃ (Al _1-d B _d ) ₅ (O _1-e C _e ) ₁₂ : Ce, Eu, wherein A is selected from the group consisting of Mg, Sr, Ca and Ba; B is selected from the group consisting of Ga and In; C is selected from the group consisting of F, Cl and Br; a 1;0 b 1;0<c 0.5;0 d 1 and 0<e 0.2. The "A" element used singly or in combination may be any of the alkaline earth metal elements Mg, Sr, Ca, and Ba, which are extremely effective in shifting the wavelength to a shorter value. These compounds may be referred to as "garbage-based LAG" garnets in the present invention.

在替代實施例中，本發明之綠色石榴石可由式(Y,Lu,A)_x(Al)₅(O,F,Cl)_12+(3/2)x表示；限制條件為x不等於3，且在約2.5至約3.5之範圍內。如在此節中所述之第一式中，A選自由Mg、Sr、Ca及Ba組成之群，且相對於釔及鎦之總量，化學計量含量在大於0至約0.5之範圍內。釔及鎦彼此可互換。該等化合物在本發明中可統稱為基於YAG及LAG之「非整數化學計量化合物」。 In an alternative embodiment, the green garnet of the present invention may be represented by the formula (Y, Lu, A) _x (Al) ₅ (O, F, Cl) _{12+ (3/2) x} ; the constraint is that x is not equal to 3 And in the range of from about 2.5 to about 3.5. As in the first formula described in this section, A is selected from the group consisting of Mg, Sr, Ca, and Ba, and the stoichiometric content is in the range of more than 0 to about 0.5 with respect to the total amount of lanthanum and cerium.钇 and 镏 are interchangeable with each other. These compounds are collectively referred to herein as "non-integer stoichiometric compounds" based on YAG and LAG.

在替代實施例中，本發明之以石榴石為主之綠光磷光體可由式(Y,A)₃(Al,B)₅(O,C)₁₂：Ce³⁺闡述，其中A係Tb、Gd、Sm、La、Lu、Sr、Ca及Mg中之至少一者，包括彼等元素之組合，其中彼等元素對Y之取代量以化學計量方式在約0.1%至約100%範圍內。B係Si、Ge、B、P及Ga中之至少一者，包括其組合，且該等元素以在約0.1至約100化 學計量百分比範圍內之量取代Al。C係F、Cl、N及S中之至少一者，包括其組合，以在約0.1至約100化學計量百分比範圍內之量取代氧。 In an alternative embodiment, the garnet-based green phosphor of the present invention can be illustrated by the formula (Y, A) ₃ (Al, B) ₅ (O, C) ₁₂ : Ce ³⁺ , wherein the A is Tb, At least one of Gd, Sm, La, Lu, Sr, Ca, and Mg, including combinations of elements thereof, wherein the amount of substitution of these elements for Y is stoichiometrically in the range of from about 0.1% to about 100%. At least one of B-type Si, Ge, B, P, and Ga, including combinations thereof, and the elements replace Al with an amount ranging from about 0.1 to about 100 stoichiometric percent. At least one of the C systems F, Cl, N, and S, including combinations thereof, replaces oxygen in an amount ranging from about 0.1 to about 100 stoichiometric percent.

在替代實施例中，本發明之以石榴石為主之綠光磷光體可由式(Y_1-xBa_x)₃Al₅(O_1-yC_y)₁₂：Ce³⁺闡述，其中x及y各自在約0.001至約0.2之範圍內。在此實施例之變化形式中，以石榴石為主之磷光體可由式(Y_1-xBa_x)_zAl₅(O_1-yC_y)_12+(3/2)z：Ce³⁺表示，其中在此實施例中z不等於3，且在約2.5至約3.5之範圍內。在該等實施例中，當構成元素係釔、鋇、鋁、氧及氟時。 In an alternative embodiment, the garnet-based green phosphor of the present invention can be illustrated by the formula (Y _1-x Ba _x ) ₃ Al ₅ (O _1-y C _y ) ₁₂ :Ce ³⁺ , wherein x and y are each in the range of from about 0.001 to about 0.2. In a variation of this embodiment, the garnet-based phosphor may be of the formula (Y _1-x Ba _x ) _z Al ₅ (O _1-y C _y ) _12+(3/2)z :Ce ³⁺ It is indicated that z is not equal to 3 in this embodiment and is in the range of from about 2.5 to about 3.5. In these embodiments, when the constituent elements are lanthanum, cerium, aluminum, oxygen, and fluorine.

本發明之以石榴石為主之綠光磷光體可由雷射或LED(或任一其他該方式)發射之藍光激發，且與黃光-綠光矽酸鹽磷光體及/或以氮化物為主之紅光磷光體中之一者(或二者)組合使用。紅色氮化物具有通式(Ca,Sr)AlSiN₃：Eu²⁺，其進一步包含可選鹵素，且其中紅色氮化物磷光體中之氧雜質含量可小於等於約2重量%。 The garnet-based green phosphor of the present invention may be excited by a laser or a blue light emitted by an LED (or any other means), and with a yellow-green phosphoric acid phosphor and/or a nitride One of the main red phosphors (or both) is used in combination. The red nitride has the general formula (Ca,Sr)AlSiN ₃ :Eu ²⁺ , which further contains an optional halogen, and wherein the content of oxygen impurities in the red nitride phosphor may be less than or equal to about 2% by weight.

圖1顯示具有不同MgF₂添加劑濃度之Lu_2.91Ce_0.09Al₅O₁₂的SEM形貌，其闡釋隨著MgF₂添加劑之量增大，粒徑變大且更均勻；圖2係一系列具有不同MgF₂添加劑濃度之例示性Y_2.91Ce_0.09Al₅O₁₂磷光體的x射線繞射(XRD)圖案；圖3係一系列具有不同MgF₂添加劑濃度之例示性Lu_2.91Ce_0.09Al₅O₁₂磷光體的x射線繞射(XRD)圖案；圖4係一系列具有5wt% MgF₂添加劑及5wt% SrF₂添加劑之例示性Lu_2.91Ce_0.09Al₅O₁₂磷光體的x射線繞射(XRD)圖案；圖5係一系列具有不同MgF₂添加劑含量之例示性Y_2.91Ce_0.09Al₅O₁₂磷光體之發射光譜，該發射光譜係藉由用藍色LED激發磷光體獲得；圖6係在藍色LED激發下一系列具有不同MgF₂添加劑濃度之例示性Y_2.91Ce_0.09Al₅O₁₂磷光體的正規化發射光譜； 圖7係在藍色LED激發下具有不同MgF₂添加劑之Lu_2.91Ce_0.09Al₅O₁₂磷光體的發射光譜；圖8係在藍色LED激發下具有不同MgF₂添加劑之Lu_2.91Ce_0.09Al₅O₁₂磷光體的正規化發射光譜；結果顯示利用特定量之MgF₂添加劑，Lu_2.91Ce_0.09Al₅O₁₂之發射峰移位至短波長，且MgF₂添加劑之量越大，則發射峰波長越短；圖9係具有5wt% MgF₂及5wt% SrF₂添加劑之Lu_2.91Ce_0.09Al₅O₁₂磷光體的正規化發射光譜；將結果與不含作為添加劑之鹵化鹽的對照試樣進行比較；結果闡釋在MgF₂合成化合物下比在SrF₂合成化合物下發射峰移位至更短波長；圖10顯示隨著SrF₂添加劑濃度增大，一系列例示性Lu_2.91Ce_0.09Al₅O₁₂磷光體之發射波長如何減小；圖11係一系列具有不同MgF₂添加劑濃度之例示性Lu_2.91Ce_0.09Al₅O₁₂磷光體的正規化激發光譜，其顯示在MgF₂添加劑濃度增大時，激發光譜變更窄；圖12顯示具有5wt% MgF₂添加劑之例示性Lu_2.91Ce_0.09Al₅O₁₂磷光體的溫度依賴性；且圖13顯示包括例示性以石榴石為主之綠光磷光體之白色LED的光譜，該綠光磷光體具有式Lu_2.91Ce_0.09Al₅O₁₂及5wt% SrF₂添加劑；該白色LED亦包括具有式(Ca_0.2Sr_0.8)AlSiN₃：Eu²⁺之紅色磷光體，且在用發射藍光之InGaN LED激發綠色及紅色磷光體二者時，所得白光具有色彩性質CIE x=0.24及CIE y=0.20；圖14係具有以下組份之白色LED之光譜：藍色InGaN LED、具有3wt%或5wt%添加劑且具有式Lu_2.91Ce_0.09Al₅O₁₂之綠色石榴石、具有式(Ca_0.2Sr_0.8)AlSiN₃：Eu²⁺之紅色氮化物或具有式(Sr_0.5Ba_0.5)₂SiO₄：Eu²⁺之矽酸鹽，其中白光具有色彩座標CIE(x=0.3,y=0.3)；且 圖15係圖14之白色LED系統之光譜，在此情況下在3,000K下量測。 Figure 1 shows the SEM morphology of Lu _2.91 Ce _0.09 Al ₅ O ₁₂ with different MgF ₂ additive concentrations, which illustrates that as the amount of MgF ₂ additive increases, the particle size becomes larger and more uniform; Figure 2 is a series of different exemplary MgF ₂ concentration of the additive of the Y _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor x-ray diffraction (XRD) pattern; FIG. 3 based series of cases with different MgF ₂ additive concentrations of the exemplary Lu _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor X-ray diffraction (XRD) pattern of the body; Figure 4 is an x-ray diffraction (XRD) pattern of an exemplary Lu _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor with 5 wt% MgF ₂ additive and 5 wt% SrF ₂ additive. Figure 5 is a series of emission spectra of an exemplary Y _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor with different MgF ₂ additive contents obtained by exciting the phosphor with a blue LED; Figure 6 is in blue LEDs excite a series of normalized emission spectra of an exemplary Y _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor with different MgF ₂ additive concentrations; Figure 7 is Lu _2.91 Ce _0.09 Al with different MgF ₂ additives under blue LED excitation emission spectrum of the phosphor ₅ O _12; FIG. 8 has a blue LED based excitation MgF ₂ with normalization of additives Lu _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor emission spectrum; results are shown with a specific amount of additives MgF _2, Lu _2.91 Ce _0.09 Al ₅ O ₁₂ of the emission peaks shifted to shorter wavelength, and MgF ₂ The larger the amount of the additive, the shorter the emission peak wavelength; FIG. 9 is the normalized emission spectrum of the Lu _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor having 5 wt% MgF ₂ and 5 wt% SrF ₂ additive; A comparison was made as a control sample of the halide salt of the additive; the results illustrate that the emission peak is shifted to a shorter wavelength under the MgF ₂ synthesis compound than the SrF ₂ synthesis compound; Figure 10 shows a series of SrF ₂ additive concentrations as the SrF ₂ additive concentration increases. How the emission wavelength of the exemplary Lu _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor is reduced; FIG. 11 is a series of normalized excitation spectra of an exemplary Lu _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor having different MgF ₂ additive concentrations, It is shown that the excitation spectrum changes narrowly when the MgF ₂ additive concentration is increased; FIG. 12 shows the temperature dependence of an exemplary Lu _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor having a 5 wt% MgF ₂ additive; and FIG. 13 is shown to include illustrative Garnet White LED spectrum of the green phosphor, the green phosphor has the formula Lu _2.91 Ce _0.09 Al ₅ O ₁₂ and additive 5wt% SrF _2; also includes the white LED having the formula _{(Ca 0.2 Sr 0.8) AlSiN 3} : Eu 2 ⁺ red phosphor, and when both green and red phosphors are excited by blue-emitting InGaN LED, the resulting white light has color properties CIE x = 0.24 and CIE y = 0.20; Figure 14 is a white LED with the following components Spectra: blue InGaN LED, green garnet with 3 wt% or 5 wt% additive and having the formula Lu _2.91 Ce _0.09 Al ₅ O ₁₂ , red nitride having the formula (Ca _0.2 Sr _0.8 )AlSiN ₃ :Eu ²⁺ or having a bismuth _{silicate of the} formula (Sr _0.5 Ba _0.5 ) ₂ SiO ₄ :Eu ²⁺ , wherein white light has a color coordinate CIE (x=0.3, y=0.3); and FIG. 15 is a spectrum of the white LED system of FIG. 14 In the case, measure at 3,000K.

經稀土鈰激活之釔鋁石榴石化合物(YAG：Ce)係磷光體材料之最佳選擇中之一者，若期望應用係高功率LED照明、或非特定的一般性質之冷白色照明，則可製作YAG：Ce。正如人們所預期，在LED晶片供應藍光及激發輻射之情形下且在磷光體與該晶片結合使用、由該晶片激發、與該晶片結合使用、並供應所得產物光之典型黃色/綠色成份之情形下，在一般照明中需要高度有效組份。 One of the best choices for yttrium aluminum garnet compound (YAG:Ce) phosphor materials activated by rare earth lanthanum, if high-power LED illumination or non-specific general-purpose cold white illumination is desired Make YAG:Ce. As is expected, in the case where the LED wafer is supplied with blue light and excitation radiation and the phosphor is used in conjunction with the wafer, excited by the wafer, used in conjunction with the wafer, and supplied with typical yellow/green components of the resulting product light. Underneath, a highly effective component is required in general lighting.

如本揭示內容之前一節中所論述，YAG：Ce證實具有此期望高效率，具有大於約95%之量子效率，且因此，對此數進行改良似乎係艱巨的任務。但業內已知LED晶片之效率隨著發射波長之減小而增大，且因此，無論如何在理論上看起來，若與在較短波長下發射之LED晶片配對之磷光體可由彼等較短波長激發，則將增強一般照明系統之效率。不幸地，伴隨此策略之問題係，當YAG：Ce磷光體之藍色激發輻射之波長降至低於約460nm之程度時，其發射效率會減小。 As discussed in the previous section of this disclosure, YAG:Ce demonstrates this desired high efficiency with quantum efficiencies greater than about 95%, and thus, improving this number appears to be a daunting task. However, it is known in the art that the efficiency of LED chips increases as the emission wavelength decreases, and therefore, in any case, theoretically, if the phosphors paired with the LED chips emitted at shorter wavelengths can be shorter by them, Wavelength excitation will enhance the efficiency of general lighting systems. Unfortunately, the problem with this strategy is that when the wavelength of the blue excitation radiation of the YAG:Ce phosphor falls below about 460 nm, its emission efficiency is reduced.

當然，此反彈係YAG：Ce實際上僅與具有不小於約450nm至460nm之發射波長的LED晶片配對之情形。但業內亦已知，磷光體之激發輻射之光子能強烈地取決於圍繞激活劑陽離子(鈰)之陰離子多面體之結構(在此情形下包含氧原子)。因而斷定，若以石榴石為主之磷光體之激發範圍相對於YAG：Ce磷光體可朝向較短波長延伸，則可增強系統之效率。因此，本發明之目的包括改變此陰離子多面體之結構及性質以使激發範圍移位，磷光體「期望」在維持(或甚至改良)石榴石展示之優良性質的同時看到比傳統YAG：Ce之波長短之波長。 Of course, this rebound is a case where YAG:Ce is actually only paired with an LED chip having an emission wavelength of not less than about 450 nm to 460 nm. However, it is also known in the art that the photon energy of the excitation radiation of a phosphor strongly depends on the structure of the anionic polyhedron surrounding the activator cation (in this case, an oxygen atom). It is thus concluded that the efficiency of the system can be enhanced if the excitation range of the garnet-based phosphor is extended toward a shorter wavelength relative to the YAG:Ce phosphor. Accordingly, it is an object of the present invention to modify the structure and properties of the anionic polyhedron to shift the excitation range, and the phosphor "expects" to see the superior properties of the garnet display while maintaining (or even improving) the garnet display compared to conventional YAG:Ce A wavelength with a short wavelength.

本發明將分成以下章節：首先將給出本發明之綠色石榴石之化學說明(化學計量式)，之後簡單說明可能合成方法。其後將論述本發 明綠色石榴石之結構、以及其與實驗數據之關係，該實驗數據包含在納入某些鹵素摻雜劑時波長及光致發光變化。最後，利用例示性數據呈遞該等綠色石榴石可在白光照明及背光應用中所起作用。 The invention will be divided into the following sections: First, the chemical description (stoichiometric formula) of the green garnet of the present invention will be given, followed by a brief description of possible synthetic methods. This will be discussed later. The structure of the bright green garnet and its relationship to experimental data, including the wavelength and photoluminescence changes in the incorporation of certain halogen dopants. Finally, the presentation of such green garnets using exemplary data can play a role in white lighting and backlighting applications.

本發明綠色石榴石之化學說明Chemical description of green garnet of the invention

本發明之綠光石榴石含有鹼土金屬及鹵素兩種成份。該等摻雜劑用於達成期望光電發射強度及光譜性質，但鹼土金屬及鹵素同時取代提供一種自給電荷平衡之事實亦係偶然的。另外，可存在與晶胞尺寸的整體變化相關之其他有利補償：儘管用Lu取代Y可往往擴大晶胞之尺寸，但可隨著用鹼土金屬取代Y(在一些情形下，以任一速率)出現相反效應，且用鹵素取代氧亦如此。 The green garnet of the present invention contains an alkaline earth metal and a halogen component. These dopants are used to achieve the desired photoemission intensity and spectral properties, but the fact that alkaline earth metals and halogens simultaneously provide a self-contained charge balance is also accidental. In addition, there may be other advantageous compensations associated with an overall change in unit cell size: although substitution of Y with Lu may tend to increase the size of the unit cell, it may be replaced with an alkaline earth metal (in some cases, at any rate). The opposite effect occurs, as is the replacement of oxygen with a halogen.

有若干方式闡述本發明磷光體之式。在一個實施例中，摻雜鈰之以石榴石為主之黃光至綠光磷光體可由式(Lu_1-a-b-cY_aTb_bA_c)₃(Al_1-dB_d)₅(O_1-eC_e)₁₂：Ce,Eu表示，其中A選自由Mg、Sr、Ca及Ba組成之群；B選自由Ga及In組成之群；C選自由F、Cl及Br組成之群；0a1；0b1；0<c0.5；0d1；且0<e0.2。單獨或組合使用之「A」元素可為鹼土金屬元素Mg、Sr、Ca及Ba中之任一者，其極有效地使波長移位至較短值。該等化合物在本發明中可稱作「以鹵化LAG為主」之石榴石。 There are several ways to illustrate the form of the phosphor of the present invention. In one embodiment, the garnet-doped yellow-to-green phosphor that is doped with yttrium may be of the formula (Lu _1-abc Y _a Tb _b A _c ) ₃ (Al _1-d B _d ) ₅ (O _{1 -e} C _e ) ₁₂ : Ce, Eu denotes wherein A is selected from the group consisting of Mg, Sr, Ca and Ba; B is selected from the group consisting of Ga and In; C is selected from the group consisting of F, Cl and Br; a 1;0 b 1;0<c 0.5;0 d 1; and 0<e 0.2. The "A" element used singly or in combination may be any of the alkaline earth metal elements Mg, Sr, Ca, and Ba, which are extremely effective in shifting the wavelength to a shorter value. These compounds may be referred to as "garbage-based LAG" garnets in the present invention.

在替代實施例中，本發明之綠色石榴石可由式(Y,Lu,A)_x(Al)₅(O,F,Cl)_12+(3/2)x表示；限制條件為x不等於3，且在約2.5至約3.5之範圍內。如在此節中所述之第一式中，A選自由Mg、Sr、Ca及Ba組成之群，且相對於釔及鎦之總量，化學計量含量在大於0至約0.5之範圍內。釔及鎦彼此可互換。該等化合物在本發明中可籠統闡述為「以YAG及LAG為主」之「非整數化學計量化合物」。 In an alternative embodiment, the green garnet of the present invention may be represented by the formula (Y, Lu, A) _x (Al) ₅ (O, F, Cl) _{12+ (3/2) x} ; the constraint is that x is not equal to 3 And in the range of from about 2.5 to about 3.5. As in the first formula described in this section, A is selected from the group consisting of Mg, Sr, Ca, and Ba, and the stoichiometric content is in the range of more than 0 to about 0.5 with respect to the total amount of lanthanum and cerium.钇 and 镏 are interchangeable with each other. These compounds are generally described in the present invention as "non-integer stoichiometric compounds" which are "mainly YAG and LAG".

在替代實施例中，本發明之以石榴石為主之綠光磷光體可由式(Y,A)₃(Al,B)₅(O,C)₁₂：Ce³⁺闡述，其中A係Tb、Gd、Sm、La、Lu、Sr、 Ca及Mg中之至少一者，包括彼等元素之組合，其中彼等元素對Y之取代量以化學計量方式在約0.1%至約100%範圍內。B係Si、Ge、B、P及Ga中之至少一者，包括其組合，且該等元素以在約0.1至約100化學計量百分比範圍內之量取代Al。C係F、Cl、N及S中之至少一者，包括其組合，以在約0.1至約100化學計量百分比範圍內之量取代氧。 In an alternative embodiment, the garnet-based green phosphor of the present invention can be illustrated by the formula (Y, A) ₃ (Al, B) ₅ (O, C) ₁₂ : Ce ³⁺ , wherein the A is Tb, At least one of Gd, Sm, La, Lu, Sr, Ca, and Mg, including combinations of elements thereof, wherein the amount of substitution of these elements for Y is stoichiometrically in the range of from about 0.1% to about 100%. At least one of B-type Si, Ge, B, P, and Ga, including combinations thereof, and the elements replace Al with an amount ranging from about 0.1 to about 100 stoichiometric percent. At least one of the C systems F, Cl, N, and S, including combinations thereof, replaces oxygen in an amount ranging from about 0.1 to about 100 stoichiometric percent.

在替代實施例中，本發明之以石榴石為主之綠光磷光體可由式(Y_1-xBa_x)₃Al₅(O_1-yC_y)₁₂：Ce³⁺闡述，其中x及y各自在約0.001至約0.2之範圍內。在此實施例之變化形式中，以石榴石為主之磷光體可由式(Y_1-xBa_x)_zAl₅(O_1-yC_y)_12+(3/2)z：Ce³⁺表示，其中在此實施例中z不等於3，且在約2.5至約3.5之範圍內。在該等實施例中，在構成元素係釔、鋇、鋁、氧及氟時，磷光體由波長範圍為約440nm至約470nm之輻射激發，且呈現峰發射波長作為約540nm至約560nm範圍內之結果。 In an alternative embodiment, the garnet-based green phosphor of the present invention can be illustrated by the formula (Y _1-x Ba _x ) ₃ Al ₅ (O _1-y C _y ) ₁₂ :Ce ³⁺ , wherein x and y are each in the range of from about 0.001 to about 0.2. In a variation of this embodiment, the garnet-based phosphor may be of the formula (Y _1-x Ba _x ) _z Al ₅ (O _1-y C _y ) _12+(3/2)z :Ce ³⁺ It is indicated that z is not equal to 3 in this embodiment and is in the range of from about 2.5 to about 3.5. In such embodiments, the phosphor is excited by radiation having a wavelength in the range of from about 440 nm to about 470 nm and exhibits a peak emission wavelength in the range of from about 540 nm to about 560 nm when the constituent elements are lanthanum, cerium, aluminum, oxygen, and fluorine. The result.

合成synthesis

可使用任一數量之方法合成本發明以石榴石為主之綠光磷光體，其包括固態反應機制以及液體混合技術二者。液體混合包括共沉澱及溶膠-凝膠技術等方法。 The garnet-based green phosphor of the present invention can be synthesized using any number of methods, including both solid state reaction mechanisms and liquid mixing techniques. Liquid mixing includes methods such as coprecipitation and sol-gel techniques.

製備之一個實施例包括固態反應機制，其包含以下步驟：(a)組合期望量之起始材料CeO₂、Y₂O₃、鎦鹽(包括鎦之硝酸鹽、碳酸鹽、鹵化物、及/或氧化物)及M²⁺X₂(其中M係選自由Mg、Sr、Ca及Ba組成之群之二價鹼土金屬，且X係選自由F及Cl組成之群之鹵素)以形成起始粉末之混合物；(b)使用任一習用方法(例如球磨)乾式混合步驟(a)之起始粉末混合物，且使用球磨之典型混合時間大於約2小時(在一個實施例中約8小時)；(c)在約1400℃至約1600℃之溫度下在還原氣氛(此氣氛之目的係還原以氨為主之化合物)中將步驟(b)之混合起始粉末燒結約6至約12小 時；(d)壓碎步驟(c)之燒結產物，並用水對其進行洗滌；及(e)乾燥步驟(d)之洗滌產物，其中乾燥條件可為在約150℃之溫度下約12小時之時間。 One embodiment of the preparation comprises a solid state reaction mechanism comprising the steps of: (a) combining a desired amount of starting materials CeO ₂ , Y ₂ O ₃ , cerium salts (including cerium nitrates, carbonates, halides, and/or Or an oxide) and M ²⁺ X ₂ (wherein M is selected from the group consisting of Mg, Sr, Ca, and Ba, a divalent alkaline earth metal, and X is selected from the group consisting of halogens of F and Cl) to form an onset a mixture of powders; (b) dry blending the starting powder mixture of step (a) using any conventional method (eg, ball milling), and using a ball mill for a typical mixing time of greater than about 2 hours (about 8 hours in one embodiment); (c) sintering the mixed starting powder of step (b) for about 6 to about 12 hours in a reducing atmosphere (the atmosphere is intended to reduce ammonia-based compounds) at a temperature of from about 1400 ° C to about 1600 ° C; (d) crushing the sintered product of step (c) and washing it with water; and (e) drying the washed product of step (d), wherein the drying condition may be at a temperature of about 150 ° C for about 12 hours. .

本發明石榴石亦可藉由液體混合技術合成。使用共沉澱合成具有式Lu_2.985Ce_0.015Al₅O₁₂之非鹵化LAG化合物之實例已由H.-L.Li等人闡述於標題為「Fabrication of Transparent Cerium-Doped Lutetium Aluminum Garnet Ceramics by Co-Precipitation Routes，」之論文，J.Am.Ceram.Soc.89[7]2356-2358(2006)中。該等非鹵化LAG化合物不含鹼土金屬成份。該論文之全文併入本文中，如所預計一樣，類似共沉澱方法可用於產生本發明具有鹼土金屬成份之鹵化LAG。 The garnet of the present invention can also be synthesized by liquid mixing techniques. An example of synthesizing a non-halogenated LAG compound having the formula Lu _2.985 Ce _0.015 Al ₅ O ₁₂ using coprecipitation has been described by H.-L. Li et al. in "Fabrication of Transparent Cerium-Doped Lutetium Aluminum Garnet Ceramics by Co-Precipitation. Routes," paper, J. Am. Ceram. Soc. 89 [7] 2356-2358 (2006). The non-halogenated LAG compounds are free of alkaline earth metal components. The full text of this paper is incorporated herein, and as expected, a coprecipitation-like process can be used to produce the halogenated LAG of the present invention having an alkaline earth metal component.

使用溶膠-凝膠技術合成鹵化YAG化合物之實例已闡述於E.McFarland等人(Symyx Technologies)標題為「Phosphor materials」之美國專利6,013,199之中。該等(可能)鹵化YAG化合物不含鹼土金屬成份。此專利之全文併入本文中，如所預計一樣，類似溶膠-凝膠方法可用於產生本發明具有鹼土金屬成份之鹵化YAG化合物。 An example of the synthesis of a halogenated YAG compound using a sol-gel technique is described in U.S. Patent No. 6,013,199 to "Fhosphor materials" by E. McFarland et al. (Symyx Technologies). The (possibly) halogenated YAG compounds are free of alkaline earth metal components. The entire disclosure of this patent is incorporated herein by reference to a similar sol-gel process which can be used to produce the halogenated YAG compounds of the present invention having an alkaline earth metal component.

圖1顯示例示性Lu_2.91Ce_0.09Al₅O₁₂磷光體之SEM形貌，該磷光體具有不同MgF₂添加劑濃度，係經由上述固態機制合成。由掃描電子顯微鏡(SEM)揭示之形貌顯示隨著MgF₂添加劑之量增大，粒徑變大且更均勻。 Figure 1 shows the SEM topography of an exemplary Lu _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor having different MgF ₂ additive concentrations, synthesized via the solid state mechanism described above. The morphology revealed by scanning electron microscopy (SEM) shows that as the amount of MgF ₂ additive increases, the particle size becomes larger and more uniform.

本發明綠色石榴石之結晶結構Crystal structure of green garnet of the invention

本發明綠色石榴石之結晶結構與釔鋁石榴石Y₃Al₅O₁₂之結晶結構相同，且與此充分研究之YAG化合物一樣，本發明石榴石屬於Ia3d空間群(第230號)。關於YAG之此空間群已由Y.Kuru等人闡述於標題為「Yttrium Aluminum Garnet as a Scavenger for Ca and Si」之論文，J.Am.Ceram.Soc.91[11]3663-3667(2008)中。如Y.Kuru等人所述， YAG具有由160個原子(8個式單位)/單位晶胞組成之複晶體，其中Y³⁺佔據多重度24、Wyckoff字母「c」及位點對稱性2.22之位置，且O^2-原子佔據多重度96、Wyckoff字母「h」及位點對稱性1之位置。兩個Al³⁺離子位於八面體16(a)位置上，而剩餘三個Al³⁺離子位於四面體24(d)位點上。 The crystal structure of the green garnet of the present invention is the same as that of the yttrium aluminum garnet Y ₃ Al ₅ O ₁₂ , and like the fully studied YAG compound, the garnet of the present invention belongs to the Ia3d space group (No. 230). This space group for YAG has been described by Y.Kuru et al. in the paper entitled "Yttrium Aluminum Garnet as a Scavenger for Ca and Si", J. Am. Ceram. Soc. 91 [11] 3663-3667 (2008) in. As described by Y. Kuru et al., YAG has a complex crystal composed of 160 atoms (8 units) per unit cell, where Y ³⁺ occupies multiple degrees 24, Wyckoff letter "c" and site symmetry 2.22 The position, and the O ^2- atom occupies the position of the multiplicity of 96, the Wyckoff letter "h", and the site symmetry 1. Two Al ³⁺ ions are located at the octahedron 16 (a) position, while the remaining three Al ³⁺ ions are located at the tetrahedral 24 (d) site.

YAG晶胞之晶格參數係a=b=c=1.2008nm且α=β=γ=90°。而期望用鎦取代釔以擴大晶胞之尺寸，不期望改變晶胞軸之間之角度，且該材料將保留其立方體特徵。 The lattice parameter of the YAG unit cell is a = b = c = 1.2008 nm and α = β = γ = 90 °. It is desirable to replace the germanium with germanium to expand the size of the unit cell, and it is not desirable to change the angle between the unit cell axes, and the material will retain its cubic features.

圖2顯示一系列具有不同MgF₂添加劑濃度之例示性Y_2.91Ce_0.09Al₅O₁₂磷光體的x射線繞射(XRD)圖案，其顯示鹼土金屬及鹵素(MgF₂)組份之添加如何使高角度繞射峰移位至較高2θ值。此意味著晶格常數相對於無鹼土金屬/鹵素之YAG組份變小，且進一步指示Mg²⁺被納入晶格中，佔據Y³⁺位置。 Figure 2 shows a series of x-ray diffraction (XRD) patterns of an exemplary Y _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor with different MgF ₂ additive concentrations, showing how the addition of alkaline earth metal and halogen (MgF ₂ ) components makes The high angle diffraction peak shifts to a higher 2θ value. This means that the lattice constant becomes smaller with respect to the alkaline earth metal/halogen-free YAG component, and further indicates that Mg ²⁺ is incorporated into the crystal lattice, occupying the Y ³⁺ position.

圖3以與圖2類似之方式顯示一系列例示性磷光體之x射線繞射(XRD)圖案，只是此時化合物系列係具有不同MgF₂添加劑濃度之Lu_2.91Ce_0.09Al₅O₁₂磷光體，其中研究以鎦為主之化合物而非以釔為主之化合物。 Figure 3 shows a series of exemplary phosphor x-ray diffraction (XRD) patterns in a similar manner to Figure 2, except that the compound series is a Lu _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor with different MgF ₂ additive concentrations. Among them, compounds based on ruthenium are studied instead of compounds based on ruthenium.

圖4顯示一系列具有5wt% MgF₂及5wt% SrF₂添加劑之例示性Lu_2.91Ce_0.09Al₅O₁₂磷光體的x射線繞射(XRD)圖案：此實驗顯示Mg成份與Sr成份之比較。數據顯示在Lu_2.91Ce_0.09Al₅O₁₂晶格中具有MgF₂添加劑之情況下，高角度繞射峰移動至較大2θ值，此意味著晶格常數變小。或者，在具有SrF₂添加劑之情況下，高角度繞射峰移動至較小2θ值，此意味著晶格常數增大。彼等熟習此項技術者應瞭解，Mg²⁺及Sr²⁺二者均納入Lu_2.91Ce_0.09Al₅O₁₂晶格中並佔據Lu³⁺位置。該等峰發生移位，此乃因離子半徑為0.72Å之Mg²⁺小於Lu³⁺(0.86Å)，而Sr²⁺(1.18Å)大於Lu³⁺。 Figure 4 shows an x-ray diffraction (XRD) pattern of a series of exemplary Lu _2.91 Ce _0.09 Al ₅ O ₁₂ phosphors with 5 wt% MgF ₂ and 5 wt% SrF ₂ additives: this experiment shows a comparison of the Mg component with the Sr component. The data shows that in the case of the MgF ₂ additive in the Lu _2.91 Ce _0.09 Al ₅ O ₁₂ lattice, the high angle diffraction peak shifts to a larger 2θ value, which means that the lattice constant becomes smaller. Alternatively, with the SrF ₂ additive, the high angle diffraction peak moves to a smaller 2θ value, which means that the lattice constant increases. Those skilled in the art will appreciate that both Mg ²⁺ and Sr ²⁺ are incorporated into the Lu _2.91 Ce _0.09 Al ₅ O ₁₂ lattice and occupy the Lu ³⁺ position. These peaks are shifted because Mg ²⁺ with an ionic radius of 0.72 Å is smaller than Lu ³⁺ (0.86 Å), and Sr ²⁺ (1.18 Å) is larger than Lu ³⁺ .

鹼土金屬及鹵素對光學性質之影響的機制Mechanism of the influence of alkaline earth metals and halogens on optical properties

石為主之磷光體中之發光激活劑。Ce³⁺離子之4f與5d能階之間的躍遷對應於用藍光激發磷光體；自磷光體發射綠光係相同電子躍遷之結果。在石榴石結構中，Ce³⁺位於由六個氧離子之多陰離子結構形成的八面體位點之中心。彼等熟習此項技術者應瞭解，根據結晶領域理論，周圍陰離子(其亦闡述為配體)包括中心陽離子之5d電子上的靜電勢。5d能階***係10Dq，其中已知Dq取決於特定配體物質。自光譜化學系列可觀察到鹵化物之Dq小於氧之Dq，且因此斷定，在氧離子由鹵離子替代時，Dq將相應地減小。 A luminescent activator in a stone-based phosphor. The transition between the 4f and 5d energy levels of the Ce ³⁺ ion corresponds to the excitation of the phosphor with blue light; the result of the same electronic transition from the green light emission of the phosphor. In the garnet structure, Ce ³⁺ is located at the center of the octahedral site formed by the polyanion structure of six oxygen ions. Those skilled in the art will appreciate that, according to the theory of crystallization, the surrounding anion (which is also described as a ligand) includes the electrostatic potential on the 5d electron of the central cation. The 5d energy cascade system 10Dq, where Dq is known to depend on the particular ligand species. It is observed from the spectral chemistry series that the Dq of the halide is less than the Dq of oxygen, and therefore it is concluded that Dx will be correspondingly reduced when the oxygen ions are replaced by halide ions.

此暗示帶隙能量(換言之，4f與5d電子能階之間之能量差)將隨著在圍繞激活劑離子之多陰離子籠中氧離子經鹵離子取代而增大。此係為何發射峰隨著鹵素取代而移位至較短波長的原因。同時，在形成八面體位點之氧多陰離子結構中引入鹵離子之情況下，相應陽離子亦可替代一部分Lu/Y含量。若替代Lu/Y之陽離子係較小陽離子，則結果將為發射峰朝向光譜之藍色末端移位。所發射螢光將具有比原本可發生之波長短之波長。相反地，若替代Lu/Y之陽離子係較大陽離子(例如Sr或Ba)，則結果將為發射峰朝向光譜之紅色末端移位。在此情形下，所發射螢光將具有較長波長。 This implies that the band gap energy (in other words, the energy difference between the 4f and 5d electron energy levels) will increase as the oxygen ions are replaced by halide ions in the polyanion cage surrounding the activator ions. This is why the emission peak shifts to a shorter wavelength with halogen substitution. At the same time, in the case where a halide ion is introduced into the oxygen polyanion structure forming the octahedral site, the corresponding cation can also replace a part of the Lu/Y content. If the cation of Lu/Y is substituted for a smaller cation, the result will be an emission peak shifting towards the blue end of the spectrum. The emitted fluorescent light will have a wavelength that is shorter than the wavelength that would otherwise occur. Conversely, if the cation replacing Lu/Y is a larger cation (such as Sr or Ba), the result will be that the emission peak shifts towards the red end of the spectrum. In this case, the emitted fluorescent light will have a longer wavelength.

與鹵化物之效應組合，若期望藍移，則作為鹼土金屬取代物之Mg將為比Sr更好之選擇，且此將以實驗方式顯示於本發明之以下部分中。亦已知LAG發射峰由於自旋軌道耦合而為雙峰。在發生藍移時，具有較短波長之發射偏移且其強度相應增大。此趨勢不僅有助於發射之藍移，而且亦增強光致發光。 In combination with the effect of the halide, if blue shift is desired, Mg as an alkaline earth metal substitute will be a better choice than Sr and this will be shown experimentally in the following sections of the invention. It is also known that the LAG emission peak is bimodal due to spin-orbit coupling. When a blue shift occurs, the emission shift with a shorter wavelength and its intensity increases accordingly. This trend not only contributes to the blue shift of the emission, but also enhances the photoluminescence.

圖5係一系列具有不同MgF₂添加劑含量之例示性Y_2.91Ce_0.09Al₅O₁₂磷光體之發射光譜，該發射光譜係藉由用藍色LED激發磷光體獲得。此數據顯示隨著MgF₂之量增大，光致發光強度增大且峰發射波長移 位至較短值。儘管在圖5上未顯示，但本發明者具有針對在起始粉末中添加5wt% BaF₂之數據：此磷光體顯示相對於該三個含鎂磷光體，光致發光強度顯著增大，且峰發射波長與1wt%試樣之峰發射波長大約相同。 Figure 5 is a series of emission spectra of an exemplary Y _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor having different MgF ₂ additive contents obtained by exciting a phosphor with a blue LED. This data shows that as the amount of MgF ₂ increases, the photoluminescence intensity increases and the peak emission wavelength shifts to a shorter value. Although not shown in Figure 5, the inventors have data for the addition of 5 wt% BaF _{2 to} the starting powder: this phosphor shows a significant increase in photoluminescence intensity relative to the three magnesium-containing phosphors, and The peak emission wavelength is approximately the same as the peak emission wavelength of the 1 wt% sample.

圖5之數據的正規化版本示於圖6中。圖6係在藍色LED激發下相同系列的具有不同MgF₂添加劑濃度之例示性Y_2.91Ce_0.09Al₅O₁₂磷光體的正規化發射光譜，但其中將光致發光強度正規化至單一值以突出Y_2.91Ce_0.09Al₅O₁₂之發射峰隨著MgF₂添加劑之量增大而移位至短波長。MgF₂添加劑之量越大，則發射峰波長越短。此係與由Lu_2.91Ce_0.09Al₅O₁₂磷光體所展示者相同之趨勢，如其後將證實。 The normalized version of the data of Figure 5 is shown in Figure 6. Figure 6 is a normalized emission spectrum of an exemplary series of exemplary Y _2.91 Ce _0.09 Al ₅ O ₁₂ phosphors having different MgF ₂ additive concentrations excited by a blue LED, but wherein the photoluminescence intensity is normalized to a single value The emission peak of the prominent Y _2.91 Ce _0.09 Al ₅ O ₁₂ shifts to a short wavelength as the amount of the MgF ₂ additive increases. The larger the amount of the MgF ₂ additive, the shorter the emission peak wavelength. This is the same trend as that exhibited by the Lu _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor, as will be confirmed later.

圖7係一系列具有不同MgF₂添加劑含量之例示性Lu_2.91Ce_0.09Al₅O₁₂磷光體之發射光譜，該發射光譜係藉由用藍色LED激發磷光體而獲得。此數據類似於圖5之數據，只是研究以鎦為主而非以釔為主之化合物。與釔數據一樣，鎦之此數據顯示發射波長之移位的類似趨勢，但光致發光強度之彼等趨勢可能不類似。 Figure 7 is a series of emission spectra of an exemplary Lu _2.91 Ce _0.09 Al ₅ O ₁₂ phosphor having different MgF ₂ additive contents obtained by exciting a phosphor with a blue LED. This data is similar to the data in Figure 5, except that compounds based on sputum rather than sputum are studied. As with the 钇 data, this data shows a similar trend in the shift of the emission wavelength, but the trends in photoluminescence intensity may not be similar.

圖7之Lu_2.91Ce_0.09Al₅O₁₂發射光譜已經正規化以強調添加鹵素鹽對峰發射波長之效應；數據之正規化版本示於圖8中。如在釔情形下，隨著MgF₂添加劑之量增大，峰發射移位至較短波長；換言之，MgF₂添加劑之量越大，則發射峰波長越短。在MgF₂添加劑之量自0(無添加劑)增大至約5wt%添加劑時，觀察到波長移位之量為約40nm；自約550nm移位至約510nm。 The Lu _2.91 Ce _0.09 Al ₅ O ₁₂ emission spectrum of Figure 7 has been normalized to emphasize the effect of the addition of a halogen salt on the peak emission wavelength; the normalized version of the data is shown in Figure 8. As in the case of ruthenium, as the amount of MgF ₂ additive increases, the peak emission shifts to a shorter wavelength; in other words, the larger the amount of the MgF ₂ additive, the shorter the emission peak wavelength. When the amount of MgF ₂ additive was increased from 0 (no additive) to about 5 wt% additive, the amount of wavelength shift was observed to be about 40 nm; shifting from about 550 nm to about 510 nm.

圖5至8中之每一圖表將其各自光譜繪示為具有增大添加劑濃度之一系列磷光體組合物(以無添加劑開始，且以5wt%之系列之最高濃度結束)。為強調SrF₂添加劑與MgF₂添加劑之比較；換言之，具有Sr鹼土金屬及氟含量之磷光體與具有Mg鹼土金屬及氟含量之磷光體，已一起將磷光體繪示於圖9中：無添加劑之磷光體、具有5wt% SrF₂ 之磷光體及具有5wt% MgF₂之磷光體。磷光體係以試樣Lu_2.91Ce_0.09Al₅O₁₂為主。 Each of Figures 5 through 8 plots their respective spectra as a series of phosphor compositions with increasing additive concentrations (starting with no additives and ending with the highest concentration of the 5 wt% series). To emphasize the comparison of the SrF ₂ additive with the MgF ₂ additive; in other words, the phosphor having the Sr alkaline earth metal and fluorine content and the phosphor having the Mg alkaline earth metal and fluorine content, together with the phosphor are shown in Figure 9: no additives Phosphor, phosphor with 5 wt% SrF ₂ and phosphor with 5 wt% MgF ₂ . The phosphorescence system was dominated by the sample Lu _2.91 Ce _0.09 Al ₅ O ₁₂ .

圖9中之發射光譜數據已經正規化以更好地強調對因納入鹵素及鹼土金屬產生之光學性質的效應。在用藍色LED激發時，結果闡釋在添加MgF₂及SrF₂下，發射峰移位至較短波長。無添加劑之Lu_2.91Ce_0.09Al₅O₁₂試樣於約550nm下顯示峰發射波長；具有5wt% SrF₂添加劑之峰發射波長移位至約535nm，且具有5wt% MgF₂添加劑之波長甚至進一步移位至約510nm。 The emission spectral data in Figure 9 has been normalized to better emphasize the effects on the optical properties produced by the inclusion of halogens and alkaline earth metals. When excited with a blue LED, the results illustrate that the emission peak shifts to a shorter wavelength with the addition of MgF ₂ and SrF ₂ . The additive-free Lu _2.91 Ce _0.09 Al ₅ O ₁₂ sample showed a peak emission wavelength at about 550 nm; the peak emission wavelength with a 5 wt% SrF ₂ additive shifted to about 535 nm, and the wavelength with 5 wt% MgF ₂ additive was even further shifted Bit to about 510 nm.

圖10顯示隨著SrF₂添加劑之濃度增大，一系列例示性Lu_2.91Ce_0.09Al₅O₁₂磷光體之發射波長如何減小。峰發射波長已繪示為隨SrF₂添加劑之量變化；測試具有1wt%、2wt%、3wt%及5wt%之SrF₂添加劑含量的試樣。結果顯示對於1wt%及2wt%試樣，峰發射波長大約相同，波長為約535nm；隨著SrF₂添加劑增大至3wt%，峰發射波長減小至約533nm。在SrF₂添加劑進一步增大至5wt%下，峰波長急劇下降至約524nm。 Figure 10 shows how the emission wavelength of a series of exemplary Lu _2.91 Ce _0.09 Al ₅ O ₁₂ phosphors decreases as the concentration of the SrF ₂ additive increases. Peak emission wavelength is shown as an amount of SrF ₂ with variation of the additive; test having 1wt%, 2wt%, Sample _2, and the additive content of 5wt% 3wt% of SrF. The results show that for 1 wt% and 2 wt% samples, the peak emission wavelength is about the same, the wavelength is about 535 nm; as the SrF ₂ additive increases to 3 wt%, the peak emission wavelength is reduced to about 533 nm. When the SrF ₂ additive was further increased to 5 wt%, the peak wavelength sharply dropped to about 524 nm.

激發光譜及溫度依賴性Excitation spectrum and temperature dependence

圖11係一系列具有不同MgF₂添加劑濃度之例示性Lu_2.91Ce_0.09Al₅O₁₂磷光體的正規化激發光譜，其顯示在MgF₂添加劑濃度增大時，激發光譜變更窄。數據顯示本發明綠色石榴石呈現超出磷光體可被激發之寬波長頻帶，在約380nm至約480nm範圍內。 Figure 11 is a normalized excitation spectrum of a series of exemplary Lu _2.91 Ce _0.09 Al ₅ O ₁₂ phosphors having different concentrations of MgF ₂ additive, showing a narrow change in excitation spectrum as the concentration of MgF ₂ additive increases. The data shows that the green garnet of the present invention exhibits a broad wavelength band beyond which the phosphor can be excited, in the range of from about 380 nm to about 480 nm.

本發明石榴石磷光體之熱穩定性係由具有5wt% MgF₂添加劑之含鎦化合物Lu_2.91Ce_0.09Al₅O₁₂例示；在圖12中比較其與市售磷光體Ce³⁺：Y₃Al₅O₁₂之熱穩定性。可觀察到Lu_2.91Ce_0.09Al₅O₁₂化合物之熱穩定性甚至比YAG更好。 The thermal stability of the garnet phosphor of the present invention is exemplified by the cerium-containing compound Lu _2.91 Ce _0.09 Al ₅ O ₁₂ having 5 wt% MgF ₂ additive; compared with the commercially available phosphor Ce ³⁺ : Y ₃ Al in Fig. 12 ₅ O ₁₂ thermal stability. It can be observed that the thermal stability of the Lu _2.91 Ce _0.09 Al ₅ O ₁₂ compound is even better than YAG.

背光及白光照明系統應用Backlight and white lighting system applications

根據本發明之其他實施例，本發明綠色石榴石可用於白光照明 系統(通常稱作「白色LED」)中及以背光組態用於顯示應用。此一白光照明系統包含經構造可發射波長大於約280nm之輻射的輻射源；及摻雜鹵陰離子之綠色石榴石磷光體，該磷光體經構造可吸收至少部分來自輻射源的輻射並發射峰波長在480nm至約650nm範圍內之光。 According to other embodiments of the present invention, the green garnet of the present invention can be used for white light illumination The system (often referred to as "white LED") and configured in backlight for display applications. The white light illumination system includes a radiation source configured to emit radiation having a wavelength greater than about 280 nm; and a green garnet phosphor doped with a halide anion configured to absorb at least a portion of the radiation from the radiation source and emit a peak wavelength Light in the range of 480 nm to about 650 nm.

圖13顯示白色LED之光譜，該白色LED包括具有式Lu_2.91Ce_0.09Al₅O₁₂且具有5wt.% SrF₂添加劑之例示性以石榴石為主之綠光磷光體。此白色LED進一步包括具有式(Ca_0.2Sr_0.8)AlSiN₃：Eu²⁺之紅色磷光體。在用發射藍光之InGaN LED激發綠色石榴石及紅色氮化物磷光體二者時，所得白光展示色彩坐標CIE x=0.24，且CIE y=0.20。圖13中之試樣含有黃色-綠色矽酸鹽。 Figure 13 shows the spectrum of a white LED comprising an exemplary garnet-based green phosphor having the formula Lu _2.91 Ce _0.09 Al ₅ O ₁₂ and having a 5 wt.% SrF ₂ additive. This white LED further includes a red phosphor having the formula (Ca _0.2 Sr _0.8 )AlSiN ₃ :Eu ²⁺ . When both green garnet and red nitride phosphor were excited with a blue-emitting InGaN LED, the resulting white light exhibited a color coordinate CIE x = 0.24 and CIE y = 0.20. The sample in Figure 13 contains yellow-green citrate.

圖14係具有以下組份之白色LED之光譜：藍色InGaN LED、具有3wt%或5wt%添加劑且具有式Lu_2.91Ce_0.09Al₅O₁₂之綠色石榴石、具有式(Ca_0.2Sr_0.8)AlSiN₃：Eu²⁺之紅色氮化物或具有式(Sr_0.5Ba_0.5)₂SiO₄：Eu²⁺之矽酸鹽，其中白光具有色彩座標CIE(x=0.3,y=0.3)。顯示最突出雙峰之試樣係標記「EG3261+R640」者，其中EG3261標幟代表(Sr_0.5Ba_0.5)₂SiO₄：Eu²⁺磷光體與在約640nm下發射之紅色R640(Ca_0.2Sr_0.8)AlSiN₃：Eu²⁺磷光體的組合。標記LAG(3wt% MgF₂)+R640及LAG(5wt% SrF₂)+R640之兩個峰證實在500nm至650nm之波長範圍內所感知白光更均勻發射，此為業內所期望屬性。 Figure 14 is a spectrum of white LEDs with the following composition: blue InGaN LED, green garnet with 3 wt% or 5 wt% additive and having the formula Lu _2.91 Ce _0.09 Al ₅ O ₁₂ , having the formula (Ca _0.2 Sr _0.8 ) AlSiN ₃ : a red nitride of Eu ²⁺ or a bismuth salt of the formula (Sr _0.5 Ba _0.5 ) ₂ SiO ₄ :Eu ²⁺ , wherein the white light has a color coordinate CIE (x=0.3, y=0.3). The sample showing the most prominent double peak is labeled "EG3261+R640", wherein the EG3261 marker represents (Sr _0.5 Ba _0.5 ) ₂ SiO ₄ :Eu ²⁺ phosphor and the red R640 (Ca _0.2 Sr emitted at about 640 nm) _0.8 ) Combination of AlSiN ₃ :Eu ²⁺ phosphors. Two peaks labeled LAG (3 wt% MgF ₂ ) + R640 and LAG (5 wt % SrF ₂ ) + R640 demonstrate a more uniform emission of perceived white light in the wavelength range from 500 nm to 650 nm, which is a desirable property in the industry.

圖15係圖14之白色LED系統之光譜，在此情況下在3,000K下量測。 Figure 15 is a spectrum of the white LED system of Figure 14, in this case measured at 3,000K.

在本發明之實施例中，可與綠色石榴石結合使用之紅色氮化物可具有通式(Ca,Sr)AlSiN₃：Eu²⁺，其中紅色氮化物可進一步包含可選鹵素，且其中紅色氮化物磷光體中之氧雜質含量可小於等於約2重量%。 In an embodiment of the invention, the red nitride that can be used in combination with the green garnet may have the general formula (Ca,Sr)AlSiN ₃ :Eu ²⁺ , wherein the red nitride may further comprise an optional halogen, and wherein the red nitrogen The content of oxygen impurities in the phosphor may be less than or equal to about 2% by weight.

呈表形式之光學及物理數據Optical and physical data in tabular form

例示性數據之概述列示於以下兩個表中。表1係具有三個不同MgF₂添加劑含量之以Lu_2.91Ce_0.09Al₅O₁₂為主之磷光體的測試結果。表2列示具有四種不同重量百分比之SrF₂添加劑之以Lu_2.91Ce_0.09Al₅O₁₂為主之化合物的測試結果。該等結果概述並確認Lu_2.91Ce_0.09Al₅O₁₂中之MgF₂及SrF₂添加劑將發射峰波長移位至較短波長，其中發射強度隨著MgF₂及SrF₂濃度之增大而增大。粒徑亦隨著MgF₂及SrF₂添加劑濃度之增大而增大。 An overview of the illustrative data is presented in the following two tables. Table 1 shows the results of a phosphor with Lu _2.91 Ce _0.09 Al ₅ O ₁₂ as the main component having three different MgF ₂ additive contents. Table 2 shows the test results of compounds based on Lu _2.91 Ce _0.09 Al ₅ O ₁₂ with four different weight percentages of SrF ₂ additive. These results summarize and confirm that the MgF ₂ and SrF ₂ additives in Lu _2.91 Ce _0.09 Al ₅ O ₁₂ shift the emission peak wavelength to a shorter wavelength, where the emission intensity increases as the concentration of MgF ₂ and SrF ₂ increases. . The particle size also increases as the concentration of the MgF ₂ and SrF ₂ additives increases.

Claims (5)

一種以石榴石為主之綠光磷光體，其具有式：(Lu_1-a-b-cY_aTb_bA_c)₃(Al_1-dB_d)₅(O_1-eC_e)₁₂：Ce，其中A係選自由Mg、Sr、Ca及Ba組成之群；B係選自由Ga及In組成之群；C係選自由F、Cl及Br組成之群；且0a1；0b1；0<c0.5；0d1；且0<e0.2。 A garnet-based green phosphor having the formula: (Lu _1-abc Y _a Tb _b A _c ) ₃ (Al _1-d B _d ) ₅ (O _1-e C _e ) ₁₂ :Ce, Wherein A is selected from the group consisting of Mg, Sr, Ca, and Ba; B is selected from the group consisting of Ga and In; and C is selected from the group consisting of F, Cl, and Br; a 1;0 b 1;0<c 0.5;0 d 1; and 0<e 0.2. 一種以石榴石為主之綠光磷光體，其具有式：(Y,A)₃(Al,B)₅(O,C)₁₂：Ce，其中A係Tb、Gd、Sm、La、Lu、Sr、Ca及Mg中之至少一者，包括彼等元素之組合，且其中彼等元素對Y之取代量在約0.1至約100化學計量百分比範圍內；B係Si、Ge、B、P及Ga中之至少一者，包括其組合，其中B以在約0.1至約100化學計量百分比範圍內之量取代Al；且C係F、Cl、N及S中之至少一者，包括其組合，其中C以在約0.1至約100化學計量百分比範圍內之量取代氧。 A garnet-based green phosphor having the formula: (Y, A) ₃ (Al, B) ₅ (O, C) ₁₂ : Ce, wherein A is Tb, Gd, Sm, La, Lu, At least one of Sr, Ca and Mg, including combinations of the elements thereof, wherein the substitution amount of these elements for Y is in the range of from about 0.1 to about 100 stoichiometric percentages; B-based Si, Ge, B, P and At least one of Ga, including combinations thereof, wherein B replaces Al in an amount ranging from about 0.1 to about 100 stoichiometric percent; and C is at least one of F, Cl, N, and S, including combinations thereof, Wherein C is substituted for oxygen in an amount ranging from about 0.1 to about 100 stoichiometric percent. 一種以石榴石為主之綠光磷光體，其具有式：(A_1-x ³⁺B_x ²⁺)_mAl₅(O_1-y ^2-C_y ^1-)_n：Ce，其中A係選自由Y、Sc、Gd、Tb及Lu組成之群；B係選自由Mg、Sr、Ca及Ba組成之群； C係選自由F、Cl及Br組成之群；0x0.5；0<y0.5；2m4；且10n14。 A garnet-based green light phosphor having the formula: (A _1-x ³⁺ B _x ²⁺ ) _m Al ₅ (O _1-y ^2- C _y ^1- ) _n :Ce, wherein the A system Select a group consisting of Y, Sc, Gd, Tb and Lu; B is selected from the group consisting of Mg, Sr, Ca and Ba; C is selected from the group consisting of F, Cl and Br; x 0.5;0<y 0.5; 2 m 4; and 10 n 14. 一種以石榴石為主之綠光磷光體，其具有式：(A_1-x ³⁺B_x ²⁺)_mAl₅(O_1-y ^2-C_y ^1-)_n：Ce，其中A係選自由Y、Sc、Gd、Tb及Lu組成之群；B係選自由Mg、Sr、Ca及Ba組成之群；C係選自由F、Cl及Br組成之群；0x0.5；0y0.5；2m4；且10n14；限制條件為m不等於3。 A garnet-based green light phosphor having the formula: (A _1-x ³⁺ B _x ²⁺ ) _m Al ₅ (O _1-y ^2- C _y ^1- ) _n :Ce, wherein the A system Select a group consisting of Y, Sc, Gd, Tb and Lu; B is selected from the group consisting of Mg, Sr, Ca and Ba; C is selected from the group consisting of F, Cl and Br; x 0.5;0 y 0.5; 2 m 4; and 10 n 14; the constraint is that m is not equal to 3. 一種以石榴石為主之綠光磷光體，其具有式：(A_1-x ³⁺B_x ²⁺)_mAl₅(O_1-y ^2-C_y ^1-)_n：Ce，其中A係選自由Y、Sc、Gd、Tb及Lu組成之群；B係選自由Mg、Sr、Ca及Ba組成之群；C係選自由F、Cl及Br組成之群；0x0.5；0y0.5；2m4；且10n14；限制條件為n不等於12。 A garnet-based green light phosphor having the formula: (A _1-x ³⁺ B _x ²⁺ ) _m Al ₅ (O _1-y ^2- C _y ^1- ) _n :Ce, wherein the A system Select a group consisting of Y, Sc, Gd, Tb and Lu; B is selected from the group consisting of Mg, Sr, Ca and Ba; C is selected from the group consisting of F, Cl and Br; x 0.5;0 y 0.5; 2 m 4; and 10 n 14; the constraint is that n is not equal to 12.