TW556365B - Method to fabricate LED for white light source - Google Patents

Abstract

A method to fabricate LED for white light source is disclosed, which utilizes a semiconductor fluorescent body with an LED to fabricate a white light source. The main components of the semiconductor fluorescent body is (Zn, Cd)S, in which one or more different ions are doped in the structure as the light-emitting centers excited by the external light source. The external light source of the present invention can be generated by using an LED emitting a proper wavelength, wherein the wavelength can be ranged from 495 nm blue-green light to 340nm ultraviolet light. After mixing the semiconductor fluorescent body with the packaging material in an appropriate ratio and packaging the same, an LED for white light source with good light-emitting characteristics can be obtained by applying a very low current. Also, the chemical composition of the semiconductor fluorescent body of the present invention can be adjusted, so that it can be excited by an LED to generate one or more colors of fluorescent light for color-mixing to form the white light. That is, a single powder body can be used to fabricate LED for white light source with high-luminance and high color-deriving characteristics.

Description

556365 556365

V. Description of the invention (1) [Field of the invention] The present invention is a method for manufacturing a white light emitting diode light source, and a method for manufacturing a light source using a semiconductor-type phosphor and a light emitting diode (LED). This semiconductor plastic phosphor is mainly composed of sulfide (zinc, pick white [(Zn Cd) S]), which is composed of one or more kinds of ions, and can be excited by a light emitting diode to emit fluorescent light. The light emitted from the light-emitting diode is mixed with light to produce white light, and the light produces a high-brightness white light-emitting diode. ^ Can [Background of the Invention] White light is a multi-color mixture Light can be perceived by the human eye as white light, including at least two wavelengths of mixed light. For example, when the human eye is stimulated by red, blue, and green light at the same time, or by the number of spines of blue and yellow light at the same time. According to this principle, a white light-emitting LED light source can be produced according to this principle. Xi. There are five main methods for manufacturing white LEDs: The first method is to use AlInGaP, NiGaN, and InGaN. Gallium Phosphide (GaP) is made of three LE1), which emits red, green and blue light through the current of the LED. Because these three crystal grains are placed in the same bulb (1 amp), the lens can add the emitted light. The second method is to use InGaN and A1 InGaP or GaP as an LED. Controlled by the LED current to emit blue and yellow-green light to produce white light. At present, the luminous efficiency of these two methods can reach 20lm / w. The second type was developed in 1996 by Nichia Chemical Co., Ltd. (Nichia C h e mi c a 1).

556365 V. Description of the invention ㈣ ^ stone-type fluorescent powder can also become-white light source. & The efficiency is currently up to 20 lra / W. Because only one set of LED chips is needed, the big one: reducing the manufacturing cost, coupled with the matching fluorescent powder, the products have been presented. 〇Healing The fourth solution that can produce white light was developed by Sumitomo Electric (—, Ltd) in January 1991. White light LEDs using ZnSe materials were first developed.

A CdZnSe thin film is formed on the board. After being energized, the thin film emits blue light. At the same time, the blue light emitted by the lamp is irradiated on the substrate to emit yellow light. Finally, the blue and yellow light form mutual colors and emit white light. Since this method also uses only a single LED die, its operating voltage is only 2 · 7 V lower than the 3 · 5 V of GaN LEDs, and no white light is needed to obtain white light. J M The fifth solution that can generate white light is currently under development. Ultraviolet light white LED ’The principle is to use ultraviolet light to excite three or more Cai Xing powders to emit fluorescent light, and generate white light after color mixing. Say goodbye to the first and second solutions that can produce white light. The common disadvantage is that if one of these different light-color LEDs is used at the same time, normal white light will not be obtained. Different, so more

Control circuit, resulting in higher cost, which are all unfavorable factors in practical application. The second and third schemes that can generate white light are both using complementary color to produce white light, and the continuity of its spectral wavelength distribution. It is not as good as the real sunlight ', after mixing colored light, color unevenness will appear in the visible light spectral range (40 nm ~ 700 m), resulting in lower color saturation; although humans

556365

These eyes can ignore these phenomena, and only see the detection of white high-precision optical detectors, such as photography and i, but in some of the 'color rendering is still substantially low, that is, the object color machine or Cameras have errors, so the white light source produced by this method is only human, and it will be used for lighting purposes. 5 As a simple As for the fourth solution that can generate white light, its shortcomings are only 81 m / w and its life time is only 8000 hours. In terms of practical, thinking, and luminous efficiency, it must be further broken. It is difficult to use only the layer to consider the most white light on the fluorescent conditions, and the above-mentioned color mixing principle applicable to each light energy. After that, the source was milling. One is the fluorescent material conversion of phosphor conversion, which makes Cheng Fei use five kinds of quantum efficiency materials at the same time in the deployment of five kinds of production. At the same time, three types or linear equations of three primary colors of fluorescent white light are used. High color rendering, using a variety of fluorescent excitation light, the absorption of light is also as much as possible to use the above-mentioned fluorescent powder type, that is, the proportion of light powder, the powder is so that it can not be close to these coefficients It is better to use three kinds of light materials or to change the color of the mixed material to get white or emit fluorescent light. The difference in the absorption of fluorescent powder is too large, so it is difficult to limit it greatly. In addition, the root equation is two-dimensional. It is technically two-dimensional with light. [Objective of the invention] The reason is that the light-emitting monopolar

The inventor was dedicated to research and cooperated with scientific application. With the shortcomings, he broke through the limitations of the conventional technology to reduce the problem. He proposed to use a single type of semiconductor fluorescent powder with two as the excitation light source to obtain a white light emission. Of the diode

556365 V. Description of the invention (4) Production method. As mentioned before, Bai Zhong _. ^, ^ ^ ^ ^ ^ White first composed of three primary colors of light: red, green, and blue. However, according to the principle of optical color mixing, / _ ^ ^ ^, if the human optic nerve receives two kinds of light at the same time Color Thorn > Off Raft. See M 4 ·, + e. At this time, the two light colors are called complementary colors. For example, blue-violet light with a wavelength of 4 ^ λ Λ η r7 [) rR () + to & 400 to 410 nm can be mixed with a wavelength of main and eight-Λ light to form white light. Therefore, the present invention uses a single kind of glorious powder of = color: == zinc, combined with its fluorescent diode: method. White light emitting diode as light source

Another object of the present invention, + ML #, 4g 1 ^ t is to provide a semiconductor type sulfide (zinc, cadmium) 糸 phosphor and Feng Meng 纴 ^ ^ Φ ^ ^ ^ Proportional mixing or combination, combined with an umbrella that can emit an appropriate wavelength-^ ^ η ^ ^ ^ Α The first polar body is used as the excitation light source and properly sealed. "1" was awarded a white light emitting element with excellent light emitting characteristics. Another object of the present invention is to provide a white light-emitting diode that can be made from a single powder. For white ί i ::: 利 :::, made of type phosphor with excitation light source) [(Zn, Cd) s 2 conductor type phosphor with sulfide (zinc, cadmium ions doped in the structure as a component , And use one or more of the difference between the center of the superficial well # 1, the external excitation source is excited and emits glory light, the wavelength range of the excitation source in nm can be plotted in blue and green [Detailed description of Inner Valley Xiang]杳 Committee members, 4 a female Beiyue b to further understand the characteristics of the present invention and 556365 V. Description of the invention (5) Technical content, please refer to the following about this ~ The attached picture is for reference only. BB m ≪ Bang detailed description and drawings, but the producer. 乂 is not used to limit the present invention. The present invention is related to the use of + conductor as a white light source method. The present invention refers to the combination of the main component of the light-emitting diode system is vulcanization. (Zinc, cadmium) f Conductor-type phosphors, the main ion of which is different (that is, different from the word or ore and sulfur) 'use one or such as: silver ion, copper ion or chloride ion, etc., other ion, with the exception The light source is excited by the light source and emits fluorescent light. By using an external envelope with a light emission of 2 m at an appropriate wavelength, it can be from 495_ blue-green light to 34nm UV ^. 丄:, the mixing ratio of the wavelength range phosphor and the packaging material, = U with semiconducting current It can be obtained—the jealousy with good luminous properties applies the aforementioned main chemical # 8 of the fluorescent powder, which is extremely low. Γ ΓΗ, Q Ί The pre-composition is sulfide (zinc, manganese, [(Zn, Cd) S ], This compound can form a tetragonal phase "ubi 彳 日 日 体 ,、,、 口 构" at low temperature, one is

(―); Another-C two times V: Wuertzite of hexagonal structure. It is said that the luminous efficiency of H is higher than that of the former ', which is also the reason for the preparation of such fluorescent II and subsequent calcination. Because sulfide (zinc, cadmium) is a solid crystal, it appears through the high temperature band and the energy gap between the two bands. From the band of r and conduction (zinc, weave) to long-wavelength ultraviolet light (wavelength b, as far as sulfur is concerned, the scope of light is not itself a luminescent material. Ranruo;

Page 9 is 6365 V. Description of the invention (6) Adding a small amount of foreign ions to the material Light absorbed by the outside < For example, silver ions, it is acceptable to release energy from the parent material. However: in the excited state, and then fluoresced in the form of valence: A g +) cation (such as silver ions, which is a positive ion into an appropriate amount of anion (such as; 1, j, or cadmium when the positive divalent is different, The charge must be added. At this time, the Λ lice added is negative one valence · C 1 a) to flat, and the anion used to balance the electric cations called activators is called co-living The Mi electron donation acceptance mechanism is completed; :::: Photocenter, 'By semiconductor-like' The present invention also can be used in semiconductor-type materials to form ions in sulfide (zinc, ore) polar bodies. In addition, 2 is f luminescence Source to produce white light-emitting dicadmium) structure, it can also be prepared by adding a heterogeneous ion to the vulcanization (Ci, II: two-conductor Γ compound emission spectrum; the longer the light spectrum, its color rendering will be higher than The conventional three waves are narrow ... 'This is because the single-spectrum bands constituting the latter are mostly compared to the former. The method of making the white light source of the present invention includes the selected fluorescent seven, its deployment and packaging technology, and the following are specific implementations of it. Description: 1 · Synthesis of a semiconductor type vulcanization Zn, Cd) -based phosphor, a = Zn, Cd) S: Ag +, C BU formulation. The synthesis method can use the dry synthesis method, solid-gaseous sintering method, direct reaction method and organometallic heat.

Page 10 556365 V. Description of the invention (7) '^ Decomposition method and so on. 2. Using X-ray powder diffraction to identify the purity of its crystal phase, as shown in Figure A. From this figure, it can be found that by comparison with the standard sulfur compound (JCPDS no: 7 9-2 2 0 4) in the first figure b, it can be seen that the sulfide (zinc, cadmium) phosphor of this sample is a single-phase hexagonal Crystalline structure (wur tzite) powder. 3. Measure the excitation spectrum of (Zn, Cd) s · C 1-phosphor with the wavelength of 5 54 nm as the detection point, as shown in the second figure a. From this light, this phosphor can be used as a light source from 495 nm blue-green light to 34 nm light. 4. Using ultraviolet light as the excitation source to measure the (Zn, to) S: Ag +: light emission spectrum, as shown in Figure 1B, from the spectrum, we can know that the doped silver and chloride ion sulfide (zinc) excited by external light , Record) type can produce yellow-green fluorescence. The data of this emission spectrum was converted into the chromaticity coordinates of this phosphor using the formula of the chromaticity diagram developed by the Commission for Illumination (Commission internationale del 'Eel air age, Cl E) in 1931, and A The dots are marked in the fourth figure. 5. Mix the above vulcanized (phrase, cadmium) [(Zn, Cd) S] system with epoxy resin at different weight ratios [such as vulcanized (zinc, bromide) resins 0, 0 · 1, 0 · 1 4, 0 · 1 8 and 0 _ 2 2] Then, a blue-violet light emitting diode with a main wavelength of nm is used as an excitation light source and packaged, and the spectrum is measured. From the third figure, it can be clearly found that the proportion of sequential light bodies in the spectrum 1 to 5 gradually decreases, resulting in the proportion of yellow light in the spectral structure: the first picking junction Zinc and Mingming used Wu Cai junction Ag +, I can be seen as exciting C1- Fluorescent powder represented by International Fluorescent Powder / Epoxy by Fluorescent Phosphor is 405 and then gradually changed due to fluorescent examples

Page 11 556365 V. Description of the invention (8) The result of the reduction. ^ In the chromaticity coordinate diagram, draw a line between A and β [the sulfide (the ratio of zinc and cadmium jj oxygen resin is 〇]) with a dashed line. It is found that this chromatic light mixed resonance connection can pass through the chromaticity diagram. White area. In addition, the light-color change of the spectrum obtained by mixing phosphors in different proportions in step-also conforms to the connection of the color-light mixing theory along the two points A and B. In summary, the conventional white light-emitting diodes Compared with the production method that requires the use of multiple fluorescent materials, the method of the present invention has the following advantages:

1. The present invention can emit white light only by using a single phosphor with a single light emitting diode. Therefore, the method for manufacturing the white light emitting diode of the present invention is simple and low cost, and is superior to the conventional three-wavelength white light source. 2 The energy of the semiconductor-type fluorescent material used in the present invention is largely determined by the energy band gap. Therefore, when different types of foreign ions are added as the light emitting center, they can be excited by light of the same wavelength. And emit fluorescent light of different light colors. That is, a single phosphor can emit multi-colored light. There is no conventional method to limit all phosphors to the same excitation wavelength, and it can be used in a wide range of applications.

3. The semiconductor-type fluorescent material used in the present invention can add multiple light-emitting centers of different ions in the same main structure, and can also form the result of mixing multiple light colors to form white light. The substantial effect of its spectral characteristics can be almost equal or even superior. A conventional three-wavelength white light source. 4. The semiconductor sulfide (zinc, cadmium) series fluorescent powder of the present invention can emit blue-green light with a wavelength of 495 nm to ultraviolet light with a wavelength of 340 nm

Page 12 556365

Excited by the diode, it has a wide range of applications, has high luminous efficiency, and has great industrial application value. The following is an experiment of making white light emitting diodes from ZnS-Cd phosphors: 1. Experimental description:

1. The experimental samples were fabricated into white light-emitting diodes using 5 mm Standard Lamp packaging technology, using ZnS-Cd / BAM / YAG phosphors and 405 nm / 450 nm blue wafers. 2. A total of five combinations of experimental samples are shown in the table below. The experimental group is 1, 2, 3, the control group is 4, 5, and the color adjustment is centered at (0. 30, 0. 31).

No. Description of phosphor powder wafer 1 ZnS-Cd 405 nm wafer wavelength is λ p 2 ZnS-Cd 450 nm wafer wavelength is λ d 3 ZnS-Cd + BAM 405 nm wafer wavelength is λ p 4 ZriS-Cd + YAG 405 nm wafer wavelength is λ p 5 YAG 450 nm wafer wavelength is λ d. Page 13 556365 V. Description of the invention (ίο) 2. Test data. 1. Color coordinates of experimental samples: CIE Chromaticily Diagram

-Bbct curve • (0 × Ϊ0.0.01) d.〇Snm- ^ ZnS Λ AS0nm- + ZnS a A〇Snm4ZnS + BAW (〇AOSnrn + YAG ^ BAM ❖ ^ SOnm- ^ YAG 0.2 0.25 0.3 0.35 0.4 0.45 0.5 2. Experiment Spectral chart of the sample: 2.1 · 405nm Dice + ZnS-Cd

The spectrum of 405 nm dice + ZnS Sample

6.00E-05 5.00E-05 4.00E-05 2 3.00E-05

CD

2.00E-05 1.00E-05 O.OOE ^ OO 330 430 4i30 530 580 630 680 730 780

Wavelength

Page 14 556365 V. Description of the invention (11) 2.2 2 4) Onm Dice + ZnS-Cd

The spectrum of 450 nm dice + ZnS Sample λ = 3υω-»-· υι

Wavelength 5nm Dice + ZnS-Cd + BAM The spectrum of 405 nm dice + ZnS + BAM Sample λιιωυωμϋι

Wavelength

Page 15 556365 V. Description of the invention (12)

2.4 405nm Dice + YAG + BAM

The spectrum of 405 nm dice + YAG + BAM Sample

380 430 480 530 580 630 680 730 780 2.00E-05 1.80E-05 1.60E-05 1.40E-05 Bangladesh 1.20E-05 § 1.00E-05 ^ 8.00E-0E 6.00E-06 4.00E-06 2.00E -06 0.00E4O0

Wavelength

2. 5 450nm Dice + YAG

The spectrum of 450 nm dice + YAG Sample

Wavelength

Page 16 556365 V. Explanation of the invention (13) III. Tribute analysis: 1 · According to the color coordinates of the experimental samples, all three samples of the experimental group can be adjusted to white light. In comparison, ZnS-Cd with 40 5 nm blue light chip is the best Close to the target point (0.30, 0.31), followed by ZnS-Cd with 450 nm blue wafer, and finally ZnS-Cd + BAM with 4 50 nm blue wafer. 2. According to the results of this test, ZnS-Cd can be used to produce white light with 405 ~ 450 nm blue-violet wafers.疋 The invention is in full compliance with the progressiveness of the patent application and the industrial application requirements. Therefore, if you file an application in accordance with the Patent Law, please check and approve the case in detail. = Protect the rights and interests of the inventor. Any scrutiny, please follow the instructions of the letter. The above description is only a specific embodiment of the present invention, but the present invention is: Fluorescent ;: Medium or more semiconductor type doped heteroion sulfide # 光 目 目: May = color uniformity High-brightness, high-brightness, etc. are all modified # = jik-a white light emitting diode is implemented within the scope of the following patents. 556365 Schematic description of the first picture A series of semi-cadmium] [(Zn, Cd) The first picture B series of semi-standard X-ray powder diffraction The second picture A series of semi-editing] [(Zn, Cd) The second picture B series The third picture is the use of resin mixed with diodes in different proportions and packaged into a fourth picture is the first light color change diagram.

X-ray powder diffraction pattern of conductor-type doped silver and chloride ions in sulfide (zinc, S) phosphors. Pattern of conductor-type doped silver and chloride ions in zinc sulfide. Conductor-type doped silver and chloride ions in zinc sulfide. Light-excitation spectrum of sulfide (word, S) phosphor. Conductor-type doped silver and chloride ions in sulfide (zinc, spectrum. (Zn, Cd) S: Ag +, C, phosphor powder and epoxy, Spectral change graphs measured with a blue-violet light-emitting white light source with a dominant wavelength of 40 nm. Each spectrum in the three figures is obtained by plotting the EI chromaticity coordinates.

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Claims (1)

556365 VI. Patent Application: Conductor-type fluorescent light: == light;:-A method of polar body light source, which uses a semi-fluorescent system to use the furnace π r ^ white light source, of which the semiconductor type uses 1 or ti: iso : U (Zn, Cd) s] A is the main component, which excites you and Su: /, the heart is mixed in the structure as ultraviolet light that can be taken by the external light to green to 340 nm. Two poles] light and light; 2 of the above-a kind of ion doped in the production of white light emitter; A: Conductive sulfide (zinc, cadmium) series fluorescent silver ion = silver ion, copper ion or Chloride ions, etc., with the light: Rhodium as described in-a kind of white light emission. , 彳 /, phosphor excitation source using a light-emitting diode as the most diode-light two described in the first item-a white light-emitting paste produced. ', / /, Towel phosphor excitation source can also be made by electron beam or one of the electric diodes as white light κ-gaseous sintering method, direct;: ;; using chemical synthesis method, solid placement reaction method and organic metal Prepared by thermal decomposition. For example, the scope of the patent application item 丄 a = method of bulk light source, in which semiconductor white = good white light emitting element. Light-emitting characteristics