CN101186818A - Phosphor excited by blue-violet light or blue light, manufacturing method and packaged white light diode - Google Patents

Abstract

The invention belongs to the technical field of photoelectric display materials and devices, and relates to a method for manufacturing phosphors excited by blue-violet light or blue light and white light diodes packaged with the phosphors and chips. The composition of the phosphor is Sr _3-a-b Ba _a Si _1-c O ₅ : bD, cE, dF, eG where D is divalent Eu, E is trivalent Ce, F is element B, and G is monovalent Li, a, b, c, d and e are atomic moles, and the value range is 0.0≤a≤0.2, 0.0≤b≤0.2, 0.0≤c≤0.2, 0.0≤d≤0.2, 0.0≤e≤0.2, atom The ratio c:e=1:0.01-0.1. A composite silica sol is prepared according to the composition of the phosphor, and the composite silica sol is sprayed and granulated to obtain dry gel particles, which are fired at high temperature by microwave to obtain the phosphor particles. By adopting the composition and manufacturing method of the above-mentioned phosphor, it is easy to adjust the size, shape, spectrum, brightness and luminous efficiency of the phosphor particles, and realize mass production. The phosphor particles are packaged together with blue-violet light or blue-light GaN-based chips to obtain white light diodes.

Description

Phosphor excited by blue-violet light or blue light, manufacturing method and packaged white light diode

【Technical field】

The invention belongs to the technical field of photoelectric display materials and devices, and relates to a fluorescent body excited by blue-violet light or blue light, a manufacturing method and a white light diode packaged with the fluorescent body and blue-violet light or blue light GaN-based chip.

【Background technique】

The current light-emitting mode of white light diodes is that after the current is injected, the GaN semiconductor as a chip emits blue light with a wavelength of 460 nanometers, and the blue light excites the phosphor layer with YAG:Ce ³⁺ as the main component to produce yellow light with a wavelength of 560 nanometers. Blue light combines with yellow light to form white light. GaN-based chips capable of emitting blue-violet or blue light at a wavelength of 400-460 nm have been commercially used. For solid state lighting, white light diodes with high power, high brightness and high color rendering index are required. In particular, white light diodes can be used as backlight sources for televisions, computers, and display devices. As far as phosphors are concerned, existing phosphors such as YAG:Ce ³⁺ aluminates cannot meet the requirements in terms of thermal stability, color rendering index, excitation and emission spectrum technical parameters. Rare earth-doped silicate phosphors have the advantages of good stability, low cost, wide excitation and emission spectra, and high color rendering, and have become important candidate substitutes for YAG:Ce ³⁺ . However, these phosphors, for example, Sr _3-x SiO ₅ :Eu ²⁺ _x , 0<x≤1 (CN1745159A), still have disadvantages: 1) The composition is single, and the excitation spectrum, emission spectrum, brightness and luminous efficiency are not easy Adjustment, 2) Synthesis by high-temperature solid-phase method, the composition of the phosphor is not uniform, and the size, shape and crystallinity are not easy to control. In addition, when the rare earth-doped silicate phosphor is prepared by the liquid phase method, the silicon source is usually tetraethyl orthosilicate, which is toxic and the hydrolysis conditions are unstable. Therefore, it is necessary to use a new silicate phosphor composition and a new preparation method to prepare the phosphor and package it into a white light diode with superior performance.

【Content of invention】

The purpose of the present invention is to solve the problems of the prior art, and to provide a phosphor composition excited by blue-violet light or blue light, a manufacturing method and a white light diode. Features are superior.

In order to achieve the above object, the present invention discloses a phosphor excited by blue-violet light or blue light. The composition of the phosphor is Sr _3-ab Ba _a Si _1-c O ₅ : bD, cE, dF, eG where D is di Valence Eu, E is trivalent Ce, F is element B, G is monovalent Li, a, b, c, d and e are atomic moles, and the value range is 0.0≤a≤0.2, 0.0≤b≤0.2, 0.0 ≤c≤0.2, 0.0≤d≤0.2, 0.0≤e≤0.2, atomic ratio c:e=1:0.01-0.1.

The present invention also provides a method for manufacturing a phosphor excited by blue-violet light or blue light, characterized in that the method comprises the following steps:

(1) Preparation of composite silica sol: adopt nano silicon dioxide, the purity is 99.9-99.99% by weight percentage, and the particle size is 5-10 nanometers, according to the stoichiometric composition of phosphor, adding other components by weighing; by solid: Liquid volume ratio = 1: 10-20 Add deionized water, under mechanical stirring, titrate with 30% nitric acid aqueous solution to pH = 1-3, stir for 3-6 hours to obtain composite silica sol;

(2) Spray granulation: the above composite silica sol is sprayed at a compressed air temperature of 110°C-200°C, a dry air volume of 100-200m ³ /h, and a material flow of 1-2L/h to obtain xerogel particles;

(3) Microwave high-temperature firing: pre-fire the above-mentioned dry gel particles in a box-type resistance furnace at a temperature of 600-800°C for 3-6 hours, and obtain pre-fired powder after natural cooling; The phosphor is obtained by firing in an industrial microwave oven at a temperature of 1200-1600° C. for 3-12 hours in a mixed gas of N ₂ +5% H ₂ .

White light diodes can be prepared by using the phosphors excited by blue-violet light or blue light of the present invention, which is characterized in that the phosphor particles are packaged together with blue-violet light or blue-light GaN-based chips to obtain a color rendering index of 60-80 and a color temperature of 2000- White LEDs in the 5000K range.

The advantage of the present invention is that, in the Sr ₃ SiO ₅ :Eu ²⁺ composition, various elements such as Ba, Ce, B and Li are introduced to realize the adjustment of the composition, structure and spectrum of the phosphor; Silicon is used as a silicon source to modulate composite silica sol, which replaces the ethanol hydrolysis method of tetraethyl orthosilicate, and the process is environmentally friendly and easy to control; microwave technology is used to quickly burn phosphors, which is energy-saving, environmentally friendly, and has high manufacturing efficiency; the composite sol spray method can ensure The components are mixed evenly; it is easy to obtain spherical phosphors, and the post-milling treatment of the phosphors can be eliminated; the composite sol spray-microwave high-temperature firing method is adopted, and the obtained phosphors are packaged with chips through the regulation of components and their spectral properties. , can be excited in a wide range of blue light spectrum, the color coordinates are stable, and a white light diode with excellent characteristics such as thermal stability, color rendering index, excitation and emission spectrum can be manufactured.

【Description of drawings】

1 is a schematic diagram of a process flow of a phosphor manufacturing method excited by blue-violet light or blue light;

Fig. 2 is the excitation spectrum and the emission spectrum diagram of phosphor;

Fig. 3 is a schematic diagram of the structure of a white light diode encapsulated with the prepared phosphor.

【Detailed ways】

The following will be described in detail in conjunction with the embodiments of the present invention with reference to the accompanying drawings.

According to the phosphor components provided, the present invention mainly includes several steps of compound silica sol preparation, spray granulation, and microwave high-temperature firing. in:

1) Preparation of composite silica sol

Nano-silica is used, the purity is 99.9-99.99% by weight, and the particle size is 5-10 nanometers. According to the stoichiometric ratio of the phosphor, other components are added by weighing, of which: Sr and Ba are used to analyze pure nitrate form, Eu in the form of spectroscopically pure europium nitrate, Ce in the form of spectroscopically pure _Ce2O3 with an average size of 50 nm, B in the _form of _HBO3 , and Li in the form of _LiNO3 . Then add deionized water according to solid: liquid volume ratio = 1: 10, under the condition of mechanical stirring, titrate with 30% nitric acid aqueous solution to pH = 1-3, and stir for 3-6 hours to obtain composite silica sol.

2) Spray granulation

The above composite silica sol is sprayed at a compressed air temperature of 110°C-200°C, a dry air volume of 100-200m ³ /h, and a material flow of 1-2L/h to obtain xerogel particles.

3) microwave high temperature firing

Dry gel particles are pre-fired in a box-type resistance furnace at a temperature of 600-800°C for 3-6 hours, and then naturally cooled to obtain a pre-fired powder. The calcined powder is then put into an industrial microwave oven at a firing temperature of 1200-1600° C. and fired in a mixed gas of N ₂ +5% H ₂ for 3-12 hours to obtain a phosphor.

The method for preparing a white light diode by applying the above-mentioned phosphor is:

The prepared phosphor and GaN-based semiconductor chips are used to package white light diodes. The chip emits blue-violet or blue light with a wavelength in the range of 400-480 nanometers. Under the excitation of 400-480 nm light, the phosphor produces yellow-green light with a wavelength range of 560-580 nm. The diode is packaged by a known process, the chip is placed on the reflective cup, and the chip and the phosphor are molded by transparent epoxy resin. The diode emits white light, the color rendering index is above 80, and the color temperature is in the range of 2000-5000K.

The following examples are intended to further illustrate the process characteristics of the present invention without limiting the present invention.

Example 1

According to the composition of the phosphor and the process flow of accompanying drawing 1, take a=0.0, b=0.05, c=0.0, d=0.0, e=0.0, take by weighing analytically pure strontium nitrate, the purity is 99.9%, and the average size is 10 Nano SiO ₂ and spectroscopically pure europium nitrate were placed together in a beaker. According to solid: liquid volume ratio = 1: 10, add deionized water, mechanically stir, titrate to pH = 1 with 30% nitric acid aqueous solution, and stir for 3 hours to obtain a composite silica sol. The composite silica sol is sprayed and granulated, and the compressed air temperature is set at an inlet temperature of 110°C, the dry air volume is 100m ³ /h, and the material flow is 1L/h to obtain xerogel particles; the xerogel particles are put into a corundum crucible, Pre-fire in an ordinary muffle furnace at a temperature of 600°C for 3 hours, and then naturally cool to obtain a pre-fired powder. Place the crucible with the pre-burned powder in an industrial microwave oven, first pass in a mixed gas of N ₂ +5% H ₂ (volume ratio) with a flow rate of 2L/h, control the temperature at 1200°C for 3 hours, and then close the Turn off the power, and cool down to obtain phosphor particles.

The fluorescent particles and a commercial blue-violet light chip with an emission wavelength of 400 nanometers with a bracket are encapsulated with epoxy resin to obtain a white light diode. Figure 2 is the fluorescence of the composition Sr _3-ab Ba _a Si _1-c O ₅ :bEu ²⁺ , cE, dF, eG (a=0.0, b=0.05, c=0.0, d=0.0, e=0.0) Figure 3 is a schematic diagram of the structure of a packaged white light diode. In the figure: a GaN-based semiconductor chip 1 is placed on a reflective cup 2, and the chip and the phosphor 3 are formed by transparent epoxy resin 4. E: LED chip emits blue light, F: phosphor emits yellow-green light.

Example 2

According to the composition of phosphor and the technological process of accompanying drawing 1, get a=0.1, b=0.1, c=0.05, d=0.0, c: e=10: 1, take by weighing analytically pure strontium nitrate and barium nitrate, purity 99.9% SiO ₂ with an average size of 10 nm and spectrally pure Ce ₂ O ₃ with an average size of 50 nm, analytically pure lithium nitrate and spectroscopically pure europium nitrate were put together in a beaker. According to solid: liquid volume ratio = 1: 15, add deionized water, mechanically stir, titrate to pH = 2 with 30% nitric acid aqueous solution, and stir for 5 hours to obtain a composite silica sol. The composite silica sol is sprayed and granulated, and the compressed air temperature is set as the inlet temperature of 150°C, the dry air volume is 150m ³ /h, and the material flow is 2L/h to obtain xerogel particles; the xerogel particles are put into a corundum crucible, and Pre-fired in a common muffle furnace at a temperature of 700°C for 4 hours, and obtained the pre-fired powder after natural cooling. Place the crucible with the pre-burned powder in an industrial microwave oven, first pass in a mixed gas of N ₂ +5% H ₂ (volume ratio) with a flow rate of 2L/h, control the temperature at 1300°C for 6 hours, and then close the Turn off the power, cool to obtain spherical phosphor particles. The fluorescent particles and the commercial blue light chip with the emission wavelength of 460 nanometers and the support are packaged with epoxy resin to obtain a white light diode.

Example 3

According to the composition of phosphor and the technological process of accompanying drawing 1, get a=0.0, b=0.0, c=0.1, d=0.0, c: e=1: 0.05, take by weighing analytically pure strontium nitrate, purity is 99.9% SiO ₂ with an average size of 10 nm, spectroscopically pure Ce ₂ O ₃ with an average size of 50 nm, and analytically pure lithium nitrate were put together in a beaker. According to solid: liquid volume ratio = 1: 20, add deionized water, mechanically stir, titrate to pH = 3 with 30% nitric acid aqueous solution, and stir for 6 hours to obtain a composite silica sol. The composite silica sol is sprayed and granulated, and the compressed air temperature is set at an inlet temperature of 200°C, the dry air volume is 200m ³ /h, and the material flow is 1.5L/h to obtain xerogel particles; the xerogel particles are put into a corundum crucible , pre-fired in an ordinary muffle furnace at a temperature of 800 ° C for 6 hours, and obtained pre-fired powder after natural cooling. Place the crucible with the pre-burned powder in an industrial microwave oven, first feed the mixed gas of N ₂ +5% H ₂ (volume ratio) with a flow rate of 3L/h, control the temperature at 1400°C for 12 hours, and then close the Turn off the power, cool to obtain spherical phosphor particles. The fluorescent particles and the commercial blue light chip with the emission wavelength of 460 nanometers and the support are packaged with epoxy resin to obtain a white light diode.

Claims (5)

1. royal purple light or blue-light excited fluor, the composition that it is characterized in that described fluor is Sr _3-a-bBa _aSi _1-cO ₅: bD, cE, dF, eG, D is divalence Eu in the formula, E is trivalent Ce, and F is an element B, and G is monovalence Li, and a, b, c, d and e are the atomic molar number, and numerical range is 0.0≤a≤0.2,0.0≤b≤0.2,0.0≤c≤0.2,0.0≤d≤0.2,0.0≤e≤0.2, atomic ratio c: e=1: 0.01-0.1.

2. the manufacture method of the royal purple light of a claim 1 or blue-light excited fluor is characterized in that said method comprising the steps of:

(1) preparation comprehensive silicon colloidal sol: adopt nano silicon, purity is 99.9-99.99% by percent by weight, and granularity is the 5-10 nanometer, and according to the stoichiometric ratio composition of fluor, weighing adds other composition; By solid: liquid volume ratio=1: 10-20 adds deionized water, under mechanical stirring, is that 30% aqueous nitric acid is titrated to pH=1-3 with concentration, churning time 3-6 hour, obtains comprehensive silicon colloidal sol;

(2) mist projection granulating: above-mentioned comprehensive silicon colloidal sol is at 110 ℃～200 ℃ of compressed air temperature, dry air amount 100～200m ³/ h sprays under streams 1～2L/h, obtains dry gel particle;

(3) microwave high-temperature burns till: with the pre-burning in chamber type electric resistance furnace of above-mentioned dry gel particle, temperature 600-800 ℃, time 3-6 hour, obtain the pre-burning powder behind the naturally cooling; This pre-burning powder is put into industrial microwave oven again at N ₂+ 5%H ₂In the mixed gas, under temperature 1200-1600 ℃, burnt till 3-12 hour, obtain fluor.

3. the manufacturing of royal purple light according to claim 2 or blue-light excited fluor is characterized in that described Sr and Ba with analytically pure nitrate form, and Eu is with specpure europium nitrate form, and Ce is the spectroscopically pure Ce of 50 nanometers with mean size ₂O ₃Form, B is with HBO ₃Form, Li is with LiNO ₃Form adds preparation comprehensive silicon colloidal sol.

4. an application rights requires the white light-emitting diodes of 1 described royal purple light or blue-light excited phosphor preparation, it is characterized in that encapsulating with royal purple light or blue light GaN base chip with described phosphor particle, obtain colour rendering index at 60-80, colour temperature is at the white light-emitting diodes of 2000-5000K scope.

5. the white light-emitting diodes of royal purple light according to claim 4 or blue-light excited phosphor preparation, it is characterized in that described chip emission royal purple or blue light, wavelength is in the 400-480 nanometer range, fluor is under the optical excitation of 400-480 nanometer at wavelength, produce yellow-green light, wavelength region is the 560-580 nanometer.