CN202996898U

CN202996898U - White light LED chip

Info

Publication number: CN202996898U
Application number: CN 201220555539
Authority: CN
Inventors: 曹永革; 邓著光; 陈东川; 邓种华; 兰海
Original assignee: Fujian Institute of Research on the Structure of Matter of CAS
Current assignee: Fujian Institute of Research on the Structure of Matter of CAS
Priority date: 2012-10-24
Filing date: 2012-10-24
Publication date: 2013-06-12
Anticipated expiration: 2022-10-24

Abstract

The utility model discloses a white light LED chip. The white light LED chip comprises blue light or ultraviolet LED chips in vertical structure and fluorescent ceramics covered on the chips. In the structure, the fluorescent ceramics is directly covered on the vertical structural blue light or ultraviolet LED chips, so as to form the white light LED chip, thereby preventing use of fluorescent powders in a packaging step and preventing white light LED light source high-temperature color-temperature drift caused by the fluorescent powders. Stability and lighting effect of the white light LED light source is improved.

Description

A kind of White-light LED chip

Technical field

The utility model relates to LED luminescence technology field, relates in particular to a kind of White-light LED chip structure.

Background technology

LED is as a kind of new type light source, due to have energy-saving and environmental protection, the life-span is long, toggle speed is fast, can control luminescent spectrum and forbid making the unrivaled advantage of the more high conventional light source of colorfulness obtain unprecedented development with the size of width.

Generally speaking, the acquisition of traditional white LED light source is to obtain white light by the optical excitation fluorescent material that blue light or ultraviolet LED chip send.But for common blue light or ultraviolet LED chip, its photoelectric conversion efficiency is generally lower than 30%, even present best LED chip, its photoelectric conversion efficiency can be higher than 50% yet.Therefore LED will supervene a large amount of heat when luminous.General around the chip of lighting, temperature can arrive 150 degrees centigrade to 200 degrees centigrade.Such temperature will cause the decrease in efficiency 20-30% of fluorescent material, thereby produce the colour temperature of light source and the skew of chromaticity coordinates.The light efficiency and stability of LED light source have also been affected simultaneously.

The utility model content

The utility model is intended to solve the foregoing problems of prior art, and provides a kind of simple in structure, and the White-light LED chip structure of the high and dependable performance of light efficiency is both and has simplified the use of fluorescent material in the packaging process.This White-light LED chip structure adopts blue light or ultraviolet LED chip light emitting fluorescence excitation pottery, produces white light, and described White-light LED chip is made of vertical stratification blue light or ultraviolet LED chip and the fluorescence ceramics that is covered in the chip top.

The emission spectrum of described vertical stratification blue light or ultraviolet LED chip is peak wavelength at the visible light of 400-500nm or the peak wavelength ultraviolet light at 250-400nm.

Have aperture on described fluorescence ceramics, aperture aligns with the electrode position of vertical structure LED.

The utility model directly applies to blue light or ultraviolet LED chip with the fluorescence ceramics material, has realized directly transmitting white of LED chip by directly cover the fluorescence ceramics material on LED chip.Avoid the use of fluorescent material in follow-up LED packaging technology, thereby effectively avoided because the fluorescent material quantum efficiency that high temperature causes descends, the colour temperature of light source the chromaticity coordinates drift.Contrast shows the 5W white LED light source of same COB encapsulation by experiment, the light source igniting of using fluorescent material after 30 minutes luminous flux drop to 75% of initial value, colour temperature is elevated to 6572K by 6021K simultaneously.And this White-light LED chip light source igniting after 30 minutes its luminous flux be 97% of initial value, and colour temperature does not change substantially.The luminous efficiency of source of using simultaneously fluorescent material under similarity condition is 150lm/W, and the luminous efficiency of source of the LED chip of application fluorescence ceramics can reach 215lm/W.Can embody by the contrast under above same experiment condition the clear superiority of using fluorescence ceramics.Realize simultaneously the emission of white light in the LED chip level, simplified the proportioning process of fluorescent material in the LED packaging technology, made the colour temperature consistency of the LED light source of production be greatly improved.

Description of drawings

Fig. 1 is the White-light LED chip structural representation.

Fig. 2 is the XRD collection of illustrative plates of fluorescence ceramics sample in embodiment 1.

Fig. 3 is the white light LEDs spectrogram in embodiment 1.

Fig. 4 is the XRD collection of illustrative plates of fluorescence ceramics sample in embodiment 2.

Fig. 5 is the white light LEDs spectrogram in embodiment 2.

Fig. 6 is the XRD collection of illustrative plates of fluorescence ceramics sample in embodiment 3.

Fig. 7 is the white light LEDs spectrogram in embodiment 3.

Fig. 8 is the XRD collection of illustrative plates of fluorescence ceramics sample in embodiment 4.

Fig. 9 is the white light LEDs spectrogram in embodiment 4.

Embodiment

Example 1 is with the Ce of 0.01wt.% ₂O ₃Powder mixes in the YAG powder, fully mixes by wet ball grinding, the dry rear fluorescence ceramics powder material that obtains.With the fluorescence ceramics powder material by cold isostatic compaction be slightly larger in diameter in the idiosome of 4 inches, utilize simultaneously masterplate to reserve micropore to aim at the top electrode of blue-light LED chip on ceramic idiosome.Idiosome is put into the vacuum high-temperature sintering stove, and sintering temperature is 1450 ^oC, sintering time 10 hours.Fig. 2 is the XRD collection of illustrative plates after this Ce:YAG fluorescence ceramics sintering, and each peak position in figure all matches with the standard peak position of YAG phase, and assorted peak, illustrates that this sample has changed the YAG phase into fully through this sintering process.The sample that sintering is completed is through surface finish and to be thinned to thickness be 0.7mm.This Ce:YAG fluorescence ceramics sheet is aimed at and is covered on 4 inches vertical stratification blue-ray LED wafers that step fabrication completes, and utilize photoresist to be mask, utilize electron beam evaporation to realize the upper metal electrode of chip on the LED wafer of fluorescence ceramics being covered with.And utilize laser cutting to be LED chip the white light LEDs wafer that this preparation is completed.As shown in Figure 1, the White-light LED chip structural representation that Fig. 1 completes for preparation, in figure, 20 for peak wavelength is the 450nmLED chip, and this chip structure adopts successively growing n-type GaN layer 24 of MOCVD method, GaN quantum well 23 and P type GaN layer 22 for sinking to the bottom at sapphire on 25.Be coated with the fluorescence ceramics sheet 10 with micropore on the P of LED chip type GaN layer 22, simultaneously be coated with P type metal electrode 21 at the micropore place.The photoelectricity test result of this White-light LED chip is: colour temperature is Tc=5530K, color rendering index Ra=62.4, light efficiency η=175lm/W.The spectrogram of its test as shown in Figure 3.

Example 2 is with the Ce of 0.1wt.% ₂O ₃Powder mixes in the YAG powder, fully mixes by wet ball grinding, the dry rear fluorescence ceramics powder material that obtains.Be that slightly larger in diameter is in the idiosome of 4 inches with the fluorescence ceramics powder material by cold isostatic compaction.Idiosome is put into the vacuum high-temperature sintering stove, and sintering temperature is 1450 ^oC, sintering time 10 hours.Fig. 4 is the XRD collection of illustrative plates after this Ce:YAG fluorescence ceramics sintering, and each peak position in figure all matches with the standard peak position of YAG phase, and assorted peak, illustrates that this sample has changed the YAG phase into fully through this sintering process.The sample that sintering is completed is through surface finish and to be thinned to thickness be 0.7mm.This Ce:YAG fluorescence ceramics sheet is used method same as Example 1 be prepared into White-light LED chip.The photoelectricity test result of this White-light LED chip is: colour temperature is Tc=6423K, color rendering index Ra=60.5, light efficiency η=231lm/W.The spectrogram of its test such as accompanying drawing 5 show.

Example 3 is respectively with the Ce of 0.1wt.% ₂O ₃Sm with 0.08wt.% ₂O ₃Powder mixes in the YAG powder, fully mixes by wet ball grinding, the dry rear fluorescence ceramics powder material that obtains.Be that slightly larger in diameter is in the idiosome of 4 inches with the fluorescence ceramics powder material by cold isostatic compaction.Idiosome is put into the vacuum high-temperature sintering stove, and sintering temperature is 1600 ^oC, sintering time 10 hours.XRD collection of illustrative plates after this Ce:Sm:YAG fluorescence ceramics sintering of Fig. 6, each peak position in figure all match with the standard peak position of YAG phase, and assorted peak, illustrate that this sample has changed the YAG phase into fully through this sintering process.The sample that sintering is completed is through surface finish and to be thinned to thickness be 0.5mm.The YAG fluorescence ceramics sheet that this Ce and Sm are mixed is altogether used method same as Example 1 and is prepared into White-light LED chip.The photoelectricity test result of this White-light LED chip is: colour temperature is Tc=4228K, color rendering index Ra=71.3, light efficiency η=163lm/W.The spectrogram of its test such as accompanying drawing 7 show.

Example 4 is respectively with the Ce of 0.1wt.% ₂O ₃, 0.5wt.% Eu ₂O ₃And the Yb of 12wt.% ₂O ₃Powder mixes in the YAG powder, fully mixes by wet ball grinding, the dry rear fluorescence ceramics powder material that obtains.Be that slightly larger in diameter is in the idiosome of 4 inches with the fluorescence ceramics powder material by cold isostatic compaction.Idiosome is put into the vacuum high-temperature sintering stove, and sintering temperature is 1600 ^oC, sintering time 10 hours.XRD collection of illustrative plates after this Ce:Eu:Yb:YAG fluorescence ceramics sintering of Fig. 8, each peak position in figure all match with the standard peak position of YAG phase, and assorted peak, illustrate that this sample has changed the YAG phase into fully through this sintering process.The sample that sintering is completed is through surface finish and to be thinned to thickness be 0.7mm.The YAG fluorescence ceramics that this Ce, Eu and Yb are mixed is altogether used method same as Example 1 and is prepared into White-light LED chip.The photoelectricity test result of this White-light LED chip is: colour temperature is Tc=3476K, color rendering index Ra=87.5, light efficiency η=146lm/W.The spectrogram of its test as shown in Figure 9.

Foregoing is four specific embodiments of the present utility model, and be not limitation of the utility model, any trickle modification, equivalent variations and modification that every foundation technical spirit of the present utility model is done top embodiment all still belong to technology contents of the present invention and scope.

Claims

1. White-light LED chip adopts blue light or ultraviolet LED chip light emitting fluorescence excitation pottery, produces white light, it is characterized in that: this White-light LED chip is made of vertical stratification blue light or ultraviolet LED chip and the fluorescence ceramics that is covered in the chip top.

2. White-light LED chip according to claim 1 is characterized in that: the emission spectrum of described vertical stratification blue light or ultraviolet LED chip is peak wavelength at the visible light of 400-500nm or the peak wavelength ultraviolet light at 250-400nm.

3. White-light LED chip according to claim 1, it is characterized in that: have aperture on described fluorescence ceramics, aperture aligns with the electrode position of vertical structure LED.