CN201584433U - Efficient anti-interference LED chip - Google Patents

Abstract

The utility model discloses an efficient anti-interference LED chip, which belongs to the technical field of LED chips, and solves the problem to achieve the purpose of arrangement of double layers of membrane capable of improving the LED light-extraction efficiency and preventing the interference light on the current LED chip. The utility model adopts a technical scheme that a first layer of membrane and a second layer of membrane are coated on the surface of the efficient anti-interference LED chip from bottom to top, wherein the first layer of membrane adopts a blue light full permeable membrane made of TiO2s, the second layer of membrane adopts a yellow light reflective membrane made of ZnS-MgF or the blue light full permeable membrane made of TiO2as, and the whole thickness of the first and the second layers of membrane is one quarter of blue light wave length. The utility model can be applied extensively in the field of the LED chips for lighting.

Description

High-efficiency anti-interference LED chip

Technical field

The utility model high-efficiency anti-interference LED chip belongs to the led chip technical field.

Background technology

The semiconductor lighting industry is risen in the whole world.In country's medium-term and long-term program for the development of science and technology strategy investigation meeting, " new century illuminating engineering " is recommended as major project, development semiconductor lighting engineering is to the new period.Light efficiency 100～the 1201m/W of power type white light LED enters general illumination market and really can replace incandescent lamp and fluorescent lamp now, and its light efficiency is still waiting to improve.This requires to improve constantly the quantum efficiency of LED on the one hand in the making of chip, also require simultaneously to improve light extraction efficiency in the process as far as possible encapsulation and the designing and producing of light fixture of LED.One of reason that existing LED light extraction efficiency is low is, the refractive index of led chip is higher, and the light that LED sends has quite a few light by the boundary reflection of chip with extraneous (epoxy resin) in the outgoing chip, therefore cause the loss of led chip light.Blue chip excites yellow fluorescent powder to make fluorescent material send gold-tinted, and chip absorbs the gold-tinted photon, can make chip send veiling glare.

The utility model content

In order to overcome the deficiency that prior art exists, problem to be solved in the utility model is: existing led chip is provided with the bilayer film that can improve the LED light extraction efficiency and prevent stray light.

In order to address the above problem, the scheme that the utility model adopts is: high-efficiency anti-interference LED chip is coated with ground floor film and second layer film from bottom to top on the surface of described led chip;

Described ground floor film is that material is TiO ₂The blue light full-trans-parent film;

Described second layer film is that material is the gold-tinted reflectance coating of ZnS-MgF, or material is TiO ₂The blue light full-trans-parent film.

The gross thickness of above-mentioned ground floor film and second layer film is 1/4th of a blue light wavelength.

Be coated with ground floor film and second layer film on LED of the present utility model, film can reduce the reflection of blue light when led chip sends, and improves the light extraction efficiency of led chip; And preventing that the gold-tinted that fluorescent material sends from entering chip, plating one deck is to the gold-tinted total reflection film.

Its basic principle is: led chip material refractive index is very high, reaches 3.6 in the visible light refractive index, and as the direct outgoing of light that fruit chip sends, then owing to boundary reflection, the luminous energy of loss has:

$R={\left(\frac{3.6-1}{3.6+1}\right)}^2=31.9\%;$

The LED structure of prior art be in led chip outside with the silica gel encapsulation, but this way still can allow 20% optical energy loss, result of calculation is as follows:

Interface one: silica gel, led chip;

The refractive index of silica gel is 1.54 at visible light, so the reflectivity at this interface is: $R={\left(\frac{3.6-1.54}{3.6+1.54}\right)}^2=16\%;$

Interface two: silica gel, air;

$R={\left(\frac{1.54-1}{1.54+1}\right)}^2=4.7\%;$

Therefore, the light that led chip sends through two boundary reflections after, light intensity becomes

T ₁＝(1-16％)(1-4.7％)＝80.05％

The utility model can plate two-layer TiO outside led chip ₂Film, (optical thickness is 1/4th times of blue light wavelength to blue light; Making certain thickness film concerning gold-tinted makes gold-tinted pass through film all to reflect no transmits yellow.And very high to the blue light transmissivity), and then add the silica gel encapsulation.After the utility model processing, the LED light extraction efficiency can improve 9%.Carry out the calculating of this structured light transmissive rate below.

Interface one: TiO ₂, led chip;

TiO ₂Refractive index be 2.2 at visible light, so the reflection coefficient during the blue light outgoing of this interface is

$R={\left(\frac{3.6-2.2}{3.6+2.2}\right)}^2=5.8\%;$

Interface two: silica gel, TiO ₂This interface to the reflection coefficient of blue light is

$R={\left(\frac{2.2-1.54}{2.2+1.54}\right)}^2=3.1\%;$

Interface three: silica gel, air; This interface to the reflection coefficient of blue light is

$R={\left(\frac{1.54-1}{1+1.54}\right)}^2=4.5\%;$

Therefore, the light that led chip sends through three boundary reflections after, light intensity becomes

T ₂＝(1-5.8％)(1-3.1％)(1-4.5％)＝87.7％

As seen, through plated film on led chip, the more existing structure of light extraction efficiency has improved

(T ₂-T ₁)/T ₁＝8.9％≈9％

The technical solution of the utility model is a kind of film of design, is coated with this film on led chip, encapsulates the light extraction efficiency that can make LED then and improves about 9%.

Description of drawings

Below in conjunction with accompanying drawing the utility model is described further

Fig. 1 is the structural representation of the utility model high-efficiency anti-interference LED chip.

Wherein 1 is led chip, and 2 is the ground floor film, and 3 is second layer film, and 4 is the blue light full-trans-parent film, and 5 is the gold-tinted reflectance coating.

Embodiment

High-efficiency anti-interference LED chip as shown in Figure 1 is coated with ground floor film 2 and second layer film 3 from bottom to top on the surface of described led chip 1; Described ground floor film 2 is that material is TiO ₂Blue light full-trans-parent film 4; Described second layer film 3 is that material is the gold-tinted reflectance coating 5 of ZnS-MgF, and the gross thickness of ground floor film 2 and second layer film 3 is 1/4th of a blue light wavelength.

Above-mentioned second layer film 3 can also be TiO with material ₂Blue light full-trans-parent film 4 substitute materials be the gold-tinted reflectance coating 5 of ZnS-MgF.

The preparation method of high-efficiency anti-interference LED chip is: the first step cleans up led chip 1; Second step, led chip 1 is put into coating machine, put into TiO ₂Target and ZnS-MgF target; In the 3rd step, be evacuated to 2 * 10 ^-2Pa, the beginning evaporation; In the 4th step, use optical monitor, first evaporation TiO ₂Film, evaporation ZnS-MgF film treats that led chip 1 upper film gross thickness arrives when requiring again, closes baffle plate, stops evaporation.

Above-mentioned evaporation coating method is taked electron gun evaporation deposit film method.That can put among the above-mentioned preparation method all is TiO ₂Target, the two-layer TiO of evaporation ₂Film.

Claims (2)

1. high-efficiency anti-interference LED chip is characterized in that: be coated with ground floor film (2) and second layer film (3) from bottom to top on the surface of described led chip (1);

Described ground floor film (2) is that material is TiO ₂Blue light full-trans-parent film (4);

Described second layer film (3) is that material is the gold-tinted reflectance coating (5) of ZnS-MgF, or material is TiO ₂Blue light full-trans-parent film (4).

2. high-efficiency anti-interference LED chip according to claim 1 is characterized in that: the gross thickness of ground floor film (2) and second layer film (3) is 1/4th of a blue light wavelength.

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