CN103515367B - Light emitting diode packaging structure - Google Patents

Abstract

A light-emitting diode packaging structure comprises a substrate, an electrode arranged on the substrate, a reflecting cup, a light-emitting element and a packaging body, wherein a stop block positioned at the bottom of the reflecting cup is formed on the substrate, the stop block divides the bottom space of the reflecting cup into a first containing part and a second containing part which are not communicated with each other, the light-emitting element comprises a first light-emitting diode crystal grain arranged in the first containing part and a second light-emitting diode crystal grain arranged in the second containing part, the light-emitting wavelength of the first light-emitting diode crystal grain is smaller than that of the second light-emitting diode crystal grain, the first containing part is filled with cycloaliphatics epoxy resin, and the second containing part and the top space of the reflecting cup are filled with bisphenol A epoxy resin. The light emitting diode packaging structure can give consideration to good light emitting performance and lower manufacturing cost.

Description

Light-emitting diode packaging structure

technical field

The invention relates to a semiconductor structure, in particular to a light emitting diode packaging structure.

Background technique

Compared with traditional light sources, light emitting diodes (Light Emitting Diode, LED) have the advantages of light weight, small size, low pollution, long life, etc. As a new type of light source, it has been increasingly used in In various fields, such as street lights, traffic lights, signal lights, spotlights and decorative lights.

Existing LED packaging structures generally include a substrate, electrodes on the substrate, LED chips carried on the substrate and electrically connected to the electrodes, and a package covering the LED chips on the substrate. In the packaging process of the light emitting diode, in order to reduce the cost, the low cost bisphenol A epoxy resin is usually used to cover the light emitting diode chip as the packaging body. However, after being directly irradiated by short-wavelength (below 500 nm) light beams, bisphenol-A epoxy resins are highly susceptible to denaturation, resulting in a decrease in light transmittance, which ultimately affects the light extraction performance of the LED packaging structure and reduces the cost. The light-emitting performance of the light-emitting diode package that is affected.

Contents of the invention

In view of this, it is necessary to provide a light emitting diode packaging structure that can balance the manufacturing cost and light extraction performance.

A light-emitting diode packaging structure, including a substrate, an electrode arranged on the upper surface of the substrate, and a reflective cup, a light-emitting element arranged in the reflective cup and electrically connected to the electrode, and a packaging body filled in the reflective cup to cover the light-emitting diode crystal grain , the upper surface of the substrate is formed with a stopper at the bottom of the reflective cup, the stopper divides the space at the bottom of the reflective cup into a first accommodating portion and a second accommodating portion that are not communicated with each other, and the light-emitting element includes a The first light emitting diode crystal grain in the housing part and the second light emitting diode crystal grain arranged in the second housing part, the wavelength of the first light emitting diode crystal grain is smaller than the wavelength of the second light emitting diode crystal grain, and the first housing part is filled with The first package body, the head space of the second receiving part and the reflection cup are all filled with a second package body, the material of the first package body is cycloaliphatic epoxy resin, and the material of the second package body is double Phenol A epoxy resin.

This kind of light-emitting diode packaging structure uses cycloaliphatic epoxy resin that is resistant to high temperature and short-wavelength light to cover the first light-emitting diode crystal grain with a shorter light-emitting wavelength, and uses bisphenol A epoxy resin with lower cost to cover the first light-emitting diode crystal grain. The second light-emitting diode crystal grain with a longer emission wavelength and the cycloaliphatic epoxy resin can effectively avoid being damaged by the first light-emitting diode crystal grain because the cycloaliphatic epoxy resin is not easy to be denatured by the irradiation of short-wavelength light beams. Denatured by direct exposure to short-wavelength light, thereby avoiding a decrease in light transmittance. In addition, bisphenol-A epoxy resins are not easily denatured by long-wavelength light beams, so bisphenol-A epoxy resins will not be affected by the second The denaturation caused by the light beam irradiation of the light-emitting diode crystal grains leads to a decrease in light transmittance, which reduces the cost under the premise of ensuring the light transmittance performance.

The present invention will be further described below in conjunction with specific embodiments with reference to the accompanying drawings.

Description of drawings

FIG. 1 is a top view of a light emitting diode package structure according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of the LED package structure along II-II shown in FIG. 1 .

FIG. 3 is a schematic diagram of a disassembled structure of the light emitting diode package structure shown in FIG. 1 .

FIG. 4 is a top view of a light emitting diode package structure according to a second embodiment of the present invention.

FIG. 5 is a cross-sectional view of the LED packaging structure along V-V shown in FIG. 4 .

Description of main component symbols

Light-emitting diode packaging structure 10, 20 Substrate 11 Bearing surface 110 bottom surface 112 side 114 Stoppers 116 electrode 12 first electrode 121 second electrode 122 third electrode 123 fourth electrode 124 reflector cup 13 containment space 130 to open 132 bottom space 134 headspace 136 First Containment Unit 1340 Second Containment Unit 1342 LED Die 14, 24 first light emitting diode die 140 Second LED Die 142 third light emitting diode die 144 Package 15 first package 150 second package 152

The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings.

detailed description

Referring to FIG. 1 , FIG. 2 and FIG. 3 , the LED package structure 10 provided by the first embodiment of the present invention includes a substrate 11 , electrodes 12 , reflective cups 13 , LED die 14 and a package body 15 .

The substrate 11 is an insulating substrate, and its material can be insulating materials such as sapphire (Sapphire) and silicon carbide (SiC). The substrate 11 includes a carrying surface 110 (i.e., the upper surface of the substrate 11 shown in FIG. 1 ), a bottom surface 112 opposite to the carrying surface 110, a side surface 114 between the carrying surface 110 and the bottom surface 112 and connecting the carrying surface 110 and the bottom surface 112 , and a stopper 116 protruding from the carrying surface 110 toward a direction away from the bottom surface 112 . The stopper 116 is located at the bottom of the reflection cup 13 . Preferably, the size of the stopper 116 gradually decreases from the carrying surface 110 in a direction away from the carrying surface 110 and the bottom surface 112 , so that the stopper 116 has an inclined side to assist the reflector cup 13 in light correction. In this embodiment, the section of the block 116 is a non-right-angled trapezoid.

The electrodes 12 are disposed on the carrying surface 110 of the substrate 11 to provide electrical connection to the LED die 14 . The electrodes 12 include a first electrode 121 , a second electrode 122 , a third electrode 123 and a fourth electrode 124 . The first electrode 121 , the second electrode 122 , the third electrode 123 and the fourth electrode 124 respectively extend from the carrying surface 110 of the substrate 11 across the side surface 114 of the substrate 11 , and finally extend to the bottom surface 112 of the substrate 11 .

The reflection cup 13 is disposed on the carrying surface 110 of the substrate 11 and partially covers the carrying surface 110 and the electrodes 12 on the carrying surface 110 . The reflective cup 13 defines a receiving space 130 , and an opening 132 is formed on a side of the reflective cup 13 away from the substrate 11 . The plane where the top of the stopper 116 is located (described by the dotted line in the figure) divides the accommodating space 130 into two parts, the bottom space 134 and the top space 136, and the stopper 116 separates the bottom space 134 of the reflective cup 13 into two parts. The first receiving portion 1340 and the second receiving portion 1342 are not connected. The first electrode 121 and the second electrode 122 are located in the first housing portion 1340 , and the third electrode 123 and the fourth electrode 124 are located in the second housing portion 1342 .

In this embodiment, the opening 132 is substantially oval. In order to adjust the direction of light emission, in this embodiment, the inner wall of the reflective cup 13 is set in an inclined shape, so that the size of the receiving space 130 gradually decreases from the opening 132 towards the direction of the substrate 11, that is, the receiving space 130 presents an inverted truncated cone. Of course, the inner wall of the reflection cup 13 can also be designed into other shapes according to actual needs and is not limited thereto.

The LED die 14 is disposed in the reflective cup 13 and electrically connected to the electrode 12 . The LED die 14 includes a first LED die 140 disposed in the first receiving portion 1340 and a second LED die 142 disposed in the second receiving portion 1342 .

The first LED die 140 is disposed on the first electrode 121 and electrically connected to the first electrode 121 and the second electrode 122 . The second LED die 142 is disposed on the third electrode 123 and electrically connected to the third electrode 123 and the fourth electrode 124 . The emission wavelength of the first LED die 140 is smaller than the emission wavelength of the second LED die 142 . In this embodiment, the first LED die 140 is a blue LED die, and the second LED die 142 is a red LED die. Furthermore, the first LED grain 140 may be a blue LED grain with a light emitting wavelength of about 450 nanometers, and the second LED grain 142 may be a red light emitting diode grain with a light emitting wavelength of about 630 nanometers. .

The package body 15 is disposed in the reflective cup 13 to cover the LED die 14 . The package 15 includes a first package 150 and a second package 152 . The first package body 150 is filled in the first receiving portion 1340 and its material is cycloaliphatic epoxy resin. The second package body 152 is filled in the second receiving portion 1342 and the head space 136 of the reflective cup, and its material is bisphenol A epoxy resin.

This kind of LED packaging structure 10 uses cycloaliphatic epoxy resin resistant to high temperature and short-wavelength light to cover the first light-emitting diode crystal grain 140 with a shorter light-emitting wavelength, and bisphenol A epoxy resin to cover the first light-emitting diode crystal grain 140 with a shorter light-emitting wavelength. The advantage of the long second light-emitting diode crystal grain 142 and the cycloaliphatic epoxy resin is that the cycloaliphatic epoxy resin is not easy to denature due to the irradiation of short-wavelength light beams, thereby effectively avoiding being damaged by the first light-emitting diode crystal grain. 140 short-wavelength light is directly irradiated and denatured to avoid a decrease in light transmittance; bisphenol-A epoxy resins are not easily denatured by long-wavelength light beams, so bisphenol-A epoxy resins will not be affected by the second light-emitting diode The denaturation of the grain 142 caused by the light beam irradiation leads to a decrease in light transmittance; the cost of bisphenol A epoxy resin is low, and the part of the reflective cup that is not filled with cycloaliphatic epoxy resin is filled with bisphenol A epoxy resin. The resin can reduce the cost to a certain extent on the premise of ensuring the light extraction performance. It should be noted that although short-wavelength light will eventually reach the bisphenol A epoxy resin above the first LED die 140 , due to the bisphenol A epoxy resin above the first LED die 140 There is a cycloaliphatic epoxy resin between the first light-emitting diode crystal grain 140, so that the first light-emitting diode crystal grain 140 is far away from the bisphenol A epoxy resin above it, and this part of bisphenol A The bisphenol-A epoxy resin will not be directly irradiated by short-wavelength light beams, which greatly delays its denaturation process and prevents the denaturation of the bisphenol A-based epoxy resin during the service life of the LED packaging structure 10 .

In addition, in view of the fact that the thickness of the bisphenol A epoxy resin above the first light emitting diode die 140 is relatively thin, even if due to individual differences, the part of the bisphenol A epoxy resin during the service life of the very individual light emitting diode packaging structure 10 Denaturation has occurred, but because of its thinner thickness, it has little effect on the overall light extraction performance. In addition, the stopper 116 can separate the first LED die 140 from the second LED die 142, so that the short-wavelength light from the first LED die 140 will not irradiate the second LED die 142 , preventing the second LED die 142 from absorbing the light from the first LED die 140 and reducing the light extraction efficiency.

Referring to FIG. 4 and FIG. 5 , the LED packaging structure 20 provided by the second embodiment of the present invention includes a substrate 11 , electrodes 12 , reflective cups 13 , LED die 24 and a packaging body 15 . The structural configuration of the substrate 11 , the electrodes 12 , the reflective cup 13 and the packaging body 15 is the same as that of the LED packaging structure 10 in the first embodiment.

The difference from the LED packaging structure 10 in the first embodiment is that the LED die 24 of the LED packaging structure 20 not only includes the first LED die 140 arranged in the first receiving portion 1340 and the second LED die 140 arranged in the second The second LED die 142 in the receiving portion 1342 , the LED die 24 further includes a third LED die 144 disposed in the first receiving portion 1340 .

The first LED die 140 and the third LED die 144 are disposed on the first electrode 121 and electrically connected to the first electrode 121 and the second electrode 122 respectively. The second LED die 142 is disposed on the third electrode 123 and electrically connected to the third electrode 123 and the fourth electrode 124 . In this embodiment, the first LED die 140 and the third LED die 144 are arranged in series. The light emitting wavelength of the first LED die 140 is smaller than the light emitting wavelength of the second LED die 142 , and the light emitting wavelength of the third LED die 144 is between the light emitting wavelength of the first LED die 140 and the second light emitting wavelength. Between the light emitting wavelengths of the diode die 142 . In this embodiment, the first LED die 140 is a blue LED die, the second LED die 142 is a red LED die, and the third LED die 144 is a green LED die. grain. Furthermore, the first LED grain 140 may be a blue LED grain with a light emitting wavelength of about 450 nanometers, and the second LED grain 142 may be a red light emitting diode grain with a light emitting wavelength of about 630 nanometers. , the third LED die 144 may be a green LED die with an emission wavelength of about 500 nanometers.

In addition to the above-mentioned advantages 1, 2, 3, 4, 5, and 6 of the LED packaging structure 10 in the first embodiment, this LED packaging structure 20 also has the ability to mix white light and is suitable for environmental lighting, backlight, etc. advantages in the device.

Of course, the first LED die 140 and the third LED die 144 are not limited to be disposed on the first electrode 121 , the first LED die 140 and the third LED die 144 can be respectively disposed on One of the first electrode 121 and the second electrode 122 can also be arranged on the second electrode 122, as long as the first LED crystal grain 140 and the third LED crystal grain 144 are connected in series and electrically connected to the first electrode 122. The electrode 121 and the second electrode 122 are sufficient.

In addition, it should be noted that, in order to clearly show the electrical connection of each LED grain in the LED packaging structure 10, 20, the cross-sectional views of the present invention shown in FIGS. 2 and 5 still retain the metal used to connect the LED grain line, but did not delete the corresponding part of the metal line that was cut out according to the actual dissection situation.

It can be understood that those skilled in the art can make other corresponding changes and deformations according to the technical concept of the present invention, and all these changes and deformations should belong to the protection scope of the claims of the present invention.

Claims (3)

1. a package structure for LED, including substrate, be arranged on the electrode of upper surface of base plate and anti- Penetrate cup, in being arranged in reflector and be electrically connected to the light-emitting component of electrode and being filled in reflector with Cover the packaging body of LED crystal particle, it is characterised in that: described upper surface of base plate is formed and is positioned at instead Penetrating the block bottom cup, the bottom space of reflector is separated into the first not connected resettlement section by this block With the second resettlement section, described light-emitting component includes that the first light emitting diode being arranged in the first resettlement section is brilliant Grain and the second LED crystal particle being arranged in the second resettlement section, this first LED crystal particle Wavelength less than the wavelength of the second LED crystal particle, be filled with the first packaging body in this first resettlement section, It is all filled with the second packaging body, this first packaging body in the headroom of this second resettlement section and reflector Material be cyclic aliphatic based epoxy resin, the material of this second packaging body is bisphenol A type epoxy resin.

2. package structure for LED as claimed in claim 1, it is characterised in that described block Size is gradually reduced to the direction away from substrate from upper surface of base plate.

3. package structure for LED as claimed in claim 1, it is characterised in that described first Optical diode grain is blue light-emitting diode crystal grain, and described second LED crystal particle is red light-emitting Diode crystal particle.