Summary of the invention
Technical problem to be solved by this invention is to provide a kind of large power white light LED part without the method for packing of the two-sided bright dipping of gold thread and encapsulating structure, they are in the both ends of the surface of LED chip P-N junction, two fluorescence excitation/conversion layers are set simultaneously, transparency electrode two end faces that are direct and LED chip P-N junction are adopted to carry out the electric connection mode of face contact type respectively, owing to no longer needing to manufacture gold electrode at chip surface.Simplify the package fabrication process of LED chip; The light extraction efficiency of LED chip can be significantly improved, efficiently solve the white light LED part encapsulation problem with spherical source feature, greatly expanded its application.
Technical scheme of the present invention is: provide a kind of large power white light LED part without the method for packing of the two-sided bright dipping of gold thread, comprise and obtain LED chip with LED blue light epitaxial wafer, at chip and draw outward and to arrange electrical connecting passage between stent electrode and arrange fluorescence excitation/conversion layer on chip, the packaging technology step described in it at least comprises the following steps:
A, employing single crystal fluorescent material, obtained first and second fluorescence excitations/conversion layer; The cross sectional dimensions of first, second fluorescence excitation/conversion layer described is more than or equal to the cross sectional dimensions of described LED blue light epitaxial wafer;
B, surface at LED blue light epitaxial wafer heavily doped P-type end, prepare one deck first transparent conductive film, and the LED blue light epitaxial wafer being loaded with the first transparent conductive film be divided into single LED chip;
C, surface at the first fluorescence excitation/conversion layer, prepare one deck second transparent conductive film equally;
D, the first and second described transparent conductive films, by implementing " eutectic " technique, by the surface of described LED chip P type end, be welded as a whole with the first fluorescence excitation/conversion layer, the cross-sectional area of LED chip P type end described in it, is less than the cross-sectional area of the first fluorescence excitation/conversion layer and the cross-sectional area of the second transparent conductive film;
E, employing " mask lithography " technique, not by the region that LED chip P type end surfaces hides on second transparent conductive film on the first fluorescence excitation/conversion layer surface, for the preparation of connecting the first conducting metal weld layer drawing stent electrode outside LED chip P end electrode and first;
F, employing " laser lift-off " technique, peel off the epitaxial substrate of LED chip, expose the surface of LED chip heavily doped N-type end;
G, employing " mask lithography " technique, on the surface of LED chip N-type end, prepare one deck the 3rd transparent conductive film;
F, surface at the second fluorescence excitation/conversion layer, prepare one deck the 4th transparent conductive film equally;
H, employing " mask lithography " technique, not by the region that LED chip N-type end surfaces hides on the 4th type transparent conductive film on the second fluorescence excitation/conversion layer surface, for the preparation of connecting the second conducting metal weld layer drawing stent electrode outside chip N end electrode and second;
I, the third and fourth described transparent conductive film, by implementing " eutectic " technique, by described LED chip N-type end surfaces, connect as one with the second fluorescence excitation/conversion layer, the cross-sectional area of LED chip N-type end described in it, is less than the cross-sectional area of the second fluorescence excitation/conversion layer and the cross-sectional area of the 4th transparent conductive film;
J, employing said method and step, at P type end side and the N-type end face of light emitting diode (LED) chip with vertical structure, corresponding formation first and the 3rd transparent conductive film respectively, on the surface of the first and second fluorescence excitations/conversion layer, respectively correspondingly form second and the 4th transparent conductive film, second and the 4th, transparent conductive film is loaded with first, second conducting metal weld layer respectively; The P type end side of described LED chip, through the first and second described transparent conductive films, affixed with the first fluorescence excitation/conversion layer; The N-type end face of described LED chip, through the third and fourth described transparent conductive film, corresponding with the second fluorescence excitation/conversion layer affixed; First, second described fluorescence excitation/conversion layer lays respectively at the both sides end face of LED chip P-N junction, forms the LED chip with double-side light-emitting structure;
K, by " Reflow Soldering " technique, by first, second conducting metal weld layer of described LED chip, respectively at P end face or the N end face of chip, and draw outside first outside stent electrode or second and draw between stent electrode, set up corresponding electrical connecting passage; Described transparency conducting layer and conducting metal weld layer, the form contacted by face, is respectively set up corresponding electrical connecting passage at the P end face of described LED chip and N end electrode with drawing between stent electrode outward, forms the LED component with double-side light-emitting structure.
Adopt the LED component with double-side light-emitting structure made of said method, at elimination gold electrode line to while going out light blocking, allow LED chip can two sides bright dipping, effectively increase the lighting area of LED chip, improve the light extraction efficiency of LED chip.
The LED component adopting said method to make, has the light extraction features of spherical source.
Further, between first, second described fluorescence excitation/conversion layer, multiple LED chip is provided with; When described LED chip quantity is n and n is greater than 2, by implementing " eutectic " technique, the P type end of all n LED chip and the first described fluorescence excitation/conversion layer are welded as a whole, the N-type end of all n LED chip and the second described fluorescence excitation/conversion layer are welded as a whole; Make between each LED chip, to form circuit structure in parallel.
Or, between first, second described fluorescence excitation/conversion layer, be provided with multiple LED chip; When described LED chip quantity is n and n is greater than 2, by implementing " eutectic " technique, the P type end of m LED chip and the N-type end of m+1 LED chip and the first described fluorescence excitation/conversion layer are welded as a whole, the N-type end of m LED chip and the P type end of m+1 LED chip and the second described fluorescence excitation/conversion layer are welded as a whole, make between each LED chip, to form the circuit structure of connecting successively; M is wherein odd number and m≤n-1.
Concrete, described first or the second fluorescence excitation/conversion layer, be Garnet fluorescent material monocrystal or the pottery containing Garnet fluorescent material or glass.
Described transparent conductive film comprises metal film series, transparent conductive oxide film is serial, composite membrane is serial and compound film series of conductor films.
Transparent conductive film described in it is indium tin oxide transparent conductive semiconductor film or Ni/Au conducting film.
Compound film series of conductor films described in it is polymeric membrane series of conductor films.
The preparation of described transparent conductive film and first, second conducting metal weld layer adopts photoetch method, mask means or silk screen print method.
Photoetch method described in it comprises laser dry etching method.
Described mask means comprises sprouts cover through sedimentation.
Present invention also offers a kind of large power white light LED part adopting said method obtained without the two-sided bright dipping encapsulating structure of gold thread, it is characterized in that:
At P type end side and the N-type end face of light emitting diode (LED) chip with vertical structure, correspondence arranges first and the 3rd transparent conductive film respectively;
On two end faces of LED chip P-N junction, correspondence arranges first, second fluorescence excitation/conversion layer respectively; First, second fluorescence excitation/conversion layer described lays respectively at the both sides end face of LED chip P-N junction;
On the opposite face of the first and second fluorescence excitations/conversion layer, second and the 4th transparent conductive film are set;
By first, second transparent conductive film, the P type end side of described LED chip and the first fluorescence excitation/conversion layer affixed;
By the 3rd, the 4th transparent conductive film, the N-type end face of described LED chip and the second fluorescence excitation/conversion layer affixed;
On the described second, the 4th transparent conductive film, be respectively arranged with the first and second conducting metal weld layers;
Described transparency conducting layer and conducting metal weld layer, the version contacted by face, LED chip P end face and N end electrode and draw outward between stent electrode, set up corresponding electrical connecting passage respectively, form the LED component with double-side light-emitting structure.
Further, between first, second described fluorescence excitation/conversion layer, multiple LED chip is provided with; P type end and the described first fluorescence excitation/conversion layer of all LED chips fix as one, and N-type end and the second described fluorescence excitation/conversion layer of all LED chips fix as one; Circuit structure in parallel is formed between each LED chip.
Further, between first, second described fluorescence excitation/conversion layer, multiple LED chip is provided with; Wherein, the P type end of odd number LED chip and the N-type end of even number LED chip, fix as one with described first fluorescence excitation/conversion layer, the N-type end of odd number LED chip and the P type end of even number LED chip, fix as one with described second fluorescence excitation/conversion layer; Make between each LED chip, to form the circuit structure of connecting successively.
Compared with the prior art, advantage of the present invention is:
1. adopt the technical program to carry out the encapsulation of White-light LED chip, no longer need to manufacture gold electrode at chip surface.Simplify chip making technology, eliminate gold electrode and the luminescence of LED chip is stopped, effectively can increase the lighting area of blue chip, improve LED light extraction efficiency;
2. they are in the both ends of the surface of LED chip P-N junction, arrange two fluorescence excitation/conversion layers simultaneously, adopt transparency electrode two end faces that are direct and LED chip P-N junction to carry out the electric connection mode of face contact type respectively, can significantly improve the light extraction efficiency of LED chip;
3. the LED component made by has the light extraction features of spherical source, has greatly expanded the application of LED.
Embodiment
Below in conjunction with drawings and Examples, the present invention will be further described.
In Fig. 1, the method for packing of the technical program comprises chip electrode processing procedure and at chip and draw outward and to arrange electrical connecting passage between stent electrode and arrange fluorescent material layer in the both sides of chip, the method for packing described in it at least comprises the following steps:
A, use single crystal fluorescent material, form the first and second fluorescence excitations/conversion layer;
B, at LED blue light epitaxial wafer heavily doped P-type end surfaces, prepare the first transparent conductive film;
C, the LED blue light epitaxial wafer being loaded with the first transparent conductive film is divided into LED chip;
D, surface at the first fluorescence excitation/conversion layer, prepare the second transparent conductive film;
E, by " eutectic " technique, by LED chip P type end side, to fix as one with the first fluorescence excitation/conversion layer;
F, use " laser lift-off " technique, peel off the epitaxial substrate of LED chip, exposes LED chip heavily doped N-type end face;
G, on the second transparent conductive film, by " mask lithography " technique, for the preparation of connecting the first conducting metal weld layer drawing stent electrode outside LED chip P end electrode and first;
H, use " mask lithography " technique, on the surface of LED chip N-type end, preparation the 3rd transparent conductive film;
I, use " mask lithography " technique, for the preparation of connecting the second conducting metal weld layer drawing stent electrode outside LED chip N end electrode and second on the 4th type transparent conductive film;
J, by " eutectic " technique, by LED chip N-type end face, to fix as one with the second fluorescence excitation/conversion layer;
K, employing said method and step, by the P type end side of the LED chip of vertical stratification, through the first and second transparent conductive films, affixed with the first fluorescence excitation/conversion layer; By the N-type end face of LED chip, through the third and fourth transparent conductive film, corresponding with the second fluorescence excitation/conversion layer affixed; Second and the 4th, transparent conductive film is loaded with first, second conducting metal weld layer respectively; Form the LED chip with double-side light-emitting structure;
L, use " Reflow Soldering " technique, by first, second conducting metal weld layer of LED chip, and draw outside first outside stent electrode or second and draw between stent electrode, sets up corresponding electrical connecting passage;
M, first to fourth transparency conducting layer described in it and first, second conducting metal weld layer, by the form that face contacts, respectively set up corresponding electrical connecting passage at the P end face of chip and N end electrode with drawing between stent electrode outward, form the LED component with double-side light-emitting structure and spherical source light extraction features.
Adopt the LED component with double-side light-emitting structure made of said method, at elimination gold electrode line to while going out light blocking, allow LED chip can two sides bright dipping, effectively can increase the lighting area of LED chip, improve the light extraction efficiency of LED chip/device.
The LED component adopting said method to make, has the light extraction features of spherical source.
Concrete, described first or the second fluorescence excitation/conversion layer, be Garnet fluorescent material monocrystal or the pottery containing Garnet fluorescent material or glass.
Described transparent conductive film comprises metal film series, transparent conductive oxide film is serial, composite membrane is serial and compound film series of conductor films.
Transparent conductive film described in it is indium tin oxide transparent conductive semiconductor film or Ni/Au conducting film.
Compound film series of conductor films described in it is polymeric membrane series of conductor films.
The preparation of described transparent conductive film and first, second conducting metal weld layer adopts photoetch method, mask means or silk screen print method.
Photoetch method described in it comprises laser dry etching method.
Described mask means comprises sprouts cover through sedimentation.
In actual production process, existing employing fly line method/routing method produces the line capacity of LED chip close to saturated, but also can not meet actual market demand far away; Contrary, the IC chip packing producing line that Ge great integrated circuit production firm has is faced with serious excess production capacity, is faced with the situation of under-capacity operation.
Due to the difference of production process for encapsulating, the production efficiency/production capacity of IC chip packing producing line, far away higher than existing LED chip packing producing line.
If existing IC chip packing producing line can be utilized to encapsulate LED chip, then can improve the production capacity of LED significantly and reduce production cost, to the production/supplier of integrated circuit production firm and LED, are all things of a doulbe-sides' victory.
One of starting point of the technical program, be solve LED chip two-sided go out optical issue, its another main starting point is exactly, utilize IC chip packing producing line and the production technology thereof with ripe production capacity, LED chip is encapsulated, improves the production capacity of LED significantly and reduce production cost.
Therefore in the technical program, have employed the production technology of existing IC chip packing producing line in large quantities, such as, epitaxial substrate involved in foregoing description is peeled off, transparent conductive film and conductive metal electrode and preparation method thereof, comprise " eutectic " technique, " laser lift-off " technique, " mask lithography " technique or " Reflow Soldering " technique, be the prior art of technical maturity in IC chip packing producing line, therefore its concrete methods of realizing and implementation process no longer describe at this.
In Fig. 2, the technical program provides a kind of large power white light LED part adopting above-mentioned method for packing obtained without the two-sided bright dipping encapsulating structure of gold thread, and its design feature is:
At P type end side 4 and the N-type end face 9 of light emitting diode (LED) chip with vertical structure, correspondence arranges first and the 3rd transparent conductive film 3 and 8 respectively;
On two end faces of LED chip P-N junction, correspondence arranges first, second fluorescence excitation/conversion layer 1 and 6 respectively; First, second fluorescence excitation/conversion layer described lays respectively at the both sides end face of LED chip P-N junction;
On the opposite face of the first and second fluorescence excitations/conversion layer, correspondence arranges the second transparent conductive film 2 and the 4th transparent conductive film 7 respectively;
By first, second transparent conductive film 2 and 3, the P type end side 4 of described LED chip and the first fluorescence excitation/conversion layer 1 affixed;
By the 3rd, the 4th transparent conductive film 7 and 8, the N-type end face of described LED chip and the second fluorescence excitation/conversion layer 6 affixed;
On the second described transparent conductive film 3 and the 4th transparent conductive film 7, be respectively arranged with the first conducting metal weld layer 5 and the second conducting metal weld layer 10;
Described transparency conducting layer and conducting metal weld layer, by the version that face contacts, LED chip P end face and N end electrode and draw between stent electrode (not shown) outward, set up corresponding electrical connecting passage respectively, form the LED component with double-side light-emitting structure.
As seen from the figure, the space that conducting metal weld layer 5 and 10 top is reserved allows the outer stent electrode that draws to be attached thereto and to connect.
Its LED chip adopted is vertical stratification.
Above-mentioned fluorescent material comprises Garnet fluorescent material monocrystal or contains pottery or the glass of Garnet fluorescent material.
Above-mentioned transparent conductive film comprises metal film series, transparent conductive oxide film series, polymeric membrane is serial, composite membrane is serial and compound film series of conductor films.
Preferably, described transparent conductive film is indium tin oxide transparent conductive semiconductor film or Ni-Au conducting film.
The preparation of above-mentioned transparent conductive film and conductive metal electrode adopts photoetch method, mask means, laser dry etching method, silk screen print method or sprouts cover through sedimentation.
In Fig. 3, as seen from the figure, LED chip B through the conducting metal weld layer that is arranged on fluorescence excitation/conversion layer A, respectively with draw support positive and negative electrode 13,15 outward and correspondingly to connect.
Drawing support outward by drawing stent electrode pin fixed block 14 outward, drawing support positive electrode 13 outward, draw support electricity negative pole 15 outward and jointly form.
Conducting metal weld layer 5 and 10 is corresponding connects with first, second respectively to draw support positive electrode and negative electrode outward.
Draw stent electrode pin fixed block 13 outward and draw stent electrode outside supporting.
It is outer, and to draw stent electrode can be long pin for patching welding, also can be the pad for paster welding.
In Fig. 4, give the embodiment schematic diagram that plurality of LEDs chip adopts parallel-connection structure, it is particularly suitable for producing high-power LED luminescent device.
Its LED chip is vertical stratification, between the first fluorescence excitation/conversion layer 1 and the second fluorescence excitation/conversion layer 6, is provided with multiple LED chip.
The P type end 4 of all LED chips, fixes as one with the first fluorescence excitation/conversion layer 1, and the N-type end 9 of all LED chips, fixes as one with the second described fluorescence excitation/conversion layer 6; Formation like this electrically connect as parallel-connection structure.
In other words, in the present embodiment, when described LED chip quantity is n and n is greater than 2, by implementing " eutectic " technique, the P type end of all n LED chip and the first described fluorescence excitation/conversion layer are welded as a whole, the N-type end of all n LED chip and the second described fluorescence excitation/conversion layer are welded as a whole; Make between each LED chip, to form circuit structure in parallel.
In Figure 5, give the embodiment schematic diagram that plurality of LEDs chip adopts cascaded structure, similarly, it is also particularly suitable for producing high-power LED luminescent device.
Its LED chip is vertical stratification, between the first fluorescence excitation/conversion layer 1 and the second fluorescence excitation/conversion layer 6, is provided with multiple LED chip.
As seen from the figure, the p side electrode 4-1 of first LED chip is connected with the first fluorescence excitation/conversion layer 1; First fluorescence excitation/conversion layer 1 is also connected with the N face electrode 9-2 of second LED chip simultaneously, and the p side electrode 4-2 of second LED chip is then connected with the second fluorescence excitation/conversion layer 6, and what so formed electrically connects as cascaded structure.
In other words, when described LED chip quantity is n and n is greater than 2, by implementing " eutectic " technique, the P type end of m LED chip and the N-type end of m+1 LED chip and the first described fluorescence excitation/conversion layer are welded as a whole, the N-type end of m LED chip and the P type end of m+1 LED chip and the second described fluorescence excitation/conversion layer are welded as a whole, m is wherein odd number and m≤n-1; Make between each LED chip, to form the circuit structure of connecting successively.
In other words, the present embodiment, between first, second described fluorescence excitation/conversion layer, is provided with multiple LED chip; Wherein, the P type end of odd number LED chip and the N-type end of even number LED chip, fix as one with described first fluorescence excitation/conversion layer, the N-type end of odd number LED chip and the P type end of even number LED chip, fix as one with described second fluorescence excitation/conversion layer; Make between each LED chip, to form the circuit structure of connecting successively.
In the present embodiment, the coating of transparent conductive film 21 and 3 and transparent conductive film 7 and 8 will have complicated graphic designs.
Adopt technical solution of the present invention to encapsulate White-light LED chip, no longer need to manufacture gold electrode at chip surface, which simplify chip and make technique; It adopts transparency electrode P-N junction that is direct and LED chip to carry out the electrical connection of face contact type, and two fluorescence excitation/conversion layers of setting, can significantly improve the light extraction efficiency of LED, efficiently solves the white light LED part encapsulation problem with spherical source feature.
The enforcement of the technical program, while elimination gold electrode stops luminescence, allows LED chip can two sides bright dipping, effectively can increase the lighting area of blue-light LED chip, improve the light extraction efficiency of LED; Made LED component has spherical source feature, has greatly expanded LED component application.
The present invention can be widely used in the manufacturing field of white light LED luminescent device.