The electrode structure of light-emitting component
Technical field
The present invention relates to a kind of electrode structure of light-emitting component, particularly relevant for a kind of be the electrode structure of light-emitting component that framework forms with the hexagon.
Background technology
Because gallium nitride (GaN) has wide band gap (Eg=3.4eV at room temperature) and its light emitting region near blue light wavelength, therefore gallium nitride is suitable as the material of short-wave long light-emitting element very much, also so also becomes and develops one of material the most popular in the photoelectric cell in recent years.Through constantly research and development, if the growth that present technology can be stable with gallium nitride and again via the suitable crystalline substance of heap of stone and the arrangement of electrode, can produce short wavelength's light-emitting component on sapphire (sapphire) substrate.
As shown in Figure 1, be the schematic configuration vertical view of a prior art light-emitting element electrode.First electrode 110 is when applied voltage, electric current can flow in this light-emitting component via coupled contact mat, and when forward passing through its inner P/N and connect face cause reconfiguring of minority carrier and produce power is luminous, electric current can be via different paths (for example: current path 112,114 and 116 etc.) conflux to second electrode 120, and flow out this light-emitting component by the contact mat that is connected with second electrode 120 afterwards.Yet it is not all to be equidistant current path to the path of second electrode 120 that electric current confluxes from first electrode 110, therefore causes the phenomenon of non-homogeneous CURRENT DISTRIBUTION yet, and causes the uneven situation of this light-emitting component luminosity to produce.For example: edge current path 112 and 116 current density be because of the long relation of path distance, thus can be lower than the current density of center current path 114, so light-emitting component at the luminosity of its marginal portion just not as good as the luminosity of heart part therein.In addition, the electric current distribution inequality also is the one of the main reasons that causes the light-emitting component reliability not good.
In order to promote the luminosity of light-emitting component, gallium nitride (GaN) light-emitting component turns to high power and the development of large tracts of land element gradually, as shown in Figure 2, inserts the schematic configuration vertical view of shape electrode at the common finger of high power semiconductor element for another kind.First electrode, the 150 vertical extension electrode 150-1 and the 150-2 that are parallel to each other of connecting form a so-called finger electrode structure.And extension electrode 160-1,160-2 and 160-3 that the also vertical connection of second electrode 160 is parallel to each other form another finger electrode structure.Because two finger electrode structure form mutual interting and parallel electrode structure, its each extension electrode is with spacing between adjacent extension electrode and equates, therefore, electric current is equidistant current path from the distance that extension electrode flows to adjacent extension electrode, by this current density and the luminous intensity of each several part in the average luminescence element.Increase along with the distance with electrode and become big yet above-mentioned finger is inserted the impedance meeting of shape structure on extension electrode, for example: the impedance to first electrode 150 was greater than the impedance to first electrode 150 in A o'clock in B o'clock.This means flow to current strength that B orders can be littler than flowing to the current strength that A orders, therefore also can be lower near the current density the extension electrode B point than near the current density the A point, thereby cause near the luminous intensity of B point also with regard to a little less than near the luminous intensity the relative ratio A point.
The shortcoming of light-emitting element electrode structure and the restriction when actual production in view of the above, having in fact needs the new improvement structure of sustainable development to overcome the every defective in the Prior Art.So, how equidistant two interelectrode current paths, how could use the standard processing procedure to satisfy the different demands of high power luminous element apart from impedance and layout how between average electrode and extension electrode, being the problem that this technical field will inevitably meet with, also is problem to be solved by this invention.
Summary of the invention
In the foregoing invention background, it is uneven and apart from the equal problem of impedance that the electrode structure of light-emitting component has CURRENT DISTRIBUTION in the prior art.The present invention utilizes hexagon can be covered with whole plane geometry characteristic, and providing a kind of is the electrode structure of light-emitting component that framework forms with the hexagon, improves all shortcoming of the prior art with this.
One of purpose of the present invention is, by a kind of be the formed electrode structure of framework with the hexagon so that the interelectrode current path of first electrode to the second is equidistant.
Another object of the present invention is, by a kind of be the formed electrode structure of framework with the hexagon, between its each adjacent vertex apart from same concept, between average electrode and extension electrode apart from impedance.
According to the above purpose, the invention provides a kind of electrode structure of light-emitting component, comprise: one first electrode, this first electrode comprises a plurality of first finger portion parallel to each other, a first pontes and at least one first contact portion, each first finger portion has one first end and one second end, wherein these first ends are connected to the first pontes, and first contact portion is inserted (interpose) between arbitrary first end and the first pontes; And one second electrode, this second electrode comprises a plurality of second finger portion parallel to each other, one second coupling part and at least one second contact portion, each second finger portion has one the 3rd end and one the 4th end, wherein arbitrary second finger portion is between adjacent wantonly two first finger portion, and these grade in an imperial examination three ends are connected to second coupling part, and second contact portion is inserted between arbitrary the 3rd end and second coupling part.The a plurality of hexagonal cells of wherein above-mentioned second electrode definition are between above-mentioned a plurality of second ends, each hexagonal cells is total to limit and other hexagonal cells next-door neighbour with four, per two second finger portion and second coupling part are formed four of each hexagonal cells and are total to the limit, and each second end extends to each hexagonal cells geometric center by other two limits of each hexagonal cells.
Description of drawings
Fig. 1 is the schematic configuration vertical view of a prior art light-emitting element electrode;
Fig. 2 refers to insert the schematic configuration vertical view of shape electrode for another prior art light-emitting component;
Fig. 3 A is the electrode structure vertical view of a preferable light-emitting component of the present invention; And
Fig. 3 B adds the hexagonal vertical view of hypothesis for Fig. 3 A.
Symbol description among the figure:
110,150 first electrodes
112,114,116 current paths
120,160 second electrodes
150-1, the 150-2 first electrode extension electrode
160-1,160-2, the 160-3 second electrode extension electrode
310 first finger portion
320 the first pontes
330 first contact portions
340 second finger portion
350 second coupling parts
360 second contact portions
370,380 hexagonal cells
A, B A point, B point
Embodiment
Some embodiments of the present invention can be described in detail as follows.Yet except describing in detail, the present invention can also be widely implements at other embodiment, and scope of the present invention do not limited, its with after claim be as the criterion.
And for clearer description being provided and being more readily understood the present invention, each several part is not drawn according to its relative size in the accompanying drawing, and some size and other scale dependent ratio are exaggerated; Uncorrelated detail section is not drawn fully yet, succinct in the hope of accompanying drawing.
The invention provides a kind of electrode structure of light-emitting component, comprise: one first electrode, this first electrode comprises a plurality of first finger portion parallel to each other, a first pontes and at least one first contact portion, each first finger portion has one first end and one second end, wherein these first ends are connected to the first pontes, and first contact portion is inserted (interpose) between arbitrary first end and the first pontes; And one second electrode, this second electrode comprises a plurality of second finger portion parallel to each other, one second coupling part and at least one second contact portion, each second finger portion has one the 3rd end and one the 4th end, wherein arbitrary second finger portion is between adjacent wantonly two first finger portion, and these grade in an imperial examination three ends are connected to second coupling part, and second contact portion is inserted between arbitrary the 3rd end and second coupling part.The a plurality of hexagonal cells of wherein above-mentioned second electrode definition are between above-mentioned a plurality of second ends, each hexagonal cells is total to limit and other hexagonal cells next-door neighbour with four, per two second finger portion and second coupling part are formed four of each hexagonal cells and are total to the limit, and each second end extends to each hexagonal cells geometric center by other two limits of each hexagonal cells.
As shown in Figure 3A, be the electrode structure schematic diagram of a preferred embodiment of the present invention.First electrode comprises a plurality of first finger portion 310 parallel to each other, the first pontes 320 and at least one first contact portion 330 that connects these first finger portion, 310 bottoms.Wherein, first contact portion 330 can be inserted between arbitrary first finger portion, 3 10 bottoms and the first pontes 320.In the present embodiment, first contact portion 330 of two rectangles compartment of terrain is respectively inserted first finger portion, 3 10 bottoms, and the part of formation metal contact pad (contactpad), what this must emphasize be, first contact portion in the present embodiment is not only to be confined to rectangular geometry, and it can also other geometry replace.
Second electrode comprises a plurality of second finger portion 340 parallel to each other, second coupling part 350 and at least one second contact portion 360 that connects these second finger portion, 340 bottoms.Wherein, the top of these second finger portion 340 is parallel to be interspersed between adjacent any two first finger portion 310, and second contact portion 360 can be inserted between arbitrary second finger portion, 340 bottoms and second coupling part 350.In the present embodiment, second contact portion 360 of two circles lays respectively at the bottom of both sides second finger portion 340 and is connected with second coupling part 350, to form the part of metal contact pad, in like manner, second contact portion is not only to be confined to circular geometry, and it can also other geometry replace.
And a plurality of hexagonal cells 370,380 of above-mentioned second electrode definition are between these first finger portion, 310 tops, shown in Fig. 3 B.Each hexagonal cells 370,380 is with four altogether limit (for example: two adjacent and equidirectional second finger portion 340 and second coupling part 350 that connects this two second finger portion 340) and other hexagonal cells 370,380 next-door neighbours, and per two adjacent equidirectional second finger portion 340 also can be formed four of each hexagonal cells 370,380 limits altogether with second contact portion 360.In the present embodiment, four of each hexagonal cells 370 common limits comprise 0~1 second contact portion 360; And four common limits of each hexagonal cells 380 comprise 1 second contact portion 360.In addition, the top of each first finger portion 310 extends to each corresponding hexagonal cells 370,380 geometric center by each corresponding hexagonal cells 370,380 other two limit.
In other words, above-mentioned each finger portion, coupling part and contact portion are described, and all are to be that framework is arranged with continuous hexagon.Please refer again to Fig. 3 B, the a plurality of summits that link to each other with 380 with a plurality of hexagonal cells 370 are respectively as the bottom of a plurality of second finger portion 340, and according to wantonly two adjacent hexagonal cells 370 limits and wantonly two adjacent hexagonal cells 380 common limits form a plurality of second finger portion 340 altogether, only be formed at second finger portion 340 on hexagonal cells 370 common limits, its direction is opposite with second finger portion 340 that is formed at hexagonal cells 380 common limits.The hexagonal cells 370 and 380 that is connected by second finger portion, 340 bottoms therewith forms second coupling part 350 in limits altogether then.310 of first finger portion are positioned at the place, relative summit of place, second finger portion, 340 bottom hexagonal cells 370.First contact portion 330 and second contact portion 360 then can be selected to form in the place, summit of hexagonal cells 370.In addition, first finger portion 310 more can form 380 pairs of angular vertex places of the identical hexagonal cells of size and form between adjacent hexagons unit 370, and only its direction is opposite with first finger portion 310 on the hexagonal cells 370.
At last on a plurality of hexagonal cells 370 and 380 formed complete planes, between per two adjacent and equidirectional second finger portion 340 first finger portion 310 in parallel is arranged all; In other words, also relative second finger portion 340 in parallel that has between per two adjacent first finger portion 310.Because the length of side on hexagonal cells 370,380 each limit equates and 340 of first finger portion 310 and second finger portion apart from approximately equal, therefore by suitable layout (layout) first contact portion 330 and second contact portion 360 are assigned in the summit of hexagonal cells 370,380, can make two interelectrode current paths approximate equidistant, more on average between electrode and extension electrode apart from impedance.And suitable layout system the considering according to factors such as electric current dispersion and light transmissions of above-mentioned what is called, for example: the wire rod of general routing (bonding) less than the electric current of high power luminous element institute practical application, therefore disperses electric current to avoid wire rod to blow because of electric current is excessive by the mode that increases contact portion and wire rod on the specification of current limliting; Yet the light that too much contact portion can make light-emitting component launch is blocked and causes the reduction of light-emitting component luminous efficiency.Therefore based on above two considering of factor and the suitable number that depends on contact portion, and wherein the number of contact portion does not limit palpus symmetrically, that is to say that the number of first contact portion can also can be less than the number of second contact portion more than the number of second contact portion.
Comprehensive above-mentioned preferred embodiment, the present invention emphasized be light-emitting component (for example: light-emitting diode (Light Emitting Diode; LED)) hexagonal geometric layout and structure between two electrodes utilize the distance between the arbitrary adjacent vertex of hexagon to equate notion, improve between electrode and extension electrode and produce the different problem of impedance because of distance; Utilize hexagonal centre point to the distance between each summit to equate notion, equidistant two interelectrode current paths.In addition, utilize the symmetrical geometrical pattern of hexagon, make the entire chip plane do the most effective area utilization, use the improvement light-emitting component and utilize problem because of the area that the asymmetry electrode structure is caused.In other words, average current density and luminous intensity and under the considering of large size chip area utilization in the light-emitting component subsection, hexagonal electrode structure all can meet above-mentioned conditional request and also be spiritual place of the present invention.
The above only is preferred embodiment of the present invention, is not in order to limit claim of the present invention; All other finished equivalence and changed or modify by the disclosed spirit of disengaging is following, all should be included in the described claim.