CN111900152B - Integrated unit diode chip - Google Patents

Abstract

The present invention provides an integrated unit light-emitting diode, comprising: electrodes of a first conductivity type, electrodes of a second conductivity type, pads of a second conductivity type and n diode units, the length of the n diode units along the Y axis direction being less than the current diffusion length, wherein, n≥2; the n diode units shown include a hole structure. The invention solves the technical problem that the diode structure in the prior art has great limitations on the three important parameters of lumen efficiency, lumen density output and lumen cost, improves the lumen output of the chip per unit area, and reduces the lumen cost.

Description

An integrated unit diode chip

technical field

The invention relates to the field of semiconductor materials and device technology, in particular to semiconductor optoelectronic devices.

Background technique

In conventional vertical structure LED chips, the current diffusion mainly depends on the n-electrode side, and there are electrode lead-type leads or drill-type leads, but the overall current diffusion is still uneven, resulting in loss of luminous efficiency and uneven heat dissipation, thus affecting the unit. Efficiency and stability of diode chips. This restricts vertical high-power LED chips from providing products with higher lumen output per unit area. Uneven current diffusion, uneven thermal diffusion, and uneven light extraction lead to great limitations in the three important parameters of lumen efficiency, lumen density output, and lumen cost. The vertical LED chip technology currently on the market An effective solution cannot be provided.

Existing technology one is Proc.of SPIE Vol.10021 100210X-1 2016 conference paper, as shown in Figure 1-3, wherein Figure 1 is a structural diagram of a vertical LED chip, in which the p-type electrode is connected to the electrode on the back (back metal Au), the box on the edge of the black part and the three finger-shaped leads in the middle represent the n-type electrodes, which are drawn out through the two large N-pads below. Therefore, the current diffusion of the entire chip is mainly limited by the n-type metal wires.

FIG. 2 shows the near-field analysis diagram and the normalized current distribution diagram on the center line of the vertical chip in the prior art 1, and the size of the chip is 1.2mm×1.2mm. It can be seen from the near-field diagram that the current distribution of the chip is still very uneven. The area close to the n-electrode line has a large light intensity and a high current density, while the area far away from the n-electrode line has a small light intensity and a low current density. The normalized profile shows that the area with less current density is less than 70% of the larger area. Therefore, LED light efficiency, heat dissipation and stability under high current will be severely limited.

Contents of the invention

In order to solve the technical problems of the prior art that have great limitations on the three important parameters of diode structure lumen efficiency, lumen density output and lumen cost, the invention proposes an integrated unit diode with high lumen efficiency and large lumen density output .

To achieve the above object, the present invention provides an integrated unit diode chip, comprising: electrodes of the first conductivity type, electrodes of the second conductivity type, pads of the second conductivity type and n diode units, the n diode units along the Y axis The direction length is smaller than the current diffusion length, wherein, n≥2; the n diode units shown include hole structures.

Preferably, the electrodes of the second conductivity type are composed of strip-shaped electrode lines.

Preferably, the linear electrode wires adopt a linear layout, and some or all of them adopt a non-linear layout.

Preferably, the non-linear layout includes broken line layout and curved layout.

Preferably, the pore structure includes 1 to 1,000,000 pore units, and the diameter of the pore units is 0.001 micron to 20 microns.

Preferably, there is a mirror between the diode unit and the substrate.

Preferably, the reflector material is silver, aluminum or distributed Bragg reflector.

Preferably, the pore units are arranged symmetrically, asymmetrically, periodically, non-periodically or randomly.

Preferably, each diode unit contains 1 to 1,000,000 hole units, and the shapes of the hole units are triangles, squares, rectangles, pentagons, hexagons, circles, and other arbitrary defined shapes.

Preferably, the connection mode of the diode units is parallel connection, series connection or a series-parallel combination with a set ratio.

Preferably, the shape of the diode unit is: triangle, square, rectangle, pentagon, hexagon, circle, any custom shape.

Preferably, the number of the diode units is 2 to 100 billion.

Preferably, the length of the diode unit along the Y-axis is 0.001 micron to 200 micron.

Preferably, the diode units are distributed in a uniform and symmetrical arrangement.

Preferably, the diode units are arranged in different sizes and distributed unevenly.

Preferably, the line-shaped electrode line is made of line-shaped metal and/or indium tin oxide material; the line-shaped metal material is aluminum, silver, titanium, nickel, gold, platinum, chromium, or any two of the above and Alloys of the above metals.

Preferably, the integrated unit diode chip includes: a back electrode, a substrate, a protective metal layer, a mirror, a first conductivity type layer, a quantum well active region, and a second conductivity type layer.

Preferably, the back electrode material is aluminum, silver, titanium, nickel, gold, platinum, chromium, tin, or an alloy of any two or more of the above metals.

Preferably, the material of the protective metal layer is aluminum, silver, titanium, nickel, gold, platinum, chromium, tin, tungsten, or an alloy of any two or more of the above metals.

Preferably, the reflector material is silver, aluminum, distributed Bragg reflector.

Preferably, the light emitted by the integrated unit diode chip is UVC, UVB, UVA, violet, blue, green, yellow, red or infrared.

Preferably, when the light emitted by the integrated unit diode chip is UVC, UVB, UVA, violet, blue, green, yellow or red, the luminescent material is Al _x1 In _y1 Ga _z1 N, 1≥x1, y1, z1≥ 0; the substrate is a planar substrate or a patterned substrate; the substrate material is sapphire, silicon carbide, gallium nitride, aluminum nitride, gallium oxide or silicon.

Preferably, when the unit diode chip emits light waves of yellow light, red light, and infrared light, the luminescent material is Al _x2 In _y2 Ga _z2 P, 1≥x2, y2, z2≥0, Al _x3 In _y3 Ga _z3 As, 1 ≥x3,y3,z3≥0,Al _x4 In _y4 Ga _z4 As _u P _v ,1≥x4,y4,z4,u,v≥0; the substrate is a planar substrate, or a patterned substrate, a substrate The bottom material is indium phosphide, gallium arsenide, sapphire or silicon.

Preferably, the size of the integrated unit diode chip is 0.1 micron×0.1 micron to 100000 micron×100000 micron.

Preferably, the power of the integrated unit diode chip is 0.0001W-1000W.

The integrated unit diode chip used in the present invention breaks through the limitations of the existing vertical LED technology in three levels of light, electricity and heat through the nano-micron size structure effect. The size design of the unit diode chip is controlled within the current diffusion length, and its high-degree-of-freedom geometric optimization design method can simultaneously solve the problem of uneven current diffusion of the n-electrode and p-electrode that plagues the design of the LED unit diode chip, thus obtaining Higher photoelectric conversion efficiency/lumen efficiency; the nano-microstructure of each diode unit, and the hole structure inside the mesa can increase the effective light output area, thereby improving the light extraction efficiency; the size reduction of the integrated unit diode chip and the hole structure inside the mesa , bring a larger heat dissipation area, have better heat dissipation performance, allow the injection of ultra-high current density without affecting its stability, thereby greatly improving the lumen output per unit area of the integrated unit diode chip and reducing the lumen cost.

Description of drawings

FIG. 1 is a structural diagram of a diode unit in the prior art.

Fig. 2 is a structural diagram of a diode unit in the prior art.

FIG. 3 is a top view of the integrated unit diode chip provided by Embodiment 1 of the present invention.

Fig. 4 is a top view of the integrated unit diode chip provided by Embodiment 2 of the present invention.

FIG. 5 is a schematic diagram of an integrated unit diode chip provided by Embodiment 1-2 of the present invention.

Second conductivity type electrode 1, second conductivity type layer 2, quantum well active region 3, first conductivity type layer 4, mirror 5, protective metal layer 6, substrate 7, back electrode 8, second conductivity type solder Disc 9 , diode unit 10 , hole structure 11 .

Detailed ways

The technical solutions in the embodiments of the present invention are clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In view of the great limitations of the three important parameters of the existing diode structure, lumen efficiency, lumen density output, and lumen cost, the embodiment of the present invention provides an integrated unit diode with high lumen efficiency and large lumen density output. The figures illustrate the invention in detail.

The invention provides an integrated unit diode chip, comprising:

Electrodes of the first conductivity type, electrodes of the second conductivity type, pads of the second conductivity type and n diode units, the length of the n diode units along the Y-axis direction is less than the current diffusion length, wherein n≥2; n shown The diode unit includes a hole structure.

Preferably, the electrodes of the second conductivity type are composed of strip-shaped electrode lines.

Preferably, the line-shaped electrode line adopts a linear layout, and part or all of the design adopts a non-linear layout, wherein the non-linear layout includes a broken line layout and a curved line layout. 10 microns, using linear metal and/or indium tin oxide material, wherein the linear metal material is aluminum, silver, titanium, nickel, gold, platinum, chromium, or an alloy of any two or more of the above metals.

The n diode unit structures include a hole structure, and the hole structure includes 1 to 1,000,000 hole units, and the diameter of the hole units is 0.001 micron to 20 microns, and the hole units are arranged symmetrically, asymmetrically, periodically, non-periodically, or Arranged randomly, each diode unit contains 1 to 1,000,000 hole units, and the shape of the hole units is triangle, square, rectangle, pentagon, hexagon, circle, and other arbitrary defined shapes.

A reflection mirror is provided between the diode unit and the substrate, and the material of the reflection mirror is silver, aluminum or a distributed Bragg reflection mirror. The connection mode of the diode unit is parallel connection, and the shape of the diode unit is: triangle, square, rectangle, pentagon, hexagon, circle, any custom shape. The number of diode cells is 2 to 100 billion. The length of the diode unit along the Y-axis direction is 0.001 micron to 200 micron. The diode units are arranged in a uniform and symmetrical arrangement. Diode units are set in different sizes and unevenly distributed.

The integrated unit diode chip also includes: a back electrode, a substrate, a protective metal layer, a mirror, a first conductivity type layer, a quantum well active region, and a second conductivity type layer. The back electrode material is aluminum, silver, titanium, nickel, gold, platinum, chromium, tin, or an alloy of any two or more of the above metals. The material of the protective metal layer is aluminum, silver, titanium, nickel, gold, platinum, chromium, tin, tungsten, or an alloy of any two or more of the above metals. Mirror material is silver, aluminum, distributed Bragg reflector.

The integrated unit diode chip emits light waves of UVC, UVB, UVA, purple, blue, green, yellow, red or infrared. When the light wave is UVC, UVB, UVA, purple, blue, green, yellow or red The light-emitting material is Al _x1 In _y1 Ga _z1 N, 1≥x1, y1, z1≥0; the substrate is a planar substrate, or a patterned substrate; the substrate material is sapphire, silicon carbide, gallium nitride, nitrogen aluminum oxide, gallium oxide, or silicon. When the light wave of the sheet is yellow light, red light and infrared light, the luminescent material is Al _x2 In _y2 Ga _z2 P, 1≥x2, y2, z2≥0, Al _x3 In _y3 Ga _z3 As, 1≥x3, y3, z3 ≥0,Al _x4 In _y4 Ga _z4 As _u P _v ,1≥x4,y4,z4,u,v≥0; the substrate is a planar substrate, or a patterned substrate, and the substrate material is indium phosphide, arsenic gallium chloride, sapphire or silicon.

The size of the integrated unit diode chip is 0.1 micron×0.1 micron to 100000 micron×100000 micron. The power of the integrated unit diode chip is 0.0001W-1000W.

Example 1

This embodiment provides an integrated unit diode chip, as shown in FIG. 3 , including: a second conductivity type electrode 1 , a second conductivity type pad 9 and a diode unit 10 . Wherein, the second conductivity type electrode 1 is an n-type electrode, and the second conductivity type pad 9 is an n-type pad.

The diode unit is a rectangle with the same size and part, and the length of the evenly distributed diode unit along the Y-axis longitudinal direction is 80 microns, which is smaller than the current diffusion length. Diode units are connected in parallel. A hole structure 11 is added to each diode unit, and there are 81 circular hole units in total. The 4 diode units near the long side each have 12 hole units, and the 3 diode units in the middle each have 11 hole units with a diameter of 1 nm to 20 microns. The pore units are arranged symmetrically. The arrangement of hole units can also be asymmetric arrangement, periodic arrangement, non-periodic arrangement or random arrangement, and the shape of hole units can also be triangular, square, rectangular, pentagonal, hexagonal, circular, and other arbitrary definitions The shape is not limited to the arrangement and shape shown in FIG. 3 . The n-type electrode is a line-shaped electrode line, which adopts a straight line layout. The width of the electrode line is 0.001-10 microns, and the thickness is 0.001-20 microns. The material of the electrode line is aluminum or silver or an alloy of the above two metals.

In some preferred embodiments, the length of the diode unit along the Y-axis longitudinal direction is 100 microns; in other preferred embodiments, the length of the diode unit along the Y-axis longitudinal direction is 10 microns; in other preferred embodiments, The length of the diode unit along the Y-axis longitudinal direction is 1 μm.

As shown in Figure 5, an integrated unit diode chip also includes a second conductivity type layer 2, a quantum well active region 3, a first conductivity type layer 4, a mirror 5, a protective metal layer 6, a substrate 7, and a back electrode 8. Wherein the second conductivity type layer 2 is an n-GaN layer, and the first conductivity type layer 4 is a -GaN layer. The back electrode material is aluminum, silver, titanium, nickel, gold, platinum, chromium, tin, or an alloy of any two or more of the above metals. The material of the protective metal layer is aluminum, silver, titanium, nickel, gold, platinum, chromium, tin, tungsten, or an alloy of any two or more of the above metals. Mirror material is silver, aluminum, distributed Bragg reflector. When the light wave of the integrated unit diode chip is UVC, UVB, UVA, violet, blue, green, yellow, and red: the material of the unit diode chip is Al _x1 In _y1 Ga _z1 N, 1≥x1, y1, z1≥0, The substrate is a planar substrate, and the substrate material is sapphire. When the integrated unit diode chip emits yellow light, red light, and infrared light, the material of the unit diode chip is Al _x2 In _y2 Ga _z2 P, 1≥x2, y2, z2≥0, Al _x3 In _y3 Ga _z3 As, 1≥ x3,y3,z3≥0,Al _x4 In _y4 Ga _z4 As _u P _v ,1≥x4,y4,z4,u,v≥0; the substrate is a planar substrate, and the substrate material is indium phosphide.

Since the current diffusion length of the diode chip is inversely proportional to the square root of the current density, under the injection of high current, the current diffusion length is shorter, resulting in more uneven current diffusion of the chip, lower efficiency, and more difficult heat dissipation. The integrated unit light-emitting diode structure design can flexibly change the size and shape of the diode, and can obtain the best current diffusion and heat dissipation performance under the specified working current, and greatly improve the injection current density of the chip, thereby increasing the lumen per unit area output.

Example 2

This embodiment provides an integrated unit diode chip, as shown in FIG. 4 , including: a second conductivity type electrode 1 , a second conductivity type pad 9 and a diode unit 10 . Wherein, the second conductivity type electrode 1 is an n-type electrode, which is composed of a strip-shaped electrode line, and the second conductivity type pad 9 is an n-type pad.

The diode units are squares of the same size, distributed uniformly in 7 rows, 16 columns, and 106, with a length of 40 microns along the Y-axis direction. The diode units are arranged in a rectangle, and the length along the Y-axis direction is smaller than the length of the current diffusion, and the diode units are connected in parallel. A hole structure 11 is added to each diode unit, and there are 212 circular hole units in total. Each diode unit includes two hole units, and the diameter of the hole units is 1 nm to 20 microns. The pore units are arranged symmetrically. The arrangement of hole units can also be asymmetric arrangement, periodic arrangement, non-periodic arrangement or random arrangement, and the shape of hole units can also be triangle, square, rectangle, pentagon, hexagon, circle, and other arbitrary definitions The shape is not limited to the arrangement and shape shown in FIG. 4 . The n-type electrode is a line-shaped electrode line, which adopts a straight line layout. The width of the electrode line is 0.001-10 microns, and the thickness is 0.001-10 microns. The electrode line material is aluminum, silver, titanium, nickel, gold, platinum, chromium, or above. An alloy of any two or more metals.

In some preferred embodiments, the diameter of the diode unit is 10 nanometers; in other preferred embodiments, the diameter of the diode unit is 100 nanometers.

As shown in Figure 5, an integrated unit diode chip also includes a second conductivity type layer 2, a quantum well active region 3, a first conductivity type layer 4, a mirror 5, a protective metal layer 6, a substrate 7, and a back electrode 8. Wherein the second conductivity type layer 2 is an n-GaN layer, and the first conductivity type layer 4 is a p-GaN layer. The back electrode material is aluminum, silver, titanium, nickel, gold, platinum, chromium, tin, or an alloy of any two or more of the above metals. The material of the protective metal layer is aluminum, silver, titanium, nickel, gold, platinum, chromium, tin, tungsten, or an alloy of any two or more of the above metals. Mirror material is silver, aluminum, distributed Bragg reflector. When the light wave of the integrated unit diode chip is UVC, UVB, UVA, violet, blue, green, yellow, and red: the material of the unit diode chip is Al _x1 In _y1 Ga _z1 N, 1≥x1, y1, z1≥0, The substrate is a planar substrate, and the substrate material is sapphire. When the integrated unit diode chip emits yellow light, red light, and infrared light, the material of the unit diode chip is Al _x2 In _y2 Ga _z2 P, 1≥x2, y2, z2≥0, Al _x3 In _y3 Ga _z3 As, 1≥ x3,y3,z3≥0,Al _x4 In _y4 Ga _z4 As _u P _v ,1≥x4,y4,z4,u,v≥0; the substrate is a planar substrate, and the substrate material is indium phosphide.

Since the current diffusion length of the diode chip is inversely proportional to the square root of the current density, under the injection of high current, the current diffusion length is shorter, resulting in more uneven current diffusion of the chip, lower efficiency, and more difficult heat dissipation. The integrated unit light-emitting diode structure design can flexibly change the size and shape of the diode, and can obtain the best current diffusion and heat dissipation performance under the specified working current, and greatly improve the injection current density of the chip, thereby increasing the lumen per unit area output.

The integrated unit light emitting diode provided by the embodiment of the present invention has the following beneficial effects:

(1) The length design of the diode unit of the present invention is controlled within the current diffusion length, and the optimized geometric design with a certain degree of freedom can further improve the light extraction efficiency, and can simultaneously solve the n-type electrode and p The problem of non-uniform current diffusion of type electrodes can be obtained, so as to obtain higher photoelectric conversion efficiency/lumen efficiency.

(2) The design of the integrated unit diode chip of the present invention can realize ultra-uniform current injection, thereby obtaining higher efficiency, better wavelength uniformity, narrower half-width of emission spectrum, and better heat dissipation uniformity and better device stability.

(3) The integrated unit diode chip of the present invention is suitable for LED products of various colors such as UVC, UVA, UVB, purple light, blue light, green light, yellow light, red light, infrared light, etc., and can be used for LED lighting, backlight, display, plant Lighting, medical and other semiconductor light emitting device applications.

The specific embodiments described above have further described the purpose of the present invention, technical solutions and beneficial effects in detail. It should be understood that the above descriptions are only specific embodiments of the present invention and are not intended to limit the protection of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims (21)

1. An integrated unit diode chip, characterized in that, comprising: back electrode, substrate, protective metal layer, mirror, first conductivity type layer, quantum well active region, second conductivity type layer, first conductivity type electrode, second conductivity type electrode, second conductivity type pad and n diode units, the length of the n diode units along the Y-axis direction is less than the current diffusion length, wherein, n≥2; the n diode units shown include a hole structure; the second conductivity type electrode is composed of a linear electrode line ; The line-shaped electrode line adopts a linear layout, and part or all of the design adopts a non-linear layout; there is a mirror between the diode unit and the substrate. 2. An integrated unit diode chip as claimed in claim 1, wherein the non-linear layout includes a broken line layout and a curved layout. 3 . An integrated unit diode chip according to claim 1 , wherein the hole structure comprises 1 to 1,000,000 hole units, and the diameter of the hole units is 0.001 μm to 20 μm. 4. An integrated unit diode chip as claimed in claim 1, characterized in that the reflector material is silver, aluminum or a distributed Bragg reflector. 5. An integrated unit diode chip according to claim 1 or 3, characterized in that the hole units are arranged symmetrically, asymmetrically, periodically, non-periodically or randomly. 6. An integrated unit diode chip as claimed in claim 3, wherein each diode unit contains 1 to 1,000,000 hole units, and the shape of the hole units is triangle, square, rectangle, pentagon, Hexagons, circles, and other arbitrarily defined shapes. 7. An integrated unit diode chip as claimed in claim 1, characterized in that, the connection mode of the diode units is parallel connection, series connection or a combination of series and parallel connection with a set ratio. 8. An integrated unit diode chip as claimed in claim 1, wherein the shape of the diode unit is: triangle, square, rectangle, pentagon, hexagon, circle, any custom shape. 9. An integrated unit diode chip according to claim 1 or 8, characterized in that the number of said diode units is 2-100 billion. 10. An integrated unit diode chip according to claim 1 or 8, characterized in that, the length of the diode unit along the Y-axis direction is 0.001 μm to 100 μm. 11. An integrated unit diode chip according to claim 1 or 9, characterized in that, the diode units are distributed in a uniform and symmetrical arrangement. 12. An integrated unit diode chip according to claim 1 or 9, characterized in that the diode units are of different sizes and arranged in an uneven distribution. 13. A kind of integrated unit diode chip as claimed in claim 1, is characterized in that, described strip-shaped electrode line adopts strip-shaped metal and/or indium tin oxide material; Described strip-shaped metal material is aluminum, silver, titanium , nickel, gold, platinum, chromium, or alloys of any two or more of the above metals. 14. An integrated unit diode chip as claimed in claim 1, wherein the back electrode material is aluminum, silver, titanium, nickel, gold, platinum, chromium, tin, or any two or more of the above Alloys of metals. 15. An integrated unit diode chip as claimed in claim 1, wherein the material of the protective metal layer is aluminum, silver, titanium, nickel, gold, platinum, chromium, tin, tungsten, or any two of the above Alloys of metals and above. 16. An integrated unit diode chip according to claim 1, characterized in that, the material of the reflector is silver, aluminum, or a distributed Bragg reflector. 17. An integrated unit diode chip as claimed in claim 1, characterized in that, the light emitted by the integrated unit diode chip is UVC, UVB, UVA, purple light, blue light, green light, yellow light, red light or infrared light . 18. A kind of integrated unit diode chip as claimed in claim 1, it is characterized in that, when described integrated unit diode chip emits light wave and is UVC, UVB, UVA, purple light, blue light, green light, yellow light or red light, light emitting material Al _x1 In _y1 Ga _z1 N, 1≥x1, y1, z1≥0; the substrate is a planar substrate, or a patterned substrate; the substrate material is sapphire, silicon carbide, gallium nitride, nitride aluminum oxide, gallium oxide, or silicon. 19. An integrated unit diode chip as claimed in claim 1, characterized in that, when the unit diode chip emits light waves of yellow light, red light, and infrared light, the luminescent material is Al _x2 In _y2 Ga _z2 P, 1≥ x2,y2,z2≥0，Al _x3 In _y3 Ga _z3 As，1≥x3,y3,z3≥0,Al _x4 In _y4 Ga _z4 As _u P _v ,1≥x4,y4,z4,u,v≥0 ; The substrate is a planar substrate, or a patterned substrate, and the substrate material is indium phosphide, gallium arsenide, sapphire or silicon. 20. An integrated unit diode chip according to claim 1, characterized in that the size of the integrated unit diode chip is 0.1 micron×0.1 micron to 100000 micron×100000 micron. 21. An integrated unit diode chip according to claim 1, wherein the power of the integrated unit diode chip is 0.0001W˜1000W.