TWI669834B - Optoelectronic device and method for manufacturing the same - Google Patents

Abstract

A photovoltaic device comprising: a semiconductor stack, wherein the semiconductor stack comprises a first semiconductor layer, a light emitting layer is over the first semiconductor layer, and a second semiconductor layer is above the light emitting layer; a first electrode is located Above the second semiconductor layer, wherein the first electrode further comprises a reflective layer; and an insulating layer is formed on the second semiconductor layer, and the first electrode has a spacing from the insulating layer.

Description

Photoelectric element and method of manufacturing same

This invention relates to a photovoltaic element, and more particularly to an electrode design for a photovoltaic element.

The principle of light-emitting diode (LED) is to use energy difference between the n-type semiconductor and the p-type semiconductor to release energy in the form of light. This principle of illumination is different from incandescent lamps. The principle of heat generation, so the light-emitting diode is called a cold light source. In addition, the light-emitting diode has the advantages of high durability, long life, light weight, low power consumption, etc., so the current lighting market has high hopes for the light-emitting diode, and it is gradually replaced as a new generation of lighting tools. Light source, and is used in various fields, such as traffic signs, backlight modules, street lighting, medical equipment, etc.

1A is a schematic view showing the structure of a conventional light-emitting element. As shown in FIG. 1A, a conventional light-emitting element 100 includes a transparent substrate 10, a semiconductor laminate 12 on a transparent substrate 10, and at least one electrode 14 located in the semiconductor. On the stack 12, the semiconductor stack 12 includes at least a first conductive semiconductor layer 120, an active layer 122, and a second conductive semiconductor layer 124 from top to bottom.

1B is a schematic view showing the structure of a conventional light-emitting element electrode. As shown in FIG. 1B, a conventional light-emitting element 100' includes a transparent substrate 10, a semiconductor laminate 12 on the transparent substrate 10, and at least one electrode 14 is located. The semiconductor layer 12 may include a reflective electrode 141 and a diffusion barrier layer 142. However, since the diffusion barrier layer 142 may not transmit light, the light-emitting efficiency of the light-emitting element 100 is lowered.

In addition, the above-described light-emitting element 100 can be further combined with other elements to form a light-emitting apparatus. 2 is a schematic view showing the structure of a conventional light-emitting device. As shown in FIG. 2, a light-emitting device 200 includes a sub-mount 20 having at least one circuit 202; at least one solder 22 is located in the above-mentioned sub-carrier 20, the light-emitting element 100 is bonded and fixed to the secondary carrier 20 by the solder 22, and the substrate 10 of the light-emitting element 100 is electrically connected to the circuit 202 on the secondary carrier 20; and an electrical connection structure 24 is The electrode 14 of the light-emitting element 100 and the circuit 202 on the secondary carrier 20 are electrically connected; wherein the secondary carrier 20 can be a lead frame or a large mounting substrate to facilitate the circuit of the light-emitting device 200. Plan and improve its cooling performance.

A photovoltaic device comprising: a semiconductor stack, wherein the semiconductor stack comprises a first semiconductor layer, a light emitting layer is over the first semiconductor layer, and a second semiconductor layer is above the light emitting layer; a first electrode is located Above the second semiconductor layer, wherein the first electrode further comprises a reflective layer; and an insulating layer is formed on the second semiconductor layer, and the first electrode has a spacing from the insulating layer.

The present invention discloses a light-emitting element and a method of manufacturing the same. In order to make the description of the present invention more detailed and complete, please refer to the following description and the drawings of FIGS. 3A to 6 .

3A to 3E are schematic views showing the structure of a manufacturing process according to an embodiment of the present invention. As shown in FIG. 3A, a substrate 30 is provided, and then a semiconductor epitaxial layer 32 is formed on the substrate 30, wherein the semiconductor epitaxial stack The layer 32 includes a first conductive semiconductor layer 321, an active layer 322, and a second conductive semiconductor layer 323 from bottom to top.

Next, an insulating layer 34 is formed on the semiconductor epitaxial layer 32, and is in direct contact with the first surface 3211 of the first conductive semiconductor layer 321 and the first surface 3231 of the second conductive semiconductor layer 323. Thereafter, a patterned photoresist layer 36 is formed over the first surface 34S of the insulating layer 34, and a portion of the insulating layer first surface 34S is exposed.

As shown in FIG. 3B, an insulating process is performed on the insulating layer 34 by the patterned photoresist layer 36, and a portion of the insulating layer 34 is removed, and a portion of the first surface of the first conductive semiconductor layer 321 is exposed. a portion of the first surface 3231 of the second conductive semiconductor layer 323 is formed on the first surface 3211 of the first conductive semiconductor layer 321 and a second insulating layer 342 is formed on the second surface. A portion of the first surface 3231 of the conductive semiconductor layer 323, and a third insulating layer 343 over a portion of the first surface 3231 of the second conductive semiconductor layer 323 and a portion of the first surface of the first conductive semiconductor layer 321 Above 3211.

In one embodiment, the insulating layer 34 can be etched by the patterned photoresist layer 36 so that the insulating layer 34 partially under the patterned photoresist layer 36 is also etched, even if part of the first The insulating layer 341 and the second insulating layer 342 have an undercut shape with respect to the patterned photoresist layer 36. The patterned photoresist layer 36 thus has a pitch G at the edge projected onto the surface of the semiconductor epitaxial layer 32 and projected onto the edge of the surface of the semiconductor epitaxial layer 32 by the first insulating layer 341 and the second insulating layer 342. In an embodiment, the pitch G may be less than 3 μm. In an embodiment, the side etch may be a wet etch.

Next, as shown in FIG. 3C, a first metal layer 382, a second metal layer 381, and a temporary metal layer 383 are simultaneously formed by physical vapor deposition. The first metal layer 382 is formed on a portion of the first surface 3231 exposed by the second conductive semiconductor layer 323; the second metal layer 381 is formed on a portion of the first surface 3211 exposed by the first conductive semiconductor layer 321 And a temporary metal layer 383 is formed on the patterned photoresist layer 36 and covers the upper surface of the patterned photoresist layer 36. In one embodiment, the physical vapor deposition may be vacuum evaporation, sputtering, electron beam evaporation, or ion plating.

In an embodiment, since the patterned photoresist layer 36 has an undercut shape, the sidewalls of the first metal layer 382 do not directly contact the sidewalls of the third insulating layer 343 and the second insulating layer 342. The sidewalls of the second metal layer 381 are not in direct contact with the sidewalls of the first insulating layer 341 and the third insulating layer 343.

In one embodiment, the first metal layer 382 can be a plurality of layers and can include a reflective layer, the material of which can be selected from materials having a reflectance greater than 90%. In one embodiment, the material of the reflective layer in the first metal layer may be selected from the group consisting of chromium (Cr), titanium (Ti), nickel (Ni), platinum (Pt), copper (Cu), gold (Au), aluminum ( Metal materials such as Al), tungsten (W), tin (Sn), or silver (Ag).

Next, as shown in FIG. 3D, the patterned photoresist layer 36 and the temporary metal layer 383 thereon are removed. In an embodiment, as shown in FIG. 3D, the first surface 3211 of the second metal layer 381 to the first conductive semiconductor layer 321 may have a height h1, and the first insulating layer 341 to the first conductive semiconductor layer The first surface 3211 of the 321 may have a height h2. The second metal layer 381 and the first insulating layer 341 may have a similar height or a difference in height between the second metal layer 381 and the first insulating layer 341 by the above process of the present invention. Less than 1 μm. In an embodiment, the second metal layer 381 and the first insulating layer 341 may have a pitch d1, and the pitch d1 is less than 3 μm, and/or the second metal layer 381 and the third insulating layer 343 may have a pitch d2. And this spacing d2 is less than 3 μm. In an embodiment, d1 and d2 may have the same value.

In another embodiment, the first surface 3231 of the first metal layer 382 to the second conductive semiconductor layer 323 may have a height h3, and the first surface 3231 of the second insulating layer 342 to the second conductive semiconductor layer 323 There may be a height h4. The first metal layer 382 and the second insulating layer 342 may have similar heights or the height difference between the first metal layer 382 and the second insulating layer 342 may be less than 1 μm by the process disclosed in the above embodiments. In an embodiment, the first metal layer 382 and the second insulating layer 342 may have a pitch d3, and the pitch d3 is less than 3 μm, and/or the first metal layer 382 and the third insulating layer 343 may have a pitch d4. And this spacing d4 is less than 3 μm. In an embodiment, d3 and d4 may have the same value. In another embodiment, d1, d2, d3, and d4 may have the same value.

Finally, as shown in FIG. 3E, a third metal layer 42 is formed over the first metal layer 382, and a fourth metal layer 40 is formed over the second metal layer 381 to complete the photovoltaic element 300 of the present invention. In one embodiment, a portion of the fourth metal layer 40 is in direct contact with the first surface 3211 of the first conductive semiconductor layer 321, or a portion of the third metal layer 42 is in direct contact with the first surface 3231 of the second conductive semiconductor layer 323. . In an embodiment, the second insulating layer 342 is hardly present under the third metal layer 42. In another example, the top of the third metal layer 42 has a shortest distance d6 from the second surface 3212 of the first semiconductor layer 321, and the top of the fourth metal layer 40 and the second surface 3212 of the first semiconductor layer 321 have A shortest distance d5, and the difference between d6 and d5 is less than 1 μm. In an embodiment, the projections of the third metal layer 42 and the fourth metal layer 40 in the normal direction of the vertical substrate 30 may have similar areas.

In an embodiment, after the 3D or 3E is continued, the substrate 30 can be removed and a portion of the second surface 3212 of the first conductive semiconductor layer 321 is exposed to form a thin film-thin film. Flip chip). In an embodiment, after the 3D or 3E is continued, the photovoltaic element 300 of the present invention can be used by the first metal layer 382 and the second metal layer 381 or the third metal layer 42 and the fourth metal layer 40. It is connected to a carrier (not shown) to form a flip chip package. In one embodiment, the material of the first metal layer 382, the second metal layer 381, the third metal layer 42 or the fourth metal layer 40 includes, but is not limited to, copper (Cu), aluminum (Al), indium (In), tin. (Sn), gold (Au), platinum (Pt), zinc (Zn), silver (Ag), titanium (Ti), nickel (Ni), lead (Pb), palladium (Pd), germanium (Ge), chromium (Cr), cadmium (Cd), cobalt (Co), manganese (Mn), antimony (Sb), antimony (Bi), gallium (Ga), antimony (Tl), antimony (Po), antimony (Ir), antimony (Re), rhodium (Rh), strontium (Os), tungsten (W), lithium (Li), sodium (Na), potassium (K), bismuth (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), zirconium (Zr), molybdenum (Mo), sodium (La), silver-titanium (Ag-Ti), copper-tin (Cu-Sn), copper-zinc (Cu-Zn) , Cu-Cd, Tin-Pb-Sb, Sn-Pb-Zn, Ni-Sn, Ni-Sn, Ni -Co), gold alloy (Au alloy), or bismuth-gold-nickel (Ge-Au-Ni) and other metal materials.

4A to 4C are schematic views showing a light emitting module, and FIG. 4A is a perspective view showing an external light emitting module. The light emitting module 500 can include a carrier 502, a plurality of lenses 504, 506, and 508. 510, and two power supply terminals 512 and 514.

4B-4C is a cross-sectional view showing a light emitting module, wherein FIG. 4C is an enlarged view of the E region of FIG. 4B. The carrier 502 can include an upper carrier 503 and a download body 501, wherein a surface of the download body 501 can be in contact with the upper carrier 503. Lenses 504 and 508 are formed over upper carrier 503. The upper carrier 503 can form at least one through hole 515, and the light emitting diode element 300 formed according to the embodiment of the present invention can be formed in the through hole 515 and in contact with the download body 501, and surrounded by the rubber material 521. There is a lens 508 above the glue 521.

As shown in FIG. 4C, in one embodiment, a reflective layer 519 may be formed on both sidewalls of the via 515 to increase light extraction efficiency; a metal layer 517 may be formed on the lower surface of the download body 501 to improve heat dissipation efficiency.

5A-5B is a schematic diagram 600 of a light source generating device 600. A light source generating device 600 can include a light emitting module 500, a housing 540, and a power supply system (not shown) for supplying a current to the light source generating device 600. And a control element (not shown) for controlling the power supply system (not shown). The light source generating device 600 can be a lighting device, such as a street light, a car light or an indoor lighting source, or a backlight source of a traffic sign or a backlight module in a flat display.

Figure 6 is a schematic view of a light bulb. The light bulb 700 includes a housing 921, a lens 922, a lighting module 924, a bracket 925, a heat sink 926, a series of junctions 927 and an electrical connector 928. The illumination module 924 includes a carrier 923 and includes at least one of the LED components 300 of the above embodiment on the carrier 923.

Specifically, the photovoltaic element 300 includes a light emitting diode (LED), a photodiode, a photoresistor, a laser, an infrared emitter, and an organic light emitting diode. At least one of (organic light-emitting diode) and solar cell. The substrate 30 is a growth and/or carrier foundation. The candidate material may comprise a conductive substrate or a non-conductive substrate, a light transmissive substrate or an opaque substrate. One of the conductive substrate materials may be germanium (Ge), gallium arsenide (GaAs), indium phosphate (InP), tantalum carbide (SiC), germanium (Si), lithium aluminate (LiAlO ₂ ), zinc oxide (ZnO). ), gallium nitride (GaN), aluminum nitride (AlN), metal. One of the transparent substrate materials may be sapphire, lithium aluminate (LiAlO2), zinc oxide (ZnO), gallium nitride (GaN), glass, diamond, CVD diamond, and diamond-like carbon (Diamond-Like Carbon; DLC), spinel (MgAl ₂ O ₄ ), alumina (Al ₂ O ₃ ), cerium oxide (SiO _X ), and lithium gallate (LiGaO ₂ ).

The first conductive semiconductor layer 321 and the second conductive semiconductor layer 323 are different in electrical conductivity, polarity, or dopant, and are used to provide a single or multi-layer structure of a semiconductor material for electrons and holes, respectively ("multilayer" refers to Two or more layers, the same as below.) The electrical selection may be a combination of at least any two of p-type, n-type, and i-type. The active layer 322 is located between the two portions of the electrical, polar or dopant, or between the semiconductor materials for providing electrons and holes, respectively, for the conversion of electrical energy and light energy or induced conversion. region. Those who convert or induce light energy are such as light-emitting diodes, liquid crystal displays, and organic light-emitting diodes; those that convert or induce light energy are such as solar cells and photodiodes. The above-mentioned semiconductor epitaxial layer 32 has a material containing one or more elements selected from the group consisting of gallium (Ga), aluminum (Al), indium (In), arsenic (As), phosphorus (P), nitrogen (N), and antimony ( Si) is a group. Commonly used materials are such as Group III nitrides such as aluminum gallium indium phosphide (AlGaInP) series and aluminum gallium indium nitride (AlGaInN) series, and zinc oxide (ZnO) series. The structure of the active layer 322 is, for example, a single heterostructure (SH), a double heterostructure (DH), a double-side double heterostructure (DDH), or a multi-layer quantum well (multi- Quantum well; MQW) structure. When the photovoltaic element 300 is a light-emitting diode, its light-emitting spectrum can be adjusted by changing the physical or chemical elements of the semiconductor single layer or multiple layers. Furthermore, adjusting the logarithm of the quantum well can also change the wavelength of the illumination.

In an embodiment of the invention, the semiconductor epitaxial layer 32 and the substrate 30 may optionally include a buffer layer (not shown). The buffer layer is interposed between the two material systems to "transition" the material system of the substrate to the material system of the semiconductor system. For the structure of the light-emitting diode, on the one hand, the buffer layer is used to reduce the material layer of the lattice mismatch between the two materials. On the other hand, the buffer layer may also be a single layer, a plurality of layers or a structure for combining two materials or two bifurcation structures, such as organic materials, inorganic materials, metals, and semiconductors; The selected structure is: reflective layer, thermally conductive layer, conductive layer, ohmic contact layer, anti-deformation layer, stress release layer, stress adjustment layer, bonding layer, wavelength Conversion layer, mechanical fixing structure, etc.

A contact layer (not shown) is more selectively formed on the semiconductor epitaxial laminate 32. The contact layer is disposed on one side of the semiconductor epitaxial layer 32 facing the substrate 30. In particular, the contact layer can be an optical layer, an electrical layer, or a combination of both. The optical layer can alter the electromagnetic radiation or light from or into the active layer. As used herein, "change" refers to altering at least one optical property of electromagnetic radiation or light, including but not limited to frequency, wavelength, intensity, flux, efficiency, color temperature, rendering index, light field. (light field), and angle of view. The electrical layer may cause at least one of the voltage, resistance, current, and capacitance of the opposite side of the contact layer to change or change in value, density, or distribution. The constituent material of the contact layer comprises an oxide, a conductive oxide, a transparent oxide, an oxide having a transmittance of 50% or more, a metal, a relatively light-transmissive metal, a metal having a transmittance of 50% or more, an organic substance, At least one of an inorganic substance, a phosphor, a phosphor, a ceramic, a semiconductor, a doped semiconductor, and an undoped semiconductor. In some applications, the material of the contact layer is at least one of indium tin oxide, cadmium tin oxide, antimony tin oxide, indium zinc oxide, zinc aluminum oxide, and zinc tin oxide. In the case of a relatively light-transmitting metal, the thickness thereof is preferably about 0.005 μm to 0.6 μm. In one embodiment, the contact layer has a preferred lateral current spreading rate that can be used to assist in the uniform diffusion of current into the semiconductor epitaxial stack 32. Generally, the impurities blended according to the contact layer vary depending on the manner of the process, and the width of the energy gap may be between 0.5 eV and 5 eV.

The above figures and descriptions are only corresponding to specific embodiments, however, the elements, embodiments, design criteria, and technical principles described or disclosed in the various embodiments are inconsistent, contradictory, or difficult to implement together. In addition, we may use any reference, exchange, collocation, coordination, or merger as required. Although the invention has been described above, it is not intended to limit the scope of the invention, the order of implementation, or the materials and process methods used. Various modifications and variations of the present invention are possible without departing from the spirit and scope of the invention.

100,100’‧‧‧Lighting elements

200‧‧‧Lighting device

202‧‧‧ Circuitry

20‧‧‧subcarriers (sub-mount)

22‧‧‧Solder

24‧‧‧Electrical connection structure

10‧‧‧Transparent substrate

12‧‧‧Semiconductor laminate

14‧‧‧Electrode

141‧‧‧Reflective electrode

142‧‧‧Diffusion barrier

120,321‧‧‧First Conductive Semiconductor Layer

122,322‧‧‧active layer

124,323‧‧‧Second conductive semiconductor layer

300‧‧‧Lighting diode components

30‧‧‧Substrate

32‧‧‧Semiconductor epitaxial stack

34‧‧‧Insulation

341‧‧‧First insulation

342‧‧‧Second insulation

343‧‧‧ Third insulation layer

3211‧‧‧ First surface of the first conductive semiconductor layer

3231‧‧‧ First surface of the second conductive semiconductor layer

36‧‧‧ patterned photoresist layer

34S‧‧‧ first surface

G‧‧‧ spacing

382‧‧‧First metal layer

381‧‧‧Second metal layer

383‧‧‧ Temporary metal layer

42‧‧‧ Third metal layer

40‧‧‧fourth metal layer

500‧‧‧Lighting Module

502‧‧‧ Carrier

504, 506, 508, 510‧‧ lens

512, 514‧‧‧ power supply terminal

503‧‧‧carrier

501‧‧‧Download

515‧‧‧through hole

517‧‧‧metal layer

519‧‧‧reflective layer

600‧‧‧Light source generating device schematic

700‧‧‧Light bulb

921‧‧‧ Shell

922‧‧‧ lens

923‧‧‧ Carrier

924‧‧‧Lighting module

925‧‧‧ bracket

926‧‧‧ radiator

927‧‧‧ tandem

928‧‧‧Electrical connector

1A-1B is a structural diagram showing a side view of a conventional array of light emitting diode elements;

Figure 2 is a schematic view showing the structure of a conventional light-emitting device;

3A-3E are schematic structural diagrams of a manufacturing process according to an embodiment of the present invention;

4A to 4C are schematic views showing a light emitting module;

5A-5B are schematic views showing a light source generating device; and

Figure 6 is a schematic view of a light bulb.

Claims (10)

A photovoltaic device comprising: a semiconductor stack, wherein the semiconductor stack comprises a first semiconductor layer, a light emitting layer is on the first semiconductor layer, and a second semiconductor layer is above the light emitting layer; a metal layer is disposed on the second semiconductor layer; a second metal layer is disposed on the first semiconductor layer; and an insulating layer includes a first insulating layer, a second insulating layer and a third insulating layer. A sidewall of the first metal layer and a sidewall of the insulating layer have a spacing d3 or a spacing d4, and a sidewall of the second metal layer and a sidewall of the insulating layer have a sidewall a pitch d1 or a pitch d2, wherein a top of the first metal layer to a top of the second semiconductor layer has a height h3, and a top of the second insulating layer has a height to the top of the second semiconductor layer H4, and the difference between the height h3 and the height h4 is less than 1 μm, and wherein a top of the second metal layer to a top of the first semiconductor layer has a height h1, and one of the first insulating layers is topped to the first Semiconductor layer The top has a height h2, and the difference between the height h1 and the height h2 is less than 1 μm. The photovoltaic device of claim 1, further comprising a third metal layer on the first metal layer and the insulating layer, wherein the third metal layer comprises a portion of the sidewall of the first metal layer Between the sidewall of the insulating layer. The photovoltaic device according to claim 2, further comprising a fourth metal layer on the second metal layer and the insulating layer. The photovoltaic element according to claim 3, wherein the third insulating layer is located on a surface of a portion of the second semiconductor layer and over a surface of a portion of the first semiconductor layer, and the third insulating layer is the third metal The layer and the fourth metal layer are partially covered. The photovoltaic device of claim 3, wherein a top of the third metal layer has a shortest distance d6 from a surface of the first semiconductor layer, and one of the fourth metal layer is topped to the first semiconductor layer The surface has a shortest distance d5, the difference between the shortest distance d6 and the shortest distance d5 being less than 1 μm. The photovoltaic device of claim 3, wherein the fourth metal layer comprises a portion between the sidewall of the second metal layer and the sidewall of the insulating layer. The photovoltaic device of claim 3, wherein the fourth metal layer is above the first semiconductor layer and the second semiconductor layer, and the fourth metal layer comprises a portion in direct contact with the second metal layer . The photovoltaic element according to claim 1, wherein the first metal layer comprises a reflective layer, and the material of the reflective layer may be selected from the group consisting of chromium (Cr), titanium (Ti), nickel (Ni), and platinum (Pt). ), metal materials such as copper (Cu), gold (Au), aluminum (Al), tungsten (W), tin (Sn), or silver (Ag). The photovoltaic element according to claim 1, wherein the pitch d1, the pitch d2, the pitch d3 or the pitch d4 is less than 3 μm. The photovoltaic device of claim 1, wherein the second insulating layer and the third insulating layer are located on opposite sides of the first metal layer, and the first insulating layer and the third insulating layer are located at the first Two sides of the two metal layers.