TWI632693B - Light emitting device - Google Patents

Abstract

A light emitting diode device comprising: a light emitting layer comprising a first type semiconductor layer, a second type semiconductor layer and an active layer formed between the first type semiconductor layer and the second type semiconductor layer and emitting a light And a reflective structure formed on the first type semiconductor layer and having a first interface and a second interface, the total reflection angle of the light generated at the first interface is greater than the light generated by the second interface a total reflection angle, and the first type semiconductor layer is electrically connected to the reflective structure through the first interface, and the reflective structure comprises an aperture; and an electrode structure is formed on the second type semiconductor layer, and the aperture system Corresponds to the position of the electrode structure.

Description

Light-emitting diode device

The present invention relates to a light emitting diode device, and more particularly to a light emitting diode device having a void.

Light Emitting Diode (LED) in solid-state light-emitting elements has low power consumption, low heat generation, long operating life, impact resistance, small volume, fast response, and good color light with stable wavelength. Photoelectric characteristics, so it is often used in the fields of home appliances, instrument indicators and optoelectronic products. However, how to improve the luminous efficiency of the light-emitting diode element is still an important issue in this field.

In addition, the above light emitting diode elements may be further combined with a sub-mount to form a light emitting device, such as a light emitting diode package structure. The illuminating device comprises a sub-carrier having at least one circuit; at least one solder is disposed on the sub-carrier, and the illuminating diode is fixed on the sub-carrier by the solder and the substrate of the illuminating diode is The circuit on the secondary carrier forms an electrical connection; and an electrical connection structure electrically connects the electrode pad of the light emitting diode to the circuit on the secondary carrier; wherein the secondary carrier may be a lead frame or A large-sized mounting substrate is used to facilitate the circuit planning of the light-emitting device and improve the heat dissipation effect.

Accordingly, the present invention is directed to a light emitting diode device having apertures.

A light emitting diode device comprising: a light emitting layer comprising a first type semiconductor layer, a second type semiconductor layer and an active layer formed between the first type semiconductor layer and the second type semiconductor layer and emitting a light a reflective structure is formed on the first type semiconductor layer and has a first interface and a second interface, and the total reflection angle of the light generated at the first interface is greater than the total light generated by the light at the second interface a reflection angle, and the first type semiconductor layer is electrically connected to the reflective structure through the first interface, and the reflective structure includes an aperture; and an electrode structure is formed on the second type semiconductor layer, and the aperture system corresponds to At the location of the electrode structure.

The above and other objects, features and advantages of the present invention will become more <RTIgt;

100, 200, 300‧‧‧Lighting diode devices

10‧‧‧Substrate

12‧‧‧Combination structure

121‧‧‧First bonding layer

122‧‧‧Second bonding layer

123‧‧‧ third bonding layer

14‧‧‧Reflective structure

141‧‧‧metal layer

142‧‧‧Transparent conductive layer

143‧‧ ‧ pores

144‧‧‧ first interface

145‧‧‧Second interface

146‧‧‧ third interface

147‧‧‧Contact layer

148‧‧‧ fourth interface

15‧‧‧ sacrificial layer

151, 151', 151" ‧ ‧ patterned sacrificial layer

16‧‧‧Lighting laminate

161‧‧‧First type semiconductor layer

162‧‧‧Active layer

163‧‧‧Second type semiconductor layer

17‧‧‧Protective layer

18‧‧‧second electrode

180‧‧‧electrode pad

181‧‧‧First extension electrode

182‧‧‧Second extension electrode

183‧‧‧ Third extension electrode

19‧‧‧First electrode

20‧‧‧ Growth substrate

21‧‧‧shade

22‧‧‧ lens

23‧‧‧ Carrier

24‧‧‧Lighting module

25‧‧‧ Carrier Board

26‧‧‧Heat components

27‧‧‧Connecting parts

28‧‧‧ circuit unit

30‧‧‧Light bulb

1 is a cross-sectional view of a light emitting diode device in accordance with an embodiment of the present invention.

Fig. 2 is a top plan view of a light emitting diode device in accordance with an embodiment of the present invention.

3A-3E is a cross-sectional view showing the process of manufacturing a light-emitting diode device according to an embodiment of the present invention.

4A-4H is a cross-sectional view showing the process of manufacturing a light-emitting diode device according to another embodiment of the present invention.

5A and 5B are top views of the patterned sacrificial layer and the transparent conductive layer in another embodiment.

Figure 6 is a cross-sectional view showing a light-emitting diode device according to another embodiment of the present invention.

Fig. 7 is a view showing the explosion of the bulb of the light-emitting diode device of the present invention applied to a light bulb.

The present invention will be described with reference to the drawings, in which the same or the same reference numerals are used in the drawings or the description, and in the drawings, the shape or thickness of the elements may be enlarged or reduced. It is to be noted that elements not shown or described in the figures may be in a form known to those skilled in the art.

1 is a cross-sectional view of a light emitting diode device 100 in accordance with an embodiment of the present invention. Referring to FIG. 1 , the LED device 100 includes a substrate 10 , a bonding structure 12 is formed on the substrate 10 , a reflective structure 14 is formed on the bonding structure 12 , and a light emitting layer 16 is formed on the reflective structure 14 . The first electrode 19 is formed on the substrate 10 and a second electrode 18 is formed on the light emitting laminate 16. The bonding structure 12 includes a first bonding layer 121, a second bonding layer 122, and a third bonding layer 123. The reflective structure 14 includes a metal layer 141 formed on the first bonding layer 121, a transparent conductive layer 142 formed on the metal layer 141, and an aperture 143 formed between the transparent conductive layer 142 and the light emitting laminate 16. The light emitting laminate 16 includes a first type semiconductor layer 161, an active layer 162 is formed on the first type semiconductor layer 161 to emit a light, and a second type semiconductor layer 163 is formed on the active layer 162. The first type semiconductor layer 161 and the second type semiconductor layer 163 are, for example, a cladding layer or a confinement layer, and respectively provide electrons and holes to combine electrons and holes in the active layer 162. Glowing. In the present embodiment, the first type semiconductor layer 161 is in direct contact with the transparent conductive layer 142 to have a first interface 144, and the first type semiconductor layer 161 is in direct contact with the aperture 143 to have a second interface 145. The voids 143 are formed in the transparent conductive layer 142 and are not in direct contact with the metal layer 141. Moreover, the refractive index of the aperture 143 is smaller than the refractive index of the transparent conductive layer 142, that is, the refractive index difference between the first type semiconductor layer 161 and the transparent conductive layer 142 is smaller than the refractive index difference between the first type semiconductor layer 161 and the aperture 143. Therefore, when the light emitted by the active layer 162 travels toward the reflective structure 14, the total reflection angle generated at the first interface 144 is greater than the total reflection angle generated by the light at the second interface 145, that is, the light is at the second interface. The probability of total reflection occurring at 145 is greater than the first interface 144. In addition, the first interface 144 of the first type semiconductor layer 161 and the transparent conductive layer 142 are formed. The ohmic contact, while the first type semiconductor layer 161 forms a non-ohmic contact with the second interface 144 of the aperture 143.

Fig. 2 is a top view of the light emitting diode device 100 of the present invention. The cross-sectional view along AA' in Fig. 2 is shown in Fig. 1. In this embodiment, the second electrode 18 has an electrode pad 180, a plurality of first electrode extensions 181, a plurality of second extensions 182, and a plurality of third extensions 183. The plurality of first electrode extensions 181 extend from the electrode pads 180 along the X direction to the left and right sides of the LED device 100 and are arranged in a line; the plurality of second extensions 182 are moved from the electrode pads 180 along the Y direction to the LEDs. The upper and lower sides of the body device 100 extend and are arranged in a straight line and are perpendicular to the first electrode extension portion 181; the third electrode extension portion 183 is physically connected to the second extension portion 182 to form an electrical connection with the electrode pad 180. The third electrode extension portion 183 is parallel to the first electrode extension portion 181, and the first electrode extension portion 181 is located between the plurality of third electrode extension portions 183 and may be the same or different distance from the plurality of third electrode extension portions 183. The lower portions of the first electrode extension portion 181 and the third electrode extension portion 183 are formed in the aperture 143, and the width of the aperture 143 is larger than the width (Y direction) of the first electrode extension portion 181 and the third electrode extension portion 183. No pores 143 are formed under the electrode pads 180. The apertures 143 correspond only to the positions formed at the electrode extensions 181, 183 and extend to both sides of the light emitting diode device 100. In the present embodiment, the first electrode extension portion 181 is not formed below the electrode pad 180 and does not form the aperture 143. The length (X direction) of the aperture 143 corresponding to the lower side of the third electrode extension portion 183 is larger than the length of the third electrode extension portion 183. In another embodiment, the number and arrangement of the electrode extensions can be varied according to actual needs.

In this embodiment, the first type semiconductor layer may be an n-type semiconductor layer and the second type semiconductor layer may be a p-type semiconductor, the first type semiconductor layer and the second type semiconductor layer and include one selected from the group consisting of AlGaAs, AlGaInP, and AlInP. a material in a group of materials composed of InGaP, GaP, and GaAs or a material in a group of materials composed of AlInGaN, InGaN, AlGaN, and GaN; the dopant of the p-type semiconductor includes magnesium, germanium, zinc, carbon, Or a combination thereof; the dopant of the n-type semiconductor comprises germanium, phosphorus, arsenic, antimony or a combination thereof. Alternatively, the first type semiconductor layer may be a p-type semiconductor layer and the second type semiconductor layer may be an n-type semiconductor. The active layer may include one selected from the group consisting of AlGaAs, AlGaInP, AlInP, InGaP, GaP, and GaAs, or one of a group of materials composed of AlInGaN, InGaN, AlGaN, and GaN. The active layer structure may be a single heterostructure (SH), a double heterostructure (DH), a double-side double heterostructure (DDH), or a multi-quantum well (multi-quantum well; MQW). The substrate comprises a material selected from the group consisting of gallium arsenide (GaAs), gallium phosphide (GaP), germanium (Ge), sapphire, glass, diamond, tantalum carbide (SiC), germanium, gallium nitride (GaN), and zinc oxide (ZnO). Substituting at least one of the constituent material groups or other alternative materials. The metal layer can be a single layer or a multilayer structure comprising silver, aluminum, gold, nickel, or a combination thereof. The first bonding layer, the second bonding layer, and the third bonding layer may each be a single layer or a plurality of layers, and comprise a metal or a glue. The metal comprises gold, indium, tin, titanium, platinum, rhodium or a combination thereof. The rubber material comprises benzocyclobutene (BCB), epoxy resin (Epoxy), polydimethyl methoxy oxane (PDMS), yttrium (SiO _x ), alumina (Al ₂ O ₃ ), titanium dioxide (TiO ₂ ), Niobium nitride (SiN _x ), or a combination thereof. The transparent conductive layer may include a metal oxide such as indium tin oxide (ITO), indium oxide (InO), tin oxide (SnO), cadmium tin oxide (CTO), antimony tin oxide (ATO), aluminum zinc oxide (AZO), Zinc oxide oxide (ZTO), gallium zinc oxide (GZO), zinc oxide (ZnO), gallium phosphide (GaP), indium zinc oxide (IZO), diamond-like carbon film (DLC), indium gallium oxide (IGO), oxidation Gallium aluminum zinc (GAZO) or a compound of the above materials. The pores may comprise air, nitrogen, helium, or argon.

3A-3E is a cross-sectional view showing the process of fabricating a light-emitting diode device 100 in accordance with an embodiment of the present invention. Referring to FIG. 3A, a growth substrate 20 (for example, GaAs) is provided, and a light-emitting laminate 16 is epitaxially formed on the growth substrate 20. The light emitting laminate 16 sequentially includes a second type semiconductor layer 163 (for example, AlGaInP), an active layer 162 (for example, AlGaInP), and a first type semiconductor layer 161 (for example, GaP). Referring to FIG. 3B, a sacrificial layer 15 (for example, cerium oxide (SiO ₂ )) is formed on the first type semiconductor layer 161. In another embodiment, the sacrificial layer 15 may also comprise photoresist, tantalum nitride (SiN _x ) or metal (eg, nickel). Referring to FIG. 3C, the sacrificial layer 15 is patterned using a yellow light process to form a patterned sacrificial layer 151. A transparent conductive layer 142 (eg, ITO) is formed on the patterned sacrificial layer 151 and the first type semiconductor layer 161 to coat the patterned sacrificial layer 151 therein. Referring to FIG. 3D, a metal layer 141 (eg, silver) is formed on the transparent conductive layer 142; a first bonding layer 122 and a second bonding layer 123 are formed on the metal layer 141; and a third bonding layer is formed on the substrate 10 (for example) :矽). The substrate 10 is bonded to the metal layer 141 by bonding the second bonding layer 122 and the third bonding layer 123. In another embodiment, the first bonding layer 121 comprises a plurality of layers (eg, Ti/Pt/Au). The Ti layer can serve as a barrier layer to prevent the metal of the metal layer 141 from diffusing to the bonding layer; the Pt layer can be used as an adhesion layer to increase the adhesion between the Ti layer and the Au layer. Referring to FIG. 3E, the patterned sacrificial layer 151 is removed by etching to form the voids 143. The etching may use vapor phase etching or liquid phase etching; the vapor phase etching may include vapor phase hydrogen fluoride; the liquid phase etching may include sodium hydroxide, hydrogen fluoride, ammonium fluoride, or a mixture thereof. After the growth substrate 20 is removed to expose the second type semiconductor layer 163, the first electrode 19 is formed on the substrate 10, and the second electrode 18 is on the second type semiconductor layer 163. The second electrode 18 includes an electrode pad 180 and an extended electrode portion 183. The extended electrode portion 183 corresponds to the position of the aperture 143. In another embodiment, the substrate may be removed prior to etching the patterned sacrificial layer step. It should be noted that when the patterned sacrificial layer 151 is etched by vapor phase etching, since the vapor phase etching does not contain a liquid (for example, water), when the patterned sacrificial layer 151 is removed, the first type semiconductor layer is removed. 161 and the transparent conductive layer 142 are not bonded to each other due to surface tension. Thereby, the patterned sacrificial layer 151 and the aperture 143 have substantially the same shape. Furthermore, the patterned sacrificial layer 151 can have a height of less than 800 Å, that is, the aperture 143 also has a height of less than 800 Å.

4A-4H is a cross-sectional view showing the process of manufacturing the light-emitting diode device 200 in another embodiment of the present invention. The illuminating diode device 200 is similar in structure to the illuminating diode device 100, wherein the same symbols or components, devices or steps corresponding to the symbols have similar or identical components, devices or steps. Referring to FIG. 4A, a growth substrate 20 (for example, GaAs) is provided, and a light-emitting laminate 16 is epitaxially formed on the growth substrate 20. The light emitting laminate 16 sequentially includes a second type semiconductor layer 163 (for example, AlGaInP), an active layer 162 (for example, AlGaInP), and a first type semiconductor layer 161 (for example, GaP). Referring to FIG. 4B, a sacrificial layer 15 (for example, cerium oxide (SiO ₂ )) is formed on the first type semiconductor layer 161. Referring to FIG. 4C, the sacrificial layer 15 is patterned using a yellow light process to form a patterned sacrificial layer 151'. Forming a transparent conductive layer 142 (eg, ITO) on the partially patterned sacrificial layer 151' and the first type semiconductor layer 161, and the transparent conductive layer 142 does not completely cover the patterned sacrificial layer 151' to expose a partial patterning Sacrificial layer 151'. Referring to FIG. 4D, a metal layer 141 is formed on the transparent conductive layer 142. A protective layer 17 is formed to cover the sidewalls of the transparent conductive layer 142 and the metal layer 141 and partially patterned the sacrificial layer 151'. Referring to FIG. 4E, the patterned sacrificial layer 151' is removed by a vapor phase etching method (for example, vapor phase hydrogen fluoride, HF) to form the voids 143. Next, referring to FIG. 4F, after the protective layer 17 is removed, the first bonding layer 121 is formed to cover the sidewalls of the transparent conductive layer 142 and the metal layer 131, whereby the aperture 143 can be formed and buried in the first bonding layer 121. Between the transparent conductive layer 142. The first bonding layer 121 may be a single layer or a plurality of layers. In an embodiment, the first bonding layer 121 comprises a plurality of layers (eg, Ti/Pt/Au). The Ti layer can serve as a barrier layer to prevent the metal of the metal layer 141 from diffusing to the bonding layer; the Pt layer can be used as an adhesion layer to increase the adhesion between the Ti layer and the Au layer.

Referring to FIG. 4G, the substrate 10 (eg, germanium) is bonded to the light emitting laminate 16 by the first bonding layer 121, the second bonding layer 122, and the third bonding layer 123. Referring to FIG. 4H, after the growth substrate 20 is removed, the first electrode 19 is formed on the substrate 10 and the second electrode 18 is formed on the second semiconductor layer 163. In this embodiment, the second electrode 18 does not correspond to the location of the aperture 143. The first type semiconductor layer 161 is in direct contact with the transparent conductive layer 142 to have a first interface 144. The first type semiconductor layer 161 is in direct contact with the aperture 143 to have a second interface 145 and the first type semiconductor layer 161 is combined with the first layer. Layer 121 has a third interface 146. The pores 143 are also not in direct contact with the metal layer 141. Moreover, the refractive index of the aperture 143 is smaller than the refractive index of the transparent conductive layer 142 and the first bonding layer 121, that is, the refractive index difference between the first type semiconductor layer 161 and the transparent conductive layer 142 is smaller than that of the first type semiconductor layer 161 and the aperture 143. The refractive index difference and the refractive index difference between the first type semiconductor layer 161 and the first bonding layer 121 are smaller than the refractive index difference between the first type semiconductor layer 161 and the aperture 143. Therefore, when the light emitted by the active layer 162 travels toward the reflective structure 14, the total reflection angle of the light generated by the first interface 144 and the third interface 146 is greater than that of the second light. The total reflection angle generated by the interface 145, that is, the probability that the light is totally reflected at the second interface 145 is greater than the first interface 144 and the third interface 146. It should be noted that when the light emitted by the active layer 162 is blue light (wave peak is about 430 nm to 480 nm), the refractive index of the first bonding layer 121 for blue light is smaller than that of the transparent conductive layer, for example, when the first bonding layer 121 is Ti or Pt. When the transparent conductive layer is ITO, the first bonding layer 121 has a refractive index of about 1.6-1.9, and the transparent conductive layer has a refractive index of about 2.0-2.3. That is, the total reflection angle generated by the blue light at the first interface 144 is greater than the total reflection angle generated by the light at the third interface 146, that is, the probability of total reflection of the light at the third interface 146 is greater than the first interface 144. When the light emitted by the active layer 162 is red light (wave peak is about 630 nm to 670 nm), the refractive index of the first bonding layer 121 for red light is greater than the refractive index 142 of the transparent conductive layer, for example, when the first bonding layer 121 is Ti or Pt, when the transparent conductive layer is ITO, the first bonding layer 121 has a refractive index of about 2.0 to 2.3, and the transparent conductive layer has a refractive index of about 1.7 to 1.9. The total reflection angle generated by the red light at the third interface 146 is greater than the total reflection angle generated by the light at the first interface 144, that is, the probability of total reflection of the light at the first interface 144 is greater than the third interface 146. When the light emitted by the active layer 162 is blue or red, the refractive index of the aperture 143 is approximately one. In addition, the first type semiconductor layer 161 forms an ohmic contact with the first interface 144 of the transparent conductive layer 142; the first type semiconductor layer 161 forms a non-ohmic contact with the second interface 144 of the aperture 143; and the first type semiconductor layer 161 and the A third interface 146 of a bonding layer 121 forms a non-ohmic contact.

5A and 5B are views showing a top view of the patterned sacrificial layer 151' and the transparent conductive layer 142 of the light emitting diode device 200. Referring to FIG. 5A, the patterned sacrificial layer 151' includes a plurality of elongated structures, and the transparent conductive layer 142 is formed on the elongated structure and covers a portion of the elongated structure. Referring to FIG. 5B, the patterned sacrificial layer 151" includes a plurality of elongated strip structures perpendicular to each other to form a grid-like structure. The transparent conductive layer 142 is also formed on the grid-like structure and covers a portion of the grid. In one embodiment, the area ratio of the surface area of the patterned sacrificial layer 151', 151" to the surface area of the first type semiconductor layer 161 is between 10% and 90%, or between 50% and 90%. However, the area, shape, and number of the patterned sacrificial layers 151', 151" can be varied according to actual needs. The surface area of the transparent conductive layer 142 and the first type semiconductor The area ratio of the surface area of layer 161 is between 10% and 90%, or between 10% and 50%.

Figure 6 is a cross-sectional view showing a light emitting diode device 300 in another embodiment of the present invention. The illuminating diode device 300 is similar in structure to the illuminating diode device 200, wherein the same symbols or components, devices or steps corresponding to the symbols have similar or identical components, devices or steps. In this embodiment, the LED device 300 further includes a contact layer 147 formed between the transparent conductive layer 142 and the first type semiconductor 161 to facilitate current dispersion. The contact layer 147 is covered or embedded in the transparent conductive layer 142 and is not in direct contact with the metal layer 141. The first type semiconductor layer 161 is in direct contact with the contact layer 147 to have a fourth interface 148 and form an ohmic contact. Contact layer 147 can comprise a metal or an alloy. The metal may comprise copper, aluminum, indium, tin, gold, platinum, zinc, silver, titanium, nickel, lead, palladium, or chromium; the alloy may comprise bismuth-gold, bismuth-gold, chromium-gold, silver-titanium, copper - tin, copper-zinc, copper-cadmium, tin-lead-tin, tin-lead-zinc, nickel-tin, or nickel-cobalt.

Fig. 7 is a view showing the explosion of a light bulb of a light-emitting diode device of the present invention applied to a light bulb. The light bulb 30 includes a lamp cover 21, a lens 22, a light emitting module 24, a carrier 25, a heat dissipating component 26, a connecting member 27, and a circuit unit 28. The light module 24 includes a carrier 23 and a plurality of light emitting devices. The illumination device can be any of the above-described light-emitting diode devices 100 (200, 300). As shown in FIG. 7, for example, 12 illuminating devices are located on the carrier 23, wherein the six red illuminating devices and the six blue illuminating devices are staggered and electrically connected to each other (can be connected in series, in parallel or in a bridge) ). The blue light emitting device may include a phosphor powder disposed thereon to convert light emitted by the blue light emitting device. The light emitted by the blue light emitting device is mixed with the converted light to form a white light, and is matched with the red light emitting device to cause the bulb 30 to emit a warm white light having a color temperature of 2400-3000K.

The examples of the invention are intended to be illustrative only and not to limit the scope of the invention. Any obvious modifications or variations of the present invention are possible without departing from the spirit and scope of the invention.

Claims (10)

A light emitting diode device comprising: a light emitting layer comprising a first type semiconductor layer, a second type semiconductor layer and an active layer formed between the first type semiconductor layer and the second type semiconductor layer and emitting a light a reflective structure is formed on the first type semiconductor layer and has a first interface and a second interface, and the total reflection angle of the light generated at the first interface is greater than the total light generated by the light at the second interface a reflection angle, and the first type semiconductor layer is electrically connected to the reflective structure through the first interface, and the reflective structure includes an aperture; and an electrode structure is formed on the second type semiconductor layer, and the aperture system corresponds to At the location of the electrode structure. The light emitting diode device of claim 1, wherein the reflective structure comprises a transparent conductive layer, and the first interface is located between the first type semiconductor layer and the transparent conductive layer. The light emitting diode device of claim 2, wherein the second interface is between the first type semiconductor layer and the aperture. The light emitting diode device of claim 3, wherein the reflective structure comprises a metal layer in contact with the transparent conductive layer. The light-emitting diode device of claim 4, wherein the aperture is not in contact with the metal layer. The light-emitting diode device of claim 1, wherein the pores comprise air, nitrogen, helium or argon. The light emitting diode device of claim 1, further comprising a contact layer formed between the reflective structure and the first type semiconductor layer. The light-emitting diode device according to claim 1, wherein the profile is In view, the aperture has a width greater than the width of the electrode structure. The illuminating diode device of claim 1, further comprising a bonding layer covering the reflective structure, wherein the bonding layer is in contact with the first type semiconductor layer. A light emitting diode device comprising: a light emitting layer comprising a first type semiconductor layer, a second type semiconductor layer and an active layer formed between the first type semiconductor layer and the second type semiconductor layer and emitting a light And a reflective structure formed on the first type semiconductor layer and having a first interface and a second interface, the total reflection angle of the light generated at the first interface is greater than the light generated by the second interface a total reflection angle, and the first type semiconductor layer is electrically connected to the reflective structure through the first interface, and the reflective structure comprises a metal layer, a hole and a transparent conductive layer, wherein the hole is not in contact with the metal layer And the metal layer is in contact with the transparent conductive layer.