TWI458142B - Wire bonding structure - Google Patents

Description

Wire bonding structure

The present invention relates to a wire bonding structure, and more particularly to a wire bonding structure for a conductive and light transmissive transparent wire.

Light-Emitting Diode (LED) has the advantages of long life, small size, low heat generation and low power consumption. In the past, the light-emitting diode was applied to an indicator light or a small light source. In recent years, due to the development of multi-color and high-brightness of light-emitting diodes, the application range of light-emitting diodes has been extended to large-scale outdoor display billboards and traffic lights, and traditional light sources have been gradually replaced by light-emitting diodes. It is a source of lighting that has both power saving and environmental protection functions.

Please refer to FIG. 1 , which illustrates a schematic diagram of a conventional surface mount type LED package structure. The LED package structure 100 includes a light-emitting element 101, a carrier 102, an encapsulant 130, a transparent colloid 140, and two gold wires 110 and 120. The light emitting element 101 is disposed in a recess 132 of the encapsulant 130 and is located on the carrier 102. The carrier 102 includes a wafer holder 103 and two pins 104, 105. The light-emitting element 101 is disposed on the wafer holder 103 and electrically connected to the two pins 104 and 105 through the two gold wires 110 and 120. In addition, the two pins 104 and 105 respectively pass through the encapsulant 130 and extend out of the recess 132 and are electrically connected to the substrate 150 through the solder 152 to receive a current. Therefore, the light-emitting element 101 can be electroluminescent by the current received by the two pins 104, 105. In addition, the transparent colloid 140 is filled in the recess 132 and covers the light emitting element 101, the two gold wires 110, 120, the wafer holder 103, and the two pins 104, 105 exposed in the recess 132.

However, the use of gold wire to conduct the input current, due to cost and absorbance considerations, the wire diameter of the gold wire used is not too large, often causing many application problems and limitations. For example, if a binary transparent colloid (solid and liquid) is used, the difference in thermal expansion coefficient (CTE) between the interfaces causes the gold wire to be broken and broken. If a transparent colloid with good water repellency is used, it is usually accompanied by a high coefficient of thermal expansion, so the product failure is often caused by the hot and cold cycle test.

The present invention relates to a wire bonding structure in which a transparent wire having a conductive property and a light transmissive property is used in place of a conventionally used gold wire.

According to an aspect of the invention, a wire bonding structure is proposed for electrically connecting an electronic component and a carrier. The electronic component has a first electrode and the carrier has a first conductive support. Characterized in that the wire bonding structure comprises a first transparent wire. The first transparent wire is electrically connected between the first electrode and the first conductive support.

According to an embodiment of the invention, the electronic component further has a second electrode, and the carrier further has a second conductive support. The wire bonding structure further includes a second transparent wire electrically connected between the second electrode and the second conductive support.

In order to better understand the above and other aspects of the present invention, the preferred embodiments are described below, and in conjunction with the drawings, the detailed description is as follows:

The wire bonding structure of this embodiment replaces the conventionally used gold wire with a transparent wire having a conductive property, and can improve the tensile strength of the wire. The increase in tensile strength reduces the probability of interruption of the process and avoids breakage of the wire due to pulling. In addition, since the material of the transparent wire itself is translucent, it is possible to improve the phenomenon that the amount of light emitted by the gold wire is reduced.

The following is a detailed description of various embodiments, which are intended to be illustrative only and not to limit the scope of the invention.

First embodiment

Please refer to FIG. 2, which is a schematic diagram of a wire bonding structure according to an embodiment of the invention. For example, the surface-bonding structure includes a first transparent conductive line 210 and a second transparent conductive line 220 for electrically connecting an electronic component 201 and a carrier 203. The electronic component 201 is, for example, a light emitting diode or other integrated circuit wafer having a first electrode 202 and a second electrode 208. The carrier 203 is, for example, a metal substrate having a first conductive support 204 and a second conductive support 205. The first electrode 202 of the electronic component 201 is electrically connected to the first conductive bracket 204 through the first transparent wire 210. The second electrode 208 is electrically connected to the second conductive bracket 205 through the second transparent wire 220.

In an embodiment, the electronic component 201 is disposed in the recess 232 of the encapsulant 230 and is located on the carrier 203. In addition, the transparent colloid 240 is filled in the recess 232 and covers the electronic component 201, the first and second transparent wires 210, 220, and the first and second conductive supports 204, 205 exposed in the recess 232.

Please refer to FIG. 3, which is a partially enlarged schematic view showing a transparent wire according to an embodiment of the invention. Taking the transparent wire in the area A of FIG. 2 as an example, the transparent wire 210 is a wire core 214 having a transparent conductive layer 212 formed on the surface. The wire core material 214 may be an organic wire core material, an inorganic wire core material, or an organic-inorganic hybrid wire core material. The transparent conductive layer 212 is formed, for example, by magnetron sputtering, pulsed laser deposition, arc discharge ion plating, or reactive evaporation. By using the vacuum coating technology described above and the adjustment of the process parameters, a transparent conductive layer 212 having extremely low resistivity and high light transmittance, such as indium tin oxide (ITO), antimony tin oxide (ATO), and zinc indium oxide, can be obtained. (IZO), zinc oxide (ZnO), carbon nanotubes (CNT) or conductive polymers.

The conductive polymer may include Polyaniline (polyaniline, PANI), Poly (3,4-ethylenedioxythiophene) (poly 3,4-ethylenedioxythiophene, PEDOT), Polypyrrole (polypyrrole, PPY) or a derivative thereof.

In addition, the organic wire core material 214 may include epoxy resin, silicone rubber, acrylic (PMMA) resin or polyethylene terephthalate (PET). The inorganic wire core material 214 may include a material such as tantalum nitride or hafnium oxynitride. Since these wire core members 214 are light transmissive, the wire diameter of the wire core member 214 can be increased without affecting the light transmittance. Further, the thicker the wire diameter, the stronger the tensile strength, so that the tensile strength of the wire core member 214 can be increased by increasing the wire diameter of the wire core member 214.

Regardless of the surface of the organic wire core material, the inorganic wire core material or the organic-inorganic hybrid wire core material, the transparent conductive layer 212 can be formed by the vacuum coating technique described above to make the transparent wire 210 conductive. In addition, the transparent conductive wire 210 may also be added with a nano conductive material to improve its conductivity, for example, a conductive material such as a carbon nanotube is added to the high molecular material to reduce surface resistance and increase electrical conductivity.

Second embodiment

Please refer to FIG. 4, which is a schematic diagram of a wire bonding structure according to an embodiment of the invention. Taking the gallium arsenide LED 301 as an example, it includes an upper electrode 302, a semiconductor material layer 306, an illuminating epitaxial layer 307, and a lower electrode 308. The upper electrode 302 is disposed on the semiconductor material layer 306 over the luminescent epitaxial layer 307 to form an ohmic contact. In addition, the upper electrode 302 is electrically connected to the first conductive bracket 304 through a transparent wire 310 to receive a current. The lower electrode 308 is electrically connected to the second conductive bracket 305. Therefore, the current injected by the upper electrode 302 can flow through the luminescent epitaxial layer 307 by uniform current diffusion, so that the luminescent epitaxial layer 307 generates a photoelectric effect to emit light.

In this embodiment, the upper electrode 302 and the lower electrode 308 may be transparent conductive electrodes, and the material thereof includes indium tin oxide (ITO), antimony tin oxide (ATO), zinc indium oxide (IZO), and zinc oxide (ZnO). ) or nickel gold alloy. In addition, as shown in FIG. 3, the transparent wire 310 may be a wire core 214 having a transparent conductive layer 212 formed on its surface. Since the upper electrode 302, the lower electrode 308, and the transparent wiring 310 have high light transmittance, the phenomenon that the amount of light emission is lowered can be improved.

The method for fabricating the transparent conductive layer 212 and the selection of materials have been specifically described in the first embodiment, and are not described herein again. It should be noted that, although the encapsulant and the transparent colloid are not shown in this embodiment, the LED 301 of the present embodiment is disposed in the recess 232 of the encapsulant 230 of FIG. 2 and is located on the carrier 203. It is conceivable to fill the recess 232 with the transparent colloid 240 and cover the light-emitting diode 301 and the transparent lead 310 exposed in the recess 232.

Third embodiment

Please refer to FIG. 5, which is a schematic diagram of a wire bonding structure according to an embodiment of the invention. For example, the GaN LED 401 includes a first electrode 402, a first semiconductor material layer 406, a luminescent epitaxial layer 407, a second semiconductor material layer 409, and a second electrode 408. The first electrode 402 is disposed on the first semiconductor material layer 406 above the luminescent epitaxial layer 407 to form an ohmic contact. The first electrode 402 is electrically connected to the first conductive bracket 404 through the first transparent conductive line 410 to receive a current. In addition, the second electrode 408 is disposed on the second semiconductor material layer 409 under the luminescent epitaxial layer 407 to form an ohmic contact. The second electrode 408 is electrically connected to the second conductive bracket 405 through the second transparent wire 420. Therefore, the current injected by the first electrode 402 can flow through the luminescent epitaxial layer 407 by uniform current diffusion, so that the luminescent epitaxial layer 407 generates a photoelectric effect to emit light.

In this embodiment, the first electrode 402 and the second electrode 408 may be transparent conductive electrodes, and the material thereof includes indium tin oxide (ITO), antimony tin oxide (ATO), zinc indium oxide (IZO), and zinc oxide. (ZnO) or nickel gold alloy. In addition, as shown in FIG. 3, the first and second transparent wires 410, 420 may be wire cores 214 having a transparent conductive layer 212 formed on the surface. Since the first electrode 402, the second electrode 408, and the first and second transparent wires 410 and 420 have high light transmittance, the phenomenon that the amount of light emission is lowered can be improved.

The method for fabricating the transparent conductive layer 212 and the selection of materials have been specifically described in the first embodiment, and are not described herein again. It should be noted that, although the encapsulant and the transparent colloid are not shown in the embodiment, the LED 401 of the embodiment is disposed in the recess 232 of the encapsulant 230 of FIG. 2 and is located on the carrier 203. It is conceivable that the transparent colloid 240 is filled in the recess 232 and covers the light-emitting diode 401 and the first and second transparent wires 410 and 420 which are exposed in the recess 232.

The wire bonding structure disclosed in the above embodiments of the present invention replaces the conventionally used gold wire with a transparent wire having a conductive property, and can improve the tensile strength of the wire. The increase in tensile strength reduces the probability of interruption of the process and avoids breakage of the wire due to pulling. In addition, since the material of the transparent wire itself is translucent, it is possible to improve the phenomenon that the amount of light emitted by the gold wire is reduced. Also, since the core material of the transparent wire can be an organic or inorganic material, the coefficient of thermal expansion is low, and the coefficient of thermal expansion of the transparent colloid can be matched, so that different transparent colloids can be freely selected, thereby improving the freedom of use of the transparent colloid.

In conclusion, the present invention has been disclosed in the above preferred embodiments, and is not intended to limit the present invention. A person skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, the scope of the invention is defined by the scope of the appended claims.

100. . . Light emitting diode package structure

101. . . Light-emitting element

102. . . Carrier

103. . . Wafer holder

104, 105. . . Pin

110, 120. . . Gold Line

130. . . Encapsulant

132. . . Groove

140. . . Transparent colloid

150. . . Substrate

152. . . solder

200. . . Chip package structure

201. . . Electronic component

202, 402. . . First electrode

203. . . Carrier

204, 304, 404. . . First conductive bracket

205, 305, 405. . . Second conductive bracket

208, 408. . . Second electrode

210, 410. . . First transparent wire

212. . . Transparent conductive layer

214. . . Wire core material

220, 420. . . Second transparent wire

230. . . Encapsulant

232. . . Groove

240. . . Transparent colloid

301. . . GaAs light-emitting diode

302. . . Upper electrode

306. . . Semiconductor material layer

307. . . Luminescent epitaxial layer

308. . . Lower electrode

310. . . Transparent wire

401. . . Gallium nitride light-emitting diode

406. . . First semiconductor material layer

407. . . Luminescent epitaxial layer

409. . . Second semiconductor material layer

A. . . region

FIG. 1 is a schematic view showing a conventional surface-adhesive LED package structure.

FIG. 2 is a schematic view showing a wire bonding structure according to an embodiment of the invention.

FIG. 3 is a partially enlarged schematic view showing a transparent wire according to an embodiment of the invention.

4 is a schematic view showing a wire bonding structure according to an embodiment of the present invention.

FIG. 5 is a schematic view showing a wire bonding structure according to an embodiment of the present invention.

200. . . Chip package structure

201. . . Electronic component

202. . . First electrode

203. . . Carrier

204. . . First conductive bracket

205. . . Second conductive bracket

208. . . Second electrode

210. . . First transparent wire

220. . . Second transparent wire

230. . . Encapsulant

232. . . Groove

240. . . Transparent colloid

A. . . region

Claims (10)

A wire bonding structure for electrically connecting an electronic component and a carrier, the electronic component having a first electrode, the carrier having a first conductive support, wherein the wire bonding structure comprises: a first transparent wire And electrically connected between the first electrode and the first conductive support, wherein the first transparent conductive wire is an organic wire core material, an inorganic wire core material or an organic-inorganic hybrid wire core material having a transparent conductive layer formed on the surface. The wire bonding structure according to claim 1, wherein the electronic component is a gallium antimonide light emitting diode. The wire bonding structure of claim 1, wherein the electronic component further has a second electrode, the carrier further comprising a second conductive support, wherein the wire bonding structure further comprises: a second transparent The wire is electrically connected between the second electrode and the second conductive support. The wire bonding structure according to claim 3, wherein the electronic component is a gallium nitride light emitting diode. The wire bonding structure according to claim 1 or 3, wherein the first electrode and the second electrode are transparent conductive electrodes, and the material thereof comprises indium tin oxide (ITO), antimony tin oxide (ATO), Zinc indium oxide (IZO), zinc oxide (ZnO) or nickel gold alloy. The wire bonding structure according to claim 3, wherein the second transparent wire is an organic wire core material, an inorganic wire core material or an organic-inorganic hybrid wire core material having a transparent conductive layer formed on the surface. a wire bonding structure as described in claim 6 of the patent application, The material of the organic wire core material includes epoxy resin, silicone rubber, acrylic (PMMA) resin or polyethylene terephthalate (PET). The wire bonding structure according to claim 6, wherein the material of the inorganic wire core material comprises tantalum nitride or hafnium oxynitride. The wire bonding structure according to claim 6, wherein the transparent conductive layer comprises indium tin oxide (ITO), antimony tin oxide (ATO), zinc indium oxide (IZO), and zinc oxide (ZnO). ), carbon nanotubes or conductive polymers. The wire bonding structure according to claim 9, wherein the conductive polymer comprises Polyaniline, Poly (3,4-ethylenedioxythiophene) or Polypyrrole.