TWI521742B - Flip-chip light emitting diode package module and manufacturing method thereof - Google Patents

Description

Flip-chip type light emitting diode package module and manufacturing method thereof

The invention provides a light emitting diode package module and a manufacturing method thereof, in particular to a flip chip type light emitting diode module and a manufacturing method thereof.

Conventional LED chip packaging requires the use of a ceramic substrate as an LED package carrier, so that the thermal energy generated by the LED conducts thermal energy of the wafer to the circuit board by excellent thermal conductivity of the carrier. Please refer to FIG. 1 for the LED chip. 10' is fixed on the ceramic substrate 12' by using a solid glue 11', and is covered with a sealing material 18'. The substrate 12' is fixed to a metal-based printed circuit board (MCPCB) composed of an aluminum plate 15' and an insulating layer 14' by solder 13'. The structural design is used to conduct heat generated by the LED wafer 10' in the direction of the arrow.

Therefore, in the conventional LED chip package structure, the top-down layer inspection is sequentially performed as a light-emitting diode die, a die bond, a substrate, a solder, and a printed circuit board. However, most of the layer structure means that there is a majority of the layer thermal resistance, that is, the characteristics of the thermal impedance increase due to the increase in the thickness of the LED chip package structure, which causes heat dissipation problems, so the conventional LED chip emits light. The heat dissipation effect of the diode package structure is not ideal, and there are also cost considerations. However, in the trend of light-emitting diodes, it is bound to develop in the direction of low thermal resistance, low cost and process simplification. In addition to the chipmaker's design to reduce thermal resistance and cost, this must also be included in the LED chip package. There is a breakthrough in development.

In summary, the present inventors have felt that the above problems can be improved, and they have devoted themselves to research and cooperate with the application of the theory, and finally proposed a present invention which is reasonable in design and effective in improving the above-mentioned defects.

The main object of the present invention is to provide a flip-chip type light emitting diode module and a manufacturing method thereof, which are methods for reducing a substrate and simplifying the manufacturing process of the solid crystal wire bonding process.

In order to achieve the above object, the present invention provides a method for manufacturing a flip-chip type LED package module, which comprises the steps of: providing a carrier body on which a plurality of light emitting diode chips are disposed; a plastic process for forming a plurality of transparent packages corresponding to and covering the LED chips, the peripheral edges of the transparent packages collectively forming a side wing, and the flip-chip LED package structure is formed by the side wing Connecting to each other; performing a separate process to form a plurality of flip-chip LED structures without the carrier; and performing a bonding process to bond at least one flip-chip LED structure On a circuit board.

The present invention also provides a flip-chip LED package module, comprising: a circuit substrate having a plurality of electrical connection pads; and a flip-chip LED package structure directly disposed on the circuit substrate The flip-chip LED package structure includes a light emitting diode chip having a surrounding side surface and a first surface and a second surface, the side surface and the first surface and the surface The second surface is coupled to the second surface, the second surface has at least one pair of wafer metal pads, the at least one pair of wafer metal pads have a spacing gap, and a transparent package encircling the light emitting diode chip The side surface, the first surface and the second surface fill the gap, wherein the at least one pair of wafer metal pads are electrically connected to the corresponding electrical connection pads, the bottom surface of the transparent package and the circuit substrate Separation.

The present invention omits by directly bonding a light emitting diode wafer to a circuit substrate. The substrate between the light-emitting diode chip and the circuit substrate in the conventional technology can effectively solve the heat dissipation problem of the light-emitting diode package module, and simplify the manufacturing process and reduce the number of layers of the structure stack. Achieve cost reduction. In addition, the flip-chip LED package structure taken out by the self-supporting body itself is characterized by a separate component, and can be mass-produced by using a fully automated Surface Mount Technology (SMT), thereby greatly reducing Manufacturing and labor costs.

For a better understanding of the features and technical aspects of the present invention, reference should be made to the accompanying drawings.

"Knowledge Technology"

10’LED‧‧‧ wafer

11'‧‧‧Solid glue

12'‧‧‧Substrate

13’‧‧‧Solder

14'‧‧‧Insulation

15'‧‧‧Aluminum sheet

18’‧‧‧Packaging materials

"this invention"

Step S102 to step S108

100‧‧‧Flip-chip LED package module

1‧‧‧ circuit substrate

11‧‧‧Electrical connection pads

11a‧‧‧Top

12‧‧‧ solder mask

2‧‧‧Light Emitter Wafer

21‧‧‧ side surface

22‧‧‧ first surface

23‧‧‧ second surface

24‧‧‧ wafer metal pad

24a‧‧‧Contact points

241‧‧‧P type contact pad

242‧‧‧N type contact pad

25‧‧‧ sidewall protection

26‧‧ ‧ mirror layer

27‧‧‧P type semiconductor laminate

28‧‧‧N type semiconductor laminate

29‧‧‧Substrate

3‧‧‧Transparent package

31‧‧‧ bottom

31a‧‧‧ inside bottom

31b‧‧‧Outer bottom

32‧‧‧Flanking

32a‧‧‧ bottom

33‧‧‧Contact surface

200‧‧‧Carrier

201‧‧‧ cutting road

202‧‧‧Upper surface

300‧‧‧Flip-chip LED package structure

400‧‧‧Fluorescent materials

500‧‧‧ solder

Central axis of S1‧‧‧ transparent package

Central axis of S2‧‧‧ light-emitting diode chip

P‧‧‧ interval gap

W‧‧‧Thin wall thickness

Thickness of H1‧‧‧Light Emitting Diode Wafer

Thickness of H2‧‧‧ flanks

L‧‧‧Dimensions of LED Diode Wafers

R‧‧‧Linear distance

C‧‧‧ center point

Q‧‧‧ openings

AA‧‧‧ wafer spacing

BB‧‧‧ wafer diagonal length

CC‧‧‧ wafer spacing

Θ‧‧‧ angle

1 is a schematic diagram of a conventional LED chip package; FIG. 2A is a flow chart of a method for manufacturing a flip-chip type LED package module according to the present invention; FIG. 2B is a manufacturing process of the flip-chip type LED package module of the present invention; Method flow chart (2); FIG. 3A is a schematic view of a light-emitting diode wafer disposed on a carrier of the present invention; FIG. 3B is a side view of the light-emitting diode chip disposed on the carrier of the present invention; FIG. 3C is a portion A of FIG. 4A is a schematic view showing a transparent package formed on a light-emitting diode wafer according to the present invention; FIG. 4B is a side view showing a transparent package formed on the light-emitting diode wafer of the present invention; Figure 6 is a perspective view of a single flip-chip LED package structure of the present invention; Figure 7 is a cross-sectional view of a single flip-chip LED package structure of the present invention; Figure 8 is a single flip of the present invention Side view of a light-emitting diode package structure; FIG. 9A is a geometrical schematic diagram of a flip-chip light-emitting diode structure on a carrier of the present invention; FIG. 9B is a flip-chip light-emitting diode structure on the carrier body of the present invention; Geometric diagram (2); 10A is a schematic view (1) of the present invention after the bonding process is heated; FIG. 10B is a schematic view (2) of the present invention after the bonding process is heated; FIG. 11A is a schematic view showing a coating process of the present invention; and FIG. A schematic diagram of the doping process.

The embodiments described below are referred to by the number or the like, and the scope of application of the invention should not be limited by the number or the like unless otherwise stated. The manufacturing method of the flip-chip LED package module of the present invention is suitable for directly bonding a light-emitting diode wafer to a printed circuit board (PCB), a metal core printed circuit board (MCPCB), ceramics The substrate (Ceramic SUB) and the copper-clad ceramic substrate (Direct Bond Cu, DBC) are not limited to the scope of application of the present invention.

As shown in FIG. 2A to FIG. 5, in the embodiment, the flip-chip LED package module 100 of the present invention is manufactured, and the plurality of LED chips 2 disposed on the carrier 200 are integrally formed. After sizing, the dicing is further performed to form a single flip-chip LED package structure 300 including a light-emitting diode chip 2 and a transparent package 3 (FIG. 6).

Referring to FIG. 2A to FIG. 10 , FIG. 2A is a flow chart (1) of a method for manufacturing the flip-chip LED package module 100 of the present invention. In this embodiment, as described in step S102, a carrier 200 having a predetermined dicing street 201 (shown in FIG. 5) is provided. Preferably, the carrier 200 is provided as a flexible film, such as a blue film. (Blue Tape), UV film (UV Tape), film or rigid carrier plate, etc., the material of the carrier 200 is not limited to the above; wherein, the cutting channel 201 can also be formed into a transparent process in the subsequent sealing process. The package 3 (shown in Figure 5) is detailed later. 3A is a schematic view of a light-emitting diode chip disposed on a carrier of the present invention, and FIG. 3B is a side view of FIG. 3A. In this embodiment, a plurality of light-emitting diode chips are arranged in an array. 2 is on the carrier 200; in addition, the carrier 200 can also have the characteristics of single-sided or double-sided adhesion, so that the LED 2 can be directly disposed on the adhesive property. On the surface of the carrier, the function of temporary fixing of the wafer can be simultaneously provided for subsequent processes; and each of the LED chips 2 has a surrounding side surface 21 and a first surface 22 and a second surface. 23, and the side surface 21 is respectively engaged with the first surface 22 and the second surface 23, and further, as shown in FIG. 3C is an enlarged view of the portion A in FIG. 3B, the side surface 21 is preferably further formed with a side wall. A protective layer 25 such as yttrium oxide (SiOx) or aluminum oxide is used to reduce damage of the light-emitting diode chip 2 due to subsequent packaging processes. The second surface 23 of each of the light-emitting diode chips 2 has at least one pair of wafer metal pads 24, and at least one pair of wafer metal pads 24 has a spacing gap P. In fact, at least one pair of wafer metal pads 24 can be respectively P-contact pad 241 and N-contact pad 242, the sidewall protection layer 25 can further extend onto the second surface 23, that is, formed on the P-type contact pads 241 and N. The insulating layer between the contact pad 242 and the LED chip 2 respectively provides at least one opening Q to the corresponding P-type semiconductor laminate 27 and the N-type semiconductor laminate 28, so that the P-type contact pad 241 and the N-type The contact pads 242 are electrically connected to the corresponding P-type semiconductor stack 27 and the N-type semiconductor stack 28 through the corresponding openings Q, and the P-type contact pads 241 and the N-type contact pads 242 have the insulating layer thereon. The PN is effectively insulated, and the subsequent process of the P-type contact pads 241 and the N-type contact pads 242 can be reduced, because of the structure of the adjacent P-type semiconductor stack 27 and the N-type semiconductor stack 28 (e.g., pitch, The difference in height, etc.) causes the yield of the conductive junction structure (P-type contact pad 241 and N-type contact pad 242) to be poor. In addition, it can be clearly seen that the insulating layer can have a mirror layer 26 (such as ITO+silver or sterling silver) under the insulating layer, which can be located above the P-type semiconductor stack, and the P-type contact pad 241 is in contact with the N-type. Below the corresponding projecting position of the pad 242, the surface area is slightly smaller than the P-type semiconductor laminate 27 to effectively increase the brightness.

In addition, the light-emitting diode chips 2 are adhered to the upper surface of the carrier 200 in a flip chip manner, wherein the contact points between the upper surface 202 of the carrier 200 and the P-type contact pads are formed. The distance between 24a is the same as the distance between the contact point 24a of the N-type contact pad, and it can be said that the three have a horizontal plane.

Thereafter, as described in step S104, a glue process can be performed to form a plurality of transparent packages 3 corresponding to and covering the light-emitting diode wafers 2. In the encapsulation process, please refer to FIG. 4A and FIG. 4B. In this embodiment, the LED chips 2 are packaged by Molding to form a plurality of flip-chip LED packages connected to each other. Structure 300. In the present invention, the light-emitting diode chips 2 can also be packaged by a molding method such as mixing, dispensing, or the like to form a plurality of flip-chip type LED package structures 300.

Further, the carrier 200 is first placed in a molding die (not shown), and the molding die has a plurality of cavities (not shown), and the cavities are respectively corresponding to the two illuminations. Polar body wafer 2. In the embodiment, the cavity pre-forming system is in the shape of a sphere, and the preforms of the cavity may also be arc-shaped, drop-shaped, square, dish-shaped or pyramid-shaped, and the shape of the cavity is not It is defined that different cavity shapes will form transparent packages 3 of different shapes, and then liquid transparent glues are injected into the mold holes, the depths of the mold holes being greater than the height of the light-emitting diode chips 2. It is noted that, referring to FIG. 4B, a side view of forming a transparent package on the LED of the present invention has a shortest distance W (ie, a flank) between the cavity (not shown) and the carrier 200. The thickness of the portion 32 is W), and the outward contact point 24a of any two of the wafer metal pads 24 is coplanar with the upper surface 202 of the carrier 200, so that the liquid transparent glue can flow unimpeded between the two wafer metal pads 24 to fill The gap P is filled, that is, the liquid transparent glue surrounds the two wafer metal pads 24 so that the liquid transparent glue completely covers the periphery of the LED 2; more specifically, the liquid is transparent. The glue is completely coated on the surrounding side surface 21, the first surface 22, and the second surface 23 of the light-emitting diode wafer 2, and is integrated with the light-emitting diode wafer 2. It should be noted that the liquid transparent adhesive mainly covers the first surface 22 (the main light-emitting surface) and the surrounding side surface 21, and the liquid transparent adhesive covers the second surface 23, so that the liquid transparent adhesive can completely and firmly grasp the whole. The light-emitting diode chip 2 is not easy to fall off. In addition, the liquid transparent adhesive may also form the uncured side flaps 32 between the light-emitting diode wafers 2 such that the light-emitting diode wafers 2 are connected to each other by the un-hardened side flaps 32.

Then, a heating and baking step can be performed to harden the liquid transparent glue. The transparent package 3 is coated on the periphery of each of the LED chips 2, and the plurality of transparent package 3 arrays are respectively corresponding to the LED chips 2; preferably, The bottom surface 31 of the transparent package 3 includes an inner bottom surface 31a and an outer bottom surface 31b. The inner bottom surface 31a and the outer bottom surface 31b are equal and coplanar, and the inner bottom surface 31a and the outer bottom surface 31b are contoured to the upper surface 202 of the carrier 200. The contact surface 33 of the transparent package 3 covering the LED chip 2 is respectively contoured to the surrounding side surface 21, the first surface 22 and the second surface 23 of the LED wafer 2. At this time, since the plurality of side wing portions 32 are formed together by the peripheral edges of the plurality of transparent packages 3, the flip-chip type LED package structures 300 can be connected to each other by the side wing portions 32. In the embodiment, the bottom surface 32a of the side wing portions 32 (ie, the bottom surface 3 of the transparent package 3), the contact point 24a of the wafer metal pad 24, and the upper surface 202 of the carrier 200 are coplanar. However, the above is only one of the modes of the embodiment, and is not limited to this mode of operation. It should be noted that in the above sealing process, a tunnel may be formed on the side flaps 32 between the transparent packages 3 to serve as the cutting path 201 (FIG. 5).

In this embodiment, the transparent package 3 may be a silicone, a thermosetting colloid or an epoxy resin, but the material of the transparent package 3 is not limited to the above, and the transparent package 3 formed is a hemisphere. The shape, however, the shape of the transparent package 3 is not limited herein. The transparent transparent package 3 after curing has a light transmittance T of more than 60% with respect to the light-emitting transparent body 3 of a wavelength range of 300 nm to 950 nm emitted from the light-emitting diode wafer 2, and is relative to the light-emitting diode The light transmittance T of the transparent package 3 of the wavelength range of 450 nm to 660 nm emitted by the wafer 2 is greater than 90%; wherein T is defined as the light intensity I of the transmitted substance and the light intensity I ₀ incident on the substance. The ratio, that is, the transmittance T = I / I ₀ . In addition, if the light-emitting diode chip 2 has a sidewall protective layer 25 (as shown in FIG. 3C), such as yttria or aluminum oxide, the refractive index of the transparent package 3 is preferably close to or smaller than the sidewall protective layer 25 based on the light extraction efficiency. The refractive index, for example, if the refractive index of the transparent package 3 is 1.5, the refractive index of the sidewall protective layer 25 may be 1.45 cerium oxide or 1.65 aluminum oxide; more specifically, the transparent package When the refractive index of 3 is k, the refractive index of the sidewall protective layer 25 is suggested to be 0.95 k to 1.15 k. That is to say, the light emitted by the LED chip 2 is expected to directly penetrate the sidewall transparent layer 25 (as shown in FIG. 3C) and the transparent package 3 adjacent thereto, thereby effectively reducing the interlayer effect and the loss of light.

The invention covers the light-emitting diode chip 2 by the transparent package 3, thereby achieving the effect of protecting the light-emitting diode chip 2, avoiding the influence of external temperature, moisture and noise, and effectively improving weather resistance and machinery. strength. In addition, the transparent package 3 also has an optical function. For example, the transparent package 3 can be designed with different variations, including a convex shape, a concave shape or a planar shape to generate different optical effects, respectively. The light concentration, the light dispersion, or the uniform light can be achieved, thereby increasing the variability of the light-emitting pattern of the light-emitting diode wafer 2, and improving the brightness and luminous efficiency of the light-emitting diode wafer 2. More specifically, since the present invention can be directly packaged on the LED 2 through the transparent package 3 and integrated with the LED 2, it is compared with the conventional LED. The lens 2 is further provided with a lens, and is condensed by a multiple optical interface (secondary lens) to enhance the illuminance. The present invention can efficiently converge the LED 2 through a single optical interface (primary lens). All the light emitted can not only effectively reduce the light loss, but also avoid the problem of the joint between the conventional LED chip 2 and the external lens.

Then, as described in step S106, after the transparent package 3 is bonded to the LED 2, a separation process can be performed. Referring to FIG. 5, FIG. 5 is a schematic diagram of the separation process of the present invention, in the separation process. Using a cutting tool along the cutting path 201 on the carrier 200, the cutting track 201 on the side wing portion 32 between the transparent packages 3, or a cutting positioning plate (not shown) surrounding the periphery of the carrier 200 The dicing street 201 cuts the side flaps 32 between the transparent packages 3, so that the flip-chip LED package structure 300 is removed from the carrier 200, thereby forming a single single as shown in FIG. A flip-chip LED package structure 300. In more detail, the scribe line 201 is defined in such a manner that the position of the dicing street 201 is preset on the carrier 200, and since the transparent package 3 or the carrier 200 is transparent or translucent State, so it can be easily identified for cutting. In addition, the position of the dicing street 201 can be defined between the transparent package 3 during the sealing process, so that the cutting path 201 between the transparent package 3 and the transparent package 3 can be along the cutting process. The flank portion 32 is cut. In addition to this, the separation process can also be divided directly between the transparent packages 3 by means of stamping. However, the manner in which the separation process is used is not limited to the above. It should be noted that, referring to FIG. 7 , a plurality of single flip-chip LED package structures 300 obtained by the separation process may be completely covered by the transparent diode 3 formed by hardening. The periphery of the wafer 2 (including the wafer metal pad 24) is filled with the gap P, and the bottom surface 31 of the transparent package 3 is coplanar with the contact point 24a of the wafer metal pad 24, so that the transparent package 3 can be firmly secured by the contact surface 33. Grasping the periphery of the LED chip 2 (such as the surrounding side surface 21, the first surface 22 and the second surface 23), and not easily degumming, so that the single flip-chip LED package structure 300 can be reused Further applications are arranged in an array or surface light source mode.

On the other hand, in the plurality of single flip-chip LED package structures 300 obtained by the separation process, since the transparent package 3 has a spherical shape, the pattern cut by the carrier 200 is rectangular, so the geometry is The relationship causes each of the flip-chip LED packages 300 to leave a portion of the side wings 32. Considering that the light emitted by the LED chip 2 is not shielded by the side flaps 32 and affects the luminous efficiency and brightness, please refer to FIG. 8 for a transparent package of a single flip-chip LED package structure according to the present invention. In the above sealing process, the central axis S1 of the cured transparent package 3 is coaxial with the central axis S2 of the LED 2, and the thickness W of the side portions 32 is expressed by the following equation. It is determined that: H1 < W < H2, H2 = R × sin θ, tan θ = H1/(L / 2), wherein H1 is the thickness of the light-emitting diode wafer 2, and L is the size of the light-emitting diode wafer 2. R is a linear distance from the center point C of the second surface 23 to the first surface 22 through the side surface 21 and extends to the surface of the transparent package 3, where θ is R and the bottom surface 31 of the transparent package 3 Angle.

On the other hand, referring to FIG. 9A and FIG. 9B, considering the geometric factor when performing the cutting, the wafer pitch of the LED 2 on the carrier 200 is It will be related to the type of flip-chip LED package structure 300 that is fabricated. As shown in FIG. 9A, when the flip-chip LED package structure 300 is a lens type (Lens-Type), considering that the transparent package 3 is spherical, each of the two LEDs is located on the carrier 200. The predetermined pitch AA of the wafers between the wafers 2 is greater than or equal to 40% of the length of the diagonal BB of each of the LED chips 2, so as to smoothly cut out the single flip-chip LED package structure 300. purpose. As shown in FIG. 9B, considering that the transparent package 3 is equal to the adjacent side flaps 32, for example, the transparent packages 3 are square (ie, the peripheral edges of the transparent package 3 are respectively Corresponding to and parallel to the peripheral edge of the LED chip 2, the wafer preset spacing CC between each two LED wafers 2 on the carrier 200 must be greater than 0.1 mm to leave a gap for the laser. Can cut smoothly.

Finally, as shown in step S108, a bonding process is performed. Please refer to FIG. 10A and FIG. 10B. FIG. 10A is a schematic view (1) of the bonding process heating process of the present invention, and FIG. 10B is a schematic view of the bonding process of the present invention. (2) The flip-chip LED package module 100 of the present invention is completed by bonding at least one flip-chip LED package structure 300 to a circuit substrate 1; The bottom surface 31 of the transparent package 3 of the LED package structure 300 is separated from the circuit substrate 1. In this embodiment, the circuit substrate 1 may be an aluminum substrate (MCPCB), or may be a ceramic substrate, a germanium substrate or a glass fiber substrate. However, the material of the circuit substrate 1 is not limited to the above. More specifically, the flip-chip LED package structure 300 of the present invention is bonded to the circuit substrate 1 by directly soldering the wafer metal pad 24 of the second surface 23 of the LED body 2 by soldering the solder. The electrical connection pads 11 on the circuit board 1 are joined to each other and electrically connected. For example, as shown in FIG. 10A, when the package solder is solder 500, the bonding process of the present invention is an SMT (Surface Mount Technology) process, in which the electrical connection pad 11 of the circuit substrate 1 is placed in the solder 500. And the flip-chip LED package structure 300 is placed on the circuit substrate 1, and then through the Reflow process, that is, the circuit substrate 1 is placed in a high temperature furnace to heat the solder 500, and the solder can be completed. Mounted light two a process of bonding the metal pad 24 of the polar package structure 300 to the electrical connection pad 11 of the circuit substrate 1; wherein the material of the solder 500 may be gold, nickel, tin, gold tin alloy, silver tin alloy, gold alloy or Indium, etc.

In addition, in this embodiment, since the area of the wafer metal pad 24 is greater than or equal to the area of the electrical connection pad 11, when the solder is packaged using the solder 500, the wafer metal pad 24 is at the same pitch (pad pitch). The pad width of the electrical connection pad 11 is reduced, that is, the space between the adjacent electrical connection pads 11 is increased, so that the solder 500 can be prevented from contacting each other due to diffusion during the soldering process, resulting in a short circuit or solder 500. Uneven conditions occur. In addition, since the top surface 11a of the electrical connection pad 11 is higher than the solder resist layer 12 of the circuit substrate 1, it is possible to effectively avoid the occurrence of a short circuit caused by the solder 500 flowing to the circuit substrate 1 due to the extrusion diffusion during the soldering process. .

In addition, as shown in FIG. 10B, when the package solder is a flux (not labeled), the bonding process of the present invention is to place the flip-chip LED package structure 300 on the circuit substrate 1 and on the wafer metal pad. A flux is placed between the 24 and the electrical connection pads 11, and then the circuit board 1 is placed in a high temperature furnace for heating. Through the action of the flux, the wafer metal pad 24 and the electrical connection pad 11 can achieve the effect of soldering. During the heating process, the flux will volatilize. After heating, the flux will not exist between the wafer metal pad 24 and the electrical connection pad 11, in other words, since the wafer metal pad 24 directly forms a eutectic with the electrical connection pad 11. The structure is bonded to the electrical connection pad 11, so that the thermal energy generated by the LED device 2 during operation can be directly transmitted to the circuit substrate 1 and dissipated to the atmosphere, so that the heat dissipation performance is greatly improved, and the temperature is effectively lowered. Improve the light extraction efficiency and service life of the wafer.

Referring to FIG. 2B, FIG. 11A and FIG. 11B, FIG. 2B is a flow chart (2) of a manufacturing method of the flip-chip LED package module 100 of the present invention. In step S102 and step S104, a process step S103 is further added, which is further performed by a coating process or a doping process; wherein, as shown in FIG. 11A, in the coating process, the firefly can be fired. The light material 400 is simultaneously coated on the carrier 200 and the LED chips 2 or selectively coated on the LEDs 2, and A phosphor layer or a patterned phosphor layer is formed, and as shown in FIG. 11B, in the doping process, the phosphor package 400 is incorporated into the transparent package 3 to form a phosphor colloid. Furthermore, the coating process can be carried out using a spraying device, in which the fluorescent material 400 is first loaded into the spraying device, and then the fluorescent material 400 is simultaneously sprayed on the carrier through the nozzle on the spraying device. The upper surface of the surface of the substrate 200 and the surface of the light-emitting diodes 22 or selectively applied only to the light-emitting diode wafers 2, so that the fluorescent material 400 covers only the surrounding side surface 21 and the first surface 22 of the light-emitting diode wafers 2, and then baked. The baking step causes the fluorescent material 400 to be cured into a phosphor layer or a patterned phosphor layer. It should be noted that, as shown in FIG. 11A, when the encapsulation process is performed after the coating process, the bottom surface 31 of the transparent package 3 (the surface opposite to the upper surface 202 of the carrier 200) may be coated with fluorescent light. The powder layer, especially when the phosphor powder layer is adhered to the entire outer bottom surface 31b of the transparent package 3, can reduce the interference of the light emitting diode chip 2 through the bottom surface 31, and increase the front light (as shown in FIG. 11A). The advantage of the arrow). Further, the light-emitting diode chip 2 has a side wall protective layer 25 (Fig. 3C) which can increase the proportion of the phosphor powder adhering on the circumferential side surface of the light-emitting diode wafer 2. In addition, please refer to FIG. 11B, which is a schematic diagram of a doping process according to the present invention. In the doping process, the phosphor powder 400 for adjusting the color can be directly doped into the transparent package 3, so that The transparent package 3 forms a phosphor colloid. However, the above is only one of the modes of the embodiment, and is not limited to this mode of operation.

In summary, since the present invention omits the process of wafer bonding and wire bonding, that is, there is no need for another substrate between the LED chip 2 and the circuit substrate 1, a thermal resistance can be omitted, and the heat after packaging can be eliminated. The resistance is lowered, thereby lowering the operating temperature and improving the light extraction efficiency of the LED chip 2. More specifically, the present invention directly solders the flip-chip LED package structure 300 to the circuit substrate 1 to form a flip-chip LED package module 100; wherein, due to the LED chip 2 The thermal resistance between the circuit board 1 and the circuit board 1 is only one layer of solder 500 (Fig. 10A), and the solder 500 is good again. A good thermal conductor, so the heat source of the wafer can be transmitted more effectively, achieving excellent heat dissipation. In addition, the use of flip chip packaging (sealing process and bonding process) can also eliminate the cost of gold wires and possible disconnection problems. Furthermore, the flip-chip LED package 300 removed from the carrier 200 is itself a separate component, so that a fully automated surface mount technology (SMT) can be used for flip-chip illumination. The diode package structure 300 is quickly disposed on the circuit substrate 1, so that mass production can be automated, thereby greatly reducing manufacturing and labor costs.

In addition, it is to be specifically noted herein that the directional terms mentioned in the present invention, for example, up, down, left, right, front or back, etc., are merely directions referring to the additional drawings. Therefore, the directional terminology used is for the purpose of illustration and not limitation.

Therefore, the present invention has the following features and functions:

1. The LED of the present invention has no other substrate between the substrate and the circuit substrate, which can eliminate a thermal resistance and reduce the thermal resistance after packaging, thereby reducing the operating temperature and improving the light extraction efficiency.

2. The flip-chip LED structure of the present invention is itself a separate component, so that the fully automated surface mount technology (SMT) can be used to set the flip-chip LED module. On the circuit board, it can be mass-produced through automation technology, thereby reducing the labor cost required for manufacturing.

In the flip-chip type LED module of the present invention, since the area of the metal pad of the LED of the LED is greater than or equal to the area of the electrical connection pad of the circuit substrate, the solder can be effectively prevented from being diffused during the bonding process. Contact with each other causes a short circuit or uneven soldering.

In the flip-chip type LED module of the present invention, since the electrical connection pad of the circuit substrate is higher than the solder resist layer of the circuit substrate, the bonding process of the flip-chip LED structure and the circuit substrate can be effectively avoided. At the time, the solder flows to the circuit board due to the extrusion of the solder, causing a short circuit.

V. The flip-chip LED module of the present invention, the transparent package after curing The thickness W of the flanks of the body is determined by the following equation: H1 < W < H2, H2 = R × sin θ, tan θ = H1/(L / 2), wherein H1 is the thickness of the LED chip, and the L system is The size of the light-emitting diode chip is a distance from the center point of the second surface to the first surface through the side surface and extends to a surface of the transparent package body, so that the side wing portion does not affect the light-emitting diode chip Luminous efficiency and brightness.

6. The flip-chip LED module of the present invention, the cured transparent package can be completely covered on the periphery of the LED chip and filled with gaps, so that the transparent package can firmly grasp the light. Diode wafer, not easy to degumming.

In summary, the present invention has been in conformity with the requirements of the invention patent and has been filed according to law. However, the above disclosure is only a preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, and thus the equivalent changes or modifications made in the scope of the present application are still covered by the present application.

S102 to S108‧‧‧ steps

Claims (15)

A flip-chip LED package module includes: a circuit substrate having a plurality of electrical connection pads; and a flip-chip LED package structure directly disposed on the circuit substrate, The flip-chip LED package structure includes: a light emitting diode chip having a surrounding side surface and a first surface and a second surface, the side surface and the first surface and the second surface respectively The surface is coupled to the surface, the second surface has at least one pair of wafer metal pads, the at least one pair of wafer metal pads having a gap; a transparent package covering the surrounding side surface of the LED chip, first The surface and the second surface fill the gap; and wherein the at least one pair of wafer metal pads are electrically connected to the corresponding electrical connection pads, and the bottom surface of the transparent package is separated from the circuit substrate. The flip-chip LED package module of claim 1, wherein a contact point of each of the wafer metal pads is coplanar with a bottom surface of the transparent package. The flip-chip LED package module of claim 1, wherein an area of each of the metal pads of the wafer is greater than or equal to an area of the electrical connection pad corresponding thereto. The flip-chip LED package module of claim 1, wherein the transparent package is a lens type, and a periphery of the transparent package forms a side wing portion, and a thickness W of the side wing portion is determined by the following equation: H1 < W < H2, H2 = R × sin θ, tan θ = H1/(L / 2), wherein H1 is the thickness of the light-emitting diode wafer, and L is the size of the light-emitting diode wafer, R system A θ is the angle between R and the bottom surface of the transparent package from a center point of the second surface through the side surface to the first surface and extending to a linear distance from the surface of the transparent package. The flip-chip LED package module of claim 1, further comprising a phosphor material for adjusting the color of the light, the phosphor material being located on the surface of the LED substrate or in the transparent package in. The flip-chip LED package module of claim 1, wherein the side surface further comprises a sidewall protection layer, the refractive index of the transparent package being close to or smaller than a refractive index of the sidewall protection layer. A method for manufacturing a flip-chip LED package module, comprising the steps of: disposing a plurality of LED chips on a carrier; performing a glue process to form a plurality of corresponding and covering the plurality of a transparent package of the light-emitting diode chip, the peripheral edges of the transparent package body jointly form a plurality of side wing portions, the flip-chip light-emitting diode package structures are connected to each other by the side wing portions; performing a separation process to Forming a plurality of flip-chip LED structures without the carrier; and performing a bonding process, removing at least one flip-chip LED structure from the carrier, the at least one not including the The flip-chip LED structure of the carrier is bonded to a circuit substrate. The method of manufacturing a flip-chip type LED package according to claim 7, wherein each of the light-emitting diode chips has a surrounding side surface and a first surface and a first surface in the sealing process a second surface, the side surface respectively engaging the first surface and the second surface, the second surface having at least one pair of wafer metal pads, the at least one pair of wafer metal pads having a spacing gap, the transparent packaging system The surrounding side surface, the first surface and the second surface of the LED chip are coated and filled with the gap. The method for manufacturing a flip-chip type LED package module according to claim 8, wherein in the encapsulation process, one contact point of each of the wafer metal pads, the upper surface of the carrier, and the transparent package The bottom of the three are coplanar. The method for manufacturing a flip-chip type LED package module according to claim 8, wherein when the transparent package is a lens type, the preset pitch of the wafer between each two LED chips is greater than or equal to 40% of the diagonal length of each of the light emitting diode chips, or the transparent packages are equal to the adjacent side wings, The predetermined wafer pitch between each two light-emitting diode wafers on the carrier must be greater than 0.1 mm. The method of manufacturing a flip-chip type LED package module according to claim 10, wherein in the encapsulation process, the transparent package is a lens, and the side of the transparent package is formed by a thickness W It is determined by the following equation: H1 < W < H2, H2 = R × sin θ, tan θ = H1/(L / 2), wherein H1 is the thickness of the light-emitting diode wafer, and L is the light-emitting diode wafer. Dimensions, R is a linear distance from the center point of the second surface to the first surface through the side surface and extends to the surface of the transparent package, where θ is R and the bottom surface of the transparent package Angle. The method for manufacturing a flip-chip type LED package module according to claim 8, wherein a coating process or a doping process is further performed before the encapsulation process, wherein the coating process is first sprayed through a coating process. The phosphor material is simultaneously coated on the carrier and the light emitting diode wafers or selectively coated on the light emitting diode wafers, and then passed through a heating step to form a phosphor layer on the carrier and The phosphor diodes are formed on the light-emitting diode wafers on the light-emitting diode wafers, and the doping process is performed by doping the transparent package with a phosphor material. The method of manufacturing a flip-chip LED package according to claim 8, wherein in the encapsulation process, the carrier is placed in a molding die, the molding die having a plurality of Forming holes corresponding to the light-emitting diode chips, injecting liquid transparent glue into the mold holes, and heating to form the transparent packages. The method for manufacturing a flip-chip type LED package module according to claim 8, wherein in the separating process, along the cutting path on the carrier, the cutting path between the transparent packages or a A scribe line on the cutting locating plate around the periphery of the carrier cuts the side flaps between the transparent packages. The method of manufacturing a flip-chip type LED package module according to claim 8, wherein the circuit substrate has a plurality of electrical connection pads in the bonding process. The top surface of the electrical connection pad is higher than the solder resist layer of the circuit substrate, and the area of each of the metal pads of the wafer is greater than or equal to the area of the corresponding electrical connection pad, and the corresponding metal connection is made through the metal pads of the wafer. The pads are bonded by encapsulating the solder to bond the light emitting diode wafers to the circuit substrate.