TWM568501U - Flip-chip light-emitting module - Google Patents

Abstract

The present invention provides a flip-chip light-emitting module, includes a thermal dissipation substrate, a package assembly, and a light-emitting chip. The package assembly includes a frame surrounding the thermal dissipation substrate, and a lens unit disposed on the frame. The frame includes a conductive path. The light-emitting chip is disposed on the thermal dissipation substrate, and includes a top electrode and a light-emitting surface which are at the same side. The top electrode is electrically connected with the conductive path by a conductor.

Description

Flip-chip lighting module

The invention relates to a lighting module, in particular to a flip-chip lighting module.

Human life is inseparable from lighting, and lighting devices have been gradually replaced by traditional light-emitting elements from traditional incandescent lamps, such as light-emitting diodes. Since the light-emitting diode has the advantages of small size, low energy consumption, and low driving voltage, and after forming a module together with a main circuit board including a driving circuit, it can be applied to other devices as a light source. Such modules have been widely used in such fields as house lamp indicators, backlights for displays, lighting modules for portable electronic devices, light sources for detecting devices, or lights.

Referring to FIG. 1 , a conventional light emitting module 9 includes a main circuit board 91 , an illuminating chip 92 , two wires 93 , and a package assembly 94 . The illuminating chip 92 is disposed on the main circuit board 91 and includes two conductive contacts 921 and an optical axis L respectively on opposite sides. One end of each of the wires 93 is electrically connected to the corresponding conductive contact 921, and the other end is electrically connected to the main circuit board 91. The package assembly 94 includes a bracket 941 disposed outside the light emitting chip 92 and a lens 942 disposed on the bracket 941 and opposed to the light emitting chip 92.

The main circuit board 91 is made of a polymer, and has poor heat conduction and heat dissipation capability. If there is no other heat dissipation structure, the light-emitting chip 92 attached thereto often suffers from overheating and damage due to poor heat dissipation. Moreover, the existing packaging method uses wire bonding to make electrical connection, that is, sufficient space is reserved between the light-emitting chip 92 and the bracket 941 to avoid assembling the bracket 941. Compressing to the wires 93 to cause damage or detachment, and similarly, the bracket 941 is along the optical axis The reserved space of L should not be too short, otherwise there is also a risk of pressing to the wires 93. Therefore, the design of such a package structure has the drawback that it is difficult to further reduce the volume.

The technical problem to be solved by the present invention is to provide a flip-chip type light-emitting module with good heat dissipation and reduced volume in view of the deficiencies of the prior art.

In order to solve the above technical problem, one of the technical solutions adopted by the present invention is to provide a flip-chip type light emitting module, which comprises a heat dissipating substrate, a package assembly and a light emitting chip. The package assembly includes a frame surrounding the heat dissipation substrate and a lens unit disposed on the frame. The frame body includes a conductive path. The light emitting chip is disposed on the heat dissipation substrate. The light emitting chip includes a top conductive contact on the same side and a light emitting surface. The top conductive contact is electrically connected to the conductive path through an electrical conductor.

The invention has the beneficial effects that the bonding of the light-emitting chip and the heat-dissipating substrate can effectively improve the heat dissipation effect. In addition, through the conductive path on the frame and the conductor, the light-emitting chip can be electrically connected to the outside through the package assembly (for example, the main main circuit board), and no space is required for the wire to be cut. The size of the small flip-chip illumination module helps to apply to miniaturized products. In addition, since the light-emitting wafer can be flip-chip-free without wire bonding, the electronic product using the light-emitting chip can quickly switch the light-emitting wafer without the problem of signal delay.

In order to provide a further understanding of the features and technical aspects of the present invention, reference should be made to the detailed description and drawings of the present invention. The drawings are provided for the purpose of illustration and description and are not intended to limit the invention.

1‧‧‧heated substrate

11‧‧‧ boards

12‧‧‧Heat Dissipation Channel

2‧‧‧Lighting chip

21‧‧‧Top conductive contacts

22‧‧‧Bottom conductive contacts

23‧‧‧Lighting surface

3‧‧‧ Conductive adhesive layer

4‧‧‧Package components

41‧‧‧ ‧ frame

411‧‧‧ Side wall

412‧‧‧Extension wall

42‧‧‧Electrical path

421‧‧‧ External connection

422‧‧‧Internal connection

423‧‧‧Path ontology

43‧‧‧ Filling layer

44‧‧‧ lens unit

441‧‧‧ bracket

442‧‧‧ lens

5‧‧‧Light channel

6‧‧‧Electric conductor

7‧‧‧Main circuit board

9‧‧‧Lighting module

91‧‧‧Main circuit board

92‧‧‧Lighting chip

921‧‧‧Electrical contacts

93‧‧‧Electrical path

94‧‧‧Package components

941‧‧‧ bracket

942‧‧‧ lens

L‧‧‧ optical axis

1 is a side cross-sectional view showing a conventional light emitting module.

Figure 2 is a side cross-sectional view showing the first embodiment of the present invention.

Figure 3 is a side elevational cross-sectional view showing the conductive path of the first embodiment formed on the outer surface of the frame.

Figure 4 is a side elevational cross-sectional view showing the conductive path of the first embodiment formed inside the frame.

Figure 5 is a side cross-sectional view showing another variation of the first embodiment.

Figure 6 is a side elevational cross-sectional view showing still another variation of the first embodiment.

Figure 7 is a side cross-sectional view showing the second embodiment of the present invention.

Figure 8 is a side cross-sectional view showing the third embodiment of the present invention.

Figure 9 is a side cross-sectional view showing the fourth embodiment of the present invention.

The following is a specific embodiment to illustrate the embodiment of the present invention relating to the flip-chip type light-emitting module, and those skilled in the art can understand the advantages and effects of the present invention from the contents disclosed in the specification. The present invention may be implemented or applied in various other specific embodiments, and various modifications and changes may be made without departing from the spirit and scope of the invention. In addition, the drawings of the present invention are merely illustrative and are not intended to be stated in the actual size. The following embodiments will further explain the related art content of the present invention, but the disclosure is not intended to limit the scope of protection of the present invention.

[First Embodiment]

Referring to FIG. 2, a first embodiment of the present invention provides a flip-chip type light emitting module, which is suitable for being mounted to a main circuit board 7 for cooperating with the main circuit board 7, or a flip-chip lighting module. It can be electrically connected to an external power source to be driven by the drive. The manner and field of its use are not the focus of this new type and are not described here.

The flip-chip light-emitting module includes a heat-dissipating substrate 1, a light-emitting chip 2, a conductive adhesive layer 3, a package assembly 4, and an electrical conductor 6.

The heat dissipation substrate 1 is selected from an aluminum substrate, a copper substrate, or any substrate including heat conduction or heat dissipation capability. One side of the heat dissipation substrate 1 can be electrically connected to the main circuit board 7 while the other side is electrically connected to the light-emitting chip 2.

The light-emitting chip 2 is disposed on the heat-dissipating substrate 1 and includes a top conductive contact 21, a bottom conductive contact 22, a light-emitting surface 23, and an optical axis L extending outward from the light-emitting surface 23. The top conductive contact 21 and the light emitting surface 23 are located on the same side opposite to the heat dissipation substrate 1. The bottom conductive contact 22 is electrically connected to the heat dissipation substrate 1 . Preferably, the bottom conductive contact 22 is adhered to the heat dissipation substrate 1 through the conductive adhesive layer 3 . The top conductive contact 21 is one of a positive electrode or a negative electrode, and the bottom conductive contact 22 is the other of a positive electrode or a negative electrode. The luminescent wafer 2 is selected from a light emitting diode (LED), a resonant cavity light emitting diode (RCLED), or a vertical cavity laser diode (VCSEL). In the first embodiment, a surface-emitting laser wafer is taken as an example for illustration.

The package assembly 4 defines a light tunnel 5 extending along the optical axis L and includes a frame 41, a conductive path 42, a lens unit 44, and a filling layer 44. The frame body 41 surrounds the heat dissipation substrate 1 and includes a side wall portion 411 surrounding the outer side of the heat dissipation substrate 1 and an extending wall portion 412 extending from the side wall portion 411 toward the top end conductive contact 21. The extension wall portion 412 and the top end conductive contact 21 are opposed to each other. The material of the frame body 41 may be a plastic material, a ceramic material or any insulating material. Among them, since the ceramic material includes better mechanical strength and heat resistance, the first embodiment is exemplified by using a ceramic material as an example.

The conductive path 42 is disposed on the frame 41 and includes an outer connecting end 421, an inner connecting end 422, and a path body 423 extending between the outer connecting end 421 and the inner connecting end 422. The outer connecting end 421 is located on the side wall portion 411 of the frame body 41 and is used for electrical connection with external components. The inner connecting end 422 is located at the extending wall portion 412 of the frame 41 and is electrically connected to the top conductive contact 21. The path body 423 is disposed on the frame body 41, and may be formed on the inner surface of the frame body 41 (as shown in FIG. 2), on the outer surface of the frame body 41 (as shown in FIG. 3), or embedded in the interior of the frame body 41. (Figure 4). In the present embodiment, the path body 423 is disposed on the inner surface of the frame body 41. Conductive path 42 Wires, metal domes, or the like having conductive properties can be used. The first embodiment is an example using a wire as an example.

The filling layer 43 is provided inside the frame 41 and is connected to the heat dissipation substrate 1 and the light-emitting chip 2. Therefore, the filling layer 43 is filled in the gap formed between the frame body 41 and the heat dissipation substrate 1 and the light-emitting chip 2, so that the bonding is more stable, and the structural strength of the novel flip-chip light-emitting module as a whole is improved.

The lens unit 44 is disposed on the frame 41 and includes a bracket 441 and a lens 442. The bracket 441 is made of an opaque material, which extends from the frame 41 along the optical axis L, and together with the frame 41 defines an optical channel 5 around the optical axis L. The manner in which the bracket 411 is attached to the frame body 41 is not limited, and any manner may be employed. In the first embodiment, an adhesive is used to bond the two as an example for explanation. The lens 442 is disposed on the bracket 441 and is positioned in the light tunnel 5. The lens 442 can employ a flat lens, a condensing lens, an astigmatic lens, and other types of lenses. The material of the lens 442 can be made of transparent plastic or glass. The transparent plastic may be selected from the group consisting of polymethylmethacrylate (PMMA), polycarbonate (Polycarbonate, PC), polyetherimide (PEI), Cycloolefin coplymer (COC), or Mix of etc. In the first embodiment, the lens 442 is a flat lens 442, and the material is glass as an example. However, the foregoing structures and materials are selected as examples only and are not limited thereto.

It should be noted that the number of the lenses 442 in the lens unit 44 may also be two or more, and the lens types or materials used may be the same or different, depending on the needs.

The electrical conductor 6 is disposed between the light-emitting chip 2 and the package assembly 4 and electrically connects the conductive path 42 to the top conductive contact 21 of the light-emitting chip 2. The electric conductor 6 is made of a solder ball and is interposed between the extending wall portion 412 of the frame body 41 and the top end conductive contact 21 of the light-emitting chip 2. Therefore, after the remelting, it will be located at the extending wall portion 412. The upper conductive path 42 is electrically connected to the top conductive contact 21 .

The method for fabricating the flip-chip light-emitting module can be exemplified by: first passing the conductive adhesive layer 3 The heat-dissipating substrate 1 and the light-emitting chip 2 are bonded to each other, and the solder ball is used as the conductor 6 at the top conductive contact point 21, and then the heat-dissipating substrate 1 and the light-emitting chip 2 are placed in the frame 41, and the frame 41 is pushed. The illuminating wafers 2 are close to each other such that the electric conductor 6 abuts against the inner side of the extending wall portion 412 of the frame body 41. Then, the electric conductor 6 is remelted, and the conductive path 42 and the top conductive contact 21 are electrically connected to each other, and then filled. The glue layer 43 is provided with the lens unit 44 to the frame body 41, so that the fabrication of the flip-chip type light-emitting module is completed. The foregoing manufacturing method only exemplifies a feasible process, and the manufacturer can easily adjust the process sequence or the step according to the actual needs thereof. The manufacturing method of the flip-chip light-emitting module is of course not limited to the foregoing.

Through the structural design of the package assembly 4, the luminescent wafer 2 can be assembled by using a flip chip packaging technology, and the assembly is relatively simple, and the manufacturing speed can be effectively increased and the productivity can be increased. Moreover, this method can also eliminate the disadvantage that the wire bonding needs to reserve space for the electrical connection of the wire, and effectively reduce the volume of the flip-chip light-emitting module, and is beneficial to the miniaturized product.

It is worth mentioning that the orientation of the top conductive contact 21 and the bottom conductive contact 22 of the light-emitting chip 2 is different, and the wiring in the package assembly 4 is also adjusted to match. As shown in FIG. 5, in another variation of the first embodiment, the light-emitting chip 2 further includes another top conductive contact 21, and the top conductive contacts 21 are respectively located on opposite sides of the light-emitting surface 23, and at the same time, the package assembly 4 also includes another conductive path 42. The flip-chip light-emitting module further includes another electrical conductor 6 electrically connecting the top conductive contact 21 to the conductive path 42 respectively. In this variation, the bottom conductive contact 22 acts as one of the positive or negative electrodes, and the top conductive contact 21 acts as the other of the positive or negative electrode. It is also worth mentioning that one of the top conductive contacts 21 can also be used as a conductive contact for transmitting signals. As shown in FIG. 6 , in another variation of the first embodiment, the light-emitting chip 2 does not have a bottom conductive contact 22 but includes two top conductive contacts 21 . At this time, the top conductive contacts 21 are respectively used as a positive electrode and a negative electrode. . There are two conductive paths 42 of the package assembly 4, and are electrically connected to the top conductive contacts 21, respectively. However, regardless of the conductive contact configuration of the light-emitting wafer 2, the structural design of the package assembly 4 is still The luminescent wafer 2 can be assembled by flip chip packaging technology, and has the same effect.

Through the above description, the advantages of the first embodiment can be further summarized as follows:

1. The bonding of the light-emitting chip 2 and the heat-dissipating substrate 1 can effectively improve the heat-dissipating effect. Moreover, through the conductive path 42 on the frame 41, the light-emitting chip 2 can be electrically connected to the outside through the package assembly 4, and no space is reserved for wire bonding, which can effectively reduce the volume of the flip-chip light-emitting module, and help Used in miniaturized products.

2. The design of the extending wall portion 412 in the frame 41 facilitates electrical connection between the light-emitting chip 2 and the conductive path 42 on the frame 41. When the assembly is performed, when the electric conductor 6 contacts the extending wall portion 412, that is, the electric conductor 6 is adjacent to or abuts against the conductive path 42. At this time, as long as the electrical connection is performed, for example, the solder ball is reflowed, that is, The light-emitting wafer 2 and the conductive path 42 can be electrically connected to each other.

3. The design of the frame 41 is applicable to the light-emitting chips 2 of a plurality of different conductive contact arrangements. As long as the light-emitting chip 2 is provided with the top conductive contacts 21, the flip-chip packaging technology can be used in combination with the frame body 41 for assembly. .

4. The filling layer 43 is filled in the gap formed between the frame body 41 and the heat dissipation substrate 1 and the light-emitting chip 2, so that the bonding between the frame body 41 and the light-emitting chip 2 is more stable, and the relative movement between the frame body 41 and the light-emitting chip 2 can be avoided. The electric conductor 6 falls off and is damaged. Moreover, the filling layer 43 can also prevent the conductive path 42 from coming into contact with the heat dissipation substrate 1 to cause a short circuit. Thus, the filling layer 43 can improve the overall structural stability and also prevent short circuit.

5. Since the light-emitting wafer 2 can be flip-chip-free without wiring, the electronic product using the light-emitting chip 2 can quickly switch the light-emitting wafer 2 without the problem of signal delay.

6. Since the light-emitting chip 2 of the present invention can use more than two conductive contacts, the light-emitting chip 2 can simultaneously transmit power and signals.

[Second embodiment]

Referring to FIG. 7, the second embodiment of the present invention is substantially the same as the first embodiment, and the difference is The illuminating wafer 2 includes two top conductive contacts 21 and two bottom conductive contacts 22, and correspondingly, the heat dissipation substrate 1 includes two spaced-apart plates 11. Two adjacent plates 11 together define a heat dissipation channel 12.

The number of the plate members 11 may be two, three, or four or more, and the number thereof may be adjusted according to actual needs. In the embodiment, the number of the plate members 11 is two, and the number of the heat dissipation channels 12 is one. .

As such, the second embodiment not only provides the advantages of the first embodiment, but also discloses a possible structure of another luminescent wafer 2, which includes a plurality of bottom conductive contacts 22. Corresponding to such a structure, it is only necessary to use the plurality of plate members 11 to form the heat dissipation substrate 1 correspondingly, and the heat dissipation channel 12 therein can further improve the heat dissipation effect.

It is worth mentioning that even if there is only one conductive contact 22 at the bottom, it is also possible to use a plurality of plates 11 to form the heat dissipation substrate 1, that is, to attach two or three pieces with a bottom conductive contact 22 In the above-mentioned board member 11, this method also enables the heat-dissipating substrate 1 to have a function of conducting electricity, and the heat-dissipating effect can be further improved by the heat-dissipating passage 12.

[Third embodiment]

Referring to FIG. 8, the third embodiment of the present invention is substantially the same as the first embodiment, except that the lens unit 44 does not include the bracket 441 (FIG. 2), and the lens 431 is directly disposed on the frame 41, and the frame. The body 41 simultaneously assumes the function of the bracket 441.

By removing the bracket 441 (as shown in FIG. 2), the height of the flip-chip light-emitting module can be further reduced, and the overall volume can be further reduced. Thus, the third embodiment can not only have the advantages of the first embodiment, but also further reduce the volume.

In addition, in the third embodiment, the conductive contact arrangement of the illuminating chip 2 is the same as that of the first embodiment, and the user can adjust according to actual needs without any limitation. However, for convenience of explanation, the illuminating wafer 2 of the third embodiment adopts the two top conductive contacts 21 and one bottom conductive contact 22.

[Fourth embodiment]

Referring to Fig. 9, the fourth embodiment of the present invention is substantially the same as the first embodiment, and the main difference is that the bracket 441 and the frame body 41 are integrally formed.

By integrally forming the bracket 441 and the frame body 41, it is not necessary to perform the steps of assembling the above-mentioned two in assembling the flip-chip type light-emitting module, and the strength of the structure of the package assembly 4 can be further enhanced.

Thus, the fourth embodiment not only has the advantages of the first embodiment, but further has the advantages of simplifying the process and improving the structural strength.

In addition, in the fourth embodiment, the conductive contact arrangement of the light-emitting chip 2 is the same as that of the first embodiment, and the user can adjust according to actual needs without any limitation. However, for convenience of explanation, the illuminating wafer 2 of the fourth embodiment adopts the two top conductive contacts 21 and one bottom conductive contact 22.

In summary, the structural design of the package assembly 4 enables the luminescent wafer 2 to be assembled by flip chip packaging technology, which eliminates the space reserved for wire bonding, and allows the luminescent wafer 2 to be directly attached to the heat dissipation substrate 1. Therefore, it is indeed possible to achieve the purpose of reducing the volume and improving heat dissipation of the present invention, and solving the lack of the prior art. In addition, since the light-emitting wafer 2 can be flip-chip-free without wire bonding, the electronic product using the light-emitting chip 2 can quickly switch the light-emitting wafer 2 without the problem of signal delay.

The above disclosure is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Therefore, any equivalent technical changes made by using the present specification and the contents of the drawings are included in the application of the present invention. Within the scope of the patent.

Claims (10)

A flip-chip type light emitting module comprising: a heat dissipating substrate; a package assembly comprising a frame surrounding the heat dissipating substrate and a lens unit disposed on the frame body, the frame body comprising a conductive path And a light-emitting chip disposed on the heat-dissipating substrate, the light-emitting chip includes a top conductive contact on the same side and a light-emitting surface, wherein the top conductive contact is electrically connected to the Conductive path. The flip-chip type light emitting module of claim 1, wherein the frame body comprises a side wall portion surrounding the outer side of the heat dissipation substrate and an extending wall portion extending from the side wall portion toward the top end conductive contact The conductive path includes an outer connecting end and an inner connecting end, wherein the outer connecting end is located at the side wall portion, the inner connecting end is located at the extending wall portion, and is electrically connected through the electrical conductor To the top conductive contact. The flip-chip type light emitting module of claim 2, wherein the conductive path further comprises a path body extending between the outer connecting end and the inner connecting end, wherein the path body is located in the One of the inner surface, the outer surface, and the interior of the frame. The flip-chip light-emitting module of claim 1, wherein the heat-dissipating substrate comprises a metal plate, and the light-emitting chip further comprises a bottom conductive contact electrically connected to the heat-dissipating substrate. The flip-chip light-emitting module of claim 1, wherein the light-emitting chip further includes another top conductive contact, the package assembly further includes another conductive path, and the flip-chip light-emitting module further includes Another electrical conductor, the electrical conductor electrically connecting the top conductive contacts to the conductive paths, respectively. The flip-chip type light-emitting module of claim 5, wherein the heat-dissipating substrate is composed of a plurality of spaced-apart plate members, the plate member being a metal plate, and two adjacent plates The components together define a heat dissipation channel, and the light-emitting chip further includes a plurality of bottom conductive contacts, and the bottom conductive contacts are electrically connected to the board, respectively. The flip-chip light-emitting module of claim 1, wherein the light-emitting chip further comprises an optical axis extending outward from the light-emitting surface, the lens unit further comprising a bracket disposed on the frame and A lens, the bracket and the frame define a light path around the optical axis, the lens being mounted on the bracket and positioned in the optical channel. The flip-chip type light-emitting module according to claim 7, wherein the bracket is integrally formed with the frame body. The flip-chip type light emitting module of claim 1, wherein the package assembly further comprises a filling layer filled between the frame body and the heat dissipation substrate. The flip-chip type light emitting module of claim 1, wherein the frame of the package assembly is made of a ceramic material, and the light emitting chip is selected from a light emitting diode, a resonant cavity light emitting diode, or A surface-emitting laser wafer, the conductor is a solder ball, and the conductive path is a wire.