Novel camera module heat transfer structure, camera module and mobile terminal

Abstract

The utility model relates to a novel camera module heat transfer structure, a camera module and a mobile terminal. The novel camera module heat transfer structure comprises a copper sheet arranged on the back surface of an RFPC rigid-flex board; the heat dissipation copper piece is used for carrying out heat dissipation on the photosensitive chip; at least one first through hole is formed in the position, corresponding to the photosensitive chip, of the RFPC rigid-flex board; a first connecting part extending downwards is arranged at the position, corresponding to the first through hole, of the heat dissipation copper piece, and / or a second connecting part extending upwards is arranged at the position, corresponding to the first through hole, of the copper sheet; and the heat dissipation copper piece is in contact with the copper sheet through the first connecting part and / or the second connecting part. According to the utility model, heat at the bottom of the photosensitive chip can be quickly conducted out.

Description

Technical Field

[0001] The utility model relates to the technical field of heat dissipation of camera modules, and in particular to a novel camera module heat transfer structure, a camera module and a mobile terminal. Background Art

[0002] With the rapid development of science and technology, the market demand for camera modules with higher pixels and stricter performance requirements, the power consumption of photosensitive chips used in camera modules is also increasing, so heat dissipation has become an issue that must be paid attention to. At present, all manufacturers are trying to optimize the heat dissipation of camera modules to solve all camera problems caused by excessive temperature, such as reduced resolution, increased noise, and image distortion.

[0003] The heat dissipation structure of the existing camera module generally adopts the following structure:

[0004] (1) Currently, the heat dissipation design of most camera modules starts from the bracket, such as adding a heat dissipation S shape on the bracket. The heat of the photosensitive chip needs to be transferred to the bracket through the air. Due to the low thermal conductivity of air, the heat dissipation effect is not good.

[0005] (2) Another design uses the gold wire on the front of the photosensitive chip to transfer heat to the RFPC hard-flex board, and then dissipates heat through the exposed copper on the back of the RFPC hard-flex board. Since the heating surface of the photosensitive chip is at the bottom, the effect of heat conduction from the front of the photosensitive chip is not ideal.

[0006] Therefore, it is necessary to develop a new camera module heat transfer structure, camera module and mobile terminal. Summary of the invention

[0007] The purpose of the utility model is to provide a novel camera module heat transfer structure, a camera module and a mobile terminal, which can quickly export the heat at the bottom of a photosensitive chip.

[0008] In the first aspect, the novel camera module heat transfer structure described in the utility model includes a copper sheet arranged on the back of the RFPC soft-hard combination board; and also includes a heat dissipation copper piece for dissipating heat from the photosensitive chip;

[0009] The RFPC hard-flex board is provided with at least one first through hole at a position corresponding to the photosensitive chip;

[0010] A first connecting portion extending downward is provided on the heat dissipation copper piece at a position corresponding to the first through hole and / or a second connecting portion extending upward is provided on the copper sheet at a position corresponding to the first through hole;

[0011] The heat dissipation copper piece is in contact with the copper sheet through the first connection portion and / or the second connection portion.

[0012] Optionally, when the heat dissipating copper piece is provided with a first connecting portion, and the copper sheet is provided with a second connecting portion;

[0013] A second through hole is provided on the first connecting portion;

[0014] The second connection part is located in the second through hole, and the top surface of the second connection part is in contact with the photosensitive chip. Since the second connection part is in direct contact with the bottom of the photosensitive chip, the heat at the bottom of the photosensitive chip can be well transferred to the copper sheet, and then the heat is quickly transferred to the surface of the camera module through the high thermal conductivity and large area of ​​the copper sheet, thereby achieving a good heat dissipation effect.

[0015] Optionally, when the heat dissipating copper piece is provided with a first connecting portion, and the copper sheet is provided with a second connecting portion;

[0016] The second connection part is provided with a third through hole, and the first connection part is located in the third through hole. By increasing the contact area between the heat dissipation copper piece and the copper sheet, a better heat dissipation effect is achieved.

[0017] Optionally, one of the first through holes is provided on the RFPC rigid-flexible board, and the first through hole is a square hole with a side length of 2 mm-3 mm.

[0018] Optionally, the copper sheet and the heat dissipating copper piece are both made of phosphor copper or brass. The phosphor copper sheet has a high thermal conductivity of about 380W / (m·k), and the brass sheet has a high thermal conductivity of about 109W / (m·k), which can quickly remove the heat from the bottom of the photosensitive chip.

[0019] Optionally, the periphery of the photosensitive chip is fixedly connected to the heat dissipation copper piece and the RFPC hard-soft board through DA glue, which can ensure reliable connection between the photosensitive chip, the heat dissipation copper piece and the RFPC hard-soft board.

[0020] In a second aspect, a camera module described in the present invention adopts the novel camera module heat transfer structure described in the present invention.

[0021] In a third aspect, a mobile terminal described in the present utility model adopts the camera module described in the present utility model.

[0022] (1) The utility model adds a heat-dissipating copper piece, which is in direct contact with the bottom surface of the photosensitive chip. At the same time, a copper sheet is added to the back of the RFPC soft-hard combination board, and the heat-dissipating copper piece can be connected to the copper sheet. Since the thermal conductivity of the heat-dissipating copper piece and the copper sheet is very high, and the contact area between the heat-dissipating copper piece and the photosensitive chip is large, the heat-dissipating copper piece can quickly conduct the heat generated by the photosensitive chip when it is working to the copper sheet, and finally transfer it to the outside of the camera module through the copper sheet.

[0023] (2) The setting of copper sheet can also play a good reinforcing role.

[0024] (3) The copper sheet and the heat dissipation copper parts are both made of phosphor copper sheet or brass sheet. Both phosphor copper sheet and brass sheet have high thermal conductivity, and the copper sheet has a large heat dissipation area, so it can further speed up the heat dissipation from the bottom of the photosensitive chip, and the temperature can be reduced by 5℃~8℃.

[0025] In summary, the utility model greatly improves the heat dissipation efficiency of the camera module while ensuring that the external dimensions of the camera module remain unchanged, which is beneficial to the stability of the long-term working performance of the camera module. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the structure of Example 1 in the embodiments of the present application;

[0027] Figure 2 This is a schematic diagram of the structure of Example 2 in the embodiments of the present application;

[0028] Figure 3 This is a schematic diagram of the structure of Example 3 in the embodiments of the present application;

[0029] Figure 4 This is a schematic diagram of the structure of Example 4 in the embodiments of the present application;

[0030] Figure 5 It is a schematic diagram of the structure of Example 1 or Example 3 in the embodiments of the present application;

[0031] Figure 6 It is a structural schematic diagram of the prior art;

[0032] Figure 7 It is a structural schematic diagram of the photosensitive chip;

[0033] Explanation of the reference numerals in the accompanying drawings: 1. bracket, 2. capacitor, 3. LHA glue, 4. RFPC hard-soft board, 4a. first through hole, 5. copper sheet, 5a. second connecting part 5a, 6. DA glue, 7. photosensitive chip, 8. connector, 9. gold wire, 10. filter, 11. steel sheet, 12. microlens, 13. color filter, 14. photosensitive diode, 15. semiconductor partition wall, 16. metal wiring, 17. lens, 18. motor, 19. heat dissipation copper part, 19a. first connecting part. DETAILED DESCRIPTION

[0034] The following will refer to the accompanying drawings and preferred embodiments to illustrate the implementation of the technical solution of the utility model. Those skilled in the art can easily understand other advantages and effects of the utility model from the contents disclosed in this specification. The utility model can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the utility model. It should be understood that the preferred embodiments are only for illustrating the utility model, not for limiting the scope of protection of the utility model.

[0035] like Figure 6 As shown, the existing camera module includes a bracket 1, a capacitor 2, an RFPC hard-soft board 4, a photosensitive chip 7, a filter 10, a steel sheet 11, a resistor (not shown in the figure), a lens 17 and a motor 18. Among them: the RFPC hard-soft board 4 mainly bears the photosensitive chip 7, the bracket 1, the resistor and the capacitor 2. The steel sheet 11 mainly increases the reinforcement of the RFPC hard-soft board 4 and improves the strength. The bracket 1 mainly protects the capacitor 2 and the photosensitive chip 7 and is used to support the filter 10. The filter 10 mainly filters out stray light and transmits useful visible light to the photosensitive chip 7. The lens 17 is used to collect light within the respective shooting ranges so that the light is projected onto the photosensitive chip 7. The motor 18 is used to control the movement of the lens 17. The connector 8 is used to communicate with the mainboard of the mobile terminal. The photosensitive chip 7 is the electronic component with the highest power consumption and the highest heat generation in the camera module, so the heat dissipation of the photosensitive chip 7 is particularly important.

[0036] like Figure 7 As shown, the stacking structure of the photosensitive chip 7 is as follows: the top layer is the microlens 12, which is mainly used to receive the light transmitted by the lens 17 and the filter 10, and converge it on the photosensitive chip 7. The second layer is the color filter 13, which is mainly used to filter out the three primary colors of red, green and blue for each pixel. The third layer is the photosensitive diode 14, which mainly converts the received red, green and blue light signals into electrical signals. There are semiconductor partitions 15 between the photosensitive diodes 14, which are used to isolate the red, green and blue light signals to avoid crosstalk between different light. The bottom layer is the metal wiring 16. This layer is designed with electronic components such as analog-to-digital conversion circuits, signal amplification circuits, noise reduction circuits, and Layout (referring to layout) wiring. The heat generated by the photosensitive chip 7 is mainly generated in this layer.

[0037] In the existing camera module, although the RFPC hard-soft board 4 is provided with a thermal through hole, and the thermal conductivity of the thermal through hole is relatively high, the aperture of the thermal through hole is generally only about 0.15 mm, and the reverse side of most of the thermal through holes will be covered with a layer of 25um ink to avoid short circuit, which will affect the thermal conductivity. In addition, the thermal conductivity of the middle FCCL layer (FCCL layer refers to the soft board substrate), PP layer (PP layer refers to the semi-cured sheet), and ink layer of the RFPC hard-soft board 4 are all less than 1W / (m•k), so it is not enough to transfer the heat generated by the photosensitive chip 7 when it is working to the outside in time. In addition, the thermal conductivity of the bracket 1 is generally less than 2W / (m•k), the thermal conductivity is very low, and it is not conducive to rapid heat transfer. The main material of the filter 10 is glass, and the thermal conductivity of glass is only 1W / (m•k), the thermal conductivity is also very low, and it is not conducive to rapid heat transfer.

[0038] like Figure 3 As shown, in the existing camera module, the photosensitive chip 7 is generally bonded to the RFPC hard-soft board 4 by DA glue 6, and the photosensitive chip 7 is electrically connected to the RFPC hard-soft board 4 by gold wire 9. The thermal conductivity of DA glue 6 (Die-Attach glue) is generally less than 1W / (m•k). The bracket 1 is fixed to the RFPC hard-soft board 4 by LHA glue 3. The thermal conductivity of LHA glue 3 is generally less than 1W / (m•k), and the thermal conductivity is also very low, which is also not conducive to the rapid transfer of heat. The heat generated by the bottom layer of the photosensitive chip 7 is transferred to the outside of the camera module through DA glue 6, RFPC hard-soft board 4, and steel sheet 11, but because the thermal conductivity of DA glue 6 and RFPC hard-soft board 4 is very low, the thermal conductivity of steel sheet 11 is only 16.3W / m•k. When the photosensitive chip 7 works at high speed and for a long time, it is difficult to quickly transfer the heat to the outside of the camera module, which leads to the accumulation of heat in the camera module, which is not conducive to the normal operation of the camera module.

[0039] like Figures 1 to 3As shown, in order to solve the above problems, a new camera module heat transfer structure is provided in the embodiment of the present application. By adding a heat dissipation copper piece 19, the photosensitive chip 7 is set on the heat dissipation copper piece 19. At the same time, at least one first through hole 4a is provided on the RFPC soft-hard combination board 4 at a position corresponding to the photosensitive chip 7. The heat dissipation copper piece 19 is provided with a first connecting portion 19a extending downward at a position corresponding to the first through hole 4a and / or the copper sheet 5 is provided with a second connecting portion 5a extending upward at a position corresponding to the first through hole 4a. The heat dissipation copper piece 19 contacts the heat dissipation copper piece 19 through the first connecting portion 19a and / or the second connecting portion 5a. Because the thermal conductivity of the heat dissipation copper piece 19 is very high, and the contact area between the heat dissipation copper piece 19 and the bottom surface of the photosensitive chip 7 is large enough, the heat dissipation copper piece 19 can quickly conduct the heat generated by the photosensitive chip 7 when it is working to the copper sheet 5, and finally transfer it to the outside of the camera module through the copper sheet 5. In this embodiment, " / " means "or".

[0040] like Figure 1 As shown, in a possible embodiment, a first connection portion 19a is provided on the heat dissipation copper piece 19; a second connection portion 5a is provided on the copper sheet 5; preferably, a second through hole is opened on the first connection portion 19a; the second connection portion 5a is located in the second through hole, and the top surface of the second connection portion 5a is in contact with the photosensitive chip 7. During installation, the second connection portion 5a of the copper sheet 5 is inserted into the second through hole of the first connection portion 19a. This method has the advantages of good positioning effect and convenient installation. At the same time, the photosensitive chip 7 can directly contact the heat dissipation copper piece 19 and the copper sheet 5, and the contact area is large enough, so the heat generated by the photosensitive chip 7 during operation can be quickly transferred to the outside of the camera module.

[0041] like Figure 4 As shown, in a possible embodiment, when the heat dissipation copper piece 19 is provided with a first connection part 19a; the copper sheet 5 is provided with a second connection part 5a; the second connection part 5a may also be provided with a third through hole; and the first connection part 19a is located in the third through hole. During installation, the second connection part 5a is inserted into the third through hole of the first connection part 19a, which has the advantages of good positioning effect and convenient installation. Since the contact area between the photosensitive chip 7 and the heat dissipation copper piece 19 is large enough, and the contact area between the heat dissipation copper piece 19 and the copper sheet 5 is also large enough, the heat generated by the photosensitive chip 7 during operation can be quickly transferred to the outside of the camera module.

[0042] like Figure 2 As shown, only the first connecting portion 19a extending downward is provided on the heat dissipating copper member 19, and the bottom surface of the first connecting portion 19a is directly in contact with the copper sheet 5. This connection method also has a good heat conduction effect.

[0043] like Figure 3As shown, only the second connection portion 5a extending upward is provided on the copper sheet 5, and the top surface of the first connection portion 19a is directly in contact with the copper sheet 5. This connection method also has a good heat conduction effect.

[0044] like Figure 5 As shown, in a possible embodiment, the number of the first through hole 4a is preferably one, and the side length of the first through hole 4a is a square hole of 2mm-3mm. Of course, more than one first through hole 4a can be provided, and the shape of the first through hole 4a can also be changed at will.

[0045] In a possible embodiment, the copper sheet 5 and the heat dissipation copper part 19 are both made of phosphor copper sheet. The copper sheet 5 can increase the reinforcement effect of the RFPC soft-hard combination board 4. At the same time, the thermal conductivity of the phosphor copper sheet is 380W / m·k, and its thermal conductivity is very high. The heat generated by the photosensitive chip 7 during operation is quickly exported to the phosphor copper sheet, and then the heat is transferred to the surface of the camera module through the high thermal conductivity and large area of ​​the phosphor copper sheet, thereby achieving a good heat dissipation effect.

[0046] In a possible embodiment, the copper sheet 5 and the heat dissipating copper part 19 are both made of brass sheets. The thermal conductivity of the brass sheet is relatively high (the thermal conductivity coefficient is about 109 W / (m·k)). At the same time, the heat dissipation area of ​​the copper sheet 5 is relatively large, and the heat at the bottom of the photosensitive chip can be quickly discharged.

[0047] In the embodiment of the present application, the photosensitive chip 7 is carried on the heat dissipation copper part 19. At the same time, the periphery of the photosensitive chip 7 is bonded to the RFPC hard-soft combination board 4 and the heat dissipation copper part 19 by using DA glue 6. The DA glue 6 can well bond the photosensitive chip 7 to the RFPC hard-soft combination board 4 and the heat dissipation copper part 19, thereby ensuring the reliability of the fixation of the photosensitive chip 7.

[0048] In an embodiment of the present application, a camera module adopts the novel camera module heat transfer structure as described in the embodiment of the present application.

[0049] In an embodiment of the present application, a mobile terminal adopts the camera module as described in the embodiment of the present application.

[0050] The above-mentioned embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited by the above-mentioned embodiments. Any other changes, modifications, substitutions, combinations and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement modes and shall be included in the protection scope of the present invention.

Claims

1. A novel camera module heat transfer structure, comprising a copper sheet (5) arranged on the back of an RFPC hard-flex board (4); characterized in that: It also includes a heat dissipation copper piece (19) for dissipating heat from the photosensitive chip (7); At least one first through hole (4a) is provided on the RFPC hard-flex board (4) at a position corresponding to the photosensitive chip (7); The heat dissipation copper piece (19) is provided with a first connection portion (19a) extending downward at a position corresponding to the first through hole (4a), and / or the copper sheet (5) is provided with a second connection portion (5a) extending upward at a position corresponding to the first through hole (4a), The heat dissipating copper piece (19) is in contact with the copper sheet (5) via the first connecting portion (19a) and / or the second connecting portion (5a).

2. The novel camera module heat transfer structure according to claim 1, characterized in that: When the heat dissipation copper piece (19) is provided with a first connection portion (19a); and the copper sheet (5) is provided with a second connection portion (5a); The first connecting portion (19a) is provided with a second through hole; The second connecting portion (5a) is located in the second through hole, and the top surface of the second connecting portion (5a) is in contact with the photosensitive chip (7).

3. The novel camera module heat transfer structure according to claim 1, characterized in that: When the heat dissipation copper piece (19) is provided with a first connection portion (19a); and the copper sheet (5) is provided with a second connection portion (5a); The second connecting portion (5a) is provided with a third through hole; the first connecting portion (19a) is located in the third through hole.

4. The novel camera module heat transfer structure according to any one of claims 1 to 3, characterized in that: The RFPC hard-flex board (4) is provided with a first through hole (4a), and the first through hole (4a) is a square hole with a side length of 2 mm to 3 mm.

5. The novel camera module heat transfer structure according to claim 1 is characterized in that: The copper sheet (5) and the heat dissipating copper piece (19) are both made of phosphor copper or brass.

6. The novel camera module heat transfer structure according to claim 1, characterized in that: The periphery of the photosensitive chip (7) is fixedly connected to the heat dissipation copper piece (19) and the RFPC hard-flex board (4) via DA glue (6).

7. A camera module, characterized in that: A new camera module heat transfer structure as described in any one of claims 1 to 6 is adopted.

8. A mobile terminal, characterized in that: Use the camera module as described in claim 7.

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