Low-height two-step sinking photosensitive module and camera module
By designing a two-stage recessed photosensitive module in the camera module, embedding a photosensitive chip and using reinforcing metal sheets for support, and optimizing the circuit connections, the problem of difficulty in reducing the height of the camera module was solved, resulting in a lower overall module height and better imaging effect.
Patent Information
- Application Number
- CN202423017432.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-09
- Publication Date
- 2025-12-30
- Estimated Expiration
- 2034-12-09
AI Technical Summary
The height of existing camera modules is difficult to reduce further, especially when the lens TTL value is fixed. There is still redundant space in the total height of the module, which affects the appearance design of the mobile phone camera area.
A low-profile, two-tiered recessed photosensitive module is designed. By creating first-tier and second-tier recessed slots on the PCB, the photosensitive chip is embedded within the PCB. Reinforcing metal sheets support the photosensitive chip, and the arc height of the bonding wires is limited within the PCB. Combined with a multi-layer PCB structure, the circuit connections are optimized, and the overall module height is reduced.
Significantly reduces the overall height and shoulder height of the camera module, improves image quality, reduces thermal noise, increases yield, reduces moving dirt spots, and optimizes space utilization.
Smart Images
Figure CN223744811U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to camera module field, concretely relates to a two-step sunken photosensitive module of low height and camera module. BACKGROUND
[0002] At present, image acquisition function as the important selling point of mobile phone, the optical performance requirement of camera module is higher and higher, its structure size is more and more complex, the height of mobile phone camera also faces the challenge, under the premise of meeting various performance indexes, the height of module can also drop is also very important point of view. Because of the limitation of optical structure, the minimum height of lens TTL value on the market under the premise of meeting the optical performance cannot be further reduced, the conventional module design and manufacturing process cannot reduce the total height of camera module under the condition of unchanged lens TTL value.
[0003] The existing photosensitive module and camera module technical scheme refer to Figure 1 As shown, the photosensitive chip 1 is fixed on the pcb board 2 through the insulating glue, and then the binding wire 3 is used to connect the photosensitive chip 1 and the wire bonding pad 4 of the pcb board 2. The lens 5 is fixed on the connecting base 6, and the lens optical center is directed to the photosensitive chip 1 through the connecting base 6. The height T0 of the photosensitive module designed by the above existing scheme is (the thickness T3 of the photosensitive chip 1 + the thickness T4 of the pcb board 2 + the arc height and safety spacing T6 of the binding wire 3); the total height T1 of the camera module is (the lens TTL value T5 + the thickness T3 of the photosensitive chip 1 + the thickness T4 of the pcb board 2), wherein the lens TTL value is the height from the lens end face to the photosensitive chip; the total height T2 of the shoulder part of the camera module is (the thickness T3 of the pcb board 2 + the thickness T4 of the pcb board 2 + the arc height and safety spacing T6 of the binding wire 3 + the height T7 of the connecting base 6). As can be seen, under the condition of the determined lens TTL value, the photosensitive module and the camera module of the prior art still have part of the redundant space, therefore, it is necessary to design a camera module which can reduce the above part of the redundant space and provide larger TTL space for the lens, so as to solve the scheme of the surface protrusion of the mobile phone camera area. UTILITY MODEL CONTENTS
[0004] The utility model aims at further reducing the total height of the camera module without changing the lens TTL value.
[0005] Therefore, the utility model provides a two-step sunken photosensitive module of low height, which comprises a pcb board and a photosensitive chip, a first-order sunken groove is formed on the surface of the pcb board, a second-order sunken groove is formed at the bottom of the first-order sunken groove, and a step surface is formed around the second-order sunken groove, the photosensitive chip is arranged in the second-order sunken groove, the step surface is provided with a wire bonding point connected with the internal circuit of the pcb board, and the photosensitive chip is connected with the wire bonding point.
[0006] Specifically, the photosensitive chip is connected with the wire-bonding point through a bonding wire, and an arc height of the bonding wire does not exceed a surface of the PCB.
[0007] Specifically, the second-order sinking groove is a through groove.
[0008] Specifically, the PCB back surface is provided with a reinforcing metal sheet for closing a bottom opening of the second-order sinking groove, and the photosensitive chip is attached to the reinforcing metal sheet.
[0009] Specifically, the PCB is a multilayer board, the PCB multilayer board comprises a top layer, an intermediate layer and a bottom layer, the first-order sinking groove extends from a top layer surface to the intermediate layer, the second-order sinking groove extends from the intermediate layer to the bottom layer, and the step surface is located on the intermediate layer.
[0010] Specifically, the wire-bonding point is connected with an intermediate layer circuit of the PCB, and the photosensitive chip is connected with the intermediate layer circuit of the PCB through the bonding wire.
[0011] Specifically, the wire-bonding point is provided with a wire-bonding pad, one end of the bonding wire is connected with a contact of the photosensitive chip, and the other end of the bonding wire is connected with the wire-bonding pad.
[0012] Specifically, the photosensitive chip is spaced from the second-order sinking groove.
[0013] The utility model also provides a low height's camera module, including lens and connecting base, still include low height's two sinking photosensitive module of any one of above, connecting base bottom is fixed on the surface of pcb board, the shoulder part of connecting base is connected with the lens and supports the end surface of lens and faces photosensitive chip, the height of end surface of lens to photosensitive chip is TTL value of lens.
[0014] Compared with the prior art, the utility model has the following advantages and beneficial effects:
[0015] The low height's two sinking photosensitive module and the camera module provided by the utility model have the following advantages: the total height of the module is lower than that of the prior art camera module, the flatness is better controlled, the process is better controlled to control the module inclination; the internal space of the module is smaller, the moving dirty point factor is reduced, the yield is improved; the heat dissipation capacity of the photosensitive chip is stronger, the imaging thermal noise is reduced; the blur defect is reduced, and the rework maintenance rate of the later stage is significantly reduced.
[0016] The utility model will be further described in detail below with reference to the drawings. BRIEF DESCRIPTION OF DRAWINGS
[0017] Figure 1 It is a schematic diagram of the camera module structure in the prior art.
[0018] Figure 2 A cross-sectional view of a low-height, two-stage recessed photosensitive module provided by this utility model.
[0019] Figure 3 This is a schematic diagram of the structure of a low-height, two-stage recessed photosensitive module provided by this utility model. Detailed Implementation
[0020] The technical solutions of this utility model will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Although representative embodiments of this utility model have been described in detail, those skilled in the art will understand that various modifications and changes can be made to this utility model without departing from its scope. Therefore, the scope of this utility model should not be limited to the embodiments, but should be defined by the appended claims and their equivalents.
[0021] See Figure 2 , Figure 3 As shown, this embodiment of the present invention provides a low-height two-tier recessed photosensitive module, including a photosensitive chip 1 and a PCB board 2. A first-tier recessed groove is formed downwards on the surface of the PCB board 2. A second-tier recessed groove with an area not less than the surface area of the photosensitive chip 1 is formed at the center of the bottom of the first-tier recessed groove. The photosensitive chip 1 is recessed to the center of the bottom of the second-tier recessed groove and is not exposed to the surrounding PCB board 2. The bottom of the first-tier recessed groove and the second-tier recessed groove form a step. The step surface is provided with multiple bonding points connected to the circuitry inside the PCB board 2. Each bonding point is provided with a bonding pad 4. The photosensitive chip 1 is connected to the bonding pad 4 on the bonding point through a bonding wire 3. Compared with the prior art, this low-height two-tier recessed photosensitive module provided by this embodiment of the present invention, by forming a recessed groove on the PCB board and embedding the photosensitive chip inside the PCB board, reduces the height by at least the equivalent of one PCB board thickness compared to directly pasting the photosensitive chip to the PCB surface, thereby reducing the overall height of the camera module.
[0022] Furthermore, considering that wiring cannot be routed within the PCB board, one end of the bonding wire 3 is fixedly connected to the bonding point of the step formed by the first-stage and second-stage recessed grooves, and the other end is connected to the contact point on the surface of the photosensitive chip 1. With this connection method, the arc height of all bonding wires does not exceed the surface of the PCB board 2. In the implementation, the clearance distance between the second-stage recessed groove and the photosensitive chip 1 can be adjusted according to the height difference between the surface of the photosensitive chip 1 and the step surface to ensure that the arc height of the bonding wire 3 does not exceed the surface of the PCB board 2. Compared with the prior art, limiting the height of the bonding wires to within the PCB board further saves on the arc height and safety distance that need to be reserved for the bonding wires.
[0023] Optimization of the above embodiment, the second-order sink through the groove, the photosensitive chip 1 through the second-order sink groove to the pcb board 2 bottom embedded, provided with a reinforcing metal sheet 7 on the back of the pcb board 2 to close the bottom opening of the sink groove, for supporting the photosensitive chip 1, the photosensitive chip 1 is fixed on the reinforcing metal sheet 7, the reinforcing metal sheet 7 can be selected from thin reinforcing steel sheet, reinforcing copper sheet or reinforcing aluminum sheet. In the optimization embodiment, the photosensitive chip 1 and the reinforcing metal sheet 7 are directly attached to each other. Since the flatness of the reinforcing metal sheet 7 is better than that of the pcb board 2, the problem of poor imaging quality of the photosensitive chip (different clarity around) caused by the flatness of the pcb board can be reduced. In addition, considering the large amount of heat generated by the photosensitive chip during work, the heat dissipation of the reinforcing metal sheet is significantly better than that of FR4 and other pcb materials, therefore, the embodiment of the utility model can also reduce the problem of overheating of the mobile phone during normal shooting, and reduce the imaging thermal noise.
[0024] Refinement of the above embodiment, referring to Figure 2 As shown in the figure, the pcb board 2 adopts a multilayer board with no less than double layers, and a conventional 4-layer pcb board can be selected. The 4-layer pcb board has a laminated structure including a top layer, a bottom layer and two intermediate layers. The first-order sink groove bottom can be arranged in the second intermediate layer below the top layer of the pcb board 2. After removing the insulating layer between the top layer and the second intermediate layer of the pcb board 2, the circuit of the second intermediate layer of the pcb board 2 is exposed. On this basis, the second-order sink groove is arranged. The wire bonding points on the step formed by the first-order sink groove bottom and the second-order sink groove can be directly connected to the intermediate layer circuit. Further, each wire bonding point is provided with a wire bonding pad 4, and each contact of the photosensitive chip 1 is connected to the wire bonding pad 4 through a binding wire 3, and then connected to the intermediate layer circuit of the pcb board 2. By arranging the first-order sink groove bottom in the second intermediate layer of the pcb board 2, the wire bonding points can be directly arranged and connected to the second intermediate layer circuit, avoiding artificial wiring.
[0025] To show the significance of the low-height two-order sink photosensitive module provided by the embodiment of the utility model in reducing the total height of the module compared with the photosensitive module in the prior art, the embodiment of the utility model adopts the same pcb board and photosensitive chip as in the background art, that is, the thickness of the photosensitive chip 1 and the pcb board 2 in the embodiment of the utility model is Figure 1 T3 and T4 as shown in the figure. Referring to Figure 3As shown in the background art, the height of the light sensing module in the embodiment of the present application is H0=E3=(T3+T4+T6-E7), the height H0 of the light sensing module in the embodiment of the present application is at least reduced by H0-T0=(T3+T6-E7) compared with the height T0=(T3+T4+T6) of the light sensing module in the prior art. In actual situations, the limit minimum height H0-T0 of the light sensing module in the embodiment of the present application that can be reduced compared with the light sensing module in the prior art is about 0.15mm.
[0026] The embodiment of the present application also provides a low-height camera module, which comprises a lens 5 and a connecting base 6, and further comprises the low-height two-step sunken light sensing module provided by the embodiment of the present application, the bottom of the connecting base 6 is fixed to the surface of the pcb board 2, the shoulder of the connecting base 6 is connected and fixed with the lens 5 and supports the lens end face to face the light sensing chip 1, and the height of the connecting base 6 is set so that the height from the lens end face to the light sensing chip 1 is the TTL value of the lens. Figure 3As shown, since the lens TTL value is fixed, after the photosensitive chip 1 sinks into the pcb board 2, the height of the lens end face is lowered, the height of the connecting base 6 is lowered to make the lens end face close to the photosensitive chip 1, the height of the photosensitive chip 1 from the lens end face is guaranteed to be the TTL value of the lens, thereby the total height of the camera module and the shoulder height of the module can be further reduced. The total height of the camera module provided by the embodiment of the utility model is H1=E2=(lens TTL value E5+thickness of photosensitive chip E6+thickness of reinforcing metal sheet E7), the total height of the shoulder of the camera module is H2=E1=(low-height two-stage sinking photosensitive module height E3+shoulder height E4 of the connecting base 6 provided by the embodiment of the utility model). In actual situations, the total height of the low-height camera module provided by the embodiment of the utility model is lower than the total height of the camera module in the prior art, and the height difference H1-T1=(thickness of pcb board 2 T4-thickness of reinforcing metal sheet E7), wherein T4 is the thickness of a common 4-layer pcb board 0.35mm, E7 is the thickness of a thin SUS reinforcing sheet 0.01mm, and the height difference H1-T1=0.25mm, that is, the limit minimum height that can be reduced by the low-height camera module provided by the utility model compared with the prior art is about 0.25mm. Similarly, the total height of the shoulder of the low-height camera module provided by the utility model is lower than the total height of the camera module in the prior art, and the height difference is H2-T2=(thickness of photosensitive chip 1 T3+arc height and safety distance T6 of the connecting line 3-reinforcing metal sheet E7)=H0-T0, that is, the total height difference of the low-height camera module shoulder provided by the utility model compared with the total height of the camera module in the prior art is the total height difference of the photosensitive modules of the two 0.15mm. Through tests, the low-height camera module provided by the utility model can meet the reliability test, and can significantly improve the chip heat dissipation capacity, simultaneously reduce the total height of the module and the total height of the shoulder of the module compared with the prior art, further compress the total redundancy space of the camera module, reduce the internal space of the module, make the element arrangement more compact, and further reduce the mobile dirt and stain factor, and significantly improve the yield of the module.
[0027] The utility model also provides a kind of low-height two-stage sinking photosensitive module manufacturing method, comprising the following steps:
[0028] S1, the surface center of pcb board is cut down part pcb board top layer and its lower insulating layer, and intermediate layer circuit is exposed, and cut-off place forms a first sinking groove;
[0029] S2, a second sinking groove is opened in the center of the bottom of the first sinking groove, and the bottom of the first sinking groove and the second sinking groove form a step, and the surface of the step has a plurality of wire bonding points connected to the intermediate layer circuit;
[0030] S3, the reinforcing metal sheet that closes the second sinking groove bottom opening is attached to the back of the pcb board;
[0031] S4, sink the photosensitive chip along the second-order sink groove to the pcb board bottom embedded and avoid the surrounding pcb board, and adhere the photosensitive chip on the reinforcing metal sheet;
[0032] S5, setting the wire bonding pad at the wire bonding point, and the photosensitive chip is connected with the wire bonding pad through the binding wire.
[0033] The above examples are only illustrative of the present application, and do not constitute a limitation on the scope of protection of the present application, any design identical or similar to the present application belongs to the protection scope of the present application.
Claims
1. A low-height two-step sunken optical module, comprising a PCB board and an optical chip, characterized in that, The pcb board surface is provided with a first sinking groove, and a second sinking groove is provided at the bottom of the first sinking groove, and the bottom of the first sinking groove forms a stepped surface around the second sinking groove, the photosensitive chip is arranged in the second sinking groove, the stepped surface is provided with a wire bonding point connected with the internal circuit of the pcb board, and the photosensitive chip is connected with the wire bonding point.
2. The low profile two-stage sunken optical module of claim 1, wherein, The photosensitive chip and the wire bonding point are connected through a bonding wire, and the bonding wire has an arc height not exceeding the surface of the pcb board.
3. The low profile two-stage sunken optical module of claim 1, wherein, The second sinking groove is a through groove.
4. The low profile two-stage sunken optical module of claim 3, wherein, The back of the pcb board is provided with a reinforcing metal sheet closing the opening of the bottom of the second sinking groove, and the photosensitive chip is attached to the reinforcing metal sheet.
5. The low profile two-stage sunken optical module of claim 1, wherein, The pcb board is a multilayer board, which includes a top layer, an intermediate layer and a bottom layer, the first sinking groove extends from the surface of the top layer to the intermediate layer, the second sinking groove extends from the intermediate layer to the bottom layer, and the stepped surface is located on the intermediate layer.
6. The low profile two-stage sunken optical module of claim 2, wherein, The wire bonding point is connected with the intermediate layer circuit of the pcb board, and the photosensitive chip is connected with the intermediate layer circuit of the pcb board through the bonding wire.
7. The low profile two-stage sunken optical module of claim 2, wherein, The wire bonding point is provided with a wire bonding pad, one end of the bonding wire is connected with the contact of the photosensitive chip, and the other end is connected with the wire bonding pad.
8. The low profile two-stage sunken optical module of claim 1, wherein, The photosensitive chip is spaced from the second sinking groove.
9. A low-height camera module comprising a lens and a connecting base, characterized in that, Further comprising a low-height two-stage sinking photosensitive module as claimed in any one of claims 1-8, the connecting base bottom is fixed to the surface of the pcb board, the connecting base shoulder connects the lens and supports the end face of the lens facing the photosensitive chip, and the height from the end face of the lens to the photosensitive chip is the TTL value of the lens.