Infrared receiving module and manufacturing method thereof

Abstract

The embodiment of the present invention provides an infrared receiving module and a manufacturing method thereof. The infrared receiving module includes a base, a signal processing chip, a packaging layer and N light receiving unit groups. The light receiving unit group includes at least one light receiving unit, and the light receiving unit is arranged on the front of the base; the packaging layer is arranged on the front of the base, and is used to package the circuit and the light receiving unit on the front of the base; the back of the base is provided with an inwardly concave cavity, and the signal processing chip is installed in the cavity; the back of the base is also provided with a pad group, and the pad group includes a plurality of pads; the light receiving unit, the signal processing chip, and the pads are connected. The technical problem that the existing infrared receiving module is not perfect is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of infrared reception, and in particular to an infrared receiving module and a manufacturing method thereof. Background Art

[0002] In existing infrared receiver modules (IRM), the light receiving unit and the signal processing chip are usually arranged on the same surface of the base. The light receiving unit is such as a photodiode (PD) and the signal processing chip is such as a Pre-AMP. In order to improve the anti-interference ability of the signal processing chip, it is also necessary to add a metal inner shielding shell or a metal outer shielding shell on the surface of the signal processing chip. This solution has a series of problems, such as: large size, poor anti-interference ability, affecting the receiving distance and angle, and poor light receiving effect. Summary of the invention

[0003] An infrared receiving module and a manufacturing method thereof provided in an embodiment of the present invention solve the technical problem that the existing infrared receiving modules are not perfect.

[0004] To solve the above technical problems, an embodiment of the present invention provides an infrared receiving module, including a base, a signal processing chip, a packaging layer and N light receiving unit groups, N is greater than or equal to 1, wherein:

[0005] The light receiving unit group includes at least one light receiving unit, and the light receiving unit is arranged on the front side of the base;

[0006] The encapsulation layer is arranged on the front side of the base, and is used to encapsulate the circuit on the front side of the base and the light receiving unit;

[0007] An inwardly concave cavity is provided on the back of the base, and the signal processing chip is installed in the cavity;

[0008] A pad group is also provided on the back of the base, and the pad group includes a plurality of pads;

[0009] The light receiving unit, the signal processing chip, and the pad are connected.

[0010] In order to solve the above technical problems, an embodiment of the present invention provides a method for manufacturing an infrared receiving module, which is used to manufacture the above infrared receiving module. The method for manufacturing the infrared receiving module includes:

[0011] S101, manufacturing a conjoined base body, wherein the conjoined base body comprises M continuous bases, and a pad group and an inwardly concave cavity are arranged on the back of each base, wherein the pad group comprises a plurality of pads, and M is greater than or equal to 1;

[0012] S102, setting N light receiving unit groups on the front of each base, wherein the light receiving unit group includes at least one light receiving unit; setting a signal processing chip in the cavity of each base; connecting the light receiving unit, the signal processing chip, and the pad on each base;

[0013] S103, disposing a packaging layer on the front side of the integrated base body to obtain an integrated module;

[0014] S104, cutting the connected module to obtain M infrared receiving modules.

[0015] Beneficial Effects

[0016] In the infrared receiving module and the manufacturing method thereof provided by the embodiment of the present invention, the light receiving unit is arranged on the front side of the base, the back side of the base is arranged with an inwardly concave cavity, and the signal processing chip is installed in the cavity. Since the signal processing chip and the light receiving unit are arranged on different sides of the base, the signal processing chip and the light receiving unit do not affect each other, thus avoiding the signal processing chip affecting the light receiving effect of the light receiving unit. With the optical design of the packaging layer, the infrared receiving module can realize infrared reception from 0 degrees to 180 degrees; the signal processing chip arranged in the cavity on the back side of the base can also avoid being affected by external light and electromagnetics, so that the infrared receiving module has better anti-interference ability; at the same time, the packaging volume is also reduced.

[0017] Furthermore, a protective layer is provided inside the cavity and / or on the back surface of the base. The main function of the protective layer is to block the mouth of the cavity to prevent the signal processing chip from being affected by external forces or the external environment. In some embodiments, the protective layer can further serve to fix the signal processing chip. In some embodiments, the protective layer can further serve as an anti-interference shielding shell to further prevent the signal processing chip from being affected by external light and electromagnetics.

[0018] Furthermore, a circuit connected to the light receiving unit is arranged on the front of the base, and the circuit and the signal processing chip, and the signal processing chip and the pad are connected through internal vias or surface grooves of the base, for example, by routing or copper deposition in the internal vias or surface grooves of the base to make electrical connections, making the overall structure more compact, reducing the volume, and improving safety.

[0019] Other features and corresponding beneficial effects of the present invention are described in the latter part of the specification, and it should be understood that at least part of the beneficial effects become obvious from the description in the specification of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the structure of an infrared receiving module provided in Embodiment 1 of the present invention;

[0021] Figure 2 A schematic flow chart of a method for manufacturing an infrared receiving module provided in Embodiment 2 of the present invention;

[0022] Figure 3 A schematic diagram of the structure of an infrared receiving module provided in Embodiment 3 of the present invention;

[0023] Figure 4 A schematic diagram of the structure of the first circuit layer in the infrared receiving module provided in the third embodiment of the present invention;

[0024] Figure 5 A schematic diagram of the structure of the second circuit layer in the infrared receiving module provided in the third embodiment of the present invention;

[0025] Figure 6 This is a schematic diagram of the structure of the third circuit layer in the infrared receiving module provided in the third embodiment of the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the following is a further detailed description of the embodiments of the present invention through specific implementation methods combined with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0027] Embodiment 1:

[0028] The following is a further detailed description of the specific implementation of the present invention in conjunction with the accompanying drawings and implementation examples. This embodiment provides an infrared receiving module, see Figure 1 As shown, the infrared receiving module includes: a base 11, a signal processing chip 12, a packaging layer and N light receiving unit groups, N is greater than or equal to 1, wherein the light receiving unit group includes at least one light receiving unit 14, and the light receiving unit 14 is arranged on the front of the base 11; the packaging layer is arranged on the front of the base 11, and is used to encapsulate the circuit and the light receiving unit 14 on the front of the base 11; the back of the base 11 is provided with an inwardly concave cavity 111, and the signal processing chip 12 is installed in the cavity 111; the back of the base 11 is also provided with a pad group, and the pad group includes a plurality of pads 112; the light receiving unit 14, the signal processing chip 12, and the pads 112 are connected. The light receiving unit 14 is used to receive infrared rays and convert the received infrared rays into electrical signals; the light receiving unit can be a photodiode PD. The signal processing chip 12 is used to decode and process the electrical signals transmitted by the light receiving unit 14.

[0029] Figure 1Only two light receiving unit groups are shown, and each light receiving unit group includes a light receiving unit 14. In other embodiments, the infrared receiving module may include one or more light receiving unit groups, each light receiving unit group may include at least one light receiving unit 14, the number of light receiving units 14 in each light receiving unit group may be the same or different, and the arrangement order of each light receiving unit group and each light receiving unit in each light receiving unit group may be determined according to user needs.

[0030] The encapsulation layer can be prefabricated in advance and then installed on the front of the base 11; or the encapsulation layer can be molded by injection molding on the front of the base 11. Optionally, the encapsulation layer is opaque. Optionally, the encapsulation layer can filter or isolate visible light, and can be made by doping a transparent colloid with a pigment that filters or isolates visible light wavelengths. Optionally, in order to make the light receiving unit 14 have a better light receiving effect, the encapsulation layer area above the light receiving unit 14 can be made in the form of a convex lens, so that the infrared receiving module can achieve infrared reception from 0 degrees to 180 degrees. In some embodiments, the encapsulation layer may include a first sub-encapsulation layer, and N second sub-encapsulation layers corresponding to the light receiving unit group one by one, the second sub-encapsulation layer is a hemispherical protrusion, which is arranged directly above the corresponding light receiving unit group, and the first sub-encapsulation layer is arranged in other areas on the front of the base 11; optionally, the first sub-encapsulation layer and the N second sub-encapsulation layers can be an integral structure. Figure 1 The packaging layer shown includes a first sub-packaging layer 131 and two second sub-packaging layers 132 corresponding one-to-one to the light receiving unit groups. Each second sub-packaging layer 132 is a hemispherical protrusion and is arranged one-to-one directly above the two light receiving unit groups. The first sub-packaging layer 131 is arranged in other areas of the front side of the base 11, and the first sub-packaging layer 131 and the two second sub-packaging layers 132 are an integrated structure.

[0031] Optionally, the infrared receiving module may further include a protective layer 15, which is disposed in the cavity 111 and / or on the back surface of the base 11. The protective layer 15 may be disposed in the cavity 111 and flush with the back surface of the base 11; or the protective layer 15 may be disposed only on the back surface of the base 11, covering the mouth of the cavity 111; or the protective layer 15 may be disposed in the cavity 111, lower than the back surface of the base 11; the protective layer 15 may be disposed by filling the cavity 111 with colloid, or may be prefabricated in advance and then installed in the cavity 111 and / or on the back surface of the base 11. Figure 1The protective layer 15 shown is disposed in the cavity 111 and is flush with the back surface of the base 11. The main function of the protective layer 15 is to block the mouth of the cavity 111 to prevent the signal processing chip 12 from being affected by external forces or the external environment; in some embodiments, the protective layer 15 can further serve to fix the signal processing chip 12; in some embodiments, the protective layer 15 can further serve as an anti-interference shielding shell to further prevent the signal processing chip 12 from being affected by external light and electromagnetics.

[0032] The pad group provided on the back of the base 11 is used to realize the connection between the infrared receiving module and the external circuit or external power supply. The pad 112 can be directly pasted or welded on a carrier, such as a PCB board, to connect with the circuit on the PCB board; the pad 112 can also be pasted or welded with a lead pin, the height is controlled by the lead pin, and the lead pin is connected to other circuits or power supplies.

[0033] In some embodiments, the pad group may include three pads 112, namely a ground pad GND, a power input pad VCC and a data output pad OUT, wherein the ground pad GND is connected to the ground terminal GND of the signal processing chip 12, the power input pad VCC is connected to the power input terminal VCC of the signal processing chip 12, and the data output pad OUT is connected to the signal output terminal OUT of the signal processing chip 12; the signal processing chip 12 also has a signal input terminal IN corresponding to the light receiving unit group or the light receiving unit 14 one by one, and the signal input terminal IN is connected to the positive electrode of the corresponding light receiving unit 14; the negative electrode of the light receiving unit 14 is connected to the ground terminal GND of the signal processing chip 12. In some embodiments, four pads 112 may be set on the back side of the base 11. In addition to the above three pads 112, the fourth pad 112 is also a ground pad GND, which is connected to the ground terminal GND of the signal processing chip 12. Figure 1 As shown, four pads 112 are shown, and the four pads 112 are arranged on the long sides of the square base 11.

[0034] In some embodiments, a circuit connected to the light receiving unit 14 may be provided on the front of the base 11, and the circuit and the signal processing chip 12, and the signal processing chip 12 and the pad 112 may be connected through internal vias or surface grooves of the base 11. Specifically, electrical connection may be made by routing or copper deposition in the internal through holes or surface grooves of the base 11. Electrical connection is achieved through internal vias or surface grooves of the base 11, making the overall structure more compact, reducing the volume, and improving safety.

[0035] In some embodiments, the cavity 111 may be disposed in a middle region of the back side of the base 11 ; the pad 112 may be disposed in an edge region of the back side of the base 11 , surrounding the cavity 111 .

[0036] The structure of the base 11 is not limited. As an embodiment, the base 11 may include a first circuit layer, a first insulating layer, a second circuit layer, a second insulating layer and a third circuit layer arranged from top to bottom, wherein:

[0037] The first circuit layer is connected to the light receiving unit 14;

[0038] The second circuit layer is connected to the signal processing chip 12;

[0039] The third circuit layer includes the above-mentioned pad group;

[0040] The first circuit layer and the second circuit layer are connected through internal via holes or surface grooves of the first insulating layer, and the second circuit layer and the third circuit layer are connected through internal via holes or surface grooves of the second insulating layer.

[0041] The base 11 of the above structure realizes the connection of the first circuit layer, the second circuit layer, and the third circuit layer inside or on the surface of the base through internal vias or surface grooves, thereby realizing the connection between the light receiving unit 14, the signal processing chip 12, and the pad 112 inside or on the surface groove of the base 11. The connection between the light receiving unit 14, the signal processing chip 12, and the pad 112 is simple, stable, and compact; the compactness of the overall structure of the infrared receiving module is realized; and the three circuit layers form their own shielding cover around the signal processing chip 12, reducing the signal interference of the environment on the signal processing chip 12.

[0042] Optionally, the second circuit layer can be connected to the signal processing chip 12 through metal connecting wires, which include but are not limited to gold wires. For example, the second circuit layer is connected to the ground terminal GND, the power input terminal VCC, the signal output terminal OUT, and the signal input terminal IN of the signal processing chip 12 through gold wires.

[0043] Optionally, the signal processing chip 12 is installed in the cavity 111 and is arranged in the same plane as the second circuit layer; or the signal processing chip 12 is installed in the cavity 111 and is arranged below the second circuit layer, adjacent to the second circuit layer. This arrangement, firstly, facilitates the connection between the signal processing chip 12 and the second circuit layer and ensures the stability of the connection between the two; secondly, it makes the overall circuit connection compact and simpler; thirdly, the second circuit layer forms its own shielding cover around the signal processing chip 12 to reduce the environmental interference with the signal of the signal processing chip 12.

[0044] Optionally, the base 11 may be made of one or more plates. In the following, the base 11 includes two plates as an example. The base 11 may include a first plate and a second plate arranged from top to bottom.

[0045] In one embodiment, the first plate includes a first circuit layer, a first insulating layer, and a second circuit layer, and the second plate includes a second insulating layer and a third circuit layer; in this embodiment, the first plate may be a double-sided PCB board or a BT board, and the second plate may be a single-sided PCB board or a BT board, or the second plate may be a double-sided PCB board or a BT board with one circuit layer removed;

[0046] In another embodiment, the first plate includes a first circuit layer and a first insulating layer, and the second plate includes a second circuit layer, a second insulating layer and a third circuit layer; in this embodiment, the first plate can be a single-sided PCB board or a BT board, or the first plate can be a double-sided PCB board or a BT board with one side of the circuit layer removed; the second plate can be a double-sided PCB board or a BT board.

[0047] In the infrared receiving module provided in this embodiment, the light receiving unit 14 is arranged on the front side of the base 11, the back side of the base 11 is arranged with an inwardly concave cavity 111, and the signal processing chip 12 is installed in the cavity 111. Since the signal processing chip 12 and the light receiving unit 14 are arranged on different sides of the base 11, the signal processing chip 12 and the light receiving unit 14 do not affect each other, thus avoiding the signal processing chip 12 affecting the light receiving effect of the light receiving unit 14, and with the optical design of the packaging layer, the infrared receiving module can achieve infrared reception from 0 degrees to 180 degrees; the signal processing chip 12 arranged in the cavity 111 on the back side of the base 11 can also avoid being affected by external light and electromagnetics, so that the infrared receiving module has better anti-interference ability; at the same time, the packaging volume is also reduced.

[0048] Embodiment 2:

[0049] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and implementation examples. This embodiment provides a method for manufacturing an infrared receiving module, which is used to manufacture the infrared receiving module in Example 1. Figure 2 As shown, the manufacturing method of the infrared receiving module provided in this embodiment mainly includes:

[0050] S101, manufacturing a conjoined base body, wherein the conjoined base body comprises M continuous bases, and a pad group and an inwardly concave cavity are arranged on the back of each base, wherein the pad group comprises a plurality of pads, and M is greater than or equal to 1;

[0051] S102, setting N light receiving unit groups on the front of each base, wherein the light receiving unit group includes at least one light receiving unit; setting a signal processing chip in the cavity of each base; connecting the light receiving unit, the signal processing chip, and the pad on each base;

[0052] S103, disposing a packaging layer on the front side of the integrated base body to obtain an integrated module;

[0053] S104, cutting the conjoined module to obtain M infrared receiving modules.

[0054] The order of the above steps is not limited and can be adjusted according to actual needs.

[0055] In some embodiments, during the process of making the one-piece base body in step S101, the cavity can be set in the middle area of ​​the back of the base, and the pad can be set in the edge area of ​​the back of the base, and can be set around the cavity. The base can be square, round, etc. For example, taking the base as a square, the pad group can include 4 pads, which are respectively set on the 4 feet on the back of the base.

[0056] Furthermore, in the process of making the one-piece base body in step S101, a circuit connected to the light receiving unit can be provided on the front of the base; the circuit is used to connect the light receiving unit to the signal processing chip, and the circuit and the light receiving unit can be connected by gold wire. In step S102, the circuit and the signal processing chip, and the signal processing chip and the pad can be connected through the internal vias or surface grooves of the base. This embodiment makes the overall structure more compact, reduces the volume, and improves safety.

[0057] In some embodiments, in step S102, the number of light receiving units 14 in each light receiving unit group may be the same or different, and the arrangement order of each light receiving unit group and each light receiving unit in each light receiving unit group may be determined according to user needs.

[0058] In some embodiments, in step S102, the pad group may include three pads, namely a ground pad GND, a power input pad VCC and a data output pad OUT, wherein the ground pad GND is connected to the ground terminal GND of the signal processing chip, the power input pad VCC is connected to the power input terminal VCC of the signal processing chip, and the data output pad OUT is connected to the signal output terminal OUT of the signal processing chip; the signal processing chip also has a signal input terminal IN corresponding to the light receiving unit group or the light receiving unit, and the signal input terminal IN is connected to the positive electrode of the light receiving unit corresponding thereto; the negative electrode of the light receiving unit is connected to the ground terminal GND of the signal processing chip. In some embodiments, four pads may be set on the back of the base, and in addition to the above three pads, the fourth pad is also a ground pad GND, connected to the ground terminal GND of the signal processing chip.

[0059] In some embodiments, step S103 may also include: setting a protective layer in the cavity of each base and / or on the back surface of the base, and the protective layer is used to protect the signal processing chip. The protective layer can be set in the cavity and flush with the back surface of the base; or the protective layer can be set only on the back surface of the base, covering the mouth of the cavity; or the protective layer is set in the cavity, lower than the back surface of the base; the protective layer can be set by filling the cavity with colloid, or it can be prefabricated in advance and then installed in the cavity and / or on the back surface of the base. The main function of the protective layer is to block the mouth of the cavity to prevent the signal processing chip from being affected by external forces or external environment; in some embodiments, the protective layer can further play the role of fixing the signal processing chip; in some embodiments, the protective layer can further play the role of anti-interference shielding shell to further prevent the signal processing chip from being affected by external light and electromagnetic.

[0060] In some embodiments, in step S103, the encapsulation layer can be prefabricated in advance and then installed on the front of the base; or the encapsulation layer can be formed by injection molding on the front of the base. A conjoined encapsulation layer can be set on the front of the conjoined base body, and the conjoined encapsulation layer includes multiple continuous encapsulation layers, which are divided into individual encapsulation layers after cutting in step S104. The conjoined encapsulation layer can be prefabricated in advance and then installed on the front of the conjoined base body, or the encapsulation layer can be formed by injection molding on the front of the conjoined base body.

[0061] In order to make the light receiving unit have a better light receiving effect, the packaging layer area above the light receiving unit can be made into a convex lens, so that the infrared receiving module can achieve infrared reception from 0 degrees to 180 degrees. In some embodiments, the packaging layer on the front of the base may include a first sub-packaging layer, and N second sub-packaging layers corresponding to the light receiving unit groups one by one, the second sub-packaging layer is a hemispherical protrusion, and is arranged directly above the corresponding light receiving unit group, and the first sub-packaging layer is arranged in other areas on the front of the base, wherein the first sub-packaging layer and the N second sub-packaging layers can be an integral structure.

[0062] In some embodiments, in step S103, the encapsulation layer and the protective layer of the base can be manufactured by one-time processing. The one-time manufacturing method includes but is not limited to the following:

[0063] First, in step S101, a plurality of first through holes penetrating the cavities on the front and back sides of each base need to be made;

[0064] Secondly, assuming that the device obtained after step S102 is completed is called a connected device, in step S103, a covering layer is set on the back of the connected device obtained in step S102, and the connected device provided with the covering layer is placed in a glue injection mold, the glue injection mold has an inner cavity corresponding to each of the packaging layers and having a shape matching the inner cavity, and the glue injection mold is provided with a glue injection hole; the pre-prepared colloid is injected from the glue injection hole, and the injected colloid flows to the inner cavity, and flows to the cavity through the first through hole until the inner cavity and the cavity are filled; after the colloid is solidified, the connected device after injection is taken out from the glue injection mold; the covering layer is removed to obtain the connected module.

[0065] Optionally, the covering layer includes a covering film, such as a UV film, which is mainly used to block the mouth of the cavity to prevent the colloid from flowing out of the mouth.

[0066] Optionally, the injection mold may include only an upper mold, or include an upper mold and a lower mold.

[0067] The inner chambers of the injection mold correspond to the encapsulation layers one by one. Optionally, the inner chambers of the injection mold can be connected or isolated. If the inner chambers of the injection mold are connected, step S103 includes injecting a conjoined encapsulation layer on the front side of the conjoined base body, and the conjoined encapsulation layer includes a plurality of continuous encapsulation layers.

[0068] In some embodiments, each base in the connected base body produced in step S101 includes a first circuit layer, a first insulating layer, a second circuit layer, a second insulating layer and a third circuit layer arranged from top to bottom, wherein the first circuit layer is connected to the light receiving unit; the second circuit layer is connected to the signal processing chip; the third circuit layer includes the above-mentioned pad group; the first circuit layer and the second circuit layer are connected through the internal vias or surface grooves of the first insulating layer, and the second circuit layers are connected through the internal vias or surface grooves of the second insulating layer.

[0069] Optionally, the signal processing chip is installed in the cavity on the back side of the base and is arranged on the same plane as the second circuit layer; or the signal processing chip is installed in the cavity and is arranged below the second circuit layer, adjacent to the second circuit layer.

[0070] Optionally, the base may be made of one or more plates. Taking the case where the base is made of two plates as an example, step S101 may include the following main steps:

[0071] Step A, selecting two original plates, including a first plate and a second plate;

[0072] Step B, making M first circuit layers on the front side of the first plate, making M second circuit layers on the back side of the first plate or the front side of the second plate, making M inwardly concave cavities on the back side of the second plate, and making M third circuit layers on the back side of the second plate except for the cavities, wherein the third circuit layer includes a pad group;

[0073] Step C, fixing and combining the first plate and the second plate up and down to obtain a composite plate, wherein the composite plate includes M continuous plate units, and the plate unit includes a first circuit layer, a first insulating layer, a second circuit layer, a second insulating layer and a third circuit layer stacked from top to bottom;

[0074] Step D, drilling holes at predetermined positions of the composite board to obtain multiple second through holes; setting via connectors in the through holes between the first circuit layer and the second circuit layer to connect the first circuit layer and the second circuit layer; setting via connectors in the through holes between the second circuit layer and the third circuit layer to connect the second circuit layer and the third circuit layer.

[0075] Optionally, one of the first plate and the second plate is a double-sided PCB board or a BT board; the other of the first plate and the second plate is a single-sided PCB board or a BT board or a double-sided PCB board or a BT board with one side of the circuit layer removed.

[0076] Optionally, copper foil may be deposited in the second through hole to obtain a via connector.

[0077] Optionally, the second through hole may be located inside the plate unit, or the second through hole may be located between two consecutive plate units and be shared by the two plate units.

[0078] Optionally, the first through hole and the second through hole may be shared.

[0079] In the manufacturing method of the infrared receiving module provided in this embodiment, the light receiving unit 14 is arranged on the front of the base 11, the back of the base 11 is arranged with an inwardly concave cavity 111, and the signal processing chip 12 is installed in the cavity 111. Since the signal processing chip 12 and the light receiving unit 14 are arranged on different surfaces of the base 11, the signal processing chip 12 and the light receiving unit 14 do not affect each other, which avoids the signal processing chip 12 affecting the light receiving effect of the light receiving unit 14. With the optical design of the packaging layer 13, the infrared receiving module can achieve infrared reception from 0 degrees to 180 degrees; the signal processing chip 12 arranged in the cavity 111 on the back of the base 11 can also avoid being affected by external light and electromagnetics, so that the infrared receiving module has better anti-interference ability; at the same time, the packaging volume is also reduced.

[0080] Embodiment three:

[0081] The following is a further detailed description of the specific implementation of the present invention in conjunction with the accompanying drawings and implementation examples. This embodiment provides an infrared receiving module, please refer to Figure 3 .

[0082] The infrared receiving module provided in this embodiment includes: a base, a signal processing chip 32, a packaging layer, a light receiving unit group and a protective layer 35;

[0083] The light receiving unit group includes a photodiode PD34 having an anode and a cathode;

[0084] The base is square and includes a first circuit layer 311, a first insulating layer 312, a second circuit layer 313, a second insulating layer 314 and a third circuit layer 315 arranged from top to bottom, wherein the first circuit layer 311 is connected to the photodiode PD34; the second circuit layer 313 is connected to the signal processing chip 32; the first circuit layer 311 and the second circuit layer 313 are connected by vias ( Figure 3 The second circuit layer 313 and the third circuit layer 315 are connected via a surface groove L;

[0085] A through hole is provided in the middle area of ​​the second circuit layer 313, the second insulating layer 314 and the third circuit layer 315, serving as an inwardly concave cavity 316, and the signal processing chip 32 is installed in the cavity 316 and is disposed immediately below the second circuit layer 313 and adjacent to the second circuit layer 313;

[0086] The encapsulation layer is arranged on the front side of the base, and is used to encapsulate the first circuit layer 311 and the photodiode PD34 on the front side of the base; in order to ensure the infrared receiving effect of the photodiode PD34, the encapsulation layer is not transparent; Figure 3 The encapsulation layer shown includes a first sub-encapsulation layer 331 and a second sub-encapsulation layer 332, the second sub-encapsulation layer 332 is a hemispherical protrusion, and is correspondingly arranged directly above the photodiode PD34, the first sub-encapsulation layer 331 is arranged in other areas of the front surface of the base, and the first sub-encapsulation layer 331 and the second sub-encapsulation layer 332 are an integrated structure;

[0087] The protection layer 35 is used to protect the signal processing chip 32. The protection layer 35 is provided by filling the cavity 316 with colloid, and is provided in the cavity 316 and is flush with the back surface of the second insulating layer 314.

[0088] Please refer to Figure 4 The first circuit layer 311 is disposed on the front side of the first insulating layer 312. The first circuit layer 311 has a first contact terminal 311a and a second contact terminal 311b. The first circuit layer 311 is also provided with two through holes Z. Figure 4 Only one is shown, and the other is located below the photodiode PD34. Figure 4 The through hole Z shown in FIG. 1 is located in the region of the second contact terminal 311 b and is used to connect the second contact terminal 311 b to the second circuit layer 313. Figure 4 The through hole Z not shown in the figure is located in the area of ​​the first contact terminal 311a, and is used to connect the first contact terminal 311a with the second circuit layer 313; the first contact terminal 311a is square, and the photodiode PD34 is arranged on the first contact terminal 311a. The cathode of the photodiode PD34 is located on the back of the photodiode PD34 and contacts the first contact terminal 311a. Therefore, the cathode of the photodiode PD34 is connected to the first contact terminal 311a by contacting the first contact terminal 311a, and the anode of the photodiode PD34 is connected to the second contact terminal 311b through a gold wire. The first insulating layer 312 is correspondingly provided with two through holes Z ( Figure 4 not shown);

[0089] Please refer to Figure 5 The second circuit layer 313 is arranged on the back side of the first insulating layer 312, and the second circuit layer 313 has a third contact terminal 313a, a fourth contact terminal 313b, a fifth contact terminal 313c, a sixth contact terminal 313d, and a seventh contact terminal 313e; the signal processing chip 32 in the cavity 316 is arranged adjacent to the second circuit layer 313 and below the second circuit layer 313; the signal processing chip 32 has a first signal input terminal IN1, a second signal input terminal IN2, a signal output terminal OUT, a power input terminal VCC, and a ground terminal GN D, the first signal input terminal IN1 is connected to the third contact terminal 313a through a gold wire, the signal output terminal OUT is connected to the fourth contact terminal 313b through a gold wire, the power input terminal VCC is connected to the fifth contact terminal 313c through a gold wire, the ground terminal GND is connected to the sixth contact terminal 313d through a gold wire, and the ground terminal GND is connected to the seventh contact terminal 313e through the back side at the same time, and the fourth contact terminal 313b, the fifth contact terminal 313c, the sixth contact terminal 313d, and the seventh contact terminal 313e are symmetrically arranged on the two sides of the second circuit layer 313. The second signal input terminal IN2 of the signal processing chip 32 is left blank. If two light receiving unit groups are provided on the base 31, the positive electrode of the light receiving unit of the other light receiving unit group can be connected to the second signal input terminal IN2 of the signal processing chip 32; the second circuit layer 313 is also provided with two through holes Z corresponding to and overlapping with the two through holes Z of the first circuit layer 311 and the first insulating layer 312, one is located in the area where the third contact terminal 313a is located, and the other is located in the area where the seventh contact terminal 313e is located; the second circuit layer 313 is also provided with four grooves L;

[0090] Please refer to Figure 6, the third circuit layer 315 is arranged on the back of the second insulating layer 314, and the third circuit layer 315 includes four pads, namely the first ground pad GND315a, the second ground pad GND315b, the power input pad VCC315c and the data output pad OUT315d, which are symmetrically arranged on the two sides of the back of the second insulating layer 314; in this embodiment, these four pads can be welded on the PCB board and connected to the circuit on the PCB board. These four pads are arranged on the back surface of the second insulating layer 314, which is a layer of copper foil on the back of the second insulating layer 314. The third circuit layer 315 is also provided with four grooves L corresponding to and overlapping with the four grooves L of the second circuit layer 313.

[0091] In this embodiment, the connection relationship between the photodiode PD34, the signal processing chip 32, and each pad includes:

[0092] The cathode of the photodiode PD34 is connected to the first contact terminal 311a by contacting the first contact terminal 311a, and the anode of the photodiode PD34 is connected to the second contact terminal 311b through a gold wire;

[0093] The first contact terminal 311a is connected to the seventh contact terminal 313e of the second circuit layer 313 through the via connector in the through hole Z, and is connected to the ground terminal GND of the signal processing chip 32 through the seventh contact terminal 313e; the second contact terminal 311b is connected to the third contact terminal 313a of the second circuit layer 313 through the via connector in the through hole Z, and the third contact terminal 313a is connected to the first signal input terminal IN1 of the signal processing chip 32 through a gold wire; the signal output terminal OUT of the signal processing chip 32 is connected to the fourth contact terminal 313b of the second circuit layer 313 through a gold wire, the power input terminal VCC of the signal processing chip 32 is connected to the fifth contact terminal 313c of the second circuit layer 313 through a gold wire, and the ground terminal GND of the signal processing chip 32 is also connected to the sixth contact terminal 313d of the second circuit layer 313 through a gold wire;

[0094] The fourth contact terminal 313b, the fifth contact terminal 313c, the sixth contact terminal 313d and the seventh contact terminal 313e of the second circuit layer 313 are respectively connected to the data output pad OUT315d, the power input pad VCC315c, the first ground pad GND315a and the second ground pad GND315b in the third circuit layer 314 through the groove connectors in the groove L.

[0095] The via connectors and the groove connectors may be gold wires or copper plating. Through the above connections, the connection between the photodiode PD34, the signal processing chip 32, and the pads is achieved.

[0096] The following is a method for manufacturing the infrared receiving module in this embodiment, which mainly includes:

[0097] 1. Make a one-piece base

[0098] Select two original boards: a first board and a second board, both of which are double-sided PCB boards;

[0099] Clean and dry the two double-sided PCB boards separately;

[0100] The first plate and the second plate are divided into M continuous base areas, and the following production is performed:

[0101] Etching each base area on the front side of the first plate, and manufacturing a first circuit layer in each base area;

[0102] Etching each base area on the back side of the first plate, and manufacturing a second circuit layer in each base area;

[0103] The copper foil on the front side of the second plate is removed by etching;

[0104] Etching each base area on the back side of the second plate, and manufacturing a third circuit layer, i.e., a pad group, in each base area;

[0105] Using a die, punching the middle area of ​​each base area of ​​the second plate to form a cavity;

[0106] The first plate and the second plate are stacked, wherein the first plate and the second plate are both facing upwards and the first plate is located on the second plate, and thermally pressed to obtain a composite plate, wherein the composite plate includes M continuous plate units, and the plate unit includes a first circuit layer, a first insulating layer, a second circuit layer, a second insulating layer and a third circuit layer stacked from top to bottom;

[0107] Drilling holes at predetermined positions of the composite board to obtain a plurality of through holes, wherein the through holes between the first circuit layer and the second circuit layer in the board unit communicate with the cavity;

[0108] Clean the composite sheet after drilling to remove surface debris and residue;

[0109] The composite sheet is electroplated once, and copper foil is deposited on the drilled through holes, that is, a through-hole connector is manufactured. In this embodiment, for the through hole connecting the cavity between the first circuit layer and the second circuit layer, the through hole is not filled with copper foil, and the through-hole connector only occupies half of the through hole in the longitudinal direction, and the other half of the through hole is reserved for the glue path;

[0110] The composite sheet is electroplated for a second time to achieve the desired copper foil thickness;

[0111] At this point, the manufacturing of the one-piece base body is completed, and the one-piece base body includes M continuous bases; of course, in the actual application process, the following steps may also be included:

[0112] The first circuit layer is plated with nickel, gold or silver (such as copper-nickel-gold or copper-nickel-silver) to make it easier to bond the first circuit layer and improve product reliability; the back of the base is surface treated according to the engineering drawings, such as marking the pads, etc.; the circuit connection test of the integrated base body is performed, etc.

[0113] 2. Installation of the front of the one-piece base

[0114] Photodiodes PD are installed on the front of each base, including LED chip die bonding, die bonding baking, gold wire welding, etc.

[0115] 3. Installation on the back of the one-piece base

[0116] A signal processing chip is installed in the cavity on the back of each base, including chip bonding, bonding baking, gold wire welding or reflow soldering, etc.

[0117] After completing the above step three, a conjoined device is obtained.

[0118] 4. Make the encapsulation layer and the protective layer to obtain a conjoined module

[0119] The back of the one-piece device obtained in the above step three is covered with a UV film, and the one-piece device covered with the UV film is placed in a glue injection mold, the glue injection mold has an inner cavity corresponding to each packaging layer and having a shape matching the inner cavity, and each inner cavity is connected, and the glue injection mold is provided with a glue injection hole; the pre-prepared colloid is injected from the glue injection hole, and the injected colloid flows to the inner cavity, and flows to the cavity on the back of the base through the glue channel reserved in step one until the inner cavity on the front side of the base and the cavity on the back side are filled; after the colloid is solidified, the one-piece device after the injection is taken out from the glue injection mold; the UV film is removed to obtain a one-piece module.

[0120] 5. Cut the conjoined module to obtain M infrared receiving modules

[0121] Cut from the connection of each base to obtain independent infrared receiving modules.

[0122] In the infrared receiving module and its manufacturing method provided in this embodiment, the light receiving unit is arranged on the front of the base, the back of the base is arranged with an inwardly concave cavity, and the signal processing chip is installed in the cavity. Since the signal processing chip and the light receiving unit are arranged on different surfaces of the base, the signal processing chip and the light receiving unit do not affect each other, thus avoiding the signal processing chip affecting the light receiving effect of the light receiving unit. With the optical design of the packaging layer, the infrared receiving module can achieve infrared reception from 0 degrees to 180 degrees; the signal processing chip arranged in the cavity on the back of the base can also avoid being affected by external light and electromagnetics, so that the infrared receiving module has better anti-interference ability; at the same time, the packaging volume is also reduced.

[0123] The above contents are further detailed descriptions of the embodiments of the present invention in combination with specific implementation methods, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. An infrared receiving module, comprising a base, a signal processing chip, a packaging layer, a protective layer and N light receiving unit groups, N is greater than or equal to 1, wherein: The light receiving unit group includes at least one light receiving unit, and the light receiving unit is arranged on the front side of the base; The encapsulation layer is arranged on the front side of the base, and is used to encapsulate the circuit on the front side of the base and the light receiving unit; An inwardly concave cavity is provided on the back of the base, and the signal processing chip is installed in the cavity; The protective layer is arranged in the cavity and / or on the back surface of the base to protect the signal processing chip; The base is provided with a first through hole penetrating the front and back cavities of the base; The encapsulation layer and the protective layer are formed by one-time processing by means of glue injection; A pad group is also provided on the back of the base, and the pad group includes a plurality of pads; The light receiving unit, the signal processing chip, and the pad are connected; The base includes a first circuit layer, a first insulating layer, a second circuit layer, a second insulating layer and a third circuit layer arranged from top to bottom, wherein: The first circuit layer is connected to the light receiving unit; The second circuit layer is connected to the signal processing chip; The third circuit layer includes the pad group; The first circuit layer and the second circuit layer are connected through internal via holes or surface grooves of the first insulating layer, and the second circuit layer and the third circuit layer are connected through internal via holes or surface grooves of the second insulating layer.

2. The infrared receiving module according to claim 1, characterized in that: The packaging layer includes a first sub-packaging layer and N second sub-packaging layers corresponding one by one to the light receiving unit groups, the second sub-packaging layers are hemispherical protrusions and are arranged directly above the corresponding light receiving unit groups, and the first sub-packaging layer is arranged in other areas on the front side of the base.

3. The infrared receiving module as claimed in claim 2, characterized in that: The first sub-packaging layer and the N second sub-packaging layers are an integrated structure.

4. The infrared receiving module according to claim 1, characterized in that: A circuit connected to the light receiving unit is disposed on the front side of the base, and the circuit and the signal processing chip, and the signal processing chip and the pad are connected through internal vias or surface grooves of the base.

5. The infrared receiving module according to claim 1, characterized in that: The signal processing chip is installed in the cavity and arranged on the same plane as the second circuit layer; or the signal processing chip is installed in the cavity and arranged immediately adjacent to the second circuit layer and below the second circuit layer.

6. The infrared receiving module according to claim 1, characterized in that: The base includes a first plate and a second plate arranged from top to bottom; The first plate includes a first circuit layer, a first insulating layer, and a second circuit layer, and the second plate includes a second insulating layer and a third circuit layer; the first plate is a double-sided PCB board or a BT board, the second plate is a single-sided PCB board or a BT board, or the second plate is a double-sided PCB board or a BT board with one circuit layer removed; Alternatively, the first plate includes a first circuit layer and a first insulating layer, and the second plate includes a second circuit layer, a second insulating layer and a third circuit layer; the first plate is a single-sided PCB board or a BT board, or the first plate is a double-sided PCB board or a BT board with one side of the circuit layer removed; the second plate is a double-sided PCB board or a BT board.

7. A method for manufacturing an infrared receiving module, used for manufacturing the infrared receiving module according to any one of claims 1 to 6, the method for manufacturing the infrared receiving module comprising: S101, manufacturing a conjoined base body, wherein the conjoined base body comprises M continuous bases, and a pad group and an inwardly concave cavity are arranged on the back of each base, wherein the pad group comprises a plurality of pads, and M is greater than or equal to 1; S102, setting N light receiving unit groups on the front of each base, wherein the light receiving unit group includes at least one light receiving unit; setting a signal processing chip in the cavity of each base; connecting the light receiving unit, the signal processing chip, and the pad on each base; S103, disposing a packaging layer on the front side of the integrated base body to obtain an integrated module; S104, cutting the conjoined module to obtain M infrared receiving modules according to any one of claims 1 to 6; The base includes a first circuit layer, a first insulating layer, a second circuit layer, a second insulating layer and a third circuit layer arranged from top to bottom, wherein: The first circuit layer is connected to the light receiving unit; The second circuit layer is connected to the signal processing chip; The third circuit layer includes the pad group; The first circuit layer and the second circuit layer are connected via internal via holes or surface grooves of the first insulating layer, and the second circuit layer and the third circuit layer are connected via internal via holes or surface grooves of the second insulating layer; The step S101 further includes: making a plurality of first through holes on each base that penetrate the front surface of the base and the cavity; The step S103 further includes: providing a protective layer in the cavity of each base and / or on the back surface of the base, wherein the protective layer is used to protect the signal processing chip; The packaging layer and the protective layer of the base are manufactured at one time by means of glue injection.

8. The method for manufacturing an infrared receiving module according to claim 7, characterized in that: The step S103 comprises: setting a covering layer on the back of the connected device obtained in step S102, placing the connected device provided with the covering layer into a glue injection mold, the glue injection mold having an inner cavity corresponding to each of the packaging layers and having a shape matching the inner cavity, and the glue injection mold having a glue injection hole; injecting a pre-prepared colloid from the glue injection hole, the injected colloid flows into the inner cavity, and flows into the cavity through the first through hole until the inner cavity and the cavity are filled; after the colloid is solidified, taking out the injected connected device from the glue injection mold; removing the covering layer to obtain the connected module.

9. The method for manufacturing an infrared receiving module according to claim 8, characterized in that: The inner chambers of the injection mold are connected, and the step S103 includes injecting glue on the front side of the one-piece base body to form a one-piece packaging layer, and the one-piece packaging layer includes a plurality of continuous packaging layers.

10. The method for manufacturing an infrared receiving module according to claim 7, characterized in that: The step S101 of making the one-piece base body comprises: Two original plates are selected, including a first plate and a second plate; M first circuit layers are formed on the front side of the first plate, M second circuit layers are formed on the back side of the first plate or the front side of the second plate, M inwardly concave cavities are formed on the back side of the second plate, and M third circuit layers are formed on the back side of the second plate except for the cavities, wherein the third circuit layer includes the pad group; The first plate and the second plate are fixedly combined up and down to obtain a composite plate, wherein the composite plate includes M continuous plate units, and the plate unit includes a first circuit layer, a first insulating layer, a second circuit layer, a second insulating layer and a third circuit layer stacked from top to bottom; Drill holes at predetermined positions of the composite board to obtain multiple second through holes; set a via connector in the second through hole between the first circuit layer and the second circuit layer to connect the first circuit layer and the second circuit layer; set a via connector in the second through hole between the second circuit layer and the third circuit layer to connect the second circuit layer and the third circuit layer.

11. The method for manufacturing an infrared receiving module according to claim 10, characterized in that: The second through hole is located inside the plate unit, or the second through hole is located between two consecutive plate units and is shared by the two plate units.

12. The method for manufacturing the infrared receiving module according to claim 10, characterized in that: The first through hole and the second through hole are shared.

13. The method for manufacturing an infrared receiving module according to claim 10, characterized in that: One of the first plate and the second plate is a double-sided PCB board or a BT board; the other of the first plate and the second plate is a single-sided PCB board or a BT board, or a double-sided PCB board or a BT board with one side of the circuit layer removed.

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