Packaging structure of optical sensor and manufacturing method thereof

Abstract

This invention relates to the field of photoelectric sensor technology, and discloses a packaging structure and manufacturing method for an optical sensor. The packaging structure of the optical sensor includes: a main substrate, a light-collecting chip, a sub-substrate, a light-emitting chip, a light-transmitting plastic encapsulation layer, and a light-blocking adhesive wall. The main substrate has a blind slot; the light-collecting chip is disposed in the blind slot and has a light-collecting portion; the sub-substrate is at least partially disposed on the light-collecting chip and has a clearance portion that is vertically opposite to the light-collecting portion; the light-emitting chip is disposed on the sub-substrate, and the light-emitting chip and the clearance portion are arranged at intervals; the light-transmitting plastic encapsulation layer is disposed on the light-collecting portion, the sub-substrate, and the light-emitting chip, and a groove is formed in the light-transmitting plastic encapsulation layer between the light-emitting chip and the clearance portion; the light-blocking adhesive wall is disposed in the groove and connects to the sub-substrate. By embedding the light-collecting chip, the thickness space of the sensor is fully utilized, and the partial overlap reduces the planar space occupied by the sub-substrate outside the light-collecting chip, thereby simplifying the manufacturing process while improving product integration.

Description

Technical Field

[0001] This invention relates to the field of photoelectric sensor technology, and in particular to a packaging structure and manufacturing method for an optical sensor. Background Technology

[0002] Currently, optical sensors, including lidar, proximity sensors, and ambient light sensors, are widely used in consumer electronics, autonomous driving, industrial robots, and other fields. Their principle is to receive light signals, convert them into electrical signals, and analyze and process these electrical signals to obtain the target physical quantity.

[0003] For example, Chinese invention patent application CN112768561A discloses a light sensor packaging structure and manufacturing method. The light sensor packaging structure includes a substrate, a molding compound, and a packaging shell. A light sensor unit is disposed on the substrate. The light sensor unit includes a light receiver and a light emitter. Both the light receiver and the light emitter are wrapped by the molding compound. The molding compound is divided into left and right parts by a first isolation groove, which is formed by cutting. The packaging shell covers the molding compound. The sidewalls of the packaging shell are made of opaque material and wrap the molding compound. The packaging shell also has a first isolation wall located in the first isolation groove between the light receiver and the light emitter to block the light path between the light emitter and the light receiver of each light sensor unit in the packaging structure.

[0004] In existing optical sensor packaging structures, the outer shell is made of opaque plastic material through injection molding, and then glue is used to combine the outer shell with the encapsulated body. However, injection molding requires high precision and the assembly process is relatively complex; moreover, the light receiver and light emitter occupy two independent spaces in the substrate plane, resulting in low product integration. Summary of the Invention

[0005] The technical problem to be solved by the present invention is that existing optical sensors have high requirements for injection molding precision of the packaging shell, the assembly process is relatively complex, and the optical receiver and the optical transmitter occupy two independent spaces in the substrate plane, resulting in low product integration.

[0006] To address the aforementioned technical problems, this invention provides a technical solution for the packaging structure of an optical sensor: The packaging structure of optical sensors includes: The main substrate has a blind slot, and a first circuit layer is also provided on the back side of the main substrate; A light-collecting chip is disposed in the blind slot, and the chip has a light-collecting section; A sub-substrate is at least partially disposed on the light-receiving chip. The sub-substrate has a clearance portion that is vertically opposite to the light-receiving portion. A second circuit layer is disposed on the surface of the sub-substrate, and the second circuit layer is electrically connected to the first circuit layer and the light-receiving chip. A light-emitting chip is disposed on the sub-substrate and electrically connected to the second circuit layer, and the light-emitting chip and the clearance portion are arranged at intervals. A light-transmitting plastic sealant is disposed on the light-receiving part, the sub-substrate and the light-emitting chip, and the light-transmitting plastic sealant has a groove between the light-emitting chip and the clearance part; A light-blocking adhesive wall is provided within the groove and connected to the sub-substrate.

[0007] Furthermore, the sub-substrate has a recessed groove, the groove is connected vertically to the recessed groove, and the light-blocking adhesive wall is filled in the groove and the recessed groove using a dispensing process.

[0008] Furthermore, the surface of the sub-substrate is provided with a void area, which is located between the clearance portion and the second circuit layer, and the sink is provided in the void area.

[0009] Furthermore, the light-collecting part is disposed on one side of the surface of the light-collecting chip, the light-emitting chip is disposed on the side of the sub-substrate away from the clearance part, and the light-emitting chip, the sub-substrate and the light-collecting chip are stacked sequentially from top to bottom.

[0010] Furthermore, the main substrate has a first through hole, which is spaced apart from the blind slot, and the sub-substrate has a second through hole; the first through hole and the second through hole are filled with conductors, and the conductors electrically connect the first circuit layer and the second circuit layer.

[0011] Furthermore, the packaging structure of the optical sensor also includes an adhesive layer, which is disposed between the light-receiving chip and the sub-substrate, and the adhesive layer avoids the light-receiving portion; the adhesive layer also fills the gap between the light-receiving chip and the blind slot.

[0012] Furthermore, the adhesive layer is formed from a semi-cured PP sheet through a hot melt pressing process.

[0013] Furthermore, the packaging structure of the optical sensor also includes an ink layer, which is disposed on the first circuit layer and / or the second circuit layer. The ink layer has a window, and the second circuit layer forms a pad corresponding to the window.

[0014] To address the aforementioned technical problems, this invention provides a technical solution for fabricating a packaging structure for an optical sensor: The method for fabricating the packaging structure of an optical sensor includes the following steps: S1. Form a first circuit layer on the back side of the main substrate and process blind trenches on the surface of the main substrate. S2. Apply a protective film to the light-receiving part of the light-receiving chip, place the light-receiving chip in the blind slot and fix it. S3. A clearance portion is processed on the sub-substrate, and the sub-substrate is bonded to the light-collecting chip by hot-melt pressing with a semi-cured PP sheet, so that the light-collecting portion of the light-collecting chip is exposed through the clearance portion. S4. A second through hole is processed on the sub-substrate, and a conductor is filled into the second through hole. A second circuit layer is formed on the surface of the sub-substrate. The second circuit layer is electrically connected to the light-receiving chip and the first circuit layer through a conductor. S5. Cover the second circuit layer with an ink layer, and form the connection part and pad of the light-emitting chip by etching to open the window; S6. Place the light-emitting chip in the connection part of the light-emitting chip in the second circuit layer, and connect the light-emitting chip and the pad by wire bonding. S7. Remove the protective film from the light-receiving part and encapsulate the light-receiving part, sub-substrate and light-emitting chip to form a transparent plastic sealing layer; S8. A groove is cut into the portion of the light-transmitting plastic sealant between the light-emitting chip and the clearance portion, and the bottom of the groove contacts the sub-substrate; S9. Apply adhesive into the groove and allow it to cure to form a light-blocking adhesive wall.

[0015] Furthermore, in steps S1 to S9, both the main substrate and the sub-substrate are integral substrates; the method for manufacturing the packaging structure of the optical sensor further includes: after dispensing adhesive in step S10, the integral optical sensor semi-finished product is then cut to obtain at least two finished optical sensor products.

[0016] Compared with the prior art, the method for manufacturing an optical sensor packaging structure according to the present invention has the following advantages: the packaging structure of the optical sensor adopts a design of a main substrate, a light-collecting chip, a sub-substrate, a light-emitting chip, a light-transmitting plastic encapsulation layer, and a light-blocking adhesive wall. The main substrate has a blind slot, and the light-collecting chip is disposed in the blind slot. The main substrate provides a reliable structural foundation for the light-collecting chip. Without affecting the structural strength, the thickness space of the main substrate can be fully utilized by accommodating the light-collecting chip through the blind slot, thereby reducing the thickness of the entire optical sensor product.

[0017] The light-receiving chip has a light-receiving section that receives light signals from the environment. A sub-substrate is at least partially disposed on the light-receiving chip, and the sub-substrate has a clearance section that corresponds vertically to the light-receiving section. By arranging the sub-substrate on the light-receiving chip with at least partial vertical overlap, the planar space occupied by the sub-substrate outside the light-receiving chip is reduced. The sub-substrate provides the structural foundation for the light-receiving chip, and the clearance section of the sub-substrate provides a light path for the light-receiving section, ensuring that the light signal propagates smoothly to the light-receiving section without interference from the sub-substrate.

[0018] Furthermore, a light-transmitting molding layer is disposed on the light-receiving part, the sub-substrate, and the light-emitting chip. A groove is provided between the light-emitting chip and the clearance part in the light-transmitting molding layer, and a light-blocking adhesive wall is disposed within the groove and connected to the sub-substrate. By covering and encapsulating the surfaces of the light-receiving part, the sub-substrate, and the light-emitting chip with the light-transmitting molding layer, it not only effectively prevents external moisture, dust, and other contaminants from corroding the chip and circuitry, but also ensures unobstructed light paths for both emitted and received light signals. The light-blocking adhesive wall is formed by flow-fill bonding. Compared to assembly processes, the flowability of the light-blocking adhesive allows for the formation of a complete light barrier between the light-emitting chip and the light-receiving part, preventing light signal interference within the sensor caused by assembly gaps and thus ensuring product yield while simplifying the manufacturing process.

[0019] In addition, a first circuit layer is provided on the back of the main substrate, and a second circuit layer is provided on the surface of the sub-substrate. The second circuit layer is electrically connected to the first circuit layer and the light-receiving chip. The light-emitting chip is disposed on the sub-substrate and is electrically connected to the second circuit layer. The light-emitting chip and the light-receiving chip are electrically connected to the first circuit layer through the second circuit layer. On the back of the main substrate, electrical signals can be smoothly transmitted to the control module, and electrical signals controlling the light emission can be transmitted to the light-emitting chip, as well as electrical signals converted from ambient light signals can be received.

[0020] The packaging structure of this optical sensor fully utilizes the thickness and planar space of the sensor through a collaborative design that includes an embedded light-receiving chip, at least partial overlap between the sub-substrate and the light-receiving chip, vertical alignment between the clearance portion and the light-receiving portion, and a groove in the light-blocking adhesive wall that fills the light-transmitting plastic sealant. This reduces the total area occupied by the light receiving end and the light emitting end in the plane of the substrate, thereby simplifying the manufacturing process while improving the product integration. Attached Figure Description

[0021] Figure 1 This is a cross-sectional schematic diagram of the packaging structure of the optical sensor according to an embodiment of the present invention; Figure 2 This is a schematic diagram of step S1 (making the first circuit layer) of the method for manufacturing the packaging structure of the optical sensor according to an embodiment of the present invention; Figure 3 This is a schematic diagram of step S1 (processing a blind groove) of the method for manufacturing the packaging structure of the optical sensor according to an embodiment of the present invention; Figure 4 This is a schematic diagram of step S2 of the method for manufacturing the packaging structure of the optical sensor according to an embodiment of the present invention; Figure 5 This is a schematic diagram of step S3 (before hot melt pressing) of the method for manufacturing the packaging structure of the optical sensor according to an embodiment of the present invention; Figure 6This is a schematic diagram of step S4 (processing the second through hole) of the method for manufacturing the packaging structure of the optical sensor according to an embodiment of the present invention; Figure 7 This is a schematic diagram of step S4 (filling conductor) of the method for manufacturing the packaging structure of the optical sensor according to an embodiment of the present invention; Figure 8 This is a schematic diagram of step S4 (making the second circuit layer) of the method for manufacturing the packaging structure of the optical sensor according to an embodiment of the present invention; Figure 9 This is a schematic diagram of step S5 (covering the ink layer) of the method for manufacturing the packaging structure of the optical sensor according to an embodiment of the present invention; Figure 10 This is a schematic diagram of step S6 in the method for fabricating the packaging structure of the optical sensor according to an embodiment of the present invention. Figure 11 This is a schematic diagram of step S7 of the method for manufacturing the packaging structure of the optical sensor according to an embodiment of the present invention; Figure 12 This is a schematic diagram of step S8 of the method for manufacturing the packaging structure of the optical sensor according to an embodiment of the present invention; Figure 13 This is a schematic diagram of step S9 of the method for manufacturing the packaging structure of the optical sensor according to an embodiment of the present invention; Figure 14 This is a schematic diagram of step S10 of the method for manufacturing the packaging structure of the optical sensor according to an embodiment of the present invention; In the figure: 1. Main substrate; 11. Blind slot; 12. First circuit layer; 13. First through hole; 14. Conductor; 2. Light-collecting chip; 21. Light-collecting part; 3. Sub-substrate; 31. Clearance part; 32. Second circuit layer; 33. Sink; 34. Empty area; 35. Second through hole; 36. Ink layer; 37. Pad; 4. Light-emitting chip; 5. Transparent plastic encapsulation layer; 51. Groove; 6. Light-blocking adhesive wall; 7. Adhesive layer; 1a. Whole main substrate; 3a. Whole sub-substrate; 4a. Whole optical sensor semi-finished product; 5a. Optical sensor finished product. Detailed Implementation

[0022] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0023] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise" used to indicate orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0025] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0026] like Figure 1 As shown, the packaging structure of the optical sensor in this embodiment of the invention includes: a main substrate 1, a light-receiving chip 2, a sub-substrate 3, a light-emitting chip 4, a light-transmitting plastic encapsulation layer 5, and a light-blocking adhesive wall 6; the main substrate 1 has a blind slot 11, and a first circuit layer 12 is also provided on the back side of the main substrate 1; the light-receiving chip 2 is disposed in the blind slot 11, and the light-receiving chip 2 has a light-receiving part 21; the sub-substrate 3 is at least partially disposed on the light-receiving chip 2, and the sub-substrate 3 has a clearance part 31, which is vertically opposite to the light-receiving part 21; a second circuit layer 32 is provided on the surface of the sub-substrate 3, and the second circuit layer 32 is electrically connected to the first circuit layer 12 and the light-receiving chip 2.

[0027] The light-emitting chip 4 is disposed on the sub-substrate 3 and electrically connected to the second circuit layer 32. The light-emitting chip 4 and the clearance portion 31 are arranged at intervals. The light-transmitting plastic sealant 5 is disposed on the light-receiving portion 21, the sub-substrate 3 and the light-emitting chip 4. The light-transmitting plastic sealant 5 is located between the light-emitting chip 4 and the clearance portion 31 and has a groove 51. The light-blocking adhesive wall 6 is provided in the groove 51 and is connected to the sub-substrate 3.

[0028] The packaging structure of this optical sensor adopts a design of main substrate 1, light-collecting chip 2, sub-substrate 3, light-emitting chip 4, light-transmitting plastic encapsulation layer 5, and light-blocking adhesive wall 6. The main substrate 1 has a blind slot 11, and the light-collecting chip 2 is located in the blind slot 11. The main substrate 1 provides a reliable structural foundation for the light-collecting chip 2. Without affecting the structural strength, the thickness space of the main substrate 1 can be fully utilized by accommodating the light-collecting chip 2 through the blind slot 11, thereby reducing the thickness of the entire optical sensor product 5a.

[0029] The light-receiving chip 2 has a light-receiving section 21, which receives light signals from the environment. The sub-substrate 3 is at least partially disposed on the light-receiving chip 2, and the sub-substrate 3 has a clearance section 31 that corresponds vertically to the light-receiving section 21. By arranging the sub-substrate 3 on the light-receiving chip 2 with at least partial vertical overlap, the planar space occupied by the sub-substrate 3 outside the light-receiving chip 2 is reduced. The sub-substrate 3 provides the structural foundation for the light-receiving chip 2, and the clearance section 31 of the sub-substrate 3 reserves an optical path for the light-receiving section 21, ensuring that the light signal is not interfered with by the sub-substrate 3 and can be smoothly propagated to the light-receiving section 21.

[0030] Furthermore, a light-transmitting plastic sealant layer 5 is disposed on the light-receiving part 21, the sub-substrate 3, and the light-emitting chip 4. A groove 51 is provided between the light-emitting chip 4 and the clearance part 31 in the light-transmitting plastic sealant layer 5. A light-blocking adhesive wall 6 is disposed within the groove 51 and connected to the sub-substrate 3. By covering and encapsulating the surfaces of the light-receiving part 21, the sub-substrate 3, and the light-emitting chip 4 with the light-transmitting plastic sealant layer 5, not only is external moisture and dust effectively prevented from corroding the chip and circuitry, but it also ensures that the light path for emitting light signals and receiving light signals from the environment remains unobstructed. The light-blocking adhesive wall 6 is formed by flow-filling bonding. Compared to assembly processes, the flowability of the light-blocking adhesive allows for the formation of a complete light barrier between the light-emitting chip 4 and the light-receiving part 21, preventing light signal interference inside the sensor due to assembly gaps and thus ensuring product yield while simplifying the manufacturing process.

[0031] In addition, a first circuit layer 12 is provided on the back side of the main substrate 1, and a second circuit layer 32 is provided on the surface of the sub-substrate 3. The second circuit layer 32 is electrically connected to the first circuit layer 12 and the light-receiving chip 2. The light-emitting chip 4 is disposed on the sub-substrate 3 and is electrically connected to the second circuit layer 32. The light-emitting chip 4 and the light-receiving chip 2 are electrically connected to the first circuit layer 12 through the second circuit layer 32. On the back side of the main substrate 1, electrical signals can be smoothly transmitted with the control module, and electrical signals controlling the light emission can be transmitted to the light-emitting chip 4, as well as electrical signals converted from ambient light signals can be received.

[0032] The packaging structure of this optical sensor utilizes a collaborative design that incorporates an embedded light-receiving chip 2, a sub-substrate 3 that at least partially overlaps with the light-receiving chip 2, an avoidance portion 31 that corresponds vertically to the light-receiving portion 21, and a light-blocking adhesive wall 6 that fills the groove 51 of the light-transmitting plastic sealant layer 5. This design fully utilizes the thickness and planar space of the sensor, reduces the total area occupied by the light receiving end and the light emitting end in the plane of the substrate, and achieves the goal of simplifying the manufacturing process while improving product integration.

[0033] In this embodiment, the sub-substrate 3 has a recessed groove 33, and the groove 51 is vertically connected to the recessed groove 33. The light-blocking adhesive wall 6 is filled into the groove 51 and the recessed groove 33 using a dispensing process. Specifically, the depth of the recessed groove 33 is equal to half the thickness of the sub-substrate 3, which not only ensures a reliable connection between the light-blocking adhesive wall 6 and the sub-substrate 3, but also reduces the risk of light leakage due to cracks in the light shielding by embedding it at the bottom. In some embodiments of this application, the depth of the recessed groove 33 can also be one-third, one-quarter, or one-fifth of the thickness of the sub-substrate 3, or any size between one-fifth and one-half.

[0034] The sub-substrate 3 also has a void area 34 on its surface, which is located between the clearance portion 31 and the second circuit layer 32. The sink 33 is located in the void area 34. The upper surface of the sub-substrate 3 originally has a copper layer (the second circuit layer 32 is formed through processes such as lamination, exposure, development, etching and stripping). The void area 34 is an area that exposes the sub-substrate 3 and does not belong to the second circuit layer 32. This area serves as the space for the light-blocking adhesive wall 6, preventing the formation of the sink 33 from damaging the integrity of the second circuit layer 32, and improving the connection reliability between the light-blocking adhesive wall 6 and the sub-substrate 3.

[0035] It should be noted that the light-collecting part 21 is disposed on one side of the surface of the light-collecting chip 2, and the light-emitting chip 4 is disposed on the side of the sub-substrate 3 away from the avoidance part 31. The light-emitting chip 4, the sub-substrate 3, and the light-collecting chip 2 are stacked sequentially from top to bottom. For example, the light-collecting part 21 is disposed on the left side of the surface of the light-collecting chip 2, and the light-emitting chip 4 is disposed on the right side of the sub-substrate 3. Through the staggered left and right and overlapping top and bottom distribution, the problem of stacking interference light path is effectively avoided.

[0036] As a further preferred embodiment, the main substrate 1 has a first through-hole 13, which is spaced apart from the blind slot 11. The sub-substrate 3 has a second through-hole 35. The first through-hole 13 and the second through-hole 35 are filled with conductors 14, and the conductors 14 electrically connect the first circuit layer 12 and the second circuit layer 32. The first through-hole 13 and the second through-hole 35 are formed by mechanical drilling or laser drilling, and the conductors 14 are copper pillars, which realizes the purpose of cross-layer electrical connection between the light-receiving chip 2, the light-emitting chip 4, the first circuit layer 12, and the second circuit layer 32.

[0037] In this embodiment, the optical sensor's packaging structure further includes an adhesive layer 7, which is disposed between the light-receiving chip 2 and the sub-substrate 3, and avoids the light-receiving portion 21; the adhesive layer 7 also fills the gap between the light-receiving chip 2 and the blind slot 11. Specifically, the adhesive layer 7 is formed by a semi-cured PP sheet through a hot melt pressing process. During the hot melt pressing process, the fluidity of the semi-cured PP material is used to fill the complex gaps between the main substrate 1, the light-receiving chip 2, and the sub-substrate 3, and the bonding reliability is better.

[0038] In addition, the packaging structure of the optical sensor also includes an ink layer 36, which is disposed on the first circuit layer 12 and / or the second circuit layer 32. The ink layer 36 has a window, and the second circuit layer 32 forms a pad 37 corresponding to the window. The ink layer 36 is an insulating ink layer, which can provide insulation protection for the first circuit layer 12 on the back of the main substrate 1 and the second circuit layer 32 on the surface of the sub-substrate 3. The connection part of the light-emitting chip 4 and the pad 37 are exposed by etching the window. The pad 37 constitutes the connection point for wire bonding between the light-emitting chip 4 and the second circuit layer 32. Nickel or gold can be plated inside the window to play a role in preventing surface oxidation.

[0039] The method for fabricating the packaging structure for the aforementioned optical sensor includes the following steps: It should be noted that in this embodiment, both the main substrate 1 and the sub-substrate 3 are whole substrates, namely a whole main substrate 1a and a whole sub-substrate 3a, respectively, achieving the purpose of mass production of optical sensor finished product 5a. In some embodiments of this application, the main substrate 1 and the sub-substrate 3 can also be substrates for single products, eliminating the slitting process in step S10, and only one optical sensor finished product 5a can be produced.

[0040] S1, such as Figure 2 As shown, a first circuit layer 12 is formed on the back side of the entire main substrate 1a. The specific process is as follows: the upper and lower surfaces of the entire main substrate 1a originally have copper layers. First, the moisture is dried to eliminate the stress of the entire main substrate 1a to prevent warping and reduce the expansion and contraction deformation of the board. Then, the copper layer is thinly etched to remove surface oxides, reduce the thickness of the surface copper and roughen the surface to facilitate the formation of the first circuit layer 12.

[0041] A first through hole 13 is machined into the entire main substrate 1a. This can be achieved by mechanical drilling or laser drilling. The hole serves as a conductive path between the upper and lower surfaces or as a positioning hole and process hole required for other processes. The drilled hole is then filled with copper plating (i.e., conductor 14) to connect the copper layers of the upper and lower surfaces.

[0042] After electroplating, a dry film is first applied to the copper surface. The pattern of the first circuit layer 12 is then formed on the dry film through exposure and development. Excess copper is then etched away, and finally the dry film is peeled off to obtain the desired first circuit layer 12. In this embodiment, a pattern transfer process is used to fabricate the first circuit layer 12. In some embodiments of this application, a semi-additive process (SAP) or a modified semi-additive process (mSAP) can also be used.

[0043] like Figure 3 As shown, a blind groove 11 is machined on the surface of the entire main substrate 1a. The blind groove 11 can be machined by mechanical drilling or laser forming. It should be noted that the entire main substrate 1a is not broken at the blind groove 11; there are still substrates connecting the blind groove 11 around its perimeter.

[0044] S2. Apply a protective film to the light-receiving part 21 of the light-receiving chip 2. A water-soluble thin film can be used to cover the light-receiving part 21 to prevent surface contamination during subsequent processes. Figure 4 As shown, the light-receiving chip 2 is placed in the blind slot 11 and fixed using glue or adhesive.

[0045] S3. A clearance portion 31 is processed on the entire sub-substrate 3a. Specifically, the upper surface of the entire sub-substrate 3a originally has a copper layer, and the clearance portion 31 is a through groove that penetrates the entire substrate 3a. For example Figure 5 As shown, a semi-cured PP sheet is used to heat-melt press the entire sub-substrate 3a onto the light-collecting chip 2, resulting in a composite substrate with an upper frame. The light-collecting portion 21 of the light-collecting chip 2 is exposed through the clearance portion 31. During the heat-melt pressing process, the fluidity of the semi-cured PP material is used to fill the complex gaps between the entire main substrate 1a, the light-collecting chip 2, and the entire sub-substrate 3a, resulting in better bonding reliability.

[0046] S4, such as Figure 6 As shown, a second through hole 35 is processed on the entire sub-substrate 3a; as Figure 7 As shown, conductor 14 is filled into the second through hole 35; as Figure 8 As shown, a second circuit layer 32 is formed on the surface of the entire sub-substrate 3a. The second circuit layer 32 is electrically connected to the light-receiving chip 2 and the first circuit layer 12 through a conductor 14. The fabrication process of the second circuit layer 32 is the same as that of the first circuit layer 12, and will not be described again here.

[0047] S5, such as Figure 9As shown, an ink layer 36 is applied to the second circuit layer 32, and the connection portion and pad 37 of the light-emitting chip 4 are formed by etching to create windows. The ink layer 36 is an insulating ink layer, which can provide insulation protection for the first circuit layer 12 on the back of the entire main substrate 1a and the second circuit layer 32 on the surface of the entire sub-substrate 3a. The connection portion and pad 37 of the light-emitting chip 4 are exposed by etching to create windows. The pad 37 forms the connection point for wire bonding between the light-emitting chip 4 and the second circuit layer 32. Nickel or gold can be plated inside the window to prevent surface oxidation.

[0048] S6, such as Figure 10 As shown, the light-emitting chip 4 is placed in the connection part of the light-emitting chip 4 on the second circuit layer 32, and the light-emitting chip 4 and the pad 37 are wire-connected.

[0049] S7. Remove the protective film from the light-receiving section 21, such as... Figure 11 As shown, a light-transmitting plastic encapsulation layer 5 is formed on the light-receiving part 21, the whole sub-substrate 3a and the light-emitting chip 4.

[0050] S8, such as Figure 12 As shown, a groove 51 is cut into the portion of the light-transmitting plastic sealant 5 between the light-emitting chip 4 and the clearance portion 31, and the bottom of the groove 51 contacts the entire substrate 3a.

[0051] S9, such as Figure 13 As shown, adhesive is applied into the groove 51 and cured to form a light-blocking adhesive wall 6.

[0052] S10. After dispensing, the entire optical sensor semi-finished product 4a is cut into at least two optical sensor finished products 5a.

[0053] The specific embodiments of the method for manufacturing the packaging structure of the optical sensor of the present invention are the same as the specific embodiments of the method for manufacturing the packaging structure of the optical sensor of the present invention described above, and will not be repeated here.

[0054] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A packaging structure for an optical sensor, characterized in that, include: The main substrate (1) has a blind slot (11) and a first circuit layer (12) is provided on the back side of the main substrate (1). A light-collecting chip (2) is disposed in the blind slot (11), and the light-collecting chip (2) has a light-collecting part (21). A sub-substrate (3) is at least partially disposed on the light-receiving chip (2). The sub-substrate (3) has a clearance portion (31) which is vertically opposite to the light-receiving portion (21). A second circuit layer (32) is disposed on the surface of the sub-substrate (3). The second circuit layer (32) is electrically connected to the first circuit layer (12) and the light-receiving chip (2). A light-emitting chip (4) is disposed on the sub-substrate (3) and electrically connected to the second circuit layer (32). The light-emitting chip (4) and the clearance portion (31) are arranged at intervals. A light-transmitting plastic seal layer (5) is disposed on the light-receiving part (21), the sub-substrate (3) and the light-emitting chip (4). The light-transmitting plastic seal layer (5) has a groove (51) between the light-emitting chip (4) and the clearance part (31). The light-blocking adhesive wall (6) is provided in the groove (51) and connected to the sub-substrate (3).

2. The packaging structure of the optical sensor according to claim 1, characterized in that, The sub-substrate (3) has a recessed groove (33), the groove (51) is connected to the recessed groove (33) vertically, and the light-blocking adhesive wall (6) is filled in the groove (51) and the recessed groove (33) by dispensing adhesive.

3. The packaging structure of the optical sensor according to claim 2, characterized in that, The surface of the sub-substrate (3) is also provided with a vacancy area (34), which is located between the avoidance part (31) and the second circuit layer (32), and the sink (33) is provided in the vacancy area (34).

4. The packaging structure of the optical sensor according to any one of claims 1 to 3, characterized in that, The light-collecting part (21) is disposed on one side of the surface of the light-collecting chip (2), and the light-emitting chip (4) is disposed on the side of the sub-substrate (3) away from the avoidance part (31), and the light-emitting chip (4), the sub-substrate (3) and the light-collecting chip (2) are stacked sequentially from top to bottom.

5. The packaging structure of the optical sensor according to any one of claims 1 to 3, characterized in that, The main substrate (1) has a first through hole (13), the first through hole (13) and the blind slot (11) are arranged at intervals, and the sub-substrate (3) has a second through hole (35); the first through hole (13) and the second through hole (35) are filled with conductors (14), and the conductors (14) are electrically connected to the first circuit layer (12) and the second circuit layer (32).

6. The packaging structure of the optical sensor according to any one of claims 1 to 3, characterized in that, The packaging structure of the optical sensor also includes an adhesive layer (7), which is disposed between the light-collecting chip (2) and the sub-substrate (3), and the adhesive layer (7) avoids the light-collecting part (21); the adhesive layer (7) also fills the gap between the light-collecting chip (2) and the blind slot (11).

7. The packaging structure of the optical sensor according to claim 6, characterized in that, The adhesive layer (7) is formed by hot melt pressing of a semi-cured PP sheet.

8. The packaging structure of the optical sensor according to any one of claims 1 to 3, characterized in that, The packaging structure of the optical sensor also includes an ink layer (36), which is disposed on the first circuit layer (12) and / or the second circuit layer (32). The ink layer (36) has a window, and the second circuit layer (32) forms a pad (37) corresponding to the window.

9. A method for fabricating a packaging structure for the optical sensor of claim 1, characterized in that, Includes the following steps: S1. A first circuit layer (12) is formed on the back side of the main substrate (1), and a blind groove (11) is formed on the surface of the main substrate (1). S2. Apply a protective film to the light-receiving part (21) of the light-receiving chip (2), place the light-receiving chip (2) in the blind slot (11) and fix it. S3. A clearance portion (31) is processed on the sub-substrate (3). The sub-substrate (3) is bonded to the light-collecting chip (2) by hot-melt pressing of a semi-cured PP sheet. The light-collecting portion (21) of the light-collecting chip (2) is exposed through the clearance portion (31). S4. A second through hole (35) is processed on the sub-substrate (3), and a conductor (14) is filled into the second through hole (35). A second circuit layer (32) is made on the surface of the sub-substrate (3). The second circuit layer (32) is electrically connected to the light receiving chip (2) and the first circuit layer (12) through the conductor (14). S5. Cover the second circuit layer (32) with an ink layer (36) and form the connection part and pad (37) of the light-emitting chip (4) by etching to open the window. S6. Place the light-emitting chip (4) on the connection part of the light-emitting chip (4) in the second circuit layer (32), and connect the light-emitting chip (4) and the pad (37) by wire bonding; S7. Remove the protective film from the light-collecting part (21) and encapsulate the light-collecting part (21), the sub-substrate (3) and the light-emitting chip (4) to form a transparent plastic sealing layer (5). S8. A groove (51) is cut into the portion of the light-transmitting plastic sealant (5) between the light-emitting chip (4) and the clearance portion (31), and the bottom of the groove (51) contacts the sub-substrate (3). S9. Apply adhesive to the groove (51) and cure to form a light-blocking adhesive wall (6).

10. The method for fabricating the packaging structure of the optical sensor according to claim 9, characterized in that, In steps S1 to S9, both the main substrate (1) and the sub-substrate (3) are whole substrates; the method for manufacturing the packaging structure of the optical sensor further includes: after step S10 and dispensing, the whole optical sensor semi-finished product (4a) is cut to obtain at least two finished optical sensor products (5a).

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