A package structure of an electronic device

Abstract

The application discloses a packaging structure of an electronic device, which comprises a substrate, an optical device fixedly connected to the substrate, an upper surface of the optical device having an optical area for receiving and / or transmitting an optical signal, a cover sealedly connected to the upper surface of the optical device and surrounding the optical area, the cover having an opening, and a transparent inner cover arranged inside the opening and sealing the opening, the upper surface of the optical device, the cover and the transparent inner cover being sealedly enclosed to form a cavity, and the optical signal passing between the optical area and the outside of the packaging structure through the opening and the transparent inner cover. The application provides a small-cavity packaging structure, which is not easy to damage the cavity sealing even when the air in the cavity expands due to heat.

Description

Technical Field

[0001] This invention relates to the field of electronic component packaging, and more particularly to a packaging structure for electronic components. Background Technology

[0002] In the prior art, large cavity packaging is often used in packaging structures that include optical components. Figure 1 Taking the Ball Grid Array (BGA) package as an example, a schematic diagram of a large cavity package structure in the prior art is shown. Figure 1 The BGA package substrate shown has optical components, other chips, resistors / capacitors, and other electronic components soldered onto it. The optical components have optical areas on their upper surface and are connected to the substrate pads via leads. An opaque outer casing is fixed to the upper surface of the substrate to seal the optical components and other components above the substrate within a cavity inside the casing. The upper part of the casing has an opening, and a light-transmitting glass sheet is fixed to the outside of the opening of the casing with adhesive, allowing external light to enter the optical areas of the optical components through the light-transmitting glass sheet.

[0003] However, since electronic components often generate heat during operation, this large-cavity packaging method contains a large amount of air inside the cavity. When the air is heated, it expands and can easily break the adhesive at the connection between the transparent glass sheet and the outer cover, damaging the sealing of the packaging structure. This can lead to problems such as air leakage and water ingress, which can not only affect the refractive index and reduce the quality and stability of optical signal transmission, but may also damage the electronic components inside the packaging structure or shorten their service life, affecting product reliability. Summary of the Invention

[0004] To address the aforementioned technical problems, the purpose of this invention is to provide a new packaging structure to solve the problem that large-cavity packaging structures in the prior art are easily damaged.

[0005] This invention provides a packaging structure for an electronic device, comprising: a substrate and an optical device fixedly connected to the substrate, the upper surface of the optical device having an optical region for receiving and / or transmitting optical signals; an outer cover that is sealed to the upper surface of the optical device and surrounds the optical region, the outer cover having an opening; and a transparent inner cover disposed inside the opening and sealing the opening, the upper surface of the optical device, the outer cover and the transparent inner cover sealingly enclosing a cavity, the optical signal path between the optical region and the outside of the packaging structure passing through the opening and the transparent inner cover.

[0006] In some embodiments, the upper surface of the optical device has an annular groove located outside the optical region, and the bottom of the outer cover is embedded in the annular groove and sealed to the optical device by an adhesive material.

[0007] In some embodiments, the annular groove includes a first annular groove and a second annular groove, the first annular groove being sleeved outside the second annular groove, and the bottom of the outer cover being embedded inside the second annular groove.

[0008] In the above embodiments, the annular groove may further include a third annular groove, with the second annular groove sleeved outside the third annular groove.

[0009] In some embodiments, the annular groove includes a second annular groove and a third annular groove, with the second annular groove sleeved outside the third annular groove and the bottom of the outer cover embedded in the second annular groove.

[0010] In some embodiments, the outer wall of the outer cover is provided with a raised structure, which can be bonded to the insulating encapsulation material to form a whole.

[0011] In the above embodiments, the protrusion structure can be an annular protrusion surrounding the outer wall of the outer cover.

[0012] In some embodiments, the protrusion structure is a slope shape with the inner side lower than the outer side or vice versa.

[0013] In some embodiments, the area of ​​the opening is larger than the area of ​​the optical region.

[0014] In some embodiments, the outer cover is made of a metallic material.

[0015] In the above embodiments, the packaging structure of the electronic device may further include an insulating packaging layer, with the outer cover encapsulated within the insulating packaging layer and an opening exposed.

[0016] The small cavity packaging structure used in this invention has the following advantages:

[0017] (1) The cavity is small and contains less air, so the packaging structure is not easily damaged even if it expands due to heat.

[0018] (2) The transparent inner cover is set inside the opening of the outer cover, which further avoids the risk of the air in the cavity expanding due to heat and pushing it open, thereby damaging the cavity's airtightness. Attached Figure Description

[0019] Figure 1 A schematic diagram of a large cavity packaging structure in the prior art is shown;

[0020] Figure 2 A schematic diagram of the packaging structure 1 according to an embodiment of the present invention is shown;

[0021] Figure 3A It shows Figure 2 Top view of optical component 20;

[0022] Figure 3B It shows along Figure 3AA cross-sectional view along the AA direction;

[0023] Figure 4 A schematic diagram of the packaging structure 1 according to another embodiment of the present invention is shown;

[0024] Figure 5A It shows Figure 4 Top view of optical component 20;

[0025] Figure 5B It shows along Figure 4 A sectional view along the AA direction in section A. Detailed Implementation

[0026] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the invention in any way. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. These modifications and improvements all fall within the scope of protection of the present invention.

[0027] Figure 2 A schematic diagram of the packaging structure 1 of an electronic device according to an embodiment of the present invention is shown. Figure 2 As shown, the packaging structure 1 includes a substrate 10, an optical device 20, an outer cover 30, and a transparent inner cover 40.

[0028] The substrate 10 serves as a carrier for the electronic components in the packaging structure 1 and provides electrical connections for them. Depending on actual needs, the shape of the upper surface of the substrate 10 can be various, such as circular, rectangular, or elliptical, and the substrate 10 can be made of materials such as plastic or ceramic.

[0029] The optical device 20 is fixedly connected to the substrate 10, and can be connected using adhesives such as glue or sintering materials, for example, epoxy resin adhesive. In some embodiments, the optical device 20 can be fixedly connected to the substrate 10 using sintering materials 51 such as sintered silver or sintered copper to enhance its robustness. The upper surface of the optical device 20 has an optical region 21. In this disclosure, the optical region 21 can be any component capable of emitting and / or receiving light signals, and the light carrying the light signals can be visible or invisible, with a corresponding wavelength range from 10 nm to 1 mm.

[0030] The outer casing 30 is sealed to the upper surface of the optical device 20 and surrounds the optical region 21, and the outer casing 30 has an opening 31. External light signals can enter the optical region 21 through the opening 31, or light signals emitted by the optical region 21 can illuminate the outside through the opening 31. The opening 31 can be located at the top of the outer casing 30, such as... Figure 2 and Figure 4As shown, in other embodiments, the opening 31 may also be provided at other locations on the outer cover 30 as needed, such as the side of the outer cover 30, as long as the light signal can be incident on the optical area 21 or emitted from the optical area 21 to the outside.

[0031] The outer cover 30 can be made of various materials with a certain degree of rigidity. In some embodiments, the outer cover 30 is made of metal material to achieve good electromagnetic shielding and good heat dissipation.

[0032] In some embodiments, the outer cover 30 and the upper surface of the optical device 20 are sealed together using adhesive materials such as adhesive or sintering materials.

[0033] In some embodiments, to achieve a more secure connection between the outer cover 30 and the upper surface of the optical device 20, an annular groove 22 can be provided on the outer side of the optical region 21 on the upper surface of the optical device 20, such as... Figure 3A and Figure 3B As shown. Among them, Figure 3A It shows Figure 2 Top view of optical component 20. Figure 3B It shows along Figure 3A Cross-sectional view along the AA direction. See also Figure 2 The bottom of the outer cover 30 is embedded in the annular groove 22, and sintering material 51 is sintered into the annular groove 22 through a sintering process, thereby achieving a firm and sealed connection with the optical device 20. The sintering material 51 can be various types of materials suitable for sintering processes, such as sintered silver or sintered copper. To ensure the sealing of the connection between the outer cover 30 and the upper surface of the optical device 20, the sintering material 51 should fill the entire groove 22 as much as possible. It should be noted that the top view shape of the annular groove 22 should match the shape of the bottom of the outer cover 30. Although Figure 3A The groove 22 shown is an example of a square annular shape, but this is merely exemplary, and those skilled in the art can set the annular groove 22 to other shapes that match the bottom of the outer cover 30 according to specific needs.

[0034] In some embodiments, to prevent adhesive or sintering material 51 from contaminating other areas of the optical device 20, two or more annular grooves 22 may be provided on the outer side of the optical area 21. Figure 4 A schematic diagram of the packaging structure 1 according to another embodiment of the present invention is shown. Figure 5A It shows Figure 4 Top view of optical component 20. Figure 5B It shows along Figure 4 A cross-sectional view along direction AA in section A. For example... Figure 5A and Figure 5BAs shown, in some embodiments, the number of annular grooves 22 is at least two, including a first annular groove 22a and a second annular groove 22b, both disposed outside the optical region 21, with the first annular groove 22a sleeved over the second annular groove 22b. In some embodiments, the annular groove 22 includes a second annular groove 22b and a third annular groove 22c, both disposed outside the optical region 21, with the second annular groove 22b sleeved over the third annular groove 22c. In other embodiments, the number of annular grooves 22 is at least three, including a first annular groove 22a, a second annular groove 22b, and a third annular groove 22c. For the above embodiments, see [link to documentation]. Figure 4 The bottom of the outer cover 30 is embedded in the second annular groove 22b, and the sintering material 51 is sintered into the second annular groove 22b through a sintering process. In this way, even if the sintering material 51 may overflow outside the second annular groove 22b during the sintering process, the first annular groove 22a and / or the third annular groove 22c on both sides can contain the overflowing sintering material 51 and prevent it from continuing to spread and contaminate other areas.

[0035] A transparent inner cover 40, made of transparent material, is disposed inside the opening 31 and seals the opening 31, such as... Figure 2 and Figure 4 As shown. The transparent inner cover 40 can be sealed to the inside of the opening 31 of the outer cover 30 by means of adhesive or other methods. Since the transparent inner cover 40 is located inside the opening 31, even if the air inside the cavity sealed by the transparent inner cover 40, the outer cover 30 and the upper surface of the optical device 20 expands due to heat, it cannot break the seal between the transparent inner cover 40 and the outer cover 30, thereby greatly improving the reliability of the product.

[0036] The optical signal path between the optical region 21 and the outside of the packaging structure 1 passes through the opening 31 and the transparent inner cover 40. In some embodiments, the area of ​​the opening 31 is larger than the area of ​​the optical region 21, which allows the optical region 21 to receive external incident light signals with a wider angle range, thereby making the product more adaptable and making fuller use of the optical region 21.

[0037] In one or more embodiments, such as Figure 2As shown, the electronic device packaging structure 1 also includes an insulating packaging layer 60. The outer cover 30 is encapsulated within the insulating packaging layer 60 and exposes the opening 31, so that an optical signal path can be formed between the optical region 21 and the outside of the packaging structure 1. The upper surface of the optical device 20, the outer cover 30, and the transparent inner cover 40 seal and enclose a cavity 70. Other components, such as other chips, resistors / capacitors, etc., are located outside the cavity 70. In this way, the components above the substrate 10 and outside the outer cover 30 can be encapsulated within the insulating packaging layer 60, which can provide insulation, dustproof, waterproof, anti-oxidation, and fixation. The packaging material can be selected from plastics, epoxy resins, polysulfides, polyurethane, silicone, etc.

[0038] Additionally, in some embodiments, to better secure the outer casing 30 within the insulating encapsulation layer 60, such as... Figure 4 As shown, a protruding structure 32 can be provided on the outer wall of the outer casing 30. The protruding structure 32 is embedded in the insulating encapsulation layer 60, which can increase the adhesion between the outer casing 30 and the insulating encapsulation layer 60, making them more firmly bonded into a whole. At the same time, the fixing effect of the insulating encapsulation layer 60 can enhance the sealing connection between the outer casing 30 and the upper surface of the optical device 20, further preventing the outer casing 30 from loosening from the upper surface of the optical device 20. In some embodiments, the protruding structure 32 is an annular protrusion surrounding the outer wall of the outer casing 30 to further increase the adhesion between the outer casing 30 and the insulating encapsulation layer 60. To obtain better structural strength, in some embodiments, the protruding structure 32 and the outer casing 30 are integrally formed. Figure 4 In the illustrated embodiment, the outer wall of the outer cover 30 is perpendicular to the upper surface of the substrate 10, and the protruding structure 32 is a ring-shaped surface perpendicular to the outer wall of the outer cover 30 and parallel to the upper surface of the substrate 10. In other embodiments, the protruding structure may not be parallel to the upper surface of the substrate. For example, the protruding structure 32 may be a slope with a lower inner slope and a higher outer slope, or vice versa. That is, the part of the protruding structure 32 that connects to the outer cover 30 is lower or higher than the part away from the outer cover 30. This can better enhance the adhesion between the outer cover and the insulating encapsulation layer, and also enhance the structural strength of the outer cover itself, preventing the protruding structure 32 from breaking at its root. In some embodiments, the number of protruding structures 32 may be multiple to further enhance the adhesion between the outer cover 30 and the insulating encapsulation layer 60.

[0039] It should be pointed out that, although Figure 2 and Figure 4 The invention uses BGA packaging as an example for illustration, but it is not limited to BGA packaging and can be applied to any situation where optical devices need to be packaged.

[0040] This invention utilizes a small-cavity packaging structure to place the outer cover on the upper surface of the optical device, minimizing the volume of the inner cavity within the cover and thus reducing the volume of the cover material and lowering packaging costs. Furthermore, by placing a transparent inner cover inside the outer cover opening, this invention avoids the risk of air inside the inner cavity expanding due to heat and bursting open the transparent inner cover. Additionally, by creating a groove on the upper surface of the optical device and sintering the bottom of the outer cover into the groove, this invention ensures a secure connection between the outer cover and the upper surface of the optical device. These technical solutions effectively address the poor airtightness problem caused by large-cavity packaging in existing technologies.

[0041] Those skilled in the art can understand and implement other modifications to the disclosed embodiments by reading the specification, the disclosure, the drawings, and the appended claims. In the claims, the word "comprising" does not exclude other elements and steps, and the words "a" or "an" do not exclude a plurality. In practical applications of this application, a single part may perform the function of multiple technical features referenced in the claims. Any reference numerals in the claims should not be construed as limiting the scope.

Claims

1. A packaging structure for an electronic device, characterized in that, include: A substrate and an optical device fixedly connected to the substrate, wherein the upper surface of the optical device has an optical area for receiving and / or transmitting optical signals; An outer cover, which is sealed to the upper surface of the optical device and surrounds the optical region, the outer cover having an opening; as well as A transparent inner cover is disposed inside the opening and seals the opening. The transparent inner cover is connected to the inner surface of the outer cover facing the upper surface of the optical device. The upper surface of the optical device, the outer cover, and the transparent inner cover seal and enclose a cavity. The optical signal path between the optical region and the outside of the packaging structure passes through the opening and the transparent inner cover. The optical device has an annular groove on its upper surface, which is located outside the optical area. The bottom of the outer cover is embedded in the annular groove and is sealed to the optical device by an adhesive material.

2. The packaging structure as described in claim 1, characterized in that, The annular groove includes a first annular groove and a second annular groove, with the first annular groove sleeved outside the second annular groove and the bottom of the outer cover embedded inside the second annular groove.

3. The packaging structure as described in claim 2, characterized in that, The annular groove further includes a third annular groove, and the second annular groove is sleeved outside the third annular groove.

4. The packaging structure as described in claim 1, characterized in that, The annular groove includes a second annular groove and a third annular groove. The second annular groove is sleeved outside the third annular groove, and the bottom of the outer cover is embedded in the second annular groove.

5. The packaging structure as described in claim 1, characterized in that, The outer wall of the outer cover is provided with a raised structure, which can be bonded to the insulating encapsulation material to form a whole.

6. The packaging structure as described in claim 5, characterized in that, The protrusion structure is an annular protrusion surrounding the outer wall of the outer cover.

7. The packaging structure as described in claim 6, characterized in that, The protruding structure is a sloping shape, either lower on the inside and higher on the outside or higher on the inside and lower on the outside.

8. The packaging structure as described in claim 1, characterized in that, The area of ​​the opening is larger than the area of ​​the optical region.

9. The packaging structure as described in claim 1, characterized in that, The outer cover is made of metal.

10. The packaging structure according to any one of claims 1-9, characterized in that, The packaging structure of the electronic device further includes an insulating packaging layer, and the outer cover is encapsulated within the insulating packaging layer and exposes the opening.

Images