Light sensing device packaging structure and packaging method

Abstract

The invention provides a packaging structure and a packaging method of a light sensing device. The packaging structure comprises a substrate, a transparent molding substance, first glass and a shielding element, the substrate is provided with a first optical element and a second optical element. The transparent molding material covers the first optical element and the second optical element. A lower surface of the first glass is fixed on the transparent molding substance and is aligned with the first optical element. The shielding element covers the part, which is not covered by the first glass, of the periphery of the transparent molding substance. Therefore, a good optical sensing effect of the optical sensing device can be maintained, and the purpose of miniaturization of the whole structure is achieved.

Description

Technical Field

[0001] The present invention mainly relates to a packaging structure and a packaging method, and in particular to a packaging structure of a light sensing device provided with glass and a packaging method thereof. Background Art

[0002] Light sensing devices such as proximity sensors (PS) and ambient light sensors are widely used in portable mobile devices such as mobile phones or other consumer electronic devices. Both proximity sensors and ambient light sensors require the use of photosensitive elements, and proximity sensors generally also require the use of light-emitting elements (such as infrared transmitters or laser transmitters).

[0003] In order to provide a good optical sensing effect, some light sensing devices need to be equipped with optical filters corresponding to the light emitting elements or photosensitive elements. The easiest way to implement optical filters is to make them on glass by coating. An existing packaging method for light sensing devices with glass is to fix the glass on the cover of the light sensing device, but as the circuit area and sensor size decrease, the structure of the cover and glass will also be miniaturized. Due to the limitation of mold molding capabilities, the difficulty of fixing the miniaturized glass on the miniaturized cover made by injection molding and other methods will be greatly increased, and it is also easy to fall off.

[0004] Based on the above shortcomings, it is necessary to provide a packaging structure and packaging method for optical sensing devices such as proximity sensors and ambient light sensors to achieve the purpose of maintaining good optical sensing effects and miniaturizing the overall structure to better meet the needs of practical applications. Summary of the invention

[0005] One of the main purposes of the present invention is to provide a light sensing device packaging structure and packaging method, in particular, a light sensing device packaging structure provided with glass, which effectively avoids the problem of difficult glass fixing in the prior art by fixing the glass on the transparent molding material, and does not cause the glass to fall off as easily as in the prior art. It can maintain the good optical sensing effect of the light sensing device and achieve the purpose of miniaturizing the overall structure.

[0006] The present invention discloses a light sensing device packaging structure, including a light sensing device packaging structure, including: a substrate, on which a first optical element and a second optical element are arranged; a transparent molding material, covering the first optical element and the second optical element; a first glass, a lower surface of the first glass is fixed on the transparent molding material and is opposite to the first optical element; and a shielding element, the shielding element covers the portion of the transparent molding material that is not covered by the first glass.

[0007] The present invention further discloses a method for packaging a light sensing device, comprising: disposing a first optical element and a second optical element on a substrate; encapsulating the first optical element and the second optical element in a transparent molding material; pre-cutting the transparent molding material to open a channel space; fixing a lower surface of a first glass on the transparent molding material and aligning it with the first optical element; and filling an opaque adhesive into the channel space, and curing the opaque adhesive to form a shielding element; wherein the shielding element covers the portion of the outer periphery of the transparent molding material that is not covered by the first glass. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 FIG. 4 is a cross-sectional diagram of a light sensing device packaging structure according to the first embodiment of the present invention. Figure 2 FIG. 1 is a flow chart of an embodiment of a packaging method of a light sensing device packaging structure of the present invention. Figure 3 Schematic diagram of the steps of filling opaque glue material through a glue dispensing process in the packaging method according to an embodiment of the present invention. Figure 4 The encapsulation method according to the embodiment of the present invention is a schematic diagram of the steps of filling an opaque adhesive material through a mold injection process. Figure 5A FIG. 4 is a schematic diagram of the coating configuration of the light sensing device packaging structure according to an embodiment of the present invention. Figure 5B FIG. 2 is a schematic diagram of another coating configuration of the light sensing device packaging structure according to an embodiment of the present invention. Figure 6 It is a schematic diagram showing that the light sensing device packaging structure according to an embodiment of the present invention is applicable to various glass structures. Figure 7 FIG. 4 is a cross-sectional diagram of a light sensing device packaging structure according to a second embodiment of the present invention.

Figure number comparison

[0009] In order to further understand and appreciate the structural features and effects of the present invention, a preferred embodiment and detailed description are provided as follows:

[0010] Figure 1 Schematic cross-sectional view of a light sensing device packaging structure of the first embodiment of the present invention. The light sensing device packaging structure includes a substrate 10, a first optical element 11 and a second optical element 12, a transparent molding material 2, a first glass 31 and a second glass 32, and a shielding element 4. The first optical element 11 and the second optical element 12 can be light-emitting elements or photosensitive elements, respectively, and the light-emitting elements are generally infrared emitters or laser emitters. The photosensitive element is generally an application specific integrated circuit (ASIC), which is manufactured through an integrated circuit process and can include a photosensitive element and an operating circuit (for example, a photosensitive element and an operating circuit of a proximity sensor and / or an ambient light sensor).

[0011] In detail, if the light sensing device packaging structure is used as a proximity sensor, the proximity sensor usually includes at least one light emitting element and one photosensitive element. Therefore, the first optical element 11 and the second optical element 12 can be a light emitting element and a photosensitive element, respectively. Alternatively, in order to provide specific functions, some proximity sensors or other light sensing devices may need to set up multiple light emitting elements of different wavelengths. Therefore, the first optical element 11 and the second optical element 12 can be light emitting elements, respectively. Alternatively, if the light sensing device packaging structure is used as an ambient light sensor, some ambient light sensors may need to set up multiple photosensitive elements at the same time in order to sense advanced optical sensing results such as color temperature, and each photosensitive element requires a different optical filter. Therefore, the first optical element 11 and the second optical element 12 can be photosensitive elements, respectively. Of course, if the light sensing device packaging structure is to integrate a proximity sensor and an ambient light sensor, it usually includes at least two light emitting elements and a photosensitive element, so the optical elements set in the light sensing device packaging structure are not limited to the first optical element 11 and the second optical element 12.

[0012] like Figure 1As shown, the first optical element 11 and the second optical element 12 are disposed on the substrate 10, wherein the first optical element 11 and the second optical element 12 can be connected to the substrate 10 through wires made by wire bonding. However, in addition to the conventional wire bonding process, the first optical element 11 or the second optical element 12 can also be connected to the substrate 10 through other methods, and the present invention is not limited thereto. In one embodiment, the substrate 10 is a copper foil substrate, a ceramic substrate, a wire bracket, a resin substrate or a printed circuit board, and the wires made by wire bonding can be gold wires, but are not limited thereto.

[0013] The first optical element 11 and the second optical element 12 are encapsulated and sealed in a transparent molding substance 2, and the first glass 31 and the second glass 32 are respectively fixed on the transparent molding substance 2. In detail, the first glass 31 includes a lower surface 31a, and the lower surface 31a of the first glass 31 can be attached and fixed on the transparent molding substance 2 and aligned with the first optical element 11. The second glass 32 includes a lower surface 32a, and the lower surface 32a of the second glass 32 can be attached and fixed on the transparent molding substance 2 and aligned with the second optical element 12.

[0014] The first glass 31 and the second glass 32 can be used to make an optical filter, for example, an optical filter that allows light of a specific wavelength to pass through, or allows light of a specific polarization direction to pass through, is formed on the first glass 31 and the second glass 32 in a coating manner. The optical filter can be formed by stacking different material structures on the first glass 31 and the second glass 32, for example, by setting a single layer or multiple layers of coating, optical microstructures, etc. to make the optical filter. Alternatively, the optical filter can also be formed by doping the first glass 31 and the second glass 32 with dyes. Of course, the optical filter can also be a mixture of the above two structures.

[0015] The shielding element 4 is made of an opaque material, and the shielding element 4 can cover the portion of the outer periphery of the transparent molding material 2 that is not covered by the first glass 31 and the second glass 32, and keep the first glass 31 and the second glass 32 exposed. In the case of limited space, in order to reduce the crosstalk between the first optical element 11 and the second optical element 12, the shielding element 4 of the first embodiment of the present invention can form a wall 41 between the first optical element 11 and the second optical element 12 to prevent light from being transmitted between the first optical element 11 and the second optical element 12. In this case, the transparent molding material 2 is divided into a first part 21 and a second part 22 by the wall 41. The first part 21 seals the first optical element 11, and the first glass 31 is fixed to the first part 21. The second part 22 seals the second optical element 12, and the second glass 32 is fixed to the second part 22.

[0016] The following will describe how to manufacture the light sensing device packaging structure of the first embodiment using the packaging method of the light sensing device packaging structure of the present invention. Figure 2 This is a schematic diagram of a packaging method according to an embodiment of the present invention. In an embodiment of a packaging method for a light sensing device packaging structure according to the present invention:

[0017] First, a first optical element 11 and a second optical element 12 are disposed on a substrate 10 .

[0018] The first optical element 11 and the second optical element 12 are encapsulated and sealed in a transparent molding material 2. For example, a liquid transparent adhesive (such as a transparent resin) is injected into a mold, and after solidification, the transparent molding material 2 is formed, and the mold is removed to encapsulate the first optical element 11 and the second optical element 12 in the transparent molding material 2.

[0019] Next, the transparent molding material 2 is pre-cut to reserve the slot space 23 for the shielding element 4 to be set later. In detail, since the light sensing device packaging structure of the present invention is preferably packaged in a continuous process, it is difficult to reserve the slot space 23 for forming the transparent molding material 2 only by a mold. Figure 1 The first channel space 23a of the shielding element 4 shown in the figure is not formed, so it is necessary to perform this pre-cutting step to open the corresponding first channel space 23a. Furthermore, the transparent molding material 2 formed by the mold may not be flat enough to allow the first glass 31 and the second glass 32 to be attached and fixed, so performing this pre-cutting step can also process the surface flatness of the transparent molding material 2. In addition, if the shielding element 4 forms a wall 41 between the first optical element 11 and the second optical element 12, performing this pre-cutting step can open the second channel space 23b in the transparent molding material 2 for forming the wall 41, and this second channel space 23b separates the transparent molding material 2 into the first part 21 and the second part 22.

[0020] The first glass 31 and the second glass 32 are fixed to the transparent molding material 2 respectively through a transparent colloid (e.g., transparent adhesive) or other fixing means. Note that if the position where the glass is to be fixed does not need to be cut, and if the user does not consider the risk of the cutting tool damaging the first glass 31 and the second glass, the order of this glass fixing step and the aforementioned pre-cutting step can be exchanged.

[0021] The opaque adhesive is filled into the channel space 23 formed by the aforementioned pre-cutting, and after the opaque adhesive is cured and the redundant part is cut and ground as needed, the shielding element 4 is formed. As mentioned above, the shielding element 4 covers the portion of the outer periphery of the transparent molding material 2 that is not covered by the first glass 31 and the second glass 32, and leaves the first glass 31 and the second glass 32 exposed. The opaque adhesive selected in this embodiment is, for example, epoxy resin, silicone, a mixture of resin and silicone, and acrylic adhesive, and the opaque adhesive can be a black epoxy resin or other material that is opaque in itself, or the opaque adhesive can be made opaque by doping dyes, carbon black, silicon dioxide, titanium dioxide or other fillers. In this way, the shielding element 4 formed after the opaque adhesive is cured has a light-shielding effect.

[0022] Please refer to Figure 3 FIG. 2 is a schematic diagram showing how to fill the opaque adhesive material 5 into the groove space 23 formed by the pre-cutting by the dispensing process. The opaque adhesive material 5 is preferably a material that is liquid at room temperature, so that the liquid opaque adhesive material 5 can be dropped into the groove space 23 formed by the pre-cutting without heating or applying special pressure. The advantage of this method is that no redundant parts may be generated, so the shielding element 4 can be formed without additional cutting and grinding.

[0023] Please refer to Figure 4 FIG. 2 is a schematic diagram showing a process of injecting the opaque adhesive material 5 into the groove space 23 formed by the pre-cutting. The advantage of mold injection is that it is easy to heat and pressurize, so there is no need to select a material that is liquid at room temperature, and mold injection does not require additional alignment, and the production speed is usually faster, which can improve the overall process efficiency.

[0024] Finally, since the light sensing device packaging structure of the present invention is preferably packaged in a continuous manner, the shielding element 4 and the substrate 10 can be cut to form independent finished products.

[0025] In summary, the light sensing device packaging structure and packaging method of the first embodiment of the present invention provide a light sensing device packaging structure with glass, which effectively avoids the problem of the prior art that it is difficult to fix the glass on the cover by fixing the glass on the transparent molding material. Moreover, by fixing the glass to the transparent molding material and then providing a shielding element on the transparent molding material and the outside of the glass, the position of the glass can be effectively fixed, so the glass will not fall off as easily as in the prior art. Accordingly, the light sensing device packaging structure and packaging method of the first embodiment of the present invention can maintain a good optical sensing effect of the light sensing device and achieve the purpose of miniaturizing the overall structure.

[0026] It is worth noting that, as mentioned above, the easiest way to realize an optical filter is to set a single layer or multiple layers of coating to make it on the first glass 31 and the second glass 32, which is additionally explained as follows. After the opaque adhesive is cured, it may be necessary to cut and grind the redundant parts to form the shielding element 4. The first glass 31 and the second glass 32 are used to make an optical filter. If the optical filter is coated on the surface of the first glass 31 and the second glass 32, there is a risk of damaging the optical filter by cutting and grinding the cured opaque adhesive. Therefore, please refer to Figure 5A As shown, in this case, it is recommended to form an optical filter only on the lower surface 31 a of the first glass 31 and the lower surface 32 a of the second glass 32 by coating.

[0027] Alternatively, please refer to Figure 5B As shown, if a method is selected that does not require cutting and grinding of the opaque adhesive to form the shielding element 4 (such as the aforementioned dispensing process), or the user assesses that cutting and grinding of the opaque adhesive will not damage the optical filter, an optical filter can still be formed by coating on an upper surface 31b of the first glass 31 and an upper surface 32b of the second glass 32.

[0028] The following further describes other beneficial effects of the light sensing device packaging structure and packaging method according to the embodiment of the present invention:

[0029] As described above, as the size of the sensor is reduced, the structure of the cover and the glass will also be miniaturized. For the miniaturized glass structure, whether it is to be assembled to the cover or other miniaturized structures, the difficulty of the process will be greatly increased. Therefore, the technical effect achieved by the miniaturized sensor using the embodiment of the present invention is particularly significant. Furthermore, the number of glass structures that need to be assembled will also affect the difficulty of the assembly process, so the technical effect achieved by the embodiment of the present invention using the sensor that requires the use of more glass structures is particularly significant (for example, a light sensing device having multiple light-emitting elements or multiple photosensitive elements at the same time).

[0030] In addition to the impact of size and quantity, the shape and consistency of the glass structure will affect the complexity of the process of assembling it into the cover or other miniaturized structures. However, please refer to Figure 6 As shown, for the light sensing device packaging structure and packaging method of the embodiment of the present invention, because the glass structure is fixed on the transparent molding material, and then the shielding element is made. Therefore, no matter what shape of glass is used, and no matter whether each glass structure is consistent, it does not affect the implementation of the embodiment of the present invention. Compared with the prior art, which also takes into account the complexity of the process, the implementation of the present invention has obvious advantages.

[0031] Also, please continue to refer to Figure 1As shown, because the embodiment of the present invention directly fixes the glass structures 31 and 32 on the transparent molding substance 2, there will be no gap between the glass structures 31 and 32 and the transparent molding substance 2. In contrast, other prior arts that also have transparent molding substances mostly fix the glass structure on a cover or other components separated from the transparent molding substance, resulting in a gap between the glass structure and the transparent molding substance in the prior art. The existence of the gap and the uncertainty of its size may affect the optical sensing effect of the prior art. In contrast, the light sensing device packaging structure and the packaging method thereof using the embodiment of the present invention do not have such problems and can maintain a good optical sensing effect to the greatest extent.

[0032] In addition, please continue to refer to Figure 2 As shown, when performing the pre-cutting step to form the second channel space 23b for forming the wall 41 in the transparent molding material 2, if the cutting is too deep, the first optical element 11 and the second optical element 12 may be damaged. Therefore, one solution is to reserve a certain degree of transparent molding material 2 without cutting; another solution is to refer to the Taiwan Patent No. I779739 applied by the applicant to form an opaque material 41a that can completely prevent light from being transmitted between the first optical element 11 and the second optical element 12. Since it is not the technical content of the present invention, it will not be further described here.

[0033] Finally, please refer to Figure 7 , which is a cross-sectional schematic diagram of a light sensing device packaging structure of the second embodiment of the present invention. Although in the light sensing device packaging structure and the packaging method of the first embodiment of the present invention, a first glass 31 and a second glass 32 are respectively provided corresponding to the first optical element 11 and the second optical element 12. However, it can be understood by those with ordinary knowledge in the relevant technical field that in some cases, the second optical element 12 may not need an optical filter, and thus it is not necessary to provide the second glass 32 for it. Therefore, if further cost saving is to be achieved, in the second embodiment of the present invention, only the first glass 31 needs to be provided corresponding to the first optical element 11. Accordingly, in order to avoid the occurrence of depressions in the light sensing device packaging structure, a convex portion 221 can be reserved at the position of the second optical element 12 (i.e., the position of the second glass 32 in the first embodiment) when the transparent molding material 2 is pre-cut. In this way, when the second glass 322 is omitted, the other parts of the light sensing device packaging structure and the packaging method of the second embodiment of the present invention can remain unchanged.

[0034] In summary, the light sensing device packaging structure and packaging method of each embodiment of the present invention provide a light sensing device packaging structure with glass. By fixing the glass on the transparent molding material, the problem of the prior art that it is difficult to fix the glass on the cover body is effectively avoided. The glass will not fall off easily like the prior art, and the light sensing device can maintain a good optical sensing effect and achieve the purpose of miniaturizing the overall structure.

[0035] The order of execution of each step in the above embodiment does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present application.

[0036] The above is only a preferred embodiment of the present invention and is not intended to limit the scope of the present invention. All equivalent changes and modifications to the shape, structure, characteristics and spirit described in the claims of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A light sensing device packaging structure, It is characterized in that include: a substrate on which a first optical element and a second optical element are disposed; A transparent molding material, covering the first optical element and the second optical element; a first glass, a lower surface of which is fixed on the transparent molding material and is aligned with the first optical element; and A shielding element covers the portion of the transparent molding material that is not covered by the first glass.

2. The light sensing device packaging structure as claimed in claim 1, It is characterized in that The shielding element includes a wall formed between the first optical element and the second optical element.

3. The light sensing device packaging structure as claimed in claim 2, It is characterized in that The transparent molding material is divided into a first part and a second part by the wall, the first part covers the first optical element, the first glass is fixed on the first part, and the second part covers the second optical element.

4. The light sensing device packaging structure as claimed in claim 1, It is characterized in that The first glass is used for making optical filters.

5. The light sensing device packaging structure as claimed in claim 4, It is characterized in that The optical filter is formed on the lower surface of the first glass in a coating manner.

6. The light sensing device packaging structure as claimed in claim 1, It is characterized in that A second glass is also included, a lower surface of which is fixed on the transparent molding material and faces the second optical element, and the shielding element covers the outer portion of the transparent molding material that is not covered by the first glass and the second glass.

7. The light sensing device packaging structure as claimed in claim 6, It is characterized in that The shielding element includes a wall formed between the first optical element and the second optical element.

8. The light sensing device packaging structure as claimed in claim 7, It is characterized in that The transparent molding material is divided into a first part and a second part by the wall, the first part covers the first optical element, and the first glass is fixed to the first part, the second part covers the second optical element, and the second glass is fixed to the second part.

9. The light sensing device packaging structure as claimed in claim 6, It is characterized in that The first glass and the second glass are used to make optical filters.

10. The light sensing device packaging structure as claimed in claim 9, It is characterized in that The lower surface of the first glass and the lower surface of the second glass are respectively coated to form the optical filter.

11. A method for packaging a light sensing device, It is characterized in that Include: A first optical element and a second optical element are disposed on a substrate; Encapsulating the first optical element and the second optical element in a transparent molding material; Pre-cutting the transparent molding material to open a channel space; Fixing a lower surface of a first glass on the transparent molding material and aligned with the first optical element; and Filling an opaque adhesive into the channel space, and curing the opaque adhesive to form a shielding element; The shielding element covers the portion of the transparent molding material that is not covered by the first glass.

12. The light sensing device packaging method as claimed in claim 11, It is characterized in that in, The pre-cutting step includes opening a second channel space in the transparent molding material for forming a wall of the shielding element, the second channel space separates the transparent molding material into a first part and a second part, the first part covers the first optical element, and the first glass is fixed to the first part, and the second part covers the second optical element.

13. The light sensing device packaging method as claimed in claim 11, It is characterized in that in, The first glass is fixed on the transparent molding material via a transparent colloid.

14. The method for packaging a light sensing device as claimed in claim 11, It is characterized in that in, After the opaque adhesive material is cured, the redundant portion of the opaque adhesive material is cut and ground to form the shielding element.

15. The method for packaging a light sensing device as claimed in claim 11, It is characterized in that in, The method also includes cutting the shielding element and the substrate so that the light sensing device packaging structures are formed independently.

16. The method for packaging a light sensing device as claimed in claim 11, It is characterized in that in, The method further comprises manufacturing an optical filter from the first glass.

17. The method for packaging a light sensing device as claimed in claim 11, It is characterized in that in, The method further comprises fixing a lower surface of a second glass on the transparent molding material and aligning the second optical element, wherein the shielding element covers the portion of the transparent molding material that is not covered by the first glass and the second glass.

18. The method for packaging a light sensing device as claimed in claim 17, It is characterized in that in, The pre-cutting step includes opening a second channel space in the transparent molding material for forming a wall of the shielding element, the second channel space separating the transparent molding material into a first part and a second part, the first part enclosing the first optical element, and the first glass is fixed to the first part, the second part enclosing the second optical element, and the second glass is fixed to the second part.

19. The method for packaging a light sensing device as claimed in claim 17, It is characterized in that in, The invention also includes manufacturing an optical filter with the first glass and the second glass.

20. The method for packaging a light sensing device as claimed in claim 19, It is characterized in that The optical filter is formed on the lower surface of the first glass and the lower surface of the second glass respectively by coating.

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