Optical sensor module and method of manufacturing the same

Abstract

A light sensor module and a method of manufacturing the same are disclosed. The light sensor module includes a support layer, one or more light sensor cells, a plurality of conductive pillars, and a patterned light blocking layer. The support layer has opposing upper and lower surfaces. The light sensor cells are disposed on the upper surface of the support layer. The conductive pillars extend through the support layer. The conductive pillars electrically connect the light sensor cells. The patterned light blocking layer is positioned over the light sensor cells, wherein the patterned light blocking layer has openings positioned directly over the light sensor cells.

Description

Technical Field

[0001] This invention relates to an optical sensor module and a method for manufacturing the optical sensor module. Background Technology

[0002] In existing technologies, to package an optical sensor module containing a light-emitting element and a photosensitive element, wire-bonded light-emitting element and photosensitive element are typically selected, and they are jointly disposed on a semiconductor substrate. The light-emitting element and photosensitive element are then sealed together with a transparent molding material. This provides protection for the light-emitting element and photosensitive element without affecting the transmission of light signals. Further optimizations are then made to incorporate other optical structures or to optimize the package size to meet the product's optical communication requirements.

[0003] To meet the trend of increasingly thinner designs in consumer electronics, further miniaturizing the overall package size of optical sensor modules has become a top priority in product development. Manufacturers are exploring various methods to reduce the size of optical sensor modules, including the light-emitting and photosensitive elements. However, in existing technologies, the wire-bonded light-emitting and photosensitive elements already occupy a certain volume, and they still require molding material encapsulation for necessary protection and fixation. This structure significantly limits further reductions in thickness or size of the packaged optical sensor module.

[0004] In view of the above, there is a need to provide an improved structure and manufacturing process for the optical sensor module to achieve overall miniaturization, so as to better meet the needs of practical applications. Summary of the Invention

[0005] This invention provides a light sensor module, comprising a support layer, one or more light sensor units, multiple conductive pillars, and a patterned light-shielding layer. The support layer has opposing upper and lower surfaces. The light sensor units are disposed on the upper surface of the support layer. The conductive pillars penetrate the upper surface of the support layer and extend to the lower surface. The conductive pillars are electrically connected to the light sensor units. The patterned light-shielding layer is located above the light sensor units, wherein the patterned light-shielding layer has an opening located directly above the light sensor units.

[0006] In some embodiments, the optical sensor module further includes an insulating layer disposed between the optical sensor unit and the patterned light-shielding layer, and the thickness of the insulating layer is 1 micrometer to 5 micrometers.

[0007] In some embodiments, the optical sensor unit has multiple contacts, and each conductive post directly contacts each contact.

[0008] In some embodiments, the patterned light-shielding layer includes silicon, metal, or photoresist.

[0009] In some embodiments, when the patterned light-shielding layer is silicon, the thickness of the patterned light-shielding layer is 10 micrometers to 30 micrometers or 20 micrometers to 40 micrometers.

[0010] In some embodiments, when the patterned light-shielding layer is metal, the thickness of the patterned light-shielding layer is 0.1 micrometers to 3 micrometers.

[0011] In some embodiments, when the patterned light-shielding layer is a photoresist, the thickness of the patterned light-shielding layer is 2 micrometers to 8 micrometers or 3 micrometers to 5 micrometers.

[0012] The present invention also provides a method for manufacturing a photosensitive module, comprising the following steps: forming an etch stop layer on a substrate; forming a photosensitive unit on the etch stop layer; forming a plurality of conductive pillars on the photosensitive unit; filling a support material between the plurality of conductive pillars to form a support layer; and forming a patterned light-shielding layer on the photosensitive unit, such that the photosensitive unit is sandwiched between the patterned light-shielding layer and the support layer.

[0013] In some embodiments, forming a patterned light-shielding layer includes: thinning a substrate; and etching the substrate to form an opening such that the opening is located directly above the light sensor unit.

[0014] In some embodiments, forming a patterned light-shielding layer includes: removing a substrate to expose an etch stop layer; forming a patterned mask on the exposed etch stop layer; and etching the patterned mask to form a patterned light-shielding layer, wherein the patterned light-shielding layer has an opening located directly above the light sensor unit. Attached Figure Description

[0015] The present invention can be more fully understood by reading the following detailed description of the embodiments and referring to the accompanying drawings.

[0016] Figures 1 to 6 This is a cross-sectional schematic diagram of the manufacturing process of an optical sensor module according to a certain embodiment of the present invention at various manufacturing stages.

[0017] Figures 7 to 8 This is a cross-sectional schematic diagram of the manufacturing process of an optical sensor module according to other embodiments of the present invention at various manufacturing stages;

[0018] Figure 9A This is a top view schematic diagram of an optical sensor module according to a certain embodiment of the present invention;

[0019] Figure 9B and Figure 9C for Figure 9A A magnified schematic diagram of the middle region R.

[0020] Symbol explanation:

[0021] 10: Light sensor module

[0022] 112: Substrate

[0023] 114: Etching stop layer

[0024] 114H: Thickness

[0025] 120: Light sensor unit / miniature light sensing unit

[0026] 120H: Thickness

[0027] 122: Contact

[0028] 130: Conductive column

[0029] 131: Surface

[0030] 140: Support layer

[0031] 141: Surface

[0032] 142: Surface

[0033] 150: Solder pad

[0034] 190: Opening

[0035] 20: Light sensor module

[0036] 200: Patterned light-blocking layer

[0037] 200H: Thickness

[0038] D: Diameter

[0039] R: Region Detailed Implementation

[0040] Embodiments of the invention will now be described in detail, examples of which are illustrated in the accompanying drawings. Where possible, the same reference numerals are used in the drawings and description to refer to the same or similar parts.

[0041] The following multiple embodiments are described and disclosed in detail with reference to the accompanying drawings. For clarity, many practical details will be set forth in the following description. However, it should be understood that these practical details are not intended to limit the invention. That is, in some embodiments of the invention, these practical details are not essential. Furthermore, for the sake of simplicity, some existing structures and elements will be illustrated schematically in the drawings.

[0042] In this document, the range expressed as "from one value to another" is a concise way of representing a range to avoid listing all the values ​​in that range in the specification. Therefore, the description of a particular range of values ​​covers any value within that range as well as the smaller range of values ​​defined by that value, just as if the arbitrary value and the smaller range of values ​​were explicitly stated in the specification.

[0043] This invention provides a method for manufacturing an optical sensor module. Figures 1 to 6 This is a cross-sectional schematic diagram of the manufacturing process of an optical sensor module 10 according to a certain embodiment of the present invention at various manufacturing stages. Although the method disclosed herein is described below using a series of operations or steps, the order in which these operations or steps are shown should not be construed as a limitation of the invention. For example, some operations or steps may be performed in a different order and / or simultaneously with other steps. Furthermore, it is not necessary to perform all the illustrated operations, steps, and / or features to achieve the embodiments of the present invention. In addition, each operation or step described herein may include several sub-steps or actions.

[0044] Please refer to the following first. Figure 1 An etch stop layer 114 is formed on the substrate 112. In some embodiments, the substrate 112 may be a flexible substrate, a rigid substrate, or a combination thereof, but the present invention is not limited thereto. In some embodiments, the substrate 112 may include silicon, quartz, glass, sapphire, ceramic, polyimide (PI), polycarbonate (PC), polypropylene (PP), polyethylene terephthalate (PET), other suitable materials, or combinations thereof, but the present invention is not limited thereto. In some embodiments, the substrate 112 may include a metal-glass fiber composite board or a metal-ceramic composite board, but the present invention is not limited thereto. In some embodiments, the substrate 112 may be an opaque substrate, a semi-transparent substrate, or a transparent substrate, but the present invention is not limited thereto. In some embodiments, the etch stop layer 114 is an insulating layer. More specifically, the etch stop layer 114 is a light-transmitting insulating layer. For example, the etch stop layer 114 may include silicon dioxide, silicon nitride, or other suitable materials, but the present invention is not limited thereto. In some embodiments, the thickness 114H of the etch stop layer 114 can be from 1 micrometer to 5 micrometers, for example, 2 micrometers, 3 micrometers, or 4 micrometers.

[0045] Please continue reading. Figure 1A light-receiving layer (not shown) is formed on the etch stop layer 114. The light-receiving layer includes a plurality of light sensor units 120 located on the etch stop layer 114. These light sensor units 120 may be arranged spaced apart from each other or arranged continuously. Specifically, the light-receiving surfaces of the plurality of light sensor units 120 face the etch stop layer 114. In this embodiment, the light-receiving surfaces of the plurality of light sensor units 120 are in direct contact with the etch stop layer 114. In some embodiments, the light sensor units 120 may be any element capable of converting light signals into electrical signals. In some embodiments, the light sensor units 120 may include photodiodes, phototransistors, metal-semiconductor-metal photodetectors (MSM photodetectors), or any other suitable light-sensing element, but the present invention is not limited thereto. In some embodiments, these light sensor units 120 may be arranged in an array or matrix. It is understood that each light sensor unit 120 has a plurality of contacts 122, and these contacts 122 are located on a surface opposite to the light-receiving surface. In some embodiments, these contacts 122 comprise conductive materials, such as silver (Ag), gold (Au), tin (Sn), aluminum (Al), copper (Cu), molybdenum (Mo), tungsten (W), chromium (Cr), nickel (Ni), platinum (Pt), titanium (Ti), alloys of the aforementioned metals, other suitable materials, or combinations thereof, but the invention is not limited thereto. In some embodiments, the thickness 120H of the photosensitive unit 120 can be from 1 micrometer to 10 micrometers, for example, 3 micrometers, 5 micrometers, or 7 micrometers.

[0046] In some embodiments, the microphotosensing unit 120 includes a silicon layer having an n-type region (not shown), a p-type region (not shown), and an i-type region (not shown) located between the n-type and p-type regions, wherein the n-type, i-type, and p-type regions are arranged along a horizontal direction. The n-type region comprises a highly doped n-type semiconductor material and is formed on one side of the microphotosensing unit 120. The p-type region comprises a highly doped p-type semiconductor material and is formed on the other side of the microphotosensing unit 120. The n-type and p-type regions can be formed by ion implantation or diffusion. The i-type region is located between the n-type and p-type regions, with a lower or near-intrinsic doping concentration than the n-type or p-type regions, and forms a depletion region under bias to facilitate photon absorption and the generation of electron-hole pairs. Driven by an internal or external electric field, electrons and holes move to and are collected in the n-type and p-type regions, respectively, thereby generating a photocurrent. Contact 122 can be located in a portion of the n-type and p-type regions to provide electrical connection or external bias.

[0047] Next, please refer to Figure 2Multiple conductive pillars 130 are formed on the photosensor unit 120. Specifically, these conductive pillars 130 are disposed on the contacts 122 of the photosensor unit 120 for electrical connection with the photosensor unit 120. In some embodiments, the conductive pillars 130 directly contact the contacts 122 of the photosensor unit 120. In some embodiments, the vertical projected area of ​​each conductive pillar 130 on the substrate 112 is at least greater than or equal to the vertical projected area of ​​each contact 122 on the substrate 112. In some embodiments, the conductive pillars 130 completely cover the contacts 122. In other embodiments, the conductive pillars 130 may partially cover the contacts 122. In other words, the conductive pillars 130 and the contacts 122 may be laterally offset from each other, but still need to be partially in contact to achieve electrical connection. The spacing between two adjacent conductive pillars 130 used for electrical connection with the micro photosensor unit 120 can be adjusted according to the wire layout density or heat dissipation conditions. For example, the spacing may be between 20 micrometers and 60 micrometers.

[0048] In some embodiments, the conductive post 130 may be a conductive cylinder or other conductive support structure of other geometric shapes, but the present invention is not limited thereto. In some embodiments, the material of the conductive post 130 includes gold, silver, copper, aluminum, iron, tin, nickel, alloys of the above metals, or other suitable conductive materials, but the present invention is not limited thereto.

[0049] Next, please refer to Figure 3 A support material is filled between the conductive pillars 130 to form a support layer 140. In some embodiments, the surface 142 of the support layer 140 is substantially flush with the surface 131 of the conductive pillars 130. In some embodiments, the support layer 140 is an electrically insulating layer. In some embodiments, the support layer 140 may include a light-transmitting insulating material, a semi-light-transmitting insulating material, or an opaque insulating material. In some embodiments, the thickness of the support layer 140 is between 50 micrometers and 130 micrometers or between 70 micrometers and 110 micrometers. In some embodiments, the support layer 140 may be selected from epoxy molding compound (EMC), polyimide (PI), epoxy resin, silicone, or other suitable support materials, but the invention is not limited thereto.

[0050] In some embodiments, the thickness ratio of the conductive post 130 to the micro photosensing unit 120 is between 1:5 and 1:20. In some embodiments, the conductive post 130 has an aspect ratio between 1:1 and 1:5.

[0051] Next, please refer to Figure 4Solder pads 150 can then be formed on the surface 131 of the conductive pillars 130 exposed from the support layer 140. In some embodiments, the solder pads 150 can be formed on the surface 131 of the conductive pillars 130 exposed from the support layer 140 using surface-mount technology (SMT). In other words, the solder pads 150 are in direct contact with the conductive pillars 130. In some embodiments, the material of the solder pads 150 may include gold, silver, copper, aluminum, iron, tin, nickel, alloys of the above metals, or other suitable conductive materials, but the invention is not limited thereto.

[0052] Next, please refer to Figure 5 Flip as Figure 4 The resulting semi-finished structure has the substrate 112 facing upwards.

[0053] Then, a patterned light-shielding layer 200 is formed above the light sensor unit 120, such that the light sensor unit 120 is sandwiched between the patterned light-shielding layer 200 and the support layer 140. Figure 6 As shown. It can be understood that the patterned light-shielding layer 200 is used to define the light-receiving area. Specifically, the opening 190 of the patterned light-shielding layer 200 is located directly above the light sensor unit 120, allowing light to pass through the opening 190 and be received by the light sensor unit 120. In other words, the vertical projection of the patterned light-shielding layer 200 onto the support layer 140 does not completely overlap with or only partially overlaps with the vertical projection of the light sensor unit 120 onto the support layer 140.

[0054] In one embodiment, forming the patterned light-shielding layer 200 above the light sensor unit 120 may include first thinning it. Figure 5 The substrate 112 is then etched to form an opening 190, such that the opening 190 is located directly above the photosensor unit 120, thereby forming a... Figure 6 The light sensor module 10 is shown. It can be understood that, in this way, the patterned light-shielding layer 200 is formed by... Figure 5 The substrate 112 is fabricated. That is, the patterned light-shielding layer 200 comprises the same material as the substrate 112. In this embodiment, when the patterned light-shielding layer 200 is part of the substrate 112 (e.g., comprising silicon), the thickness 200H of the patterned light-shielding layer 200 is 10 micrometers to 30 micrometers or 20 micrometers to 40 micrometers, for example, it can be 15 micrometers, 20 micrometers or 25 micrometers.

[0055] Figures 7 to 8 This is a cross-sectional schematic diagram of the manufacturing process of an optical sensor module according to other embodiments of the present invention at various manufacturing stages. Figure 7 and Figure 8 Is Figure 5The fabrication process then continues. In another embodiment, forming the patterned light-shielding layer 200 above the photosensor unit 120 may include first completely removing the substrate 112 to expose the etch stop layer 114, such as... Figure 7 As shown. Next, a patterned mask is formed on the exposed etch stop layer 114. Then, the patterned mask is etched to form a patterned light-shielding layer 200, wherein the patterned light-shielding layer 200 has an opening 190, and the opening 190 is located directly above the light sensor unit 120, thereby forming as shown. Figure 8 The light sensor module 20 is shown. In this embodiment, the material of the patterned light-shielding layer 200 may include metal, photoresist, or other suitable light-shielding materials, but the present invention is not limited thereto. For example, metal may include chromium compounds such as molybdenum (Mo), chromium (Cr), chromium oxide, and chromium nitride, nickel (Ni) and tungsten (W) alloys, titanium nitride, or other suitable metallic light-shielding materials, but the present invention is not limited thereto. Photoresist includes non-metallic light-shielding materials such as carbon black, dark metal oxides, and dark dyes.

[0056] In some embodiments, when the patterned light-shielding layer 200 is a metal, the thickness 200H of the patterned light-shielding layer 200 is 0.1 micrometers to 3 micrometers, for example, 0.5 micrometers, 1.0 micrometers, 1.5 micrometers, 2.0 micrometers, or 2.5 micrometers. In some embodiments, when the patterned light-shielding layer 200 is a photoresist, the thickness 200H of the patterned light-shielding layer 200 is 2 micrometers to 8 micrometers or 3 micrometers to 5 micrometers, for example, 3.5 micrometers, 4.0 micrometers, or 4.5 micrometers. It is understood that the better the light-shielding properties of the material of the patterned light-shielding layer 200, the smaller its thickness can be.

[0057] The above-described method for manufacturing optical sensor modules can be used to form the present invention. Figure 6 and Figure 8 The provided optical sensor modules 10 and 20. Figure 9A This is a top view of a light sensor module 10 and / or 20 according to a certain embodiment of the present invention. Figure 9B and Figure 9C for Figure 9A A magnified schematic diagram of the middle region R. Figure 9B This is a bottom view of the miniature photosensing unit 120 as seen from one side of the conductive post 130. Figure 9C This is a top view of the miniature light sensing unit 120 as seen from one side of the opening 190.

[0058] Specifically, the light sensor modules 10 and 20 include a support layer 140, one or more light sensor units 120, a plurality of conductive pillars 130, and a patterned light-shielding layer 200. The support layer 140 has opposing upper surfaces 141 and lower surfaces 142. The light sensor units 120 are disposed on the upper surface 141 of the support layer 140. The conductive pillars 130 penetrate the upper surface 141 of the support layer 140 and extend to the lower surface 142. The conductive pillars 130 are electrically connected to the light sensor units 120. The patterned light-shielding layer 200 is located above the light sensor units 120, and the patterned light-shielding layer 200 has one or more openings 190 located directly above the light sensor units 120.

[0059] In some embodiments, the light sensor modules 10 and 20 may further include an insulating layer disposed between at least one light sensor unit 120 and the patterned light-shielding layer 200, and the thickness 114H of the insulating layer is 1 micrometer to 5 micrometers. The insulating layer mentioned here is the etch stop layer 114 mentioned above. Since the insulating layer (or etch stop layer 114) comprises a light-transmitting insulating material, such as silicon dioxide or silicon nitride, it does not affect the light collection of the light sensor unit 120.

[0060] In some embodiments, the plurality of optical sensor units 120 included in the optical sensor modules 10 and 20 can be configured in an array or matrix manner, such as Figure 9A As shown. In some embodiments, the optical sensor unit 120 has a plurality of contacts 122, such as P-type contacts and N-type contacts, and each conductive post 130 directly contacts each contact 122 to achieve electrical connection, such as... Figure 9B As shown. In some embodiments, the width or diameter D of each light sensor unit 120 is between 10 micrometers and 80 micrometers or between 40 micrometers and 60 micrometers, for example, 42 micrometers, 44 micrometers, 46 micrometers, 48 ​​micrometers, 50 micrometers, 52 micrometers, 54 micrometers, 56 micrometers, or 58 micrometers. However, the shape of the light sensor unit 120 is not limited to... Figure 9A , Figure 9B and Figure 9C As shown, other shapes are within the scope of this invention.

[0061] In some embodiments, a plurality of miniature photosensitive units 120 may be arranged spaced apart from each other or arranged continuously. When the plurality of miniature photosensitive units 120 are arranged continuously, they may be formed in the same layer, such as a silicon layer. By locally forming an n-type region (not shown), a p-type region (not shown), and an i-type region (not shown) in the silicon layer, and forming contacts 122 at the positions corresponding to the n-type and p-type regions, electrons and holes of the miniature photosensitive unit 120 may migrate toward the n-type and p-type regions respectively when receiving light signals, thereby generating a photocurrent for detection. The contacts 122 electrically connected to the n-type and p-type regions respectively may be complementary metal wires, which are conducted to an external circuit through conductive posts 130.

[0062] In some embodiments, the patterned light-shielding layer 200 comprises silicon, metal, or photoresist. In some embodiments, when the patterned light-shielding layer 200 is silicon, the thickness 200H of the patterned light-shielding layer 200 is 10 micrometers to 30 micrometers or 20 micrometers to 40 micrometers. In some embodiments, when the patterned light-shielding layer 200 is metal, the thickness 200H of the patterned light-shielding layer 200 is 0.1 micrometers to 3 micrometers. In some embodiments, when the patterned light-shielding layer 200 is photoresist, the thickness 200H of the patterned light-shielding layer 200 is 2 micrometers to 8 micrometers or 3 micrometers to 5 micrometers. The formation methods, materials, and related feature details of each element have been described in detail above and will not be repeated here.

[0063] In summary, the optical sensor module and its manufacturing method provided by this invention utilize a support layer and multiple conductive pillars disposed therein to replace the traditional native substrate, thereby achieving miniaturization of the optical sensor module to meet the needs of practical applications. Furthermore, the method for manufacturing the optical sensor module of this invention can reduce the tolerances of various manufacturing processes, thereby improving overall accuracy and further enhancing the performance of the optical sensor module. In addition, the design of the optical sensor module provided by this invention allows for electrical independence of each optical sensor unit.

[0064] Although the invention has been described in considerable detail with reference to certain embodiments, other embodiments are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the embodiments contained herein.

[0065] It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the invention without departing from its scope or spirit. In view of the foregoing, this invention is intended to cover modifications and variations falling within the appended claims.

Claims

1. A light sensor module, comprising: The support layer has opposing upper and lower surfaces; A light sensor unit is disposed on the upper surface of the support layer; Multiple conductive pillars penetrate the support layer and are electrically connected to the optical sensor unit; as well as A patterned light-shielding layer is located above the light sensor unit, wherein the patterned light-shielding layer has an opening located directly above the light sensor unit.

2. The optical sensor module as claimed in claim 1 further includes an insulating layer disposed between the optical sensor unit and the patterned light-shielding layer.

3. The optical sensor module as claimed in claim 1, wherein the optical sensor unit has multiple contacts, and the multiple conductive posts are in direct contact with the multiple contacts.

4. The optical sensor module of claim 1, wherein the patterned light-shielding layer comprises silicon, metal or photoresist.

5. A method for manufacturing an optical sensor module, comprising: An etch stop layer is formed on the substrate; A photosensitive unit is formed on the etch stop layer; Multiple conductive pillars are formed on the optical sensor unit; A support layer is formed between the plurality of conductive pillars; as well as A patterned light-shielding layer is formed on the light sensor unit.

6. The method for manufacturing a light sensor module as claimed in claim 5, wherein the step of forming the patterned light-shielding layer includes: Thin the substrate; as well as The substrate is etched to form an opening such that the opening is located directly above the photosensitive unit.

7. The method for manufacturing a light sensor module as claimed in claim 5, wherein the step of forming the patterned light-shielding layer includes: Remove the substrate to expose the etch stop layer; A patterned mask is formed on the etch stop layer; as well as The patterned mask is etched to form the patterned light-shielding layer, wherein the patterned light-shielding layer has an opening located directly above the light sensor unit.

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