Optical element and wafer level packaging method of optical element

Abstract

The invention provides an optical element and a wafer-level packaging method of the optical element, the packaging method plays a bearing role by using a bearing wafer or a recombined wafer, and in the packaging process, the steps from wafer cutting to shading protection material removal are all carried out in a wafer-level operation mode, so that the packaging efficiency can be remarkably improved, and the packaging cost is reduced. And in addition, the wafer-level packaging is adopted on the whole, so that the consistency of products can be improved.

Description

Technical Field

[0001] The present invention relates to the field of optoelectronic device packaging, and in particular to an optical element and a wafer-level packaging method for the optical element. Background Art

[0002] For optical component units, the current wafer-level module packaging in the industry is to bond the optical wafer to the packaged sensor wafer, spray the periphery for light shielding after cutting, or place it in a mold for light shielding protection after cutting, which is not actually a complete wafer-level module packaging. Therefore, the current packaging process still has a lot of room for improvement in production efficiency and production yield. Summary of the invention

[0003] The object of the present invention is to provide an optical element and a wafer-level packaging method for the optical element, so as to realize the full-process wafer-level packaging of the optical element.

[0004] The present invention provides a wafer-level packaging method for an optical element, comprising the steps of:

[0005] Providing a first wafer, wherein the first wafer has a first surface and a second surface opposite to each other, and a plurality of regularly arranged optical functional structures are formed on the first surface of the first wafer;

[0006] Placing the first wafer on a temporary carrier wafer, with the second surface of the first wafer facing the temporary carrier wafer;

[0007] dividing the first wafer into a plurality of optical element units, each of the optical element units comprising at least one optical functional structure;

[0008] Debond the temporary carrier wafer to obtain a single optical element unit.

[0009] As a further improvement of the present invention, before bonding the second surface of the first wafer to a temporary carrier wafer, the step of:

[0010] A second wafer is provided, and the second wafer is bonded to the first surface of the first wafer.

[0011] As a further improvement of the present invention, dividing the first wafer into a plurality of optical element units specifically includes:

[0012] The second wafer and the first wafer are divided into a plurality of the optical element units by mechanical cutting or chemical etching, and each of the optical element units includes at least one optical functional structure.

[0013] As a further improvement of the present invention, before bonding the second surface of the first wafer to a temporary carrier wafer, the step of:

[0014] The packaged sensor wafer-level substrate is bonded to the second surface of the first wafer, the sensor wafer-level substrate includes a plurality of regularly arranged sensors, and after bonding, the sensors are arranged corresponding to the optical functional structure.

[0015] As a further improvement of the present invention, placing the first wafer on a temporary carrier wafer specifically includes:

[0016] The sensor wafer-level substrate is bonded to the temporary carrier wafer, so that the first wafer and the sensor wafer-level substrate are placed on the temporary carrier wafer.

[0017] As a further improvement of the present invention, dividing the first wafer into a plurality of optical element units specifically includes:

[0018] The first wafer and the sensor wafer-level substrate are divided into a plurality of the optical element units by mechanical cutting or chemical etching, and each of the optical element units includes at least one optical functional structure and one sensor.

[0019] As a further improvement of the present invention, before debonding the temporary carrier wafer, the present invention further includes the following steps:

[0020] Covering the surface of the optical element unit with a light-shielding protective material;

[0021] Removing the light-shielding protective material from a portion of the surface area of ​​the optical element unit to form a light-transmitting area through which at least a portion of the optical functional structure is transmitted, and separating adjacent optical element units;

[0022] As a further improvement of the present invention, the surface of the optical element unit is covered with a light-shielding protective material, specifically comprising:

[0023] The light-shielding protective material is covered on the surface of the optical element unit by spin coating and chemical vapor deposition to form a protective layer covering the surface of the optical element unit and filling the area between the surfaces of the optical element units.

[0024] As a further improvement of the present invention, the light-shielding protective material of a part of the surface area of ​​the optical element unit is removed to form a light-transmitting area through which at least a part of the optical functional structure is transmitted, and adjacent optical element units are separated, specifically comprising:

[0025] Removing the light-shielding protective material from a portion of the surface area of ​​the optical element unit by dry etching to form the light-transmitting area through which at least a portion of the optical functional structure is transmitted;

[0026] The light-shielding protection material between adjacent optical element units is removed by etching or cutting, so that adjacent optical element units are separated.

[0027] As a further improvement of the present invention, the light-shielding protective material is covered on the surface of the optical element unit, specifically comprising:

[0028] The light-shielding protective material is covered on the surface of the optical element unit by atomic layer deposition, so as to form a protective layer covering the surface of the optical element unit and the surface of the temporary supporting wafer.

[0029] As a further improvement of the present invention, the light-shielding protective material is removed from a portion of the surface area of ​​the optical element unit to form a light-transmitting area through which at least a portion of the optical functional structure is transmitted, and adjacent optical element units are separated, specifically comprising:

[0030] The light-shielding protective material of a part of the surface area of ​​the optical element unit is removed by dry etching to form a light-transmitting area through which at least a part of the optical functional structure is transmitted.

[0031] As a further improvement of the present invention, a plurality of regularly arranged optical functional structures are formed on the first surface of the first wafer, specifically including:

[0032] A plurality of regularly arranged metasurface optical elements are formed on the first surface of the first wafer, and a nanoscale microstructure unit array is formed on the surface of the metasurface optical element.

[0033] The present invention also provides a wafer-level packaging method for an optical element, comprising the steps of:

[0034] Providing a first wafer, wherein the first wafer has a first surface and a second surface opposite to each other, and a plurality of regularly arranged optical functional structures are formed on the first surface of the first wafer;

[0035] Placing the first wafer on a reconstructed wafer, with the second surface of the first wafer facing the reconstructed wafer, the reconstructed wafer comprising a plurality of regularly arranged redistribution areas, the redistribution areas being arranged corresponding to the optical functional structures;

[0036] dividing the first wafer into a plurality of optical element units, each of the optical element units comprising at least one optical functional structure;

[0037] Removing the bonding layer on the surface of the reconstructed wafer to expose the electrical connection area on the surface of the reconstructed wafer;

[0038] The wafer is cut and reconstructed to obtain a single optical element unit.

[0039] As a further improvement of the present invention, before removing the bonding layer on the surface of the reconstructed wafer, the method further includes the following steps:

[0040] Providing a second wafer, and bonding the second wafer to the first surface of the first wafer;

[0041] The first wafer and the second wafer are divided into a plurality of optical element units, each of which includes at least one optical functional structure.

[0042] As a further improvement of the present invention, bonding the second wafer to the first surface of the first wafer specifically includes:

[0043] directly bonding the second wafer to the first surface of the wafer via a bonding material; or

[0044] A support pad is added between the first wafer and the second wafer, and the second wafer is bonded to the first surface of the wafer by means of the support pad through a bonding material.

[0045] As a further improvement of the present invention, the bonding material is Sio2, SIN, Al2O3, Si, or a thin film adhesive, or epoxy resin.

[0046] As a further improvement of the present invention, before the cutting and reconstructing of the wafer, the following steps are further included:

[0047] Covering the surface of the optical element unit with a light-shielding protective material;

[0048] The light-shielding protective material on the surface of the recombinant chip and part of the surface area of ​​the optical element unit is removed to form a light-transmitting area through which at least part of the optical functional structure is transmitted.

[0049] As a further improvement of the present invention, a plurality of regularly arranged optical functional structures are formed on the first surface of the first wafer, specifically including:

[0050] A plurality of regularly arranged metasurface optical elements are formed on the first surface of the first wafer, and a nanoscale microstructure unit array is formed on the surface of the metasurface optical element.

[0051] An optical element manufactured by the above-mentioned wafer-level packaging method for an optical element, the optical element comprising a reconstructed wafer substrate, the surface of the reconstructed wafer substrate being provided with a redistribution area and an electrical connection area electrically connected to each other;

[0052] A first optical structure is disposed on the reconstructed wafer substrate, an optical functional structure is disposed on a surface of the first optical structure opposite to the reconstructed wafer substrate, and the first optical structure exposes the electrical connection area.

[0053] As a further improvement of the present invention, a second optical structure component is further arranged on the first optical structure component, and the outer surfaces of the first optical structure component and the second optical structure component are covered with a light-shielding protective material, and the light-shielding protective material at least exposes a portion of the optical functional structure.

[0054] The beneficial effects of the present invention are as follows: the present invention uses a carrying substrate or a reconstructed wafer to play the role of a carrying wafer. During the packaging process, the steps from wafer cutting to removing the light-shielding protective material are all performed through wafer-level operations, which can significantly improve the packaging efficiency and reduce the packaging cost. The overall use of wafer-level packaging can improve product consistency. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 It is a schematic diagram of the steps of the wafer-level packaging method of the optical element in Example 1 of the present invention.

[0056] Figures 2 to 8 It is a schematic flow chart of each step of the wafer-level packaging method of the optical element in Example 1 of the present invention.

[0057] Fig. 9 It is a schematic diagram of the wafer bonding step process in Example 2 of the present invention.

[0058] Fig.10 It is a schematic diagram of the optical element unit in Example 2 of the present invention.

[0059] Fig.11 It is a schematic flow chart of the step of covering the light-shielding protective material in Example 3 of the present invention.

[0060] Fig.12 It is a schematic flow chart of the step of removing the light-shielding protective material in Example 3 of the present invention.

[0061] Fig.13 It is a schematic diagram of the steps of the wafer-level packaging method of the optical element in Example 4 of the present invention.

[0062] Figures 14 to 21 It is a schematic flow chart of each step of the wafer-level packaging method for optical elements in Example 4 of the present invention.

[0063] Fig. 22 It is a schematic diagram of the steps of the wafer-level packaging method of the optical element in Example 5 of the present invention.

[0064] Figure 23 to Figure 27 It is a schematic flow chart of each step of the wafer-level packaging method for optical elements in Example 5 of the present invention.

[0065] Fig.28 It is a schematic diagram of the steps of the wafer-level packaging method of the optical element in Example 6 of the present invention.

[0066] Fig.29 It is a schematic diagram of the optical element unit in Example 6 of the present invention. DETAILED DESCRIPTION

[0067] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in combination with the specific implementation methods of the present invention and the corresponding drawings. Obviously, the described implementation methods are only part of the implementation methods of the present invention, not all implementation methods. Based on the implementation methods of the present invention, all other implementation methods obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0068] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0069] This embodiment provides a wafer-level packaging method for an optical element. The packaging method provided by this embodiment uses a carrier substrate or a reconstructed wafer to play the role of a carrier wafer. During the packaging process, the steps from wafer cutting to removing the light-shielding protective material are all performed by wafer-level operations, which can significantly improve packaging efficiency and reduce packaging costs. Moreover, the overall use of wafer-level packaging can improve product consistency. The wafer-level packaging method for an optical element provided by this embodiment is described below with respect to multiple embodiments.

[0070] Example 1

[0071] like Figure 1 As shown, Embodiment 1 provides a wafer-level packaging method for an optical element unit 5, which comprises the steps of:

[0072] S11: Figure 2 As shown, a first wafer 1 is provided. The first wafer 1 has a first surface 1 a and a second surface 1 b opposite to each other. A plurality of regularly arranged optical functional structures 11 are formed on the first surface 1 a of the first wafer.

[0073] S12: Figure 3 As shown, a second wafer 2 is provided, and the second wafer 2 is bonded to the first surface 1 a of the first wafer.

[0074] S13: Figure 4 As shown, the first wafer 1 is placed on a temporary carrier wafer 4 , and the second surface 1 b of the first wafer is arranged toward the temporary carrier wafer 4 .

[0075] S14: Figure 5 As shown, the second wafer 2 and the first wafer 1 are divided into a plurality of optical element units 5 , and each optical element unit 5 includes at least one optical functional structure 11 .

[0076] S15: Figure 6As shown, the surface of the optical element unit 5 is covered with a light shielding protective material 6 .

[0077] S16: Figure 7 As shown, the light-shielding protective material 6 on a portion of the surface area of ​​the optical element unit 5 is removed to form a light-transmitting area 51 through which at least a portion of the optical functional structure 11 is transmitted, and adjacent optical element units 5 are separated.

[0078] S17: Figure 8 As shown, the temporary carrier wafer 4 is debonded to obtain a single optical element unit 5.

[0079] In step S11, the wafer used is a wafer suitable for optical devices, such as a transparent material such as a glass substrate. The optical functional structures 11 are arranged in an array at regular intervals on the first surface 1a of the wafer, and a cutting path is formed between adjacent optical functional structures 11. In subsequent steps, the wafer can be divided along the cutting path to obtain a single chip. It should be noted that the cutting path is only a blank area reserved for cutting between adjacent optical functional structures 11, and there is no actual boundary line between the cutting channel and the optical functional structures 11 on both sides.

[0080] The optical functional structure 11 can be an optical element such as a metasurface, a silicon lens, etc. In Example 1, the optical functional structure 11 is a metasurface, which is a programmable planar medium with an artificially designed subwavelength structure, and a nanoscale microstructure unit is formed on its surface. The microstructure unit can be designed to have a precise size, shape and arrangement, thereby achieving highly customized control of light and playing a role in effectively encoding the intensity and phase distribution of light.

[0081] In step S12, according to different application requirements and design purposes, the second wafer 2 can be similar to the first wafer 1 and also be provided with an optical functional structure, or can also be provided as a transparent wafer-level substrate to protect and transmit light to the optical functional structure 11 in the first wafer 1.

[0082] In other embodiments, when the application precision requirement is low, the second wafer 2 may be omitted and only the first wafer 1 is provided. In subsequent steps, the first wafer 1 is directly bonded to the temporary carrier wafer 4, and the first wafer 1 is directly coated and the protective layer is removed. The method steps of only providing the first wafer 1 are similar to the relevant steps of Example 1, and those skilled in the art may refer to Example 1 for implementation.

[0083] In other embodiments, a multi-layer stacking structure can also be formed based on the second wafer 2 according to design requirements. When setting up multi-layer wafers, only the wafer bonding step needs to be added. The subsequent steps are similar to those in Example 1 and will not be repeated here.

[0084] Furthermore, the first wafer 1 and the second wafer 2 can be bonded by solid materials such as SiO2, SiN, TiO2, Al2O3, Si, thin film adhesive, or epoxy resin, or can be bonded by a support pad 3 between the first wafer 1 and the second wafer 2. In Example 1, a support pad 3 is provided between the first wafer 1 and the second wafer 2, and the support pad 3 is located in the blank area between the super surfaces. A sealed cavity for accommodating the super surface is formed by the upper surface of the first wafer 1, the lower surface between the second wafer 2, and the side wall of the support pad 3, and an air gap is formed in the sealed cavity.

[0085] In step S13, the second surface 1b of the first wafer is placed toward the temporary carrier wafer 4 and bonded to the temporary carrier wafer 4. By first placing the first wafer 1 on the temporary carrier wafer 4 and then performing the subsequent packaging steps, the divided single optical element unit 5 can be effectively fixed to stabilize its position.

[0086] There is no specific limitation on the material of the temporary carrier wafer 4 as long as it can provide structural support.

[0087] In step S14, it specifically includes:

[0088] Along the cutting lines on the surface of the second wafer 2 , the second wafer 2 and the first wafer 1 are divided into a plurality of optical element units 5 by mechanical cutting or chemical etching. Each optical element unit 5 includes at least one optical functional structure 11 .

[0089] After the first wafer 1 and the second wafer 2 are divided along the cutting path to form a single optical element unit 5, the temporary support wafer 4 is used to fix and support the separated optical element unit 5. The support pad 3 disposed between the first wafer 1 and the second wafer 2 is removed from a portion of the middle area to form a sealing structure around the optical functional structure 11.

[0090] In the first embodiment, each optical element unit 5 includes one optical functional structure 11 . In other embodiments, the number of optical functional structures 11 in each optical element unit 5 may be adjusted according to design requirements.

[0091] In step S15 and step S16, it specifically includes:

[0092] The light shielding protective material 6 is covered on the surface of the optical element unit 5 by spin coating and chemical vapor deposition to form a protective layer covering the surface of the optical element unit 5 and filling the area between the surfaces of the optical element unit 5;

[0093] The light shielding protective material 6 of a part of the surface area of ​​the optical element unit 5 is removed by dry etching to form a light-transmitting area 51 through which at least a part of the optical functional structure 11 is transmitted;

[0094] The light shielding protective material 6 between adjacent optical element units 5 is removed by etching or cutting, so that the adjacent optical element units 5 are separated.

[0095] The light-shielding protective material 6 can be an opaque material such as metal, metal compound, organic matter, etc., to shield and protect the optical functional structure 11. In Example 1, the light-shielding layer is formed by spin coating and chemical vapor deposition technology, which can achieve better film uniformity and deposition control, but it will deposit a thicker film in a relatively short time, so the light-shielding protective material 6 deposited in the area between the optical element units 5 is cut twice.

[0096] After completing the above steps, the temporary carrier wafer 4 is debonded to obtain a single packaged optical element unit 5. The entire packaging process is carried out on the temporary carrier wafer 4, which can effectively improve the packaging efficiency and reduce the packaging cost. The overall wafer-level packaging can improve the consistency of the product.

[0097] When the precision requirement for the optical element is relatively low, in other embodiments of the present invention, the step of providing the light-shielding protective material 6 on the surface of the optical element may be omitted.

[0098] Example 2

[0099] Embodiment 2 provides a wafer-level packaging method for an optical element unit 5, and the method steps are substantially similar to those of Embodiment 1, except that:

[0100] In step S12, Fig. 9 As shown, the first wafer 1 and the second wafer 2 are directly bonded, and the second wafer 2 is entirely covered on the metasurface to provide protection and light transmission for the metasurface.

[0101] The remaining steps are similar to those in Example 1 and will not be described in detail herein. Fig.10 As shown, the single optical element unit 5 finally obtained is shown.

[0102] Example 3

[0103] Embodiment 3 provides a wafer-level packaging method for an optical element unit 5, and the method steps are substantially similar to those of Embodiment 2, except that:

[0104] like Fig.11 and Fig.12 As shown, in step S15 and step S16, it specifically includes:

[0105] The light shielding protective material 6 is covered on the surface of the optical element unit 5 by atomic layer deposition, so as to form a protective layer covering the surface of the optical element unit 5 and the surface of the temporary supporting wafer 4 .

[0106] The light-shielding protective material 6 on a part of the surface area of ​​the optical element unit 5 is removed by dry etching to form a light-transmitting area 51 through which at least a part of the optical functional structure 11 is transmitted.

[0107] In Example 3, the atomic layer deposition method is used instead of the chemical vapor deposition in Example 1. The atomic layer deposition can well control the thickness of the growing light-shielding layer and regulate it at the nanometer and sub-nanometer levels. Therefore, after the light-shielding layer is formed by atomic layer deposition, the light-shielding protection material 6 will not form a connecting area between the optical element units 5, and there is no need for secondary cutting.

[0108] Example 4

[0109] like Fig.13 As shown, embodiment 4 provides a wafer-level packaging method for an optical element unit 5, which comprises the steps of:

[0110] S41: Fig.14 As shown, a first wafer 1 is provided. The first wafer 1 has a first surface 1 a and a second surface 1 b opposite to each other. A plurality of regularly arranged optical functional structures 11 are formed on the first surface 1 a of the first wafer.

[0111] S42: Fig.15 As shown, a second wafer 2 is provided, and the second wafer 2 is bonded to the first surface 1 a of the first wafer.

[0112] S43: Fig.16 As shown, the packaged sensor wafer-level substrate 8 is bonded to the second surface 1 b of the first wafer. The sensor wafer-level substrate 8 includes a plurality of regularly arranged sensors 81 . After bonding, the sensors 81 are arranged corresponding to the optical functional structure 11 .

[0113] S44: Fig.17 As shown, the sensor wafer-level substrate 8 is bonded to the temporary carrier wafer 4 , so that the second wafer 2 , the first wafer 1 and the sensor wafer-level substrate 8 are placed on the temporary carrier wafer 4 .

[0114] S45: Fig.18 As shown, the second wafer 2 , the first wafer 1 and the sensor wafer-level substrate 8 are divided into a plurality of optical element units 5 , and each optical element unit 5 includes at least one optical functional structure 11 and a sensor 81 .

[0115] S46: Fig.19 As shown, the surface of the optical element unit 5 is covered with a light shielding protective material 6 .

[0116] S47: Fig. 20As shown, the light-shielding protective material 6 on a portion of the surface area of ​​the optical element unit 5 is removed to form a light-transmitting area 51 through which at least a portion of the optical functional structure 11 is transmitted, and adjacent optical element units 5 are separated.

[0117] S48: Fig.21 As shown, the temporary carrier wafer 4 is debonded to obtain a single optical element unit 5.

[0118] In Example 4, the difference from Example 2 is that in step S43 and step S44, the wafer-level substrate 8 of the packaged sensor is bonded to the second side 1b of the first wafer 1. The wafer-level substrate mentioned here refers to the sensor 81 that has been uniformly packaged in a substrate of wafer-level size. After bonding with the first wafer 1, the wafer-level packaging process can be directly carried out, thereby improving the packaging efficiency and realizing the full-process wafer-level packaging of the optical element unit module including the sensor.

[0119] In Embodiment 4, each optical element unit 5 includes an optical functional structure 11 and a sensor 81 corresponding thereto. The sensor 81 is disposed relative to the optical functional structure 11 to receive light regulated by the optical functional structure 11 .

[0120] It should be noted that step S43 and step S42 can be adjusted according to production needs and the design of the optical element unit 5, and there is no specific order of precedence.

[0121] In step S46 and step S47, similar to the above-mentioned embodiment, the light shielding protection layer can also be formed by chemical vapor deposition and atomic layer deposition methods, which will not be described in detail here.

[0122] In other embodiments, when the application accuracy requirement is low, the second wafer 2 can also be omitted, and only the first wafer 1 and the wafer-level substrate 8 of the sensor can be set, or a multi-layer stacking structure can be formed based on the second wafer 2. The steps are similar to those in Example 4 and will not be repeated here.

[0123] Example 5

[0124] like Fig. 22 As shown, embodiment 5 provides a wafer-level packaging method for an optical element unit 5, which comprises the steps of:

[0125] S51: Fig.23 As shown, a first wafer 1 is provided. The first wafer 1 has a first surface 1 a and a second surface 1 b opposite to each other. A plurality of regularly arranged optical functional structures 11 are formed on the first surface 1 a of the first wafer.

[0126] S52: Fig.24As shown, the first wafer 1 is placed on a reconstituted wafer 7 , and the second surface 1 b of the first wafer is arranged toward the reconstituted wafer 7 . The reconstituted wafer 7 includes a plurality of regularly arranged redistribution areas, and the redistribution areas are arranged corresponding to the optical functional structures 11 .

[0127] S53: Fig.25 As shown, the first wafer 1 is divided into a plurality of optical element units 5 , and each optical element unit 5 includes at least one optical functional structure 11 .

[0128] S54: Fig.26 As shown, the bonding layer on the surface of the reconstructed wafer 7 is removed to expose the electrical connection area on the surface of the reconstructed wafer 7 .

[0129] S55: Fig. 27 As shown, the reconstructed wafer 7 is cut to obtain a single optical element unit 5 .

[0130] Compared with Embodiments 1 to 4, in Embodiment 5, a reconstructed wafer 7 is directly used to replace the temporary carrier wafer 4, and the reconstructed wafer 7 is used to play a temporary carrier role. When the first wafer 1 is cut, the packaged reconstructed wafer 7 is not cut first. After the wafer cutting is completed, the bonding layer on the surface of the reconstructed wafer 7 is first removed to expose the electrical connection area on the surface of the reconstructed wafer 7, and then the reconstructed wafer 7 is cut to obtain the final single optical element unit 5.

[0131] The bonding layer on the surface of the reconstituted wafer 7 is the bonding material remaining after bonding with the first wafer 1 .

[0132] In Example 5, only the first wafer 1 is used for packaging, and its surface is no longer covered with a light-shielding protective layer. It can be applied to optical devices such as laser diodes, photodiodes, lighting components, and transmitting components.

[0133] Example 6

[0134] like Fig.28 As shown, Embodiment 6 provides a wafer-level packaging method for an optical element unit 5, which comprises the steps of:

[0135] S61: providing a first wafer 1, wherein the first wafer 1 has a first surface 1a and a second surface 1b opposite to each other, and a plurality of regularly arranged optical functional structures 11 are formed on the first surface 1a of the first wafer.

[0136] S62: Provide a second wafer 2, and bond the second wafer 2 to the first surface 1a of the first wafer.

[0137] S63 : placing the first wafer 1 on a reconstructed wafer 7 , with the second surface 1 b of the first wafer facing the reconstructed wafer 7 . The reconstructed wafer 7 includes a plurality of regularly arranged redistribution areas, and the redistribution areas are arranged corresponding to the optical functional structures 11 .

[0138] S64 : dividing the first wafer 1 and the second wafer 2 into a plurality of optical element units 5 , each of the optical element units 5 including at least one optical functional structure 11 .

[0139] S65: removing the bonding layer on the surface of the reconstructed wafer 7 to expose the electrical connection area on the surface of the reconstructed wafer 7 .

[0140] S66: Cover the surface of the optical element unit 5 with a light-shielding protective material 6 .

[0141] S67: removing the light-shielding protective material 6 on the surface of the recombinant chip and a part of the surface area of ​​the optical element unit 5 to form a light-transmitting area 51 through which at least a part of the optical functional structure 11 is visible.

[0142] S68: Cutting the reconstructed wafer 7 to obtain single optical element units 5.

[0143] In Example 6, Example 5 is combined with Examples 1 to 4, and a reconstructed wafer 7 is used to temporarily support the wafer 4. Fig.29 As shown, an optical chip module including a multi-layer structure and a circuit layer is finally formed, which can be applied to optical devices such as a contact image sensor 81.

[0144] Example 7

[0145] like Fig.29 As shown, Example 7 is an optical element unit manufactured by the method provided by Example 6.

[0146] The optical element unit 5 includes a reconstructed wafer substrate 7a, and a reconstructed wafer substrate 7a has a surface provided with a redistribution area 7a1 and an electrical connection area 7a2 electrically connected to each other;

[0147] A first optical structure member 1 a is disposed on the reconstructed wafer substrate. An optical functional structure is disposed on a surface of the first optical structure member 1 a that is away from the reconstructed wafer substrate. The first optical structure member 1 a exposes an electrical connection area 7 a 1 .

[0148] A second optical structure 2a is also disposed on the first optical structure 1a. The outer surfaces of the first optical structure 1a and the second optical structure 2a are covered with a light-shielding protective material 6, and the light-shielding protective material at least exposes a portion of the optical functional structure.

[0149] To sum up, this embodiment uses a carrying substrate or a reconstructed wafer to carry the wafer. During the packaging process, all steps from wafer cutting to removal of light-shielding protective materials are performed through wafer-level operations, which can significantly improve packaging efficiency and reduce packaging costs. The overall use of wafer-level packaging can improve product consistency.

[0150] It should be understood that although this specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each implementation mode may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0151] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the present invention and are not intended to limit the scope of protection of the present invention. All equivalent implementation methods or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A wafer-level packaging method for an optical element, characterized in that: Includes steps: Providing a first wafer, wherein the first wafer has a first surface and a second surface opposite to each other, and a plurality of regularly arranged optical functional structures are formed on the first surface of the first wafer; Placing the first wafer on a temporary carrier wafer, with the second surface of the first wafer facing the temporary carrier wafer; dividing the first wafer into a plurality of optical element units, each of the optical element units comprising at least one optical functional structure; Debond the temporary carrier wafer to obtain a single optical element unit.

2. The wafer-level packaging method for optical elements according to claim 1, characterized in that: Before bonding the second surface of the first wafer to a temporary carrier wafer, the method further includes the following steps: A second wafer is provided, and the second wafer is bonded to the first surface of the first wafer.

3. The wafer-level packaging method of an optical element according to claim 2, characterized in that: Dividing the first wafer into a plurality of optical element units specifically includes: The second wafer and the first wafer are divided into a plurality of the optical element units by mechanical cutting or chemical etching, and each of the optical element units includes at least one optical functional structure.

4. The wafer-level packaging method of an optical element according to claim 2, characterized in that: The step of bonding the second wafer to the first surface of the first wafer specifically includes: directly bonding the second wafer to the first surface of the wafer via a bonding material; or A support pad is added between the first wafer and the second wafer, and the second wafer is bonded to the first surface of the wafer by means of the support pad through a bonding material.

5. The wafer-level packaging method for optical elements according to claim 4, characterized in that: The bonding material is Sio2, SIN, Al2O3, Si, or a thin film adhesive, or epoxy resin.

6. The wafer-level packaging method for optical elements according to claim 1 or 2, characterized in that: Before bonding the second surface of the first wafer to a temporary carrier wafer, the method further includes the following steps: The packaged sensor wafer-level substrate is bonded to the second surface of the first wafer, the sensor wafer-level substrate includes a plurality of regularly arranged sensors, and after bonding, the sensors are arranged corresponding to the optical functional structure.

7. The wafer-level packaging method for optical elements according to claim 4, characterized in that: Placing the first wafer on a temporary carrier wafer specifically includes: The sensor wafer-level substrate is bonded to the temporary carrier wafer, so that the first wafer and the sensor wafer-level substrate are placed on the temporary carrier wafer.

8. The wafer-level packaging method for optical elements according to claim 5, characterized in that: The dividing the first wafer into a plurality of optical element units specifically includes: The first wafer and the sensor wafer-level substrate are divided into a plurality of the optical element units by mechanical cutting or chemical etching, and each of the optical element units includes at least one optical functional structure and one sensor.

9. The wafer-level packaging method for optical elements according to claim 1, characterized in that: Before debonding the temporary carrier wafer, the method further includes the following steps: Covering the surface of the optical element unit with a light-shielding protective material; The light-shielding protective material on a portion of the surface area of ​​the optical element unit is removed to form a light-transmitting area through which at least a portion of the optical functional structure is transmitted, and adjacent optical element units are separated.

10. The wafer-level packaging method for optical elements according to claim 9, characterized in that: Covering the surface of the optical element unit with a light-shielding protective material specifically comprises: The light-shielding protective material is covered on the surface of the optical element unit by spin coating and chemical vapor deposition to form a protective layer covering the surface of the optical element unit and filling the area between the surfaces of the optical element units.

11. The wafer-level packaging method for optical elements according to claim 10, characterized in that: Removing the light-shielding protective material from a portion of the surface area of ​​the optical element unit to form a light-transmitting area through which at least a portion of the optical functional structure is transmitted, and separating adjacent optical element units, specifically includes: Removing the light-shielding protective material from a portion of the surface area of ​​the optical element unit by dry etching to form the light-transmitting area through which at least a portion of the optical functional structure is transmitted; The light-shielding protection material between adjacent optical element units is removed by etching or cutting, so that adjacent optical element units are separated.

12. The wafer-level packaging method of an optical element according to claim 9, characterized in that: The step of covering the surface of the optical element unit with a light-shielding protective material specifically comprises: The light-shielding protective material is covered on the surface of the optical element unit by atomic layer deposition, so as to form a protective layer covering the surface of the optical element unit and the surface of the temporary supporting wafer.

13. The wafer-level packaging method of an optical element according to claim 12, characterized in that: Removing the light-shielding protective material from a portion of the surface area of ​​the optical element unit to form a light-transmitting area through which at least a portion of the optical functional structure is transmitted, and separating adjacent optical element units, specifically includes: The light-shielding protective material of a part of the surface area of ​​the optical element unit is removed by dry etching to form a light-transmitting area through which at least a part of the optical functional structure is transmitted.

14. The wafer-level packaging method for optical elements according to claim 1, characterized in that: The first surface of the first wafer is formed with a plurality of regularly arranged optical functional structures, specifically including: A plurality of regularly arranged metasurface optical elements are formed on the first surface of the first wafer, and a nanoscale microstructure unit array is formed on the surface of the metasurface optical element.

15. A wafer-level packaging method for an optical element, characterized in that: Includes steps: Providing a first wafer, wherein the first wafer has a first surface and a second surface opposite to each other, and a plurality of regularly arranged optical functional structures are formed on the first surface of the first wafer; Placing the first wafer on a reconstructed wafer, with the second surface of the first wafer facing the reconstructed wafer, the reconstructed wafer comprising a plurality of regularly arranged redistribution areas, the redistribution areas being arranged corresponding to the optical functional structures; dividing the first wafer into a plurality of optical element units, each of the optical element units comprising at least one optical functional structure; Removing the bonding layer on the surface of the reconstructed wafer to expose the electrical connection area on the surface of the reconstructed wafer; The wafer is cut and reconstructed to obtain a single optical element unit.

16. The wafer-level packaging method for optical elements according to claim 15, characterized in that: Before removing the bonding layer on the surface of the reconstructed wafer, the method further comprises the following steps: Providing a second wafer, and bonding the second wafer to the first surface of the first wafer; The first wafer and the second wafer are divided into a plurality of optical element units, each of which includes at least one optical functional structure.

17. The wafer-level packaging method for optical elements according to claim 16, characterized in that: Before the wafer is cut and reconstructed, the following steps are also included: Covering the surface of the optical element unit with a light-shielding protective material; The light-shielding protective material on the surface of the recombinant chip and part of the surface area of ​​the optical element unit is removed to form a light-transmitting area through which at least part of the optical functional structure is transmitted.

18. The wafer-level packaging method for optical elements according to claim 15, characterized in that: The first surface of the first wafer is formed with a plurality of regularly arranged optical functional structures, specifically including: A plurality of regularly arranged metasurface optical elements are formed on the first surface of the first wafer, and a nanoscale microstructure unit array is formed on the surface of the metasurface optical element.

19. An optical element manufactured by the wafer-level packaging method for an optical element according to any one of claims 15 to 18, characterized in that: The optical element comprises a reconstructed wafer substrate, and a reconstructed wafer substrate surface is provided with a redistribution area and an electrical connection area electrically connected to each other; A first optical structure is disposed on the reconstructed wafer substrate, an optical functional structure is disposed on a surface of the first optical structure opposite to the reconstructed wafer substrate, and the first optical structure exposes the electrical connection area.

20. The optical element according to claim 19, characterized in that A second optical structure component is also arranged on the first optical structure component. The outer surfaces of the first optical structure component and the second optical structure component are covered with a light-shielding protective material, and the light-shielding protective material at least exposes a portion of the optical functional structure.

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