Wafer level optical element

Abstract

The utility model provides a wafer level optical element, which comprises at least two wafers arranged in parallel, at least two first matching parts and at least two second matching parts are respectively arranged on the opposite side surfaces of the two adjacent wafers, and the shapes of the first matching parts and the second matching parts are matched. The at least two first matching parts and the at least two second matching parts are arranged, so that when two adjacent wafers are overlapped, the first matching parts and the second matching parts are completely overlapped, the opposite sides of the two adjacent wafers are respectively provided with functional units arranged in an array, and the at least two first matching parts are positioned on two sides of the functional unit closest to the edge of the wafer; and the maximum length A of the projection of the first matching part on the wafer and the maximum length B of the projection of the functional unit on the wafer meet the condition that A is greater than or equal to 0.8 * B and less than or equal to 1.2 * B. According to the utility model, the problem of large overlapping error of wafers of the wafer-level optical element in the prior art is solved.

Description

Technical Field

[0001] The utility model relates to the field of wafer integration, and in particular to a wafer-level optical element. Background Art

[0002] In the current wafer stacking process, the stacking of wafers mainly relies on setting alignment marks on the wafers in advance, identifying the position of the marks through machine vision, and overlapping the alignment marks of the two wafers during stacking, so that the two wafers can be stacked with high precision. When the current alignment recognition system recognizes multiple marks, measurement errors will occur, causing the stacking position between the two wafers to shift. Since wafer stacking is an important part of wafer-level optical component manufacturing, and wafer-level optical components are constantly developing towards miniaturization, stacking accuracy is of paramount importance. Relying solely on alignment marks cannot meet the alignment accuracy requirements of actual products. Therefore, improving the alignment accuracy during wafer stacking is an important technical issue currently faced.

[0003] That is to say, the wafer-level optical elements in the prior art have the problem of large wafer overlay error. Utility Model Content

[0004] The main purpose of the utility model is to provide a wafer-level optical element to solve the problem of large wafer stacking error of the wafer-level optical element in the prior art.

[0005] In order to achieve the above-mentioned purpose, the utility model provides a wafer-level optical element, which includes at least two wafers arranged in parallel, and at least two first matching parts and at least two second matching parts are respectively arranged on the opposite side surfaces of the two adjacent wafers, and the shapes of the first matching parts match the shapes of the second matching parts so that when the two adjacent wafers are superimposed, the first matching parts and the second matching parts are completely superimposed, and the opposite sides of the two adjacent wafers respectively have functional units arranged in an array, and at least two first matching parts are located on both sides of the functional unit closest to the edge of the wafer, and the maximum length A of the projection of the first matching part on the wafer and the maximum length B of the projection of the functional unit on the wafer satisfy: 0.8*B≤A≤1.2*B.

[0006] Furthermore, a height of the first matching portion in a direction perpendicular to the wafer is greater than or equal to 50 micrometers and less than or equal to 100 micrometers.

[0007] Furthermore, at least two first matching portions are centrally symmetrically arranged on the wafer.

[0008] Furthermore, among the multiple first matching portions, a line connecting at least two of the first matching portions is a first line, and a line connecting at least another two of the first matching portions is a second line, and the first line and the second line are perpendicular to each other.

[0009] Further, the first matching portion is arranged to be raised relative to the surface of the wafer, and a cross-sectional shape of the first matching portion in a direction perpendicular to the surface of the wafer includes at least one of a triangle, a rectangle, a sawtooth, and a circle.

[0010] Further, a distance C between a center of a projection of the first matching portion on the wafer and a center of a projection of an adjacent functional unit on the wafer and a maximum length B of the projection of the functional unit on the wafer satisfy: C=B.

[0011] Furthermore, the wafer-level optical element includes at least three wafers, and a line connecting at least two first matching parts between different wafers is perpendicular to surfaces of all wafers.

[0012] Furthermore, the three wafers include a first lens wafer, a first support wafer and a second lens wafer which are arranged in sequence, and both surfaces of the first support wafer are provided with second matching parts, and the connecting line of at least two second matching parts is perpendicular to the surface of the first support wafer.

[0013] Further, the wafer-level optical element includes four wafers, and the four wafers include a third lens wafer, a second supporting wafer, a third supporting wafer and a fourth lens wafer which are arranged in sequence. A line connecting at least two second matching parts for matching the second supporting wafer with the third lens wafer or at least two second matching parts for matching the third supporting wafer with the fourth lens wafer is a third line, and a line connecting at least two second matching parts for matching the second supporting wafer with the third supporting wafer is a fourth line, and the third line and the fourth line are perpendicular to each other.

[0014] Further, the first matching portion and / or the second matching portion and / or the functional unit are embossed.

[0015] By applying the technical solution of the utility model, a wafer-level optical element comprises at least two parallel wafers, at least two first matching parts and at least two second matching parts are respectively arranged on opposite sides of the two adjacent wafers, the shapes of the first matching parts match the shapes of the second matching parts, so that when the two adjacent wafers are overlapped, the first matching parts and the second matching parts are completely overlapped, the opposite sides of the two adjacent wafers respectively have functional units arranged in an array, at least two first matching parts are located on both sides of the functional unit closest to the edge of the wafer, and the maximum length A of the projection of the first matching part on the wafer and the maximum length B of the projection of the functional unit on the wafer satisfy: 0.8*B≤A≤1.2*B.

[0016] By respectively setting the first matching part and the second matching part on the opposite side of the two wafers to be superimposed, when the two wafers are superimposed, if the alignment is accurate, the first matching part and the second matching part can be completely superimposed together, and the superposition of the two wafers is completed; if the alignment of the two wafers is not accurate, then the corresponding first matching part and the second matching part cannot be completely superimposed, and the two wafers cannot be superimposed, thereby greatly improving the alignment accuracy, reducing the time for correcting the eccentricity of the wafer, and effectively improving the efficiency of wafer superposition. At least two first matching parts are set on both sides of the functional unit at the edge of the wafer, and meet the range of 0.8*B≤A≤1.2*B, while ensuring the alignment accuracy, it is convenient for the first matching part and the second matching part to be formed on the wafer, which greatly reduces the processing cost of the first matching part and the second matching part. In addition, at least two first matching parts are located on both sides of the functional unit closest to the edge of the wafer, which can reduce the alignment eccentricity of the functional unit when the wafers are superimposed, and can also avoid interference with the functional unit, ensuring the normal operation of the wafer function. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0018] Figure 1 A cross-sectional view of a partial wafer structure of a wafer-level optical element before lamination according to an optional embodiment of the utility model is shown;

[0019] Figure 2 Shows Figure 1 A cross-sectional view of a portion of the structure after wafer stacking;

[0020] Figure 3 Shows Figure 1 A schematic diagram of the overlapping process of the first matching part and the second matching part;

[0021] Figure 4 A schematic diagram showing an angle of a lens wafer of a wafer-level optical element according to a first embodiment of the utility model is shown;

[0022] Figure 5 Shows Figure 4 A schematic diagram of an angle of a spacer wafer of wafer-level optical components;

[0023] Figure 6 Shows Figure 4 A cross-sectional view of a location of a wafer-level optical element in FIG.

[0024] Figure 7 Shows Figure 4 A cross-sectional view of another location of a wafer-level optical element in FIG.

[0025] Figure 8 A cross-sectional view showing a partial structure of a wafer-level optical element according to a second embodiment of the present utility model;

[0026] Fig. 9 A cross-sectional view showing a position of a wafer-level optical element according to a third embodiment of the present utility model;

[0027] Fig.10 Shows Fig. 9 A cross-sectional view of another location of a wafer-level optical element in FIG.

[0028] Fig.11 A cross-sectional view of a partial wafer structure of a wafer-level optical element before lamination according to a fourth embodiment of the present utility model is shown;

[0029] Fig.12 Shows Fig.11 A cross-sectional view of some structures in ;

[0030] Fig.13 A cross-sectional view of a partial wafer structure of a wafer-level optical element before lamination according to Embodiment 5 of the present utility model is shown;

[0031] Fig.14 Shows Fig.13 A cross-sectional view of some structures in ;

[0032] Fig.15 A schematic diagram showing a third connection line and a fourth connection line of an optional embodiment of the utility model is shown.

[0033] The above drawings include the following reference numerals:

[0034] 10. First matching part; 20. Second matching part; 30. Wafer; 40. Functional unit; 38. Lens wafer; 39. Spacer wafer; 31. First lens wafer; 32. First supporting wafer; 33. Second lens wafer; 34. Third lens wafer; 35. Second supporting wafer; 36. Third supporting wafer; 37. Fourth lens wafer. DETAILED DESCRIPTION

[0035] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present utility model will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0036] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0037] In the present invention, unless otherwise specified, the directional words used, such as "up, down, top, bottom", usually refer to the directions shown in the drawings, or to the components themselves in the vertical, perpendicular or gravity directions; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above-mentioned directional words are not used to limit the present invention.

[0038] In order to solve the problem of large wafer stacking error of wafer-level optical elements in the prior art, the utility model provides a wafer-level optical element.

[0039] like Figures 1 to 15 As shown, the wafer-level optical element includes at least two parallel wafers 30, and at least two first matching parts 10 and at least two second matching parts 20 are respectively arranged on the opposite side surfaces of the two adjacent wafers 30. The shapes of the first matching parts 10 and the second matching parts 20 match each other so that when the two adjacent wafers 30 are superimposed, the first matching parts 10 and the second matching parts 20 are completely superimposed. The opposite sides of the two adjacent wafers 30 have functional units 40 arranged in an array, and at least two first matching parts 10 are located on both sides of the functional unit 40 closest to the edge of the wafer 30. The maximum length A of the projection of the first matching part 10 on the wafer 30 and the maximum length B of the projection of the functional unit 40 on the wafer 30 satisfy: 0.8*B≤A≤1.2*B.

[0040] like Figures 1 to 3 As shown, by respectively setting the first matching part 10 and the second matching part 20 on the opposite side of the two wafers 30 to be superimposed, when the two wafers 30 are superimposed, if the alignment is accurate, the first matching part 10 and the second matching part 20 can be completely superimposed together, and the superposition of the two wafers 30 is completed; if the alignment of the two wafers 30 is not accurate, then the corresponding first matching part 10 and the second matching part 20 cannot be completely superimposed, and the two wafers 30 cannot be superimposed, thereby greatly improving the alignment accuracy, reducing the time for correcting the wafer eccentricity, and effectively improving the efficiency of wafer superposition. At least two first matching parts 10 are set on both sides of the functional unit 40 at the edge of the wafer 30, and meet the range of 0.8*B≤A≤1.2*B, while ensuring accurate alignment, it is convenient for the first matching part 10 and the second matching part 20 to be formed on the wafer 30, greatly reducing the processing cost of the first matching part 10 and the second matching part 20. In addition, at least two first matching parts 10 are located on both sides of the functional unit 40 closest to the edge of the wafer 30, which can reduce the eccentricity of the functional unit 40 when the wafer 30 is superimposed, and can also avoid interference with the functional unit 40, thereby ensuring the normal operation of the wafer 30 function.

[0041] Specifically, the first matching portion 10 , the second matching portion 20 , and the functional unit 40 may be formed by embossing to improve the forming stability.

[0042] Specifically, the height of the first matching portion 10 in the direction perpendicular to the wafer 30 is greater than or equal to 50 microns and less than or equal to 100 microns. By limiting the height of the first matching portion 10, the processing and structural stability of the first matching portion 10 are further guaranteed, and the functional unit 40 will not be interfered with.

[0043] Optionally, at least two first matching portions 10 are centrally symmetrically arranged on the wafer 30. This can improve the alignment efficiency, facilitate identification during the alignment process, and improve the structural stability after alignment.

[0044] Of course, it is also possible to select that among the multiple first matching parts 10, the connection line of at least two first matching parts 10 is the first connection line, and the connection line of at least another two first matching parts 10 is the second connection line, and the first connection line and the second connection line are perpendicular to each other, so as to improve the anti-mistake effect after the two wafers are superimposed.

[0045] Specifically, the first matching portion 10 is provided in a raised position relative to the surface of the wafer 30, and the cross-sectional shape of the first matching portion 10 in a direction perpendicular to the surface of the wafer 30 includes at least one of a triangle, a rectangle, a sawtooth, and a circle. The more complex the cross-sectional shape, the higher the difficulty of processing and forming, but at the same time the alignment accuracy is also higher.

[0046] like Figures 1 to 3 As shown, the distance C between the center of the projection of the first matching portion 10 on the wafer 30 and the center of the projection of the adjacent functional unit 40 on the wafer 30 and the maximum length B of the projection of the functional unit 40 on the wafer 30 satisfy: C=B. By limiting the relationship between the spacing between the first matching portion 10 and the functional unit 40 and the size of the functional unit 40, the processing and forming of the first matching portion 10 and the functional unit 40 and the structural stability can be ensured to avoid mutual interference.

[0047] Optionally, the wafer-level optical element includes at least three wafers 30, and the line connecting at least two first matching portions 10 between different wafers 30 is perpendicular to the surfaces of all wafers 30. That is, in a cross section perpendicular to the surfaces of all wafers 30, at least two first matching portions 10 between different wafers 30 are on the same straight line perpendicular to the surfaces of the wafers 30, thereby reducing the eccentricity of alignment between multiple wafers 30.

[0048] Embodiment 1

[0049] like Figures 4 to 7As shown, the wafer-level optical element includes two wafers, namely a lens wafer 38 and a spacer wafer 39. The functional unit 40 of the lens wafer 38 is a single lens, and the functional unit 40 of the spacer wafer 39 is a light-through hole. The functional units of the lens wafer 38 and the functional units of the spacer wafer 39 are arranged in a one-to-one correspondence.

[0050] The lens wafer 38 has a first mating portion 10 on one side facing the spacer wafer 39. Two first mating portions 10 are located on both sides of the lens at the edge of the lens wafer 38 and are in the same straight line as the multiple lenses at the edge. Two other first mating portions 10 are arranged symmetrically with the above two first mating portions 10.

[0051] Correspondingly, a plurality of second matching portions 20 are disposed on the spacer wafer 39 , and the position of each second matching portion 20 is arranged in one-to-one correspondence with the first matching portion 10 to be overlapped therewith.

[0052] Specifically, the first matching portion 10 is a cone protruding relative to the surface of the wafer, and the second matching portion 20 is a conical groove arranged in the same shape, that is, the cross-sectional shape of the first matching portion 10 in the direction perpendicular to the surface of the wafer 30 is a triangle. After the first matching portion 10 and the second matching portion 20 are completely overlapped, a complete cylinder is formed, which also means that the lens wafer 38 and the spacer wafer 39 are successfully aligned and overlapped.

[0053] Optionally, the height of the first matching portion 10 is consistent with the height of the lens, which can be selected to be 50 microns to 100 microns, the bottom diameter is generally 100 microns, and the distance between the center of the first matching portion 10 and the center of the adjacent lens is also 100 microns.

[0054] Embodiment 2

[0055] The difference from the first embodiment is that the number of wafer-level optical elements included is different.

[0056] like Figure 8 As shown, the wafer-level optical element includes three wafers, which are a first lens wafer 31, a first support wafer 32, and a second lens wafer 33 arranged in sequence. The two surfaces of the first support wafer 32 are both provided with second matching parts 20, and the connecting line of at least two second matching parts 20 is perpendicular to the surface of the first support wafer 32. In other words, the first lens wafer 31 and the second lens wafer 33 are both provided with first matching parts 10 on one side facing the first support wafer 32, and they are respectively matched with the second matching parts 20 on the first support wafer 32. In the process of stacking the first lens wafer 31, the first support wafer 32, and the second lens wafer 33, the first matching parts 10 and the second matching parts 20 corresponding to each other are completely overlapped to achieve the stacking of the three wafers.

[0057] Embodiment 3

[0058] The difference from the first embodiment is that the number of wafer-level optical elements included is different.

[0059] like Fig. 9 and Fig.10 As shown, the wafer-level optical element includes four wafers, and the four wafers include a third lens wafer 34, a second support wafer 35, a third support wafer 36 and a fourth lens wafer 37 which are arranged in sequence. The line between at least two second matching parts for matching the second support wafer 35 and the third lens wafer 34 or at least two second matching parts for matching the third support wafer 36 and the fourth lens wafer 37 is a third line, and the line between at least two second matching parts for matching the second support wafer 35 and the third support wafer 36 is a fourth line, and the third line and the fourth line are perpendicular to each other.

[0060] That is to say, the second matching part between the lens wafer and the supporting wafer can be connected to form a third line, and the second matching part between the supporting wafer and the supporting wafer can be connected to form a fourth line. The third line and the fourth line are perpendicular, that is, the two skewed straight lines are perpendicular to each other. While improving the alignment accuracy of multiple wafers and reducing the eccentricity problem, the anti-fouling effect after stacking multiple wafers can be further improved.

[0061] like Fig.15 A solid line connecting two second matching parts for matching the second support wafer 35 and the third lens wafer 34 is shown. The solid line is the third connecting line. The figure also uses a dotted line to schematically represent the connection between two second matching parts for matching the second support wafer 35 and the third support wafer 36. The dotted line is the fourth connecting line. The third connecting line and the fourth connecting line are perpendicular to each other.

[0062] Embodiment 4

[0063] The difference from the first embodiment is that the shapes of the first matching portion 10 and the second matching portion 20 are different.

[0064] like Fig.11 and Fig.12 As shown, the cross-sectional shape of the first matching portion 10 is a combination of a rectangle and a sawtooth. Compared with the triangular structure, the first matching portion 10 of this embodiment is more complicated to process and more difficult to form, but the wafer alignment accuracy is also higher.

[0065] Embodiment 5

[0066] The difference from the first embodiment is that the shapes of the first matching portion 10 and the second matching portion 20 are different.

[0067] like Fig.13 and Fig.14 As shown, the cross-sectional shape of the first matching portion 10 is a parabola, which can also ensure the alignment accuracy.

[0068] From the above description, it can be seen that the above embodiments of the utility model achieve the following technical effects:

[0069] 1. By arranging a first matching portion and a second matching portion that match each other between two wafers, the alignment accuracy between the wafers can be improved, the time for correcting the eccentricity of the wafers can be reduced, and the efficiency of wafer stacking can be effectively improved.

[0070] 2. By providing the first matching parts on both sides of the functional unit located at the edge of the wafer, the eccentricity of the functional unit when the wafers are stacked can be reduced, and interference with the functional unit can be avoided.

[0071] 3. Providing at least two first matching parts symmetrically relative to the center of the wafer can further improve the alignment efficiency and the fool-proofing effect.

[0072] Obviously, the embodiments described above are only some embodiments of the utility model, not all embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0073] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0074] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0075] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A wafer-level optical element, characterized in that: The wafer-level optical element comprises at least two wafers (30) arranged in parallel, at least two first matching parts (10) and at least two second matching parts (20) are respectively arranged on opposite side surfaces of two adjacent wafers (30), the shapes of the first matching parts (10) and the second matching parts (20) match each other so that when the two adjacent wafers (30) are superimposed, the first matching parts (10) and the second matching parts (20) are completely superimposed, and the opposite sides of the two adjacent wafers (30) are respectively provided with functional units (40) arranged in an array, at least two of the first matching parts (10) are located on both sides of the functional unit (40) closest to the edge of the wafer (30), and the maximum length A of the projection of the first matching part (10) on the wafer (30) and the maximum length B of the projection of the functional unit (40) on the wafer (30) satisfy the following relationship: 0.8*B≤A≤1.2*B.

2. The wafer-level optical element according to claim 1, characterized in that: The height of the first matching portion (10) in a direction perpendicular to the wafer (30) is greater than or equal to 50 micrometers and less than or equal to 100 micrometers.

3. The wafer-level optical element according to claim 1, characterized in that: At least two of the first matching parts (10) are centrally symmetrically arranged on the wafer (30).

4. The wafer-level optical element according to claim 3, characterized in that: Among the plurality of first matching parts (10), a line connecting at least two of the first matching parts (10) is a first line, and a line connecting at least another two of the first matching parts (10) is a second line, and the first line and the second line are perpendicular to each other.

5. The wafer-level optical element according to claim 1, characterized in that: The first matching portion (10) is arranged to be raised relative to the surface of the wafer (30), and the cross-sectional shape of the first matching portion (10) in a direction perpendicular to the surface of the wafer (30) includes at least one of a triangle, a rectangle, a sawtooth shape, and a circle.

6. The wafer-level optical element according to claim 1, characterized in that: The distance C between the center of the projection of the first matching portion (10) on the wafer (30) and the center of the projection of the adjacent functional unit (40) on the wafer (30) and the maximum length B of the projection of the functional unit (40) on the wafer (30) satisfy the following relationship: C=B.

7. The wafer-level optical element according to claim 1, characterized in that: The wafer-level optical element comprises at least three wafers, and a line connecting at least two of the first matching parts (10) located between different wafers (30) is perpendicular to surfaces of all the wafers (30).

8. The wafer-level optical element according to claim 7, characterized in that: The three wafers include a first lens wafer (31), a first support wafer (32) and a second lens wafer (33) which are arranged in sequence, the two surfaces of the first support wafer (32) are both provided with the second matching parts (20), and the connecting line of at least two of the second matching parts (20) is perpendicular to the surface of the first support wafer (32).

9. The wafer-level optical element according to claim 7, characterized in that: The wafer-level optical element comprises four wafers, wherein the four wafers comprise a third lens wafer (34), a second support wafer (35), a third support wafer (36) and a fourth lens wafer (37) which are arranged in sequence, a line connecting at least two second matching parts (20) for matching the second support wafer (35) with the third lens wafer (34) or at least two second matching parts (20) for matching the third support wafer (36) with the fourth lens wafer (37) is a third line, and a line connecting at least two second matching parts (20) for matching the second support wafer (35) with the third support wafer (36) is a fourth line, and the third line and the fourth line are perpendicular to each other.

10. The wafer-level optical element according to any one of claims 1 to 9, characterized in that: The first matching portion (10) and / or the second matching portion (20) and / or the functional unit (40) are embossed.

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