JP5254139B2 - Multilayer lens, laminated wafer lens, and manufacturing method thereof - Google Patents

Description

  The present invention relates to a wafer scale lens structure and an adhesive structure of a laminated wafer lens in which a plurality of wafer scale lenses are stacked, and more particularly to a stacked wafer lens in which a plurality of wafer scale lenses are stacked and a multilayer lens in which the wafer scale lenses are individually divided. And a method of manufacturing a laminated wafer lens.

  With the widespread use of mobile phones with cameras, digital still cameras, surveillance cameras, and the like, the demand for solid-state imaging devices specified for them has increased, and the demand for miniaturization has increased due to the necessity of application. As one method for reducing the size, there has been proposed a method for forming a wafer scale camera module in which a semiconductor chip having a lens mounted on a semiconductor chip and the lens are integrated. The wafer scale camera module can reduce the manufacturing cost by forming a laminated wafer lens in which a plurality of wafer scale lenses are bonded together.

  However, when manufacturing a laminated wafer lens, it is not easy to superimpose the wafer scale lenses, so that a positional shift or inclination occurs between the wafer scale lenses. This positional deviation or inclination is the largest cause of deterioration of the lens characteristics of the laminated wafer lens. In other words, a laminated wafer lens formed of a plurality of wafer scales has a deviation of the center position of each wafer scale lens (deviation of the optical axis) and a deviation of the distance (height) between the wafer scale lenses. However, the lens characteristics are deteriorated. Therefore, it is indispensable for the laminated wafer lens to superimpose the wafer scale lens with very high accuracy.

  Thus, for example, Patent Document 1 discloses a wafer scale lens bonding method. In Patent Document 1, in order to increase the accuracy of alignment of a wafer scale lens (optical element substrate), the wafer scale lens is bonded by an adhesive applied to the periphery of the wafer scale lens optical unit. FIG. 7A and FIG. 7B are cross-sectional views showing a schematic configuration of the laminated wafer lens disclosed in Patent Document 1.

  Specifically, in the method illustrated in FIG. 7A, first, an ultraviolet curable adhesive 103 is applied around the optical portion of the wafer scale lens 101. Next, alignment is performed so that alignment marks (not shown) formed on the wafer scale lenses 101 and 102 overlap. When the wafer scale lens 101 and the wafer scale lens 102 are overlapped and bonded together, the ultraviolet curable adhesive 103 is cured by ultraviolet irradiation. Thereby, the wafer scale lens 101 and the wafer scale lens 102 are mutually fixed.

  On the other hand, the method illustrated in FIG. 7B uses an adhesive 105 including spacer particles 105a instead of the ultraviolet curable adhesive 103 in FIG. 7A. Different from the method.

JP 11-248989 A (published September 17, 1999)

  However, in the method of Patent Document 1, the distance between the wafer scale lenses is not constant, or positional deviation or inclination occurs between the wafer scale lenses. For this reason, there is a problem that it is impossible to manufacture a laminated wafer lens in which wafer scale lenses are superimposed with high accuracy.

  Specifically, in the method illustrated in FIG. 7A, the adhesive 103 exists between the wafer scale lenses 101 and 102. For this reason, variations in the application amount, viscosity, and concentration of the ultraviolet curable adhesive 103 cause variations in the thickness of the ultraviolet curable adhesive 103. As a result, the distance (height) between the wafer scale lenses 101 and 102 cannot be made constant. Further, the wafer scale lenses 101 and 102 cannot be bonded in parallel. For this reason, positional deviation and inclination also occur between the wafer scale lenses 101 and 102, leading to optical axis deviation.

  On the other hand, in the method described in FIG. 7B, it is intended that the distance (height) between the wafer scale lenses 101 and 102 is made constant by the spacer particles 105a. However, this distance varies greatly depending on the overlap of the spacer particles 105a. In the laminated wafer lens, even if the accuracy (variation) of this distance is only about 50 μm, it greatly affects the deterioration of the lens characteristics. The spacer particles 105a are usually about 50 μm. Therefore, even with the method shown in FIG. 7B, the distance (height) between the wafer scale lenses 101 and 102 cannot be made constant to such an extent that the lens characteristics are not affected.

  Furthermore, in the case of the method shown in FIG. 7A, when the wafer scale lenses 101 and 102 are overlapped, the wafer scale lenses 101 and 102 are temporarily bonded. Further, even with the method shown in FIG. 7B, the spacer particles 105a cannot have no adhesive property. For this reason, when the wafer scale lenses 101 and 102 are overlapped, the wafer scale lenses 101 and 102 are temporarily bonded. That is, in any method, once the wafer scale lenses 101 and 102 are overlapped, the position of the wafer scale lenses 101 and 102 cannot be changed. Therefore, even if the wafer scale lenses 101 and 102 are bonded while the centers (optical axes) are shifted, or are bonded while the distance between the wafer scale lenses 101 and 102 is shifted, the shift cannot be corrected. Therefore, the lens characteristics of the laminated wafer lens cannot be satisfied, resulting in a defective product.

  In the method of Patent Document 1, the wafer scale lenses 101 and 102 are bonded at the same time as the wafer scale lenses 101 and 102 are overlapped. For this reason, in order to securely bond, it is necessary to apply a load corresponding to the adhesives 103 and 105 to the wafer scale lenses 101 and 102 for a certain period of time when they are overlapped. However, depending on the ultraviolet curable adhesive 103 and the adhesive 105, excessive load is required. For this reason, even when the load is applied, there may be a positional deviation or inclination between the wafer scale lenses 101 and 102.

  The present invention has been made in view of the above-described problems, and a purpose of the present invention is to provide a laminated wafer lens in which wafer scale lenses are superimposed with high accuracy, a manufacturing method thereof, and a divided wafer lens. Is to provide a multilayer lens.

In order to solve the above-described problem, a laminated wafer lens according to the present invention is a laminated wafer lens in which a plurality of wafer scale lenses each having a plurality of lens optical units are overlapped, and two wafer scales adjacent to each other. In at least one of the lenses, a groove connecting both ends of the opposite surface is formed on the surface facing the other, avoiding the lens optical portion, and adjacent to each other except for the portion where the groove is formed. The opposing surfaces of the two wafer scale lenses are in contact with each other, and the groove is filled with an adhesive, and the groove is formed on any opposing surface of the two wafer scale lenses adjacent to each other. The grooves formed in each of the two wafer scale lenses adjacent to each other overlap each other, and the two wafer scale lenses adjacent to each other are overlapped. Each opposing surface of the are in direct contact with each other except where the groove and the lens optic portion is formed, is characterized in that the contact portion of one another are in surface contact.

  According to the said structure, the groove | channel is formed in the opposing surface (adhesion surface) with respect to at least one of the adjacent wafer scale lenses. And the adjacent wafer scale lens is adhere | attached with the adhesive agent with which the groove | channel was filled. Further, in the portion where the groove is not formed, the opposing surfaces of adjacent wafer scale lenses are in direct contact with each other. For this reason, there is no adhesive between the opposing surfaces. That is, the thickness of the adhesive is not related to the distance between the wafer scale lenses. Therefore, the distance between the wafer scale lenses can be made constant.

  In addition, since there is no adhesive between the opposing surfaces of adjacent wafer scale lenses, the position of the superimposed wafer scale lenses can be changed before bonding. That is, after correcting the position so as to satisfy the characteristics of the stacked wafer lens, the wafer scale lens can be bonded after being overlapped. Accordingly, there is no positional deviation or tilt between the wafer scale lenses.

  As described above, according to the above configuration, the distance between the wafer scale lenses is kept constant, and the positional deviation or the inclination between the wafer scale lenses does not occur. Therefore, it is possible to realize a laminated wafer lens in which wafer scale lenses are superimposed with high accuracy.

Moreover, according to the said structure, the groove | channel is formed in any opposing surface of an adjacent wafer scale lens. As a result, the bonding area becomes wider than when a groove is formed on one of the wafer scale lenses. Therefore, the adhesive strength can be increased.

Moreover, according to the said structure, the groove | channel is formed in any opposing surface of an adjacent wafer scale lens. Furthermore, the grooves formed on the opposing surfaces overlap each other, and the grooves are connected. Thereby, it is possible to simultaneously fill the overlapping grooves with the adhesive. Therefore, the adhesive filling process (filling time) can be shortened while widening the adhesive region to increase the adhesive strength.

  In the laminated wafer lens, it is preferable that the groove is formed so as to surround a lens optical portion of the wafer scale lens.

  According to the above configuration, the lens optical part of each wafer scale lens is sealed by the adhesive filled in the groove. Accordingly, the adhesive can prevent dust from entering the lens optical unit from the outside.

  In the multilayer wafer lens, the groove is preferably formed so as to include a cutting region for dividing the multilayer wafer lens into individual multilayer lenses.

  According to the said structure, the groove | channel is formed so that the cutting area | region divided | segmented into each multilayer lens may be included. Thereby, when the multilayer wafer lens is cut along the cutting region to form a multilayer lens, the adhesive remains on the side surface of the cut multilayer lens. For this reason, the adhesion state of the laminated wafer lens is also maintained in the cut multilayer lens. Accordingly, it is possible to manufacture a multilayer lens in which the lens optical parts are superimposed with high accuracy.

  In the laminated wafer lens, the groove is preferably formed so as to be shared between adjacent multilayer lenses.

  According to the said structure, the groove | channel formed so that a cutting area | region may be included is shared between adjacent multilayer lenses. Thereby, favorable adhesion | attachment is realizable, reducing the number of grooves.

  The multilayer lens of the present invention is obtained by dividing one of the above laminated wafer lenses. That is, the multilayer lens of the present invention is obtained by dividing a laminated wafer lens in which wafer scale lenses are superimposed with high accuracy into individual pieces. Accordingly, it is possible to realize a multilayer lens in which the lens optical parts are laminated with high accuracy.

  A method for manufacturing a laminated wafer lens according to the present invention is a method for producing any one of the above laminated wafer lenses, wherein a lamination step of superposing a plurality of wafer scale lenses and a position of the laminated wafer scale lenses are arranged. It includes a position adjusting process for adjusting, and an adhering process for adhering the overlapped wafer scale lens with an adhesive filled in the groove.

  According to said method, after performing a position adjustment process, an adhesion process is performed. For this reason, even if a positional deviation or inclination occurs between the wafer scale lenses superimposed in the laminating process, the positional deviation or inclination can be corrected in the position adjusting process. Thereby, the wafer scale lens can be bonded after correcting the position so as to satisfy the characteristics of the laminated wafer lens. Therefore, it is possible to manufacture a laminated wafer lens in which wafer scale lenses are superimposed with high accuracy.

In the laminated wafer lens of the present invention, a groove is formed on the facing surface of at least one of the two wafer scale lenses adjacent to each other, the groove is filled with an adhesive, and Except for the portion where the groove is formed, the opposing surfaces of two adjacent wafer scale lenses are in contact with each other. In addition to this configuration, in the laminated wafer lens of the present invention, the groove is formed on any facing surface of the two wafer scale lenses adjacent to each other, and the groove of the two wafer scale lenses adjacent to each other is formed. The grooves formed in each of them overlap each other, and the opposing surfaces of the two wafer scale lenses adjacent to each other are in direct contact with each other except for the portion where the groove and the lens optical unit are formed. This is a configuration in which the contact portion is in surface contact. Therefore, it is possible to realize a laminated wafer lens in which wafer scale lenses are superimposed with high accuracy.

It is a perspective view which shows schematic structure of the lamination type wafer lens of this invention. FIG. 2 is an exploded cross-sectional view of the multilayer wafer lens of FIG. 1. It is a top view which shows the wafer scale lens which comprises the lamination type wafer lens of FIG. It is sectional drawing which shows the manufacturing process of the laminated wafer lens of FIG. (A) And (b) is sectional drawing which decomposed | disassembled another lamination type wafer lens of this invention. (A) And (b) is sectional drawing which decomposed | disassembled another laminated wafer lens of this invention. (A) And (b) is sectional drawing which shows schematic structure of the laminated wafer lens of patent document 1. As shown in FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. First, a laminated wafer lens according to an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is a perspective view showing a schematic structure of a laminated wafer lens 20 of the present embodiment. As shown in the figure, the laminated wafer lens 20 is formed by superposing two disk-shaped wafer scale lenses 201 and 202 adjacent to each other. The wafer scale lenses 201 and 202 have a plurality of lens optical units. Specifically, the wafer scale lens 201 has a plurality of lens optical units 201a arranged in a matrix. Although not shown, the wafer scale lens 202 is similarly formed with a plurality of lens optical units corresponding to the lens optical units 201a. Wafer scale lenses 201 and 202 are formed of a material such as glass or resin.

  As for wafer scale lenses 201 and 202, concave grooves (grooves) 201b and 202b are formed on the surfaces facing each other. The concave grooves 201 b and 202 b are filled with an adhesive 203, and the wafer scale lenses 201 and 202 are bonded by the adhesive 203. Details of the concave grooves 201b and 202b will be described later.

  The opposing surfaces of the wafer scale lenses 201 and 202 are in direct contact with each other except for the portions where the concave grooves 201b and 202b are formed. For this reason, except for the portion where the concave grooves 201b and 202b are formed, the contact portion 201c of the wafer scale lens 201 with the wafer scale lens 202 and the contact portion 202c of the wafer scale lens 202 with the wafer scale lens 201 are mutually connected. Surface contact. Therefore, the adhesive 203 does not exist between the contact portions 201c and 202c.

  Next, the laminated wafer lens 20 will be described in detail with reference to FIGS. FIG. 2 is an exploded cross-sectional view of the laminated wafer lens 20 and shows a schematic configuration of the wafer scale lenses 201 and 202. FIG. 3 is a plan view of the wafer scale lens 202. FIG. 4 is a cross-sectional view of the laminated wafer lens 20.

  As shown in FIG. 2, a concave groove 201b is formed on the back surface of the wafer scale lens 201 (the surface facing the wafer scale lens 202). The concave groove 201b is formed so as to avoid each lens optical part 201a. Furthermore, the concave grooves 201b are formed in a plurality of rows from the end of the back surface of the wafer scale lens 201 to the end.

  A concave groove 202b similar to the concave groove 201b is also formed on the front surface of the wafer scale lens 202 (the surface facing the wafer scale lens 201). That is, the lens optical unit 202 a is formed on the front surface of the wafer scale lens 202 at a position corresponding to the lens optical unit 201 a of the wafer scale lens 201. The concave groove 202b is formed avoiding the lens optical part 202a. Further, the concave grooves 202b are formed in a plurality of rows from end to end of the front surface of the wafer scale lens 202.

  The concave grooves 201b and 202b are not particularly limited as long as they are formed so as to avoid the lens optical portions 201a and 202a. In the laminated wafer lens 20 of the present embodiment, the concave grooves 201b and 202b have the following characteristic configuration.

Specifically, FIG. 3 is a plan view (top view) showing the wafer scale lens 202 constituting the multilayer wafer lens 20. In the laminated wafer lens 20, the concave grooves 202 b are formed in a lattice shape on the front surface of the wafer scale lens 202 (the surface facing the wafer scale lens 201). That is, as shown in the figure, a plurality of concave grooves 202b orthogonal to the vertical direction and the horizontal direction are formed. Therefore, in the wafer scale lens 202 in FIG. 3, the lens optical portion 202a is surrounded by the groove 202b. On the other hand, a lattice-shaped concave groove 201b is formed on the back surface of the wafer scale lens 201 as well. Thereby, when the contact part 201c of the wafer scale lens 201 and the contact part 202c of the wafer scale lens 202 are overlapped, a space in which both ends are opened is formed by the concave grooves 201b and 202b. Specifically, a space that crosses or longitudinally extends in a parallel direction with respect to the opposing surfaces of the wafer scale lenses 201 and 202 is formed.

  Further, in the laminated wafer lens 20, when the contact portion 201c and the contact portion 202c are overlapped, the concave groove 201b and the concave groove 202b overlap each other (see the broken line portion in FIG. 2). . That is, a single (common) concave groove in which the concave groove 201b and the concave groove 202b are connected is formed. More specifically, in the present embodiment, as shown in FIG. 2, each of the concave groove 201b and the concave groove 202b has a semicircular cross section in the optical axis direction. When the wafer scale lenses 201 and 202 are overlapped, as shown in FIG. 4, the groove 201b and the groove 201b having a semicircular cross section in the optical axis direction overlap, and the cross section becomes a circle (or an ellipse). Accordingly, the overlapping concave grooves 201b and 202b form a bottomless cylindrical hollow space that crosses the opposing surfaces of the wafer scale lenses 201 and 202 in a parallel direction. The wafer scale lenses 201 and 202 are bonded by an adhesive 203 filled in this space.

  Further, as will be described later, as shown in FIG. 4, the laminated wafer lens 20 is finally cut by the dicing blade 10 or the like and divided into individual multilayer lenses B. The multilayer lens B exhibits a lens function by the laminated lens optical unit 201a and lens optical unit 202a. In the laminated wafer lens 20, the concave groove 201b and the concave groove 201b are formed so as to include a cutting line (cutting region) by the dicing blade 10. Moreover, the concave groove 201b and the concave groove 201b are shared between the multilayer lenses B adjacent to each other.

  As described above, in the laminated wafer lens 20, the concave grooves 201b and 202b are formed on the mutually opposing surfaces (adhesion surfaces) of the wafer scale lenses 201 and 202, respectively. Adjacent wafer scale lenses 201 and 202 are bonded by an adhesive 203 filled in the groove. Further, in the portions where the concave grooves 201b and 202b are not formed, the opposing surfaces of the wafer scale lenses 201 and 202 (contact portions 201c and 202c) are in direct contact with each other, and therefore between the contact portions 201c and 202c. There is no adhesive 203. For this reason, the thickness of the adhesive 203 is not related to the distance (height) between the wafer scale lenses 201 and 202. Further, since the contact portion 201c of the wafer scale lens 201 and the contact portion 202c of the wafer scale lens 202 are in surface contact with each other, the wafer scale lenses 201 and 202 are parallel to each other. Accordingly, the distance between the wafer scale lenses 201 and 202 is constant at any part.

  Moreover, since the adhesive 203 does not exist between the contact portions 201c and 202c, the concave grooves 201b and 202b are overlapped if the adhesive 203 is not filled or the adhesive 203 is filled and temporarily bonded. The positions of the wafer scale lenses 201 and 202 can be changed. That is, the wafer scale lenses 201 and 202 can be bonded after the wafer scale lenses 201 and 202 are superimposed after the position is corrected so as to satisfy the characteristics of the laminated wafer lens 20. Accordingly, there is no positional deviation or tilt between the wafer scale lenses 201 and 202.

  Therefore, according to the laminated wafer lens 20, it is possible to realize the laminated wafer lens 20 in which the wafer scale lenses are superimposed with high accuracy.

  In the laminated wafer lens 20, concave grooves 201 b and 202 b are formed on the opposing surfaces of the wafer scale lenses 201 and 202. As a result, the bonding area becomes wider than when a groove is formed on one of the wafer scale lenses. Therefore, the adhesive strength can be increased.

  Next, a method for manufacturing the laminated wafer lens 20 will be described with reference to FIGS. The laminated wafer lens 20 includes a laminating process for superimposing the wafer scale lenses 201 and 202, a position adjusting process for adjusting the positions of the laminated wafer scale lenses 201 and 202, and an adhesive filled in the concave grooves 201b and 202b. The wafer scale lenses 201 and 202 whose positions have been adjusted can be manufactured by a bonding process.

  Specifically, first, in the stacking step, the wafer scale lens 201 and the wafer scale lens 202 are superposed as shown in FIG. That is, the contact part 201 c of the wafer scale lens 201 is disposed on the contact part 202 c of the wafer scale lens 202. Thereby, the ditch | groove 201b and the ditch | groove 202b overlap.

  Next, in the position adjustment step, the characteristics of the laminated wafer lens 20 are measured before the wafer scale lenses 201 and 202 that are overlapped are bonded. For example, it is confirmed by measurement whether or not the optical axis misalignment of the wafer scale lenses 201 and 202 (displacement of the lens optical units 201a and 202a is stopped) or the tilt occurs. Then, when necessary characteristics are not obtained due to deviation or inclination of the optical axis, the relative positions of the wafer scale lenses 201 and 202 are adjusted so as to satisfy the necessary characteristics. For example, the stacking process is performed again, and the wafer scale lenses 201 and 202 are overlapped.

  In the laminated wafer lens 20, the contact portion 201 c of the wafer scale lens 201 is disposed directly on the contact portion 202 c of the wafer scale lens 202, so the distance between the wafer scale lenses 201 and 202 is basically the same. It is constant. However, there is a possibility that dust or the like exists on the contact portion 201c or the contact portion 202c and the distance is shifted. For this reason, when measuring the characteristics of the laminated wafer lens 20, it is preferable to measure the distance.

  Finally, as shown in FIG. 4, in the bonding step, the adhesive 203 is filled into the concave grooves 201 b and 202 b of the wafer scale lenses 201 and 202 that have been position-adjusted in the position adjustment step. As described above, the concave grooves 201b and 202b form spaces in which both ends are opened in a direction parallel to the opposing surfaces of the wafer scale lenses 201 and 202. For this reason, for example, the adhesive 203 can be injected into the space from the side of the laminated wafer lens 20. As described above, the concave grooves 201b and 202b are formed so as to avoid the lens optical parts 201a and 202a, and the contact part 201c and the contact part 201c are in direct contact with each other. For this reason, even if the concave grooves 201b and 202b are filled with the adhesive 203, the adhesive 203 does not flow into the lens optical portions 201a and 202a.

  In this way, the manufacture of the laminated wafer lens 20 is completed. As shown in FIG. 4, the multilayer wafer lens 20 is divided into individual multilayer lenses B by cutting between adjacent multilayer lenses B by a dicing blade 10.

  As described above, since the bonding process is performed after the position adjusting process, even if a positional shift or inclination occurs between the wafer scale lenses 201 and 202 superimposed in the stacking process, The positional deviation or inclination can be corrected. As a result, the wafer scale lenses 201 and 202 can be bonded together after correcting the position so as to satisfy the characteristics of the laminated wafer lens 20. The laminated wafer lens 20 can be manufactured by superimposing the wafer scale lenses 201 and 202 under the best characteristics. Therefore, it is possible to manufacture the laminated wafer lens 20 in which the wafer scale lenses 201 and 202 are superimposed with high accuracy. Further, by dividing the multilayer wafer lens 20 into individual multilayer lenses B, the multilayer lens B in which the lens optical parts 201a and 202a are laminated with high accuracy can be realized.

  In the laminated wafer lens 20, when the wafer scale lens 201 and the wafer scale lens 202 are overlapped in the lamination step, the concave grooves 201 b and 202 b overlap each other and the concave grooves 201 b and 202 b are connected to each other ( A common groove is formed. For this reason, the adhesive 203 can be simultaneously filled into the concave grooves 201b and 202b. Therefore, the filling process (filling time) of the adhesive 203 can be shortened while widening the bonding region to increase the bonding strength.

  As shown in FIG. 3, in the laminated wafer lens 20, the concave grooves 201 b and 202 b are formed so as to surround the lens optical parts 201 a and 202 a of the wafer scale lenses 201 and 202. Therefore, when the concave grooves 201b and 202b are filled with the adhesive 203, the lens optical parts 201a and 202a are sealed by the filled adhesive 203. Therefore, the filled adhesive 203 can prevent dust from entering the lens optical parts 201a and 202a from the outside.

  Further, as shown in FIG. 4, the concave grooves 201 b and 202 b are formed so as to include a cutting line (cutting region) that is divided into individual multilayer lenses B. That is, the width of the concave grooves 201 b and 202 b is larger than the width of the dicing blade 10. Thereby, when the multilayer wafer lens 20 is formed by cutting the laminated wafer lens 20 along the cutting region by the dicing blade 10, the adhesive 203 remains on the side surface of the multilayer lens B after cutting. For this reason, the adhesion state of the laminated wafer lens 20 is also maintained in the cut multilayer lens B. Accordingly, it is possible to manufacture the multilayer lens B in which the lens optical parts 201a and 202a are overlapped with high accuracy.

  Further, as shown in FIG. 4, the concave grooves 201b and 202b are shared between the multilayer lenses B adjacent to each other. Thereby, favorable adhesion | attachment is realizable, reducing the number of the concave grooves 201b and 202b.

  As shown in FIG. 4, in the laminated wafer lens 20, when the concave grooves 201b and 202b overlap, the cross section in the optical axis direction becomes a circle (or an ellipse). For this reason, the adhesive 203 can be filled uniformly. Further, when the cross section is a circle (or an ellipse), it becomes strong against stress.

  Further, the position of the wafer scale lenses 201 and 202 can be corrected immediately after the adhesive 203 is filled in the bonding process. That is, the position adjustment process can be performed again. Thereby, the laminated wafer lens 20 in which the wafer scale lenses 201 and 202 are superimposed with higher accuracy can be manufactured.

  Further, the position adjustment process and the adhesion process can be performed simultaneously. That is, after the two wafer scale lenses 201 and 202 are overlapped by the stacking process, the concave grooves 201b and 202b are filled with the adhesive 203, and the adjustment of the position of the wafer scale lenses 201 and 202 can be adjusted. .

  The concave grooves 201b and 202b of the laminated wafer lens 20 can be configured as follows. FIGS. 5 (a), 5 (b), 6 (a), and 6 (b) are cross-sectional views showing structures obtained by disassembling other laminated wafer lenses 30, 30 ′, 40, and 40 ′, respectively. FIG. Even with the following configuration, similarly to the laminated wafer lens 20, it is possible to realize laminated wafer lenses 30, 30 ', 40, and 40' in which wafer scale lenses are superimposed with high accuracy. Hereinafter, the difference from the laminated wafer lens 20 will be mainly described.

  In the laminated wafer lens 20, when the wafer scale lens 201 and the wafer scale lens 202 are superposed, the concave groove 201b and the concave groove 202b overlap each other.

  On the other hand, in the laminated wafer lens 30 of FIG. 5A, when the wafer scale lens 301 and the wafer scale lens 302 are overlapped, a part of the groove 301b and a part of the groove 302b overlap. Also in the laminated wafer lens 30, a single (common) concave groove in which the concave groove 301b and the concave groove 302b are connected is formed by the concave groove 301b and the concave groove 302b. For this reason, it is possible to simultaneously fill the concave grooves 301b and 302b with an adhesive (not shown). Therefore, the adhesive filling process (filling time) can be shortened while widening the adhesive region to increase the adhesive strength.

  On the other hand, as shown in FIG. 5B, in the laminated wafer lens 30, when the wafer scale lens 301 and the wafer scale lens 302 are overlapped, the concave groove 301b and the concave groove 302b do not overlap at all. In this case, an adhesive (not shown) is formed in the space formed by the concave groove 301b and the front surface of the wafer scale lens 302, and in the space formed by the concave groove 302b and the back surface of the wafer scale lens 301. In other words, a stacked wafer lens 30 ′ in which the wafer scale lenses 301 and 302 are superimposed with high accuracy can be realized.

  In the laminated wafer lens 20, a concave groove 201 b is formed in the wafer scale lens 201, and a concave groove 202 b is formed in the wafer scale lens 202. However, the concave grooves 201b and 202b may be formed in at least one of the wafer scale lenses 201 and 202.

  That is, in the laminated wafer lens 40 of FIG. 6A, the concave surface 201b is formed on the back surface of the wafer scale lens 201, whereas the front surface of the wafer scale lens 401 (with the wafer scale lens 201). No concave groove is formed on the facing surface. Also in this case, similarly to the laminated wafer lens 30 ′, the space formed by the concave groove 201b and the front surface of the wafer scale lens 401 is filled with an adhesive (not shown), thereby increasing the height. It is possible to realize a laminated wafer lens 40 ′ in which the wafer scale lenses 201 and 401 are overlapped with accuracy.

  On the other hand, in the laminated wafer lens 40 ′ of FIG. 6B, conversely, no concave groove is formed on the back surface of the wafer scale lens 402, whereas the front surface (wafer scale) of the wafer scale lens 202 is formed. On the surface facing the lens 402, a concave groove 202b is formed. In this case as well, like the laminated wafer lens 30 ′, the space formed by the concave groove 202b and the back surface of the wafer scale lens 402 is filled with an adhesive (not shown) so that the wafer can be obtained with high accuracy. A stacked wafer lens 40 ′ in which the scale lenses 201 and 401 are superimposed can be realized.

The multilayer wafer lens according to the present invention is a multilayer wafer lens in which a plurality of wafer scale lenses each having a plurality of lens optical units are overlapped, and at least one of two wafer scale lenses adjacent to each other is the other. Grooves that connect both ends of the facing surface are formed on the facing surface of the two wafer scale lenses so as to avoid the lens optical portion, and each of the two wafer scale lenses adjacent to each other except for the portion where the groove is formed. The surfaces may be in contact with each other, and the groove may be filled with an adhesive.

  According to the said structure, the groove | channel is formed in the opposing surface (adhesion surface) with respect to at least one of the adjacent wafer scale lenses. And the adjacent wafer scale lens is adhere | attached with the adhesive agent with which the groove | channel was filled. Further, in the portion where the groove is not formed, the opposing surfaces of adjacent wafer scale lenses are in direct contact with each other. For this reason, there is no adhesive between the opposing surfaces. That is, the thickness of the adhesive is not related to the distance between the wafer scale lenses. Therefore, the distance between the wafer scale lenses can be made constant.

  In addition, since there is no adhesive between the opposing surfaces of adjacent wafer scale lenses, the position of the superimposed wafer scale lenses can be changed before bonding. That is, after correcting the position so as to satisfy the characteristics of the stacked wafer lens, the wafer scale lens can be bonded after being overlapped. Accordingly, there is no positional deviation or tilt between the wafer scale lenses.

  As described above, according to the above configuration, the distance between the wafer scale lenses is kept constant, and the positional deviation or the inclination between the wafer scale lenses does not occur. Therefore, it is possible to realize a laminated wafer lens in which wafer scale lenses are superimposed with high accuracy.

  In the laminated wafer lens, it is preferable that the groove is formed on any facing surface of the two wafer scale lenses adjacent to each other.

  According to the said structure, the groove | channel is formed in any opposing surface of an adjacent wafer scale lens. As a result, the bonding area becomes wider than when a groove is formed on one of the wafer scale lenses. Therefore, the adhesive strength can be increased.

  In the laminated wafer lens, it is preferable that grooves formed in each of the two wafer scale lenses adjacent to each other overlap each other.

  According to the said structure, the groove | channel is formed in any opposing surface of an adjacent wafer scale lens. Furthermore, the grooves formed on the opposing surfaces overlap each other, and the grooves are connected. Thereby, it is possible to simultaneously fill the overlapping grooves with the adhesive. Therefore, the adhesive filling process (filling time) can be shortened while widening the adhesive region to increase the adhesive strength.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims. That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

  For example, in the above-described example, an example has been described for the shape or material of the wafer scale lens, the shape of the groove, the array shape of the groove, and the number of laminated wafer scale lenses. However, the example is limited to this example. It is not something.

  In particular, the present invention can be suitably used for various electronic devices such as a camera-equipped mobile phone, a digital still camera, a security camera, or a camera for a mobile phone, a vehicle, or an interphone.

20 Laminated wafer lens 201, 202 Wafer scale lens 201a, 202a Lens optical part 201b, 202b Groove (groove)
203 Adhesive

Claims (6)

A wafer scale lens having a plurality of lens optical units is a laminated wafer lens in which a plurality of sheets are superimposed,
At least one of the two wafer scale lenses adjacent to each other has a groove connecting both ends of the opposing surface formed on the opposing surface of the other, avoiding the lens optical part,
Except for the portion where the groove is formed, the opposing surfaces of the two wafer scale lenses adjacent to each other are in contact with each other,
The groove is filled with an adhesive ,
The groove is formed on any facing surface of the two wafer scale lenses adjacent to each other.
The grooves formed in each of the two wafer scale lenses adjacent to each other overlap each other,
The opposing surfaces of the two wafer scale lenses adjacent to each other are in direct contact with each other except for the portion where the groove and the lens optical part are formed, and the contact parts are in surface contact with each other. Laminated wafer lens.   2. The laminated wafer lens according to claim 1, wherein the groove is formed so as to surround a lens optical part of the wafer scale lens. The laminated wafer lens according to claim 1 or 2 , wherein the groove is formed so as to include a cutting region for dividing the laminated wafer lens into individual multilayer lenses. 4. The laminated wafer lens according to claim 3 , wherein the groove is formed so as to be shared between adjacent multilayer lenses. Laminated wafer lens singulated multilayer lens according to any one of claims 1-4. It is a manufacturing method of a lamination type wafer lens given in any 1 paragraph of Claims 1-4 ,
A laminating process for superimposing a plurality of wafer scale lenses;
A position adjusting step for adjusting the position of the plurality of laminated wafer scale lenses;
Filled with an adhesive to the grooves, seen including a bonding step of bonding the wafer scale lens adjusted position,
In the above lamination process,
Overlapping grooves formed on any facing surface of two wafer scale lenses adjacent to each other,
The opposing surfaces of the two wafer scale lenses adjacent to each other are in direct contact with each other except for the portion where the groove and the lens optical part are formed, and the wafer scale lens is mounted so that the contact parts are in surface contact with each other. A method for manufacturing a laminated wafer lens, characterized by superposing them.

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