TWI613915B - Image sensor - Google Patents

Abstract

An image sensor includes a substrate, an image sensing element and an adhesive layer. The substrate has a curved surface. The image sensing element is disposed on an arc surface, and the image sensing element is curved along the arc surface. The adhesive layer is disposed on the arc surface and covers the image sensing element.

Description

Image sensor

The present invention relates to an image sensor, and more particularly, to an image sensor including a curved image sensor.

In recent years, due to the rapid development of multimedia technology, the use of digital images has become more frequent, and consumer demand for image processing devices has also increased. Many digital imaging products, such as web cameras, digital cameras, smart phones, etc., capture images using image sensors.

As for the complementary CMOS image sensing element, it can be designed to be curved to change its optical properties, thereby reducing the number of corresponding lenses required to achieve the small size of the image sensing module. Into. Generally speaking, the image sensing element that has not yet been bent is first placed on the arc surface of the substrate, and the arc surface of the substrate has a perforation located on the image sensing element, and then the image sensing is driven through the perforation through the perforation. The sensing element is bent downward and attached to the arc surface of the substrate, thereby obtaining a curved image sensing element. However, this method must first form a perforation for extraction on the substrate, which makes the manufacturing process more time-consuming and time-consuming, and the substrate is formed due to the perforation. Its structure is incomplete and cannot support the image sensing element stably, which may cause unexpected deformation of the image sensing element at the perforation. In addition, in general image sensing modules, the image sensing element is not covered with colloid, so it is easy for foreign matter (such as dust in the environment) to attach to the image sensing element during the manufacturing process and reduce image sensing. The quality of the module.

The invention provides an image sensor, which can save the manufacturing cost, can make its image sensing element be stably supported, and can prevent foreign objects from adhering to the image sensing element during the manufacturing process.

The image sensor of the present invention includes a substrate, an image sensing element and an adhesive layer. The substrate has a curved surface. The image sensing element is disposed on an arc surface, and the image sensing element is curved along the arc surface. The adhesive layer is disposed on the arc surface and covers the image sensing element.

Based on the above, in the image sensor of the present invention, in addition to the image sensing element disposed on the arc surface of the substrate, an adhesive layer for covering the image sensing element is further disposed. Therefore, in the process of laminating the image sensing element and the glue to the arc surface of the substrate, the image sensing element can be bent along the arc surface by pushing the glue layer on the image sensing element. Since the present invention does not bend the image sensing element by suction as described above, it is not necessary to form a perforation for suction at the curved surface of the substrate as in the conventional process, and the manufacturing process can be simplified to save manufacturing costs. In addition, since the substrate of the present invention does not need to be perforated as described above, the structure of the substrate is relatively complete and can stably support the image sensing element. Furthermore, by covering the image sensing element with an adhesive layer, foreign matter can be avoided during the manufacturing process. Is attached to the image sensing element.

In order to make the above features and advantages of the present invention more comprehensible, embodiments are hereinafter described in detail with reference to the accompanying drawings.

100, 200, 300, 400‧‧‧ image sensors

110, 210, 310, 410‧‧‧ substrate

110a, 210a, 310a, 410a

110b, 210b, 310b, 410b

120, 220, 320, 420, 520‧‧‧ image sensor

130, 230, 330, 330 ’, 430, 530’ ‧‧‧ adhesive layer

140, 340, 440, 540‧‧‧ Lid

150, 250, 350‧‧‧ conductive structure

152, 252, 352‧‧‧ conductive lines

154, 254, 354, 454‧‧‧ conductive vias

154a, 254a, 354a, 156, 256, 356, 456‧‧‧

160, 260, 360, 460, 560‧‧‧ conductive elements

A1, A2, A3 ‧‧‧ line segments

D‧‧‧ direction

E1, E2, E3, E4‧‧‧ end

H‧‧‧distance

h‧‧‧ height difference

R1, R2, R3, R4‧‧‧ flange

S1‧‧‧upside

S2‧‧‧ underside

T‧‧‧thickness

t1 ~ t7‧‧‧Time

FIG. 1A is a cross-sectional view of an image sensor according to an embodiment of the invention.

FIG. 1B is a partial plan view of the image sensor of FIG. 1A.

FIG. 2 is a cross-sectional view of an image sensor according to another embodiment of the present invention.

3A is a cross-sectional view of an image sensor according to another embodiment of the present invention.

3B to 3E are flowcharts of a method for manufacturing an image sensor according to an embodiment of the present invention.

FIG. 3F is a graph showing changes in environmental pressure, pressing force, and temperature in the manufacturing process of the image sensor of FIG. 3A.

FIG. 4 is a cross-sectional view of an image sensor according to another embodiment of the present invention.

FIG. 5 illustrates a cover, an adhesive layer, and an image sensing element according to another embodiment of the present invention.

FIG. 1A is a cross-sectional view of an image sensor according to an embodiment of the invention. Please refer to FIG. 1A. The image sensor 100 of this embodiment includes a substrate 110, an image sensing element 120, an adhesive layer 130, and a cover 140. The substrate 110 has a curved surface 110a, and the image sensing element 120 is disposed on the curved surface 110a of the substrate 110, so that image sensing is performed. The element 120 is curved in accordance with the curved surface 110 a of the substrate 110. The adhesive layer 130 is disposed on the arc surface 110 a of the substrate 110 to cover the image sensing element 120. The cover 140 is disposed on the substrate 110 to cover the image sensing element 120 and the adhesive layer 130. In this embodiment, the image sensing element 120 is, for example, a complementary metal-oxide-semiconductor image sensing element (CMOS image sensing element), but the present invention is not limited thereto.

Specifically, the substrate 110 in this embodiment has an upper side S1 and a lower side S2 opposite to each other. The curved surface 110a is located on the upper side S1 of the substrate 110. The curved surface 110a is a concave curved surface as shown in FIG. 1A and is formed on the substrate 110. A groove, the image sensing element 120 is disposed in the groove, the adhesive layer 130 is filled in the groove, and the curvature of the image sensing element 120 is the same as the curvature of the arc surface 110a. In other embodiments, the curved surface 110a may be a convex curved surface and the image sensing element 120 is disposed on the convex curved surface, which is not limited in the present invention.

As described above, in addition to the image sensing element 120, the adhesive layer 130 for covering the image sensing element 120 is disposed on the arc surface 110 a of the substrate 110. Therefore, in the process of pressing the image sensing element 120 and the adhesive layer 130 onto the arc surface 110a of the substrate 110, the image sensing element 120 can be pushed by the adhesive layer 130 to push the image sensing element 120. The curved surface 110a is curved. Since the image sensing element 120 is not bent by the extraction method as described above, it is not necessary to form a perforation for the extraction at the arc surface 110a of the substrate 110 as in the conventional manufacturing process, and the manufacturing process can be simplified to save manufacturing costs. . In addition, since the substrate 110 of this embodiment does not have a perforation at the arc surface 110 a as described above, the structure of the substrate 110 is relatively complete and can stably support the image sensing element 120. In addition, by covering the image sensing element 120 with the adhesive layer 130, it is possible to avoid No foreign matter is attached to the image sensing element 120 during the manufacturing process.

Please refer to FIG. 1A. The maximum distance H between the top surface of the image sensing element 120 and the cover 140 in this embodiment is, for example, smaller than the thickness T of the cover 140. For example, the distance H is, for example, 12.5 to 100 micrometers, and the thickness T is, for example, 200 to 1000 micrometers. The height difference h of the top surface of the image sensing element 120 in the vertical direction in FIG. 1A is, for example, greater than 12.5 micrometers, but the present invention is not limited thereto.

FIG. 1B is a partial plan view of the image sensor of FIG. 1A. To make the drawing clearer, the adhesive layer 130, the cover 140, and the conductive element 160 in FIG. 1A are not shown in FIG. 1B. Please refer to FIG. 1A and FIG. 1B. The substrate 110 in this embodiment has at least one row of glue grooves 110b (shown as multiple). The glue grooves 110b extend from the periphery of the image sensing element 120 to the edge of the arc surface 110a. The excess colloid generated during the formation of the glue layer 130 can be discharged through the glue discharge groove 110b. Specifically, the arc surface 110a of this embodiment has a plurality of flanges R1 surrounding the image sensing element 120, and these flanges R1 are arranged at intervals to form the glue discharge grooves 110b. In addition, the ends E1 of the flanges R1 constitute a positioning recessed portion around the image sensing element 120, so that the image sensing element 120 is positioned at the positioning recessed portion formed by the ends E1 of the flanges R1.

In this embodiment, the contour of the outer edge of the arc surface 110a is rectangular as shown in FIG. 1B, and the positioning recess formed by the ends E1 of the flanges R1 is rectangular as shown in FIG. 1B, but the present invention does not adopt this Limited. In other embodiments, the outer contour of the arc surface 110a may be circular or other suitable shapes, and the positioning recess formed by the ends E1 of the flanges R1 may be circular or other suitable shapes. In addition, in this embodiment, the arc surface 110a has radians only in the direction D, for example, but the present invention does not take this as an example. However, in other embodiments, the arc surface 110a may have arcs in other directions to form a bowl-shaped groove.

As shown in FIGS. 1A and 1B, the image sensor 100 includes a conductive structure 150. The conductive structure 150 is disposed on the substrate 110 and is electrically connected to the image sensing element 120, and extends from below the image sensing element 120 to an arc. Outside the surface 110a, the image sensing element 120 can transmit signals through the conductive structure 150. Specifically, the image sensor 100 includes at least one conductive element 160 (illustrated as two), and the conductive structure 150 includes at least one conductive line 152 (illustrated as two), and at least one conductive via 154 (illustrated) Two are, for example, TSVs) and at least one pad 156 (shown as two). The conductive element 160 is, for example, a conductive bump and is disposed between the image sensing element 120 and the arc surface 110a. The two conductive elements 160 are used to electrically connect the image sensing element 120 and are used to electrically connect the two pads of the conductive structure 150 respectively. 156. The two pads 156 are disposed on the arc surface 110 a and are respectively connected to two conductive lines 152. The two conductive lines 152 extend from the inside of the arc surface 110 a to the outside of the arc surface 110 a along the upper side S1 of the substrate 110 and are respectively connected to the two conductive vias 154. Each conductive via 154 is connected to the corresponding conductive line 152 through the pad 154 a on the upper side S1 of the substrate 110, and penetrates from the outside of the arc surface 110 a to the lower side S2 of the substrate 110. In this embodiment, each of the conductive lines 152 of the conductive structure 150 extends along the glue discharge groove 110b to the outside of the arc surface 110a, but the present invention is not limited thereto.

FIG. 2 is a cross-sectional view of an image sensor according to another embodiment of the present invention. In the embodiment shown in FIG. 2, the substrate 210, the curved surface 210a, the glue discharge groove 210b, the image sensing element 220, the adhesive layer 230, the conductive structure 250, the conductive line 252, the conductive via 254, The configuration and function of the contact pad 254a, the contact pad 256, the conductive element 260, the flange R2, and the end E2 are similar to the substrate 110, the curved surface 110a, the drainage groove 110b, the image sensing element 120, the adhesive layer 130, The configuration and function of the conductive structure 150, the conductive line 152, the conductive through hole 154, the contact pad 154a, the contact pad 156, the conductive element 160, the flange R1, and the end E1 are not repeated here. The difference between the image sensor 200 and the image sensor 100 is that the image sensor 200 is not configured as shown in FIG. 1A to cover the image sensor 120 and the cover 140 of the adhesive layer 130.

3A is a cross-sectional view of an image sensor according to another embodiment of the present invention. In the embodiment shown in FIG. 3A, the substrate 310, the curved surface 310a, the glue discharge groove 310b, the image sensing element 320, the adhesive layer 330, the cover 340, the conductive structure 350, the conductive line 352, the conductive through hole 354, The arrangement and function of the pad 354a, the pad 356, the conductive element 360, the flange R3, and the end E3 are similar to that of the substrate 110, the arc surface 110a, the drainage tank 110b, the image sensing element 120, the adhesive layer 130, and the cover in FIG. 1A. The configuration and function of the body 140, the conductive structure 150, the conductive circuit 152, the conductive through hole 154, the contact pad 154a, the contact pad 156, the conductive element 160, the flange R1, and the terminal E1 are not repeated here. The difference between the image sensor 300 and the image sensor 100 is that the conductive element 360 is not a conductive bump 160 as shown in FIG. 1A, and the conductive element 360 is an anisotropic conductive film (ACF). Due to its anisotropic conductive property, the two pads 356 are not electrically connected to each other, and the image sensing element 320 is electrically connected to the two pads 356 through the anisotropic conductive adhesive.

The image sensor 300 shown in FIG. 3A is taken as an example to describe a method for manufacturing the image sensor according to an embodiment of the present invention. 3B to 3E show an embodiment of the present invention. The flowchart of the manufacturing method of the example image sensor. First, as shown in FIG. 3B, a substrate 310 is provided. The substrate 310 has an arc surface 310a. Next, as shown in FIG. 3C, a cover 340, an adhesive layer 330 ′, and an image sensing element 320 are provided. The adhesive layer 330 ′ is, for example, a non-conductive film (NCF). limit. Then, as shown in FIG. 3D, the adhesive layer 330 'is bonded between the cover 340 and the image sensing element 320.

Finally, as shown in FIG. 3E, the combined cover 340, the adhesive layer 330 'and the image sensing element 320 are positioned on the substrate 310, and the cover 340, the adhesive layer 330' and the image sensing element 320 are pressed onto the substrate. 310 becomes the state shown in FIG. 3A, the image sensing element 320 is bent by the curved surface 310a of the substrate 310 by being pushed by the adhesive layer 330 ', and the adhesive layer 330 covers the image sensing element 320. In this process, the image sensing element 320 is bent so that the curvature of the image sensing element 320 is the same as the curvature of the arc surface 310a, and the positioning recess formed by the image sensing element 320 on the end E3 of the flange R3 is positioned so that The bottom surface of the image sensing element 320 is completely supported by the arc surface 310a. The conductive element 360 electrically connects the image sensing element 320 and the pad 356 of the conductive structure to each other, and fills the adhesive layer 330 in the groove of the substrate 310. The image sensing element 320 and the adhesive layer 330 are covered by a cover 340. In addition, after the cover 340, the adhesive layer 330, and the image sensing element 320 are pressed to the substrate 310, the cover 340 can be removed, which is not limited in the present invention. Among them, the adhesive layer of FIGS. 3C to 3E that has not been laminated is denoted by reference numeral 330 ', and the adhesive layer of FIG. 3A that has been laminated to fill the groove of the substrate 310 is denoted by reference numeral 330. In this embodiment, the material of the image sensing element 320 may include silicon. The thickness of the image sensing element 320 is, for example, less than 200 μm, and the image sensing The bonding temperature of the measuring element 320 is, for example, 100 to 200 ° C., but the invention is not limited thereto.

FIG. 3F is a graph showing changes in environmental pressure, pressing force, and temperature in the manufacturing process of the image sensor of FIG. 3A. In FIG. 3F, the vertical axes of the line segments A1, A2, and A3 represent the pressing force, the ambient pressure, and the temperature, respectively, and the horizontal axis is time. Please refer to FIG. 3F. In more detail, before pressing the cover 340, the adhesive layer 330, and the image sensing element 320 to the substrate 310, the working environment is brought into a vacuum state at time t1. Then, the cover 340, the adhesive layer 330 ', and the image sensing element 320 start to contact the substrate 310 at time t2, and gradually increase the pressing force. At time t3, the temperature is increased to heat the glue layer 330 'to melt it to fill the groove of the substrate 310, and to partially remove the melted glue layer 330' from the arc surface 310a along the glue discharge groove 310b. At time t4, the temperature is further increased to heat the conductive element 360 (anisotropic conductive adhesive) to melt it and be electrically connected to the image sensing element 320 and the conductive structure 350. At time t5, the working environment is returned from the vacuum state to the non-vacuum state. At time t6, the temperature is lowered to cool the molten glue layer 330 to solidify and cover the image sensing element 320. At time t7, the application of the pressing force is stopped to complete the production of the image sensor 300.

FIG. 4 is a cross-sectional view of an image sensor according to another embodiment of the present invention. In the embodiment shown in FIG. 4, the substrate 410, the curved surface 410a, the glue discharge groove 410b, the image sensing element 420, the adhesive layer 430, the cover 440, the pad 456, the conductive element 460, the flange R4, and the end E4 The configuration and function are similar to the substrate 110, the curved surface 110a, the discharge tank 110b, the image sensing element 120, the adhesive layer 130, the cover 140, the pad 156, the conductive element 160, the flange R1, and the end E1 in FIG. 1A. Configuration and function, in This will not be repeated here. The difference between the image sensor 400 and the image sensor 100 is that the two conductive vias 454 of the conductive structure are directly connected to the two pads 456 and penetrate from the arc surface 410a to the lower side of the substrate 410. However, the present invention does not This is the limit.

FIG. 5 illustrates a cover, an adhesive layer, and an image sensing element according to another embodiment of the present invention. The cover 540, the adhesive layer 530 ', the image sensing element 520, and the conductive element 560 shown in FIG. 5 are configured and function similarly to the cover 340, the adhesive layer 330', the image sensing element 320, and the conductive element 360 of FIG. 3D. The configuration and function mode are not repeated here. The embodiment shown in FIG. 5 is different from the embodiment shown in FIG. 3D in that the adhesive layer 530 'which has not been laminated to the substrate has a convex portion 532 corresponding to the image sensing element 520, so that the convex portion 532 can be more reliably The image sensing element 520 is pressed onto the substrate.

In summary, in the image sensor of the present invention, in addition to the image sensing element disposed on the curved surface of the substrate, an adhesive layer is disposed to cover the image sensing element. Therefore, in the process of laminating the image sensing element and the glue to the arc surface of the substrate, the image sensing element can be bent along the arc surface by pushing the glue layer on the image sensing element. Since the present invention does not bend the image sensing element by suction as described above, it is not necessary to form a perforation for suction at the curved surface of the substrate as in the conventional process, and the manufacturing process can be simplified to save manufacturing costs. In addition, since the substrate of the present invention does not need to be perforated as described above, the structure of the substrate is relatively complete and can stably support the image sensing element. Furthermore, by covering the image sensing element with an adhesive layer, foreign matter can be prevented from adhering to the image sensing element during the manufacturing process.

Although the present invention has been disclosed as above with the examples, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field will not depart from the present invention. Within the spirit and scope, some modifications and retouching can be made. Therefore, the scope of protection of the present invention shall be determined by the scope of the attached patent application.

200‧‧‧Image Sensor

210‧‧‧ substrate

210a‧‧‧arc

210b‧‧‧Draining tank

220‧‧‧Image sensor

230‧‧‧ Adhesive layer

250‧‧‧ conductive structure

252‧‧‧ conductive line

254‧‧‧ conductive via

254a, 256‧‧‧ pad

260‧‧‧ conductive element

E2‧‧‧End

R2‧‧‧ flange

Claims (14)

An image sensor includes: a substrate having a curved surface, wherein the curved surface is a concave curved surface to form a groove on the substrate; an image sensing element is disposed on the curved surface, and the image The sensing element is curved along the curved surface; and an adhesive layer is disposed on the curved surface and covers the image sensing element, wherein the adhesive layer is filled in the groove. The image sensor according to item 1 of the scope of patent application, wherein the curvature of the image sensing element is the same as the curvature of the arc surface. The image sensor according to item 1 of the patent application scope includes a cover, wherein the cover is disposed on the substrate and covers the image sensing element and the adhesive layer. The image sensor according to item 3 of the scope of patent application, wherein a maximum distance between a top surface of the image sensing element and the cover is smaller than a thickness of the cover. The image sensor according to item 1 of the patent application scope, wherein the substrate has no perforation at the arc surface. The image sensor according to item 1 of the patent application scope, wherein the substrate has at least one row of glue grooves extending from a peripheral edge of the image sensing element to an edge of the arc surface. The image sensor according to item 6 of the patent application, wherein the number of the at least one row of rubber grooves is plural, and the arc surface has a plurality of flanges surrounding the image sensing element, and the flanges are spaced apart. They are arranged to form the glue discharging grooves. The image sensor according to item 7 of the scope of patent application, wherein the ends of the flanges surround the image sensing element to form a positioning recess, and the image sensing element is positioned at the positioning recess. The image sensor according to item 1 of the patent application scope includes a conductive structure, wherein the conductive structure is disposed on the substrate and is electrically connected to the image sensing element, and extends from below the image sensing element to Outside the arc. The image sensor according to item 9 of the patent application scope, wherein the substrate has an upper side and a lower side opposite to each other, the curved surface is located on the upper side of the substrate, and the conductive structure is from inside the curved surface or outside the curved surface Penetrates to the lower side of the substrate. The image sensor according to item 9 of the application, wherein the conductive structure includes at least one of a conductive via and a conductive circuit. The image sensor according to item 9 of the scope of patent application, comprising at least one conductive element, wherein the conductive element is disposed between the image sensing element and the arc surface, and is electrically connected to the image sensing element and the Conductive structure. The image sensor according to item 12 of the application, wherein the conductive element is a conductive bump or an anisotropic conductive adhesive. The image sensor according to item 6 of the patent application scope includes a conductive structure, wherein the conductive structure extends along the rubber discharge groove to the outside of the arc surface.