TWI898841B - Wafer-level manufacturing method for stereoscopic camera module and stereoscopic camera module - Google Patents

Abstract

A wafer-level manufacturing method for stereoscopic camera module including: forming a plurality of image sensors on a first substrate. Forming a plurality of lenses on a second substrate. Aligning, stacking and cutting the first substrate and the second substrate, and then packaging them to form a plurality of image sensor modules. Combining two of the image sensor modules to form a stereoscopic camera module. One of the image sensor modules of the stereoscopic camera module is disposed on one side of a baseline, and a central axis of a sensing surface of the image sensor, relative to an optical axis of the lens, is shifted toward a direction away from the one side. The other one of the image sensor modules of the stereoscopic camera module is disposed on other one side of the baseline, and a central axis of a sensing surface of the image sensor, relative to an optical axis of the lens, is shifted toward a direction away from the other one side. A stereoscopic camera module is also provided.

Description

Wafer-level manufacturing method for stereoscopic imaging module and stereoscopic imaging module

The present invention relates to a wafer-level manufacturing method and a camera module, and in particular to a wafer-level manufacturing method for a stereoscopic camera module and a stereoscopic camera module.

Existing 3D camera display technology uses two parallel cameras, one on the left and one on the right, with the optical center of each camera aligned with the center of the photosensitive element. However, the 3D camera structure of this system cannot produce content with positive parallax, that is, it cannot produce 3D content with depth behind the screen.

The present invention provides a wafer-level manufacturing method for a stereoscopic imaging module and a stereoscopic imaging module, wherein the stereoscopic imaging module can generate stereoscopic images with positive and negative parallax.

One embodiment of the present invention provides a wafer-level manufacturing method for a stereoscopic camera module, which includes the following steps. A plurality of image sensors are formed on a first substrate. A plurality of lenses are formed on a second substrate. The first substrate and the second substrate are aligned, stacked, and cut, and then packaged to form a plurality of image sensor modules, wherein the optical axis of the lens in each image sensor module is parallel to but does not overlap with the center axis of the sensing surface of the image sensor. Two of the image sensor modules are combined into a stereoscopic camera module, wherein in one of the image sensor modules of the stereoscopic camera module, the one of the image sensor modules is arranged on one side of the baseline, and the center axis of the sensing surface of the image sensor is offset in a direction away from the optical axis of the lens. In the other image sensor module of the stereo camera module, the other image sensor module is disposed on the other side of the baseline, and the center axis of the sensing surface of the image sensor is offset away from the other side relative to the optical axis of the lens. The line connecting the center of the sensing surface of the one image sensor module and the center of the sensing surface of the other image sensor module defines the baseline.

One embodiment of the present invention provides a stereoscopic camera module, which includes a first carrier substrate, a first image sensor, a first lens, a second carrier substrate, a second image sensor and a second lens. The first image sensor is arranged on the first carrier substrate and is arranged on one side of a baseline. The first lens is stacked on the first image sensor, wherein the center axis of the sensing surface of the first image sensor is offset in a direction away from the side relative to the optical axis of the first lens. The second image sensor is arranged on the second carrier substrate and is arranged on the other side of the baseline. The second lens is stacked on the second image sensor, wherein the center axis of the sensing surface of the second image sensor is offset in a direction away from the other side relative to the optical axis of the second lens. The line connecting the center of the sensing surface of the first image sensor and the center of the sensing surface of the second image sensor defines the baseline.

Based on the above, in the wafer-level manufacturing method for a stereoscopic imaging module and the stereoscopic imaging module of the embodiments of the present invention, the center axes of the image sensor's sensing surface are offset during the image sensor formation process or during alignment, stacking, and cutting. Furthermore, when assembling the stereoscopic imaging module, the center axes of the sensing surfaces of the two image sensors are offset in opposite directions. Therefore, the embodiments of the present invention can manufacture a wafer-level stereoscopic imaging module that can capture stereoscopic images with positive and negative parallax.

FIG1 is a schematic diagram of a stereoscopic camera module according to one embodiment of the present invention. Referring to FIG1 , one embodiment of the present invention provides a stereoscopic camera module 10 comprising a first substrate 120, a first image sensor 140, a first lens 160, a second substrate 220, a second image sensor 240, and a second lens 260.

In this embodiment, the first carrier substrate 120 may be a portion of a wafer substrate, and its material may be, for example, silicon, gallium nitride, or silicon carbide. The second carrier substrate 220 may be a portion of a glass substrate. The first image sensor 140 and the second image sensor 240 may be complementary metal-oxide semiconductor (CMOS) image sensors or charge coupled device (CCD) image sensors, but the present invention is not limited thereto. The first lens 160 and the second lens 260 may, for example, comprise a combination of one or more optical lenses having a refractive power, such as various combinations of non-planar lenses, including biconcave lenses, biconvex lenses, concave-convex lenses, convex-concave lenses, plano-convex lenses, and plano-concave lenses.

In this embodiment, first image sensor 140 is disposed on first carrier substrate 120 and is positioned on one side of baseline B. First lens 160 is stacked on first image sensor 140, wherein central axis 140C of the sensing surface of first image sensor 140 is offset away from the side relative to optical axis 160C of first lens 160 (for example, FIG1 illustrates an offset to the left). Second image sensor 240 is disposed on second carrier substrate 220 and is positioned on the other side of baseline B. Second lens 260 is stacked on second image sensor 240, wherein central axis 240C of the sensing surface of second image sensor 240 is offset away from the other side relative to optical axis 260C of second lens 260 (for example, FIG1 illustrates an offset to the right). The line connecting the center C1 of the sensing surface of the first image sensor 140 and the center C2 of the sensing surface of the second image sensor 240 defines a baseline B.

In this embodiment, the optical axis 160C of the first lens 160 passes through the center C3 of the first carrier substrate 120 , and the optical axis 260C of the second lens 260 passes through the center C4 of the second carrier substrate 220 .

Furthermore, in this embodiment, the offset S of the central axis 140C of the first image sensor 140 and the offset S of the central axis 240C of the second image sensor 240 are designed based on factors such as parallax correction, the length of baseline B, viewing distance, and visual radiation adjustment conflicts. For example, the offset is designed to be 25 pixels/28 μm.

Figure 2 is a schematic diagram of the manufacturing process of the stereoscopic camera module of Figure 1. Figure 3A is a flow chart of the manufacturing method of the stereoscopic camera module of Figure 1. Referring to Figures 2 and 3A, one embodiment of the present invention provides a wafer-level manufacturing method for a stereoscopic camera module 10, comprising the following steps. In step S100, as shown in Figure 2, a plurality of image sensors 340 are formed on a first substrate SUB1. In step S200, a plurality of lenses 360 are formed on a second substrate SUB2. In step S300, the first substrate SUB1 and the second substrate SUB2 are aligned, stacked, and cut, and then packaged to form a plurality of image sensor modules 300. In each image sensor module 300, the optical axis 360C of the lens 360 and the central axis 340C of the sensing surface of the image sensor 340 are parallel to each other but do not overlap. In step S400, two of the image sensor modules 300 are assembled into a stereoscopic camera module 10. As shown in FIG1 , one of the image sensor modules 100 in the stereoscopic camera module 10 is positioned on one side of a baseline B, and the center axis 140C of the sensing surface of the image sensor 140 is offset away from the baseline B relative to the optical axis 160C of the lens 160. The other image sensor module 200 in the stereoscopic camera module 10 is positioned on the other side of the baseline B, and the center axis 240C of the sensing surface of the image sensor 240 is offset away from the other side relative to the optical axis 260C of the lens 260. A line connecting the center C1 of the sensing surface of one of the image sensor modules 100 and the center C2 of the sensing surface of the other image sensor module 200 defines a baseline B.

FIG3B and FIG3C are detailed flow charts of step S100 and step S400 in FIG3A , respectively. Referring to FIG3B and FIG3C , in this embodiment, the aforementioned step S100 includes the following steps. Step S120 is to shift the center axis 340C of the sensing surface of each image sensor 340 relative to the center C3/C4 of the range to be cut R on the first substrate SUB1 in an offset direction (for example, FIG2 illustrates a shift to the left). When the first substrate SUB1 is cut, the substrate within the range to be cut R forms the first carrier substrate 120 and the second carrier substrate 220 of FIG1 . When the second substrate SUB2 is cut, the substrate within the range to be cut R forms the carrier substrate of the first lens 160 and the second lens 260 of FIG1 .

In this embodiment, step S400 includes the following steps. In step S420, one of the two image sensor modules 300 is rotated 180 degrees (relative to the optical axis 260C of its lens 260). In other words, in step S120, the image sensors 340 are offset by a certain distance using semiconductor processing technology. Therefore, after stacking and dicing, each image sensor 340 is offset simultaneously and by the same offset amount S. Finally, one of the image sensor modules 200 is rotated 180 degrees and reassembled to complete the left and right image sensor modules 100, 200, each with the same offset amount S but different offset directions.

Based on the above, in one embodiment of the present invention, a wafer-level manufacturing method for a stereoscopic camera module 10 and the stereoscopic camera module 10 offset the center axis 340C of the sensing surface of the image sensor 340 during the formation of the image sensor 340 or during alignment, stacking, and cutting. Furthermore, when assembling the stereoscopic camera module 10, the center axes 140C and 240C of the sensing surfaces of the two image sensors 140 and 240 are offset in opposite directions. Therefore, this embodiment of the present invention can manufacture a wafer-level stereoscopic camera module 10 that can capture stereoscopic images with positive and negative parallax.

FIG4 is a schematic diagram of a stereoscopic camera module according to an embodiment of the present invention. Referring to FIG4 , stereoscopic camera module 10A is similar to stereoscopic camera module 10 of FIG1 , with the primary difference being that image sensor module 200 does not need to be rotated 180 degrees during assembly of stereoscopic camera module 10A.

Figure 5 is a schematic diagram illustrating the manufacturing process of the stereoscopic camera module of Figure 4. Figures 6A and 6B are detailed flow charts of the manufacturing method of the stereoscopic camera module of Figure 4, corresponding to steps S100 and S400 in Figure 3A, respectively. Referring to Figures 5 to 6B, step S100 includes the following steps. In step S120A, within a portion of image sensors 340-1 and 340-2, the center axis 340-1C of the sensing surface of each image sensor 340-1 is offset in an offset direction relative to the center C3 of the area to be cut R on the first substrate SUB1 (for example, to the left as shown in FIG5 ). Furthermore, within another portion of image sensors 340-1 and 340-2, the center axis 340-2C of the sensing surface of each image sensor 340-2 is offset opposite to the offset direction relative to the center C3 of the area to be cut R on the first substrate SUB1 (for example, to the right as shown in FIG5 ). The aforementioned portion or the other portion of image sensors 340-1 and 340-2 may be, for example, half the number of image sensors 340-1 and 340-2, but the present invention is not limited thereto.

In this embodiment, step S400 includes the following steps. In step S420A, an image sensor module 300 is selected from among the image sensor modules 300, one whose image sensor 340-1 is offset in the offset direction, and one whose image sensor 340-2 is offset away from the offset direction, to form the stereoscopic imaging module 10A. In other words, during the formation of the image sensors 300, half of the image sensors 300 can be offset in the offset direction, while the other half can be offset away from the offset direction. Therefore, when assembling the stereoscopic imaging module 10A, the image sensors 100 and 200 can be directly assembled without rotating the image sensor 200 180 degrees.

FIG7 is a schematic diagram of a stereoscopic imaging module according to an embodiment of the present invention. Referring to FIG7 , stereoscopic imaging module 10B is similar to stereoscopic imaging module 10 of FIG1 , with the primary difference being that, in this embodiment, the central axis 140C of the sensing surface of first image sensor 140 passes through the center C1 of first substrate 120, and the central axis 240C of the sensing surface of second image sensor 240 passes through the center C2 of second substrate 220 (however, the optical axis 160C of first lens 160 does not pass through the center C1 of first substrate 120, and the optical axis 260C of second lens 260 does not pass through the center C2 of second substrate 220).

Figures 8A and 8B are schematic diagrams illustrating the manufacturing process of the stereoscopic camera module of Figure 7. Figures 9A and 9B are detailed flow charts corresponding to steps S300 and S400 in Figure 3A, respectively, of the manufacturing method of the stereoscopic camera module of Figure 7. Referring to Figures 8A and 9B, in this embodiment, the first substrate SUB1 includes a first sub-substrate SUB1-1 and a second sub-substrate SUB1-2, and the second substrate SUB2 includes a third sub-substrate SUB2-1 and a fourth sub-substrate SUB2-2.

In this embodiment, step S300 includes the following steps: Step S320B, as shown in FIG8A , aligns, stacks, and cuts the first sub-substrate SUB1-1 and the third sub-substrate SUB2-1, and then packages them. During the alignment process, the center axis 340C of the sensing surface of each image sensor 340 on the first sub-substrate SUB1-1 is offset relative to the optical axis 360C of the lens 360 on the aligned third sub-substrate SUB2-1 in an offset direction (for example, to the left in FIG8A ), where the center axis 340C passes through the center C3 of the to-be-cut range R on the first sub-substrate SUB1-1. In step S340B, as shown in FIG8B , the second sub-substrate SUB1-2 and the fourth sub-substrate SUB2-2 are aligned, stacked, and cut, and then packaged. During the alignment process, the center axis 340C of the sensing surface of each image sensor 340 on the second sub-substrate SUB1-2 is offset relative to the optical axis 360C of the lens 360 on the aligned fourth sub-substrate SUB2-2 in the opposite direction of the offset direction (for example, FIG8B shows an offset to the right), wherein the center axis 340C passes through the center C4 of the range R to be cut on the second sub-substrate SUB2-2.

Furthermore, in this embodiment, step S400 includes the following step: Step S420B, wherein an image sensor module 300 whose image sensor 340 is offset in the offset direction and another image sensor module 300 whose image sensor 340 is offset away from the offset direction are selected from the image sensor modules 300 to form a stereoscopic imaging module 10B. In other words, compared to the stereoscopic imaging modules 10 and 10A, which employ an offsetting method for the sensing surface of the image sensor 340 during the manufacturing process, the stereoscopic imaging module 10B achieves the same effect by offsetting the entire substrate during alignment. In a preferred embodiment, a packaging component can be installed on the outside of the image sensor modules 100, 200 to reinforce the overall structure; or, during the alignment process, a positioning mechanism can be added to assist in positioning.

FIG10 is a schematic diagram of a stereoscopic camera module according to an embodiment of the present invention. Referring to FIG10 , stereoscopic camera module 10C is similar to stereoscopic camera module 10B of FIG7 , with the primary difference being that during assembly of stereoscopic camera module 10C, image sensor module 200 does not need to be rotated 180 degrees.

FIG11 is a schematic diagram of the manufacturing process of the stereoscopic camera module of FIG10 . FIG12A and FIG12B are detailed flow charts corresponding to step S300 and step S400 in FIG3A , respectively, in the manufacturing method of the stereoscopic camera module of FIG10 . Referring to FIG11 and FIG12 , the aforementioned step S300 includes the following steps. Step S320C, during the alignment process, shifts the center axis 340C of the sensing surface of each image sensor 340 on the first substrate SUB1 relative to the optical axis 360C of the lens 360 on the second substrate SUB2 aligned therewith in an offset direction (for example, FIG11 illustrates a leftward offset), wherein the center axis 340C passes through the center C3/C4 of the range R to be cut on the first substrate SUB1.

In this embodiment, the above step S400 includes the following steps: Step S420C, rotating one of the two image sensor modules 300 by 180 degrees. For example, FIG10 illustrates the image sensor module 200 being rotated by 180 degrees relative to the optical axis 260C of the lens 260.

In summary, in embodiments of the present invention, a wafer-level manufacturing method for a stereoscopic imaging module and a stereoscopic imaging module offset the central axis of the image sensor's sensing surface during the image sensor formation process or during alignment, stacking, and cutting. Furthermore, when the stereoscopic imaging module is assembled, the central axes of the sensing surfaces of the two image sensors are offset in opposite directions. Therefore, embodiments of the present invention can produce a wafer-level stereoscopic imaging module capable of capturing stereoscopic images with positive and negative parallax.

10, 10A, 10B, 10C: Stereo camera module 100, 200, 300: Image sensor module 120: First carrier substrate 140: First image sensor 140C, 240C, 340C, 340-1C, 340-2C: Center axis 160: First lens 160C, 260C, 360C: Optical axis 220: Second carrier substrate 240: Second image sensor 260: Second lens 340, 340-1, 340-2: Image sensor 360: Lens B: Baseline C1, C2, C3, C4: Center R: Range to be cut S: Offset S100, S120, S120A, S200, S300, S320B, S340B, S400, S420, S420A, S420B, S420C: Steps SUB1: First substrate SUB1-1: First sub-substrate SUB1-2: Second sub-substrate SUB2: Second substrate SUB2-1: Third sub-substrate SUB2-2: Fourth sub-substrate

Figure 1 is a schematic diagram of a stereoscopic imaging module according to an embodiment of the present invention. Figure 2 is a schematic diagram of the manufacturing process of the stereoscopic imaging module of Figure 1. Figure 3A is a flow chart of a method for manufacturing the stereoscopic imaging module of Figure 1. Figures 3B and 3C are detailed flow charts of steps S100 and S400, respectively, in Figure 3A. Figure 4 is a schematic diagram of a stereoscopic imaging module according to an embodiment of the present invention. Figure 5 is a schematic diagram of the manufacturing process of the stereoscopic imaging module of Figure 4. Figures 6A and 6B are detailed flow charts of the method for manufacturing the stereoscopic imaging module of Figure 4 corresponding to steps S100 and S400, respectively, in Figure 3A. Figure 7 is a schematic diagram of a stereoscopic imaging module according to an embodiment of the present invention. Figures 8A and 8B are schematic diagrams illustrating the manufacturing process of the stereoscopic imaging module of Figure 7. Figures 9A and 9B are detailed flow charts corresponding to steps S300 and S400 in Figure 3A, respectively, of the method for manufacturing the stereoscopic imaging module of Figure 7. Figure 10 is a schematic diagram of a stereoscopic imaging module according to an embodiment of the present invention. Figure 11 is a schematic diagram illustrating the manufacturing process of the stereoscopic imaging module of Figure 10. Figures 12A and 12B are detailed flow charts corresponding to steps S300 and S400 in Figure 3A, respectively, of the method for manufacturing the stereoscopic imaging module of Figure 10.

S100, S200, S300, S400: Steps

Claims (12)

A wafer-level manufacturing method for a stereoscopic camera module comprises: forming a plurality of image sensors on a first substrate; forming a plurality of lenses on a second substrate; aligning, stacking, and cutting the first and second substrates, and then packaging them to form a plurality of image sensor modules, wherein the optical axis of the lens in each image sensor module is parallel to, but does not overlap, the central axis of the sensing surface of the image sensor; and Two of the image sensor modules are assembled into the stereoscopic imaging module. In one of the image sensor modules of the stereoscopic imaging module, the image sensor module is disposed on one side of a baseline, and the central axis of the sensing surface of the image sensor is offset away from the side relative to the optical axis of the lens. In the other of the image sensor modules of the stereoscopic imaging module, the other of the image sensor modules is disposed on the other side of the baseline, and the central axis of the sensing surface of the image sensor is offset away from the other side relative to the optical axis of the lens. The line connecting the center of the sensing surface of the one image sensor module and the center of the sensing surface of the other image sensor module defines the baseline. The wafer-level manufacturing method for a stereoscopic camera module as described in claim 1, wherein the step of forming the image sensors on the first substrate includes the following step: Offsetting the central axis of the sensing surface of each image sensor in an offset direction relative to the center of the to-be-cut range on the first substrate. The wafer-level manufacturing method for a stereoscopic camera module as described in claim 2, wherein the step of combining the two image sensor modules into the stereoscopic camera module includes the following steps: Rotating one of the two image sensor modules 180 degrees. The wafer-level manufacturing method for a stereoscopic camera module as described in claim 1, wherein the step of forming the image sensors on the first substrate includes the following steps: In a portion of the image sensors, the central axis of the sensing surface of each image sensor is offset in an offset direction relative to the center of the area to be cut on the first substrate; and in another portion of the image sensors, the central axis of the sensing surface of each image sensor is offset opposite to the offset direction relative to the center of the area to be cut on the first substrate. The wafer-level manufacturing method for a stereoscopic camera module as described in claim 4, wherein the step of combining the two of the image sensor modules into the stereoscopic camera module comprises the following steps: Selecting an image sensor module whose image sensor is offset in the offset direction and an image sensor module whose image sensor is offset opposite to the offset direction from the image sensor modules to form the stereoscopic camera module. The wafer-level manufacturing method for a stereoscopic camera module as described in claim 1, wherein the first substrate comprises a first sub-substrate and a second sub-substrate, and the second substrate comprises a third sub-substrate and a fourth sub-substrate, and the steps of aligning, stacking, and cutting the first and second substrates, and then packaging them to form the image sensor modules include the following steps: Aligning, stacking, and cutting the first and third sub-substrates, and then packaging them, and during the alignment process, offsetting the central axis of the sensing surface of each image sensor on the first sub-substrate relative to the optical axis of the lens on the aligned third sub-substrate in an offset direction, wherein the central axis passes through the center of the area to be cut on the first sub-substrate; and The second and fourth sub-substrates are aligned, stacked, and cut before packaging. During the alignment process, the central axis of the sensing surface of each image sensor on the second sub-substrate is offset opposite the offset direction relative to the optical axis of the lens on the aligned fourth sub-substrate, with the central axis passing through the center of the area to be cut on the second sub-substrate. The wafer-level manufacturing method for a stereoscopic camera module as described in claim 6, wherein the step of combining the two of the image sensor modules into the stereoscopic camera module comprises the following steps: Selecting an image sensor module whose image sensor is offset in the offset direction and an image sensor module whose image sensor is offset opposite to the offset direction from the image sensor modules to form the stereoscopic camera module. The wafer-level manufacturing method for a stereoscopic camera module as described in claim 1, wherein the steps of aligning, stacking, and cutting the first and second substrates, and then packaging them to form the image sensor modules, include the following steps: During the alignment process, the central axis of the sensing surface of each image sensor on the first substrate is offset relative to the optical axis of the lens on the second substrate to which it is aligned, in an offset direction, wherein the central axis passes through the center of the area to be cut on the first substrate. The wafer-level manufacturing method for a stereoscopic camera module as described in claim 8, wherein the step of combining the two image sensor modules into the stereoscopic camera module includes the following steps: Rotating one of the two image sensor modules 180 degrees. A stereoscopic camera module comprises: a first carrier substrate; a first image sensor disposed on the first carrier substrate and disposed on one side of a baseline; a first lens stacked on the first image sensor, wherein the center axis of the sensing surface of the first image sensor is offset away from the side relative to the optical axis of the first lens; a second carrier substrate; a second image sensor disposed on the second carrier substrate and disposed on the other side of the baseline; and a second lens stacked on the second image sensor, wherein the center axis of the sensing surface of the second image sensor is offset away from the other side relative to the optical axis of the second lens. The line connecting the center of the sensing surface of the first image sensor and the center of the sensing surface of the second image sensor defines the baseline. A stereoscopic camera module as described in claim 10, wherein the optical axis of the first lens passes through the center of the first supporting substrate, and the optical axis of the second lens passes through the center of the second supporting substrate. A stereoscopic camera module as described in claim 10, wherein the central axis of the sensing surface of the first image sensor passes through the center of the first supporting substrate, and the central axis of the sensing surface of the second image sensor passes through the center of the second supporting substrate.