JP2005243960A - Solid state image sensor and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a solid state sensor which can easily form a curve corresponding to a field curvature generated on an acceptance surface caused by optical system aberration. <P>SOLUTION: This method provides a concave at the opposite side of the acceptance surface and adheres a seat on that side by the use of a vacuum, mechanical stress or compressed air or by injecting the adhesive into the concave for hardening so that the curved solid state sensor can be easily manufactured. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a solid-state imaging device such as a CCD and a CMOS and a manufacturing method thereof.

  A conventional solid-state imaging device and manufacturing method will be described with reference to FIG. FIG. 5 is a cross-sectional view showing a schematic configuration of a conventional solid-state imaging device. In FIG. 5, a spherical curved surface 20 corresponding to the curvature of field caused by the aberration of the imaging lens of the imaging optical system is formed on the back surface of the semiconductor bare chip 19 mounted on the wiring board 18. A solid-state imaging device has been configured by pasting the solid-state imaging element 21 along the curved surface shape. (For example, see Patent Document 1)

  According to the present invention, the solid-state imaging device can be reduced in size, and the aberration caused by the imaging lens of the imaging optical system can be corrected, so that a solid-state imaging device focused on the entire screen was obtained.

JP 2003-188366 A

However, such a manufacturing method of a solid-state imaging device has a problem that it is very difficult such as a cutting process or a dry etching process in which the back surface of the semiconductor bare chip is curved. In addition, since the solid-state imaging device is thin, handling is inconvenient. Furthermore, there is a problem that the alignment of the semiconductor bare chip and the solid-state image sensor and the bonding of the back surface of the semiconductor bare chip and the back surface of the solid-state image sensor with compressed air are complicated processes.
The present invention proposes a manufacturing method that solves the above problems and easily forms a curved shape on the light receiving surface of a solid-state imaging device.

  The present invention provides a method for manufacturing a solid-state imaging device in which a curvature corresponding to curvature of field caused by an aberration of an optical system is formed on a light receiving surface, and a concave portion is provided on the opposite surface of the light receiving surface, and the opposite surface of the light receiving surface is formed in a vacuum. A method for manufacturing a solid-state imaging device in which a pedestal is bonded is used.

  The present invention relates to a method of manufacturing a solid-state imaging device in which a curvature corresponding to curvature of field caused by aberration of an optical system is formed on a light receiving surface, and a concave portion is provided on the opposite surface of the light receiving surface, and mechanical stress or compressed air is applied from the light receiving surface. Then, after forming a curved shape, a manufacturing method of a solid-state imaging device in which a pedestal is bonded to the opposite surface of the light receiving surface.

  The present invention relates to a method of manufacturing a solid-state imaging device in which a curvature corresponding to curvature of field caused by aberration of an optical system is formed on a light receiving surface, and a concave portion is provided on the opposite surface of the light receiving surface, and mechanical stress or compressed air is applied from the light receiving surface. To form a curved shape, inject an adhesive into this space, and cure the adhesive.

  According to the manufacturing method of the first aspect, since the concave portion is provided on the opposite surface of the light receiving surface and the pedestal is bonded to the opposite surface of the light receiving surface in a vacuum, a solid-state imaging device having a curved shape can be easily manufactured. Further, since the curved shape can be formed without directly touching the light receiving surface, the light receiving surface is not damaged. Furthermore, a desired curved shape can be obtained by changing the thickness of the light receiving surface. A desired curved shape can also be obtained by changing the pressure in vacuum.

  According to the manufacturing method of claim 2, the concave portion is provided on the opposite surface of the light receiving surface, and a pedestal is bonded to the opposite surface of the light receiving surface after forming a curved shape by applying mechanical stress or compressed air from the light receiving surface. A solid-state imaging device having a curved shape can be easily manufactured. Furthermore, a desired curved shape can be obtained by changing the thickness of the light receiving surface. A desired curved shape can also be obtained by changing mechanical stress or compressed air pressure when the light receiving surface is pressed.

  According to the manufacturing method of claim 3, a concave portion is provided on the opposite surface of the light receiving surface, a curved shape is formed by applying mechanical stress or compressed air from the light receiving surface, and an adhesive is put into this space to cure the adhesive. Therefore, a solid-state imaging device having a curved shape can be easily manufactured. Further, since the curved shape is fixed with an adhesive, the curved shape can be maintained even if there is a large pressure change on the light receiving surface. Further, a desired curved shape can be obtained by changing the thickness of the light receiving surface. A desired curved shape can also be obtained by changing mechanical stress or compressed air pressure when the light receiving surface is pressed.

  The best mode for carrying out the present invention will be described. According to the manufacturing method of the present invention, a recess is provided on the opposite surface of the light receiving surface, and a base is bonded to the opposite surface of the light receiving surface using vacuum, mechanical stress or compressed air, or an adhesive is injected into the recess. Therefore, a solid-state imaging device having a curved shape can be easily manufactured.

  A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view illustrating a manufacturing process of a solid-state imaging device. FIG. 4 is a perspective view of a solid-state image sensor bare chip. 4 in FIG. 4 indicates a light receiving element area. 2 in FIG. 1A is a solid-state image sensor bare chip before processing. Reference numeral 3 in FIG. 1B denotes a solid-state image sensor bare chip after processing the opposite surface of the light receiving surface into a concave portion by etching or cutting to a thickness that can form a desired curved shape. However, the thickness of the light receiving surface is set to a thickness that does not affect imaging even if it is influenced by atmospheric pressure of about 1100 hpa to 500 hpa. The size of the concave portion of the solid-state image pickup element bare chip 3 after processing shown in FIG. 1B may be larger than that of the light receiving element area 1 shown in FIG. Reference numeral 4 in FIG. 1C denotes a pedestal on which the solid-state image sensor is mounted. FIG. 1D shows the completed solid-state imaging device.

  In FIG. 1 (b), the processed solid-state image sensor bare chip 3 is placed in a vacuum furnace, and the pedestal 4 is bonded to the opposite surface of the light receiving surface as shown in FIG. 1 (c) so that the confidentiality of the recessed space 5 can be maintained. To do. At this time, the vacuum pressure is adjusted so that a desired curved shape is obtained after completion. Next, with the solid-state imaging device bare chip 3 and the pedestal 4 bonded, by opening the vacuum furnace to atmospheric pressure, a pressure difference between the pressure in the recessed space 5 and atmospheric pressure is generated, and the light receiving surface is directly touched. Therefore, the light receiving surface has a desired curved shape, and the solid-state imaging device shown in FIG.

  A second embodiment of the present invention will be described with reference to FIGS. FIG. 2 is a cross-sectional view showing the manufacturing process of the solid-state imaging device. FIG. 4 is a perspective view of a solid-state image sensor bare chip. 4 in FIG. 4 indicates a light receiving element area. 2 in FIG. 2A is a solid-state image sensor bare chip before processing. Reference numeral 7 in FIG. 2B denotes a solid-state image sensor bare chip after processing the opposite surface of the light receiving surface into a concave portion by etching or cutting to a thickness that can form a desired curved shape. However, the thickness of the light-receiving surface is set to a thickness that does not affect imaging even if it is affected by atmospheric pressure of about 1100 hpa to 500 hpa. The size of the concave portion of the solid-state image sensor bare chip 7 after processing shown in FIG. 2 (b) may be larger than that of the light receiving element area 1 in FIG. 2 of FIG.2 (e) is a base which mounts a solid-state image sensor. FIG. 2E shows a completed solid-state imaging device.

  In FIG. 2C, the light receiving surface is pressurized using compressed air 9 from the light receiving surface side of the processed solid-state image sensor bare chip 7 to form a curved shape. Alternatively, pressure is applied with the curved jig 10 shown in FIG. 2D to form a curved shape on the light receiving surface. At this time, pressurization of the compressed air pressure 9 and the curved jig 10 is set to a pressure at which a desired curved shape can be formed after completion. Next, the pedestal 8 is bonded to the opposite surface of the light receiving surface so that the confidentiality of the recessed space 11 in FIG. 2 (e) can be maintained so that a desired curved shape is obtained when the pressure on the light receiving surface is released. . After the base 8 is bonded, the solid-state imaging device shown in FIG.

  A third embodiment of the present invention will be described with reference to FIG. 4 and FIG. FIG. 4 is a perspective view of a solid-state image sensor bare chip. FIG. 3 is a cross-sectional view showing the manufacturing process of the solid-state imaging device. 4 in FIG. 4 indicates a light receiving element area. In FIG. 3A, reference numeral 12 denotes a solid-state image sensor bare chip before processing. Reference numeral 13 in FIG. 3 (b) denotes a solid-state image sensor bare chip that has been processed into a concave portion by etching or cutting the opposite surface of the light receiving surface to a thickness that enables a desired curved shape to be formed after completion. The size of the concave portion of the solid-state image sensor bare chip 13 after processing shown in FIG. 3 (b) may be larger than that of the light receiving element area 1 in FIG. Reference numeral 17 in FIG. 3 (e) denotes an adhesive cured to maintain the curved shape. FIG. 3E shows the completed solid-state imaging device.

  In FIG. 3C, the light receiving surface is pressurized using compressed air 14 from the light receiving surface side of the solid image pickup element bare chip 13 after processing to form a curved shape. Alternatively, pressure is applied with the curved jig 15 shown in FIG. 3D to form a curved shape on the light receiving surface. At this time, pressurization of the compressed air pressure 14 and the curved jig 15 is set to a pressure at which a desired curved shape can be formed after completion. Next, an adhesive 17 is injected into the recessed space 16 on the opposite surface of the light receiving surface, and the adhesive 17 is cured. After the adhesive 17 is cured, the solid-state imaging device shown in FIG. 3E can be obtained that can maintain the curved shape even if there is a large pressure change on the light receiving surface.

  The solid-state imaging device according to the manufacturing method of the present invention can be a characteristic solid-state imaging device. By the way, according to the manufacturing method of claim 1, since it can be manufactured without requiring a large-scale manufacturing apparatus, an inexpensive solid-state imaging device can be obtained. According to the manufacturing method of claim 2, since the light receiving surface is simply pressurized, it can be manufactured in a short time, and an inexpensive solid-state imaging device can be obtained. Further, according to the manufacturing method of the third aspect, since the curved shape is held by the adhesive, a solid-state imaging device with increased mechanical strength can be obtained, and further, since no pedestal is required, the solid-state imaging device can be thinned.

Sectional drawing which shows the manufacturing process of the solid-state image sensor by this invention. (Example 1) Sectional drawing which shows the manufacturing process of the solid-state image sensor by this invention. (Example 2) Sectional drawing which shows the manufacturing process of the solid-state image sensor by this invention. Example 3 The perspective view of a solid-state image sensor bare chip. Sectional drawing which shows schematic structure of the conventional solid-state imaging device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light receiving element area 2 Solid imaging element bare chip before processing 3 Solid imaging element bare chip after processing 4 Base 5 Recessed space 6 Solid imaging element bare chip before processing 7 Solid imaging element bare chip after processing 8 Base 9 Compressed air 10 Curved shape Recessed jig 11 Recessed space 12 Solid imaging device bare chip 13 before processing Solid imaging device bare chip 14 after processing Compressed air 15 Curved jig 16 Recessed space 17 Adhesive 18 Wiring substrate 19 Semiconductor bare chip 20 Curved surface 21 Solid imaging element

Claims (4)

  In the method of manufacturing a solid-state imaging device in which a curvature corresponding to the curvature of field caused by the aberration of the optical system is formed on the light receiving surface, a recess is provided on the opposite surface of the light receiving surface, and a pedestal is adhered to the opposite surface of the light receiving surface in a vacuum A method for manufacturing a solid-state imaging device.   In a method for manufacturing a solid-state imaging device in which a curvature corresponding to the curvature of field caused by the aberration of the optical system is formed on the light receiving surface, a concave portion is provided on the opposite surface of the light receiving surface, and bending is applied by applying mechanical stress or compressed air from the light receiving surface. A method for manufacturing a solid-state imaging device, wherein a pedestal is bonded to the opposite surface of the light-receiving surface after forming the shape.   In a method for manufacturing a solid-state imaging device in which a curvature corresponding to the curvature of field caused by the aberration of the optical system is formed on the light receiving surface, a concave portion is provided on the opposite surface of the light receiving surface, and bending is applied by applying mechanical stress or compressed air from the light receiving surface. A method for manufacturing a solid-state imaging device, characterized in that a shape is formed, an adhesive is put into the space, and the adhesive is cured. A solid-state imaging device manufactured by the manufacturing method according to claim 1, 2 or 3.

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