JPH06334159A - Solid state image sensing device and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide a solid state image sensing apparatus which can surely prevent generation of diffraction image on the display screen and ensures excellent productivity. CONSTITUTION:An optical low-pass filter 2 consisting of a solid state image sensing element 1 and a diffraction grating is closely fixed through a gap regulating body 3. The gap regulating body 3 is composed of a photosensitive resin in the thickness of 30 to 100mum and is provided to regulate a gap between the solid state image sensing element 1 and the optical low-pass filter 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state image pickup device having an optical low pass filter.

[0002]

2. Description of the Related Art In a solid-state image pickup device used in an image pickup device such as a video camera or an electronic still camera, pixels are arranged two-dimensionally and regularly to input an image. Therefore, if the input pixel contains a high frequency component more than necessary, there is a problem that a false signal or a false color signal is generated, and an optical low-pass filter for blocking an unnecessary high frequency component is required. Conventionally, an optical low-pass filter using a quartz plate has been used, but this has been an obstacle to reducing the size and weight of the image pickup device.

On the other hand, in recent years, JP-A-53-11
A technique of an optical low-pass filter using a diffraction grating as disclosed in Japanese Patent No. 9063 is known. In the diffraction grating disclosed in the above-mentioned publication, the pitch of the diffraction grating and the pixel pitch of the solid-state imaging device need to be an integral multiple or an integral multiple. Here, when the focal length of the imaging lens is f, the period of the diffraction grating is d, and the distance between the diffraction grating and the imaging surface is b, the effective period D can be approximately calculated by the following [Equation 1]. it can.

[0004]

[Equation 1] D = f · d / (f−b) Therefore, the effective period D is determined by the focal length f and the distance b between the diffraction grating and the imaging surface. Must be accurately positioned relative to each other.

[0005]

However, as described above, it is not easy at all to accurately position the optical low-pass filter composed of the diffraction grating and the solid-state image pickup device which is the image pickup surface on the order of μm, and therefore the production is difficult. In addition, the property is deteriorated, and the generation of the diffraction grating image cannot be sufficiently prevented.

The present invention is to provide a solid-state image pickup device having an optical low-pass filter composed of a diffraction grating, which can sufficiently prevent a diffraction grating image from being generated on a screen and has high productivity. To aim.

[0007]

According to another aspect of the present invention, there is provided a solid-state image pickup device comprising: a solid-state image pickup device; an optical low-pass filter facing the solid-state image pickup device; and a solid-state image pickup device and an optical low-pass filter. An intervening gap regulator is provided. The method of manufacturing a solid-state imaging device according to claim 2, wherein a step of applying a photosensitive resin on a glass substrate having an optical low-pass filter, and an optical low-pass filter by selectively exposing and developing the photosensitive resin. And a step of fixing the solid-state image sensor to the tip of the gap regulating body.

According to a third aspect of the present invention, there is provided a method of manufacturing a solid-state image pickup device, which comprises a step of applying a photosensitive resin on a silicon wafer having a solid-state image pickup element formed thereon, and a step of selectively exposing and developing the photosensitive resin. It includes a step of forming a gap regulating body on the surface of the element and a step of fixing an optical low-pass filter to the tip of the gap regulating body.

[0009]

According to the solid-state image pickup device of the present invention, since the gap regulator is provided between the optical low-pass filter and the solid-state image pickup device, the optical low-pass filter and the solid-state image pickup device are accurately arranged on the order of μm. It can be positioned and no diffraction grating image is generated on the screen.

Further, according to the method for manufacturing a solid-state image pickup device of the present invention, a photosensitive resin is applied to an optical low-pass filter or a solid-state image pickup element, and this is selectively exposed and developed to form a gap regulator. As a result, it is possible to collectively form a highly accurate gap control body and improve productivity.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a solid-state image pickup device according to an embodiment of the present invention. In the solid-state imaging device of this embodiment, a solid-state imaging device 1 and an optical low-pass filter 2 composed of a diffraction grating are closely attached via a gap regulator 3. The gap regulator 3 is a photosensitive resin having a thickness of 30 to 100 μm, is provided on the peripheral portion of the solid-state image sensor 1, and regulates the gap between the solid-state image sensor 1 and the optical low-pass filter 2. 4 is a package.

FIG. 2 shows a method of manufacturing the solid-state image pickup device of FIG. An optical low-pass filter 2 composed of a diffraction grating is formed on a glass substrate 5 (see FIG. 2 (a)). A photosensitive resin 6 having a thickness of 30 to 100 μm on the glass substrate 5,
For example, it is applied to 55 μm by a spin coating method or the like.
As the photosensitive resin 6, BMRS-1000 (manufactured by Tokyo Ohka Co., Ltd.) or the like is suitable. After applying the photosensitive resin 6, at a temperature of 80 to 150 ° C., for example, 100 ° C., 5
The heat treatment is performed for about a minute to remove the solvent contained in the photosensitive resin 6 ((b) of the same figure).

Next, the reticle 7 is set on the upper surface of the photosensitive resin 6 (FIG. 7C), and i-line 8 of 200 to 400 nm, for example 365 nm is irradiated to develop the photosensitive resin 6. Patterning 6 is performed ((d) of the same figure). As a result, the gap regulating body 3 is formed on the optical low pass filter 2. The gap control body 3 is
The optical low-pass filter 2 is arranged at the peripheral portion, for example, at four corners.

In the embodiment of FIG. 2, the case where the photosensitive resin 6 is applied on the glass substrate 5 to form the gap regulating body 3 for regulating the gap has been described, but the solid-state image pickup device 1 is formed. A photosensitive resin may be applied onto a silicon wafer to form a gap regulator for regulating the gap.

[0015]

According to the solid-state image pickup device of the present invention, since the gap regulator is provided between the optical low-pass filter and the solid-state image pickup device, the optical low-pass filter and the solid-state image pickup device are accurately arranged on the order of μm. It can be positioned and no diffraction grating image is generated on the screen.

Further, according to the method of manufacturing a solid-state image pickup device of the present invention, a photosensitive resin is applied to the optical low-pass filter or the solid-state image pickup element, and the photosensitive resin is selectively exposed and developed to form the gap regulator. Therefore, a highly accurate gap control body can be collectively formed, and productivity is improved.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of a solid-state imaging device of the present invention.

2A to 2D are process diagrams showing a method of manufacturing the solid-state imaging device of FIG.

[Explanation of symbols]

 1 Solid-state image sensor 2 Optical low-pass filter 3 Gap regulator 5 Glass substrate 6 Photosensitive resin 7 Reticle 8 i-line

Claims (3)

[Claims] 1. A solid-state imaging device comprising: a solid-state imaging device; an optical low-pass filter facing the solid-state imaging device; and a gap regulator interposed between the solid-state imaging device and the optical low-pass filter. . 2. A step of applying a photosensitive resin on a glass substrate on which an optical low pass filter is formed, and a gap regulator on the surface of the optical low pass filter by selectively exposing and developing the photosensitive resin. And a step of fixing a solid-state image sensor to the tip of the gap regulator, the method for manufacturing a solid-state image sensor. 3. A step of applying a photosensitive resin on a silicon wafer on which a solid-state image sensor is formed, and a gap regulator is formed on the surface of the solid-state image sensor by selectively exposing and developing the photosensitive resin. And a step of fixing an optical low-pass filter to the tip of the gap regulator, the method for manufacturing a solid-state imaging device.