JP3849248B2 - Imaging device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a light-weight, small, and thin imaging device that can be mounted on a desktop or laptop computer, a mobile phone, and the like, particularly a solid-state imaging device, a drive circuit that drives the solid-state imaging device, and a signal from the solid-state imaging device The present invention relates to an image pickup apparatus integrated with an optical system such as a lens and a diaphragm.
[0002]
[Prior art]
In recent years, imaging devices with built-in solid-state imaging devices, as represented by camera-integrated video, have been widely adopted not only in the consumer field, but also in multimedia fields such as surveillance, broadcasting, medical or videoconferencing, videophones, etc. In addition to the demands for high image quality such as faithful color reproducibility and fine detail expression, there are increasing demands for miniaturization, thickness reduction, weight reduction, etc. that are convenient to carry. In order to meet such a demand, technology development for reducing the size and thickness of an imaging device including a solid-state imaging device and its peripheral circuits has been actively conducted.
[0003]
FIG. 6 shows the structure of a conventional image pickup apparatus. As shown in the figure, a solid-state image pickup device 2 (hereinafter referred to as a CCD chip) and a CCD chip 2 are located in a container 1 made of ceramic or plastic. An insulating substrate 4 on which a peripheral circuit element 3 made of a semiconductor chip such as a vertical transfer unit driving driver (hereinafter referred to as VDr), a CDS, or a DSP is mounted is accommodated.
[0004]
The CCD chip 2 and the peripheral circuit element 3 are both electrically connected to each other by a wire lead 5 such as a gold wire through a wiring formed on the insulating substrate 4, and provided at the peripheral portion of the insulating substrate 4. The electrode pad 6 is bonded to the terminal 8 exposed on the inner surface of the container 1 of the pin lead 7 on the outer periphery of the container 1 by the wire lead 5.
[0005]
The container 1 configured as described above is hermetically sealed with the inside filled with an inert gas by sealing the upper surface of the container 1 with the face plate 9. Reference numeral 10 denotes a translucent glass plate attached to the opening of the face plate 9 located on the upper surface of the CCD chip 2.
[0006]
FIG. 7 shows a configuration of the insulating substrate 4. The die bonding pad 11 for mounting the peripheral circuit element 3 and the signal pad 12 of the peripheral circuit element 3 are bonded to the insulating substrate 4 by the wire leads 5. A connection pad 13 for this purpose, and a conductor wiring group 14 that is a signal line made of aluminum wiring that connects the connection pad 13 and the electrode pad 6 provided on the peripheral edge of the insulating substrate 4 are formed. The peripheral circuit element 3 is mounted on the die bonding pad 11 by die bonding, and the signal pad 12 and the connection pad 13 on the insulating substrate are connected by a wire lead 5 such as a gold wire.
[0007]
[Problems to be solved by the invention]
However, in the configuration of the imaging device described above, interference noise between wirings and noise from outside can easily ride on the power supply line and the signal line, and such noise appears as interference noise in the output image from the imaging device, and the image quality is greatly increased. It will deteriorate. In order to prevent this noise, measures have been taken in the past by increasing the ground layer of the printed circuit board, adding a capacitor to the power supply line, and adding a filter to the signal line, but sufficient noise removal has been achieved. There wasn't.
[0008]
The present invention solves such a problem, and an object thereof is to provide an imaging apparatus capable of effectively reducing noise.
[0009]
[Means for Solving the Problems]
To achieve the above object, the present invention provides a conductive layer formed on a main surface of a circuit board made of an insulating substrate in an imaging device, an insulating layer formed so as to cover the entire surface of the conductive layer, And a conductor wiring group formed so as to cover the entire conductor layer on the upper surface of the insulating layer.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
According to the first aspect of the present invention, there is provided a solid-state imaging device, a driving circuit element for driving the solid-state imaging device, and a video signal processing circuit for processing a video signal output from the solid-state imaging device. An imaging device in which a circuit board on which an element is mounted is placed in a recess of a storage container, the circuit board being an insulating board, a conductor layer formed on the main surface and grounded, and the conductive layer A conductor layer having an insulating layer formed to cover the entire surface of the body layer and a conductor wiring group formed on the upper surface of the insulating layer, and having a large area in which the conductor wiring group is grounded Therefore, noise can be reduced efficiently.
[0011]
According to a second aspect of the present invention, there is provided a solid-state image sensor, a drive circuit element for driving the solid-state image sensor, and a video signal processing circuit for processing a video signal output from the solid-state image sensor. An imaging device having a circuit board on which an element is mounted placed in a recess of a storage container, wherein the circuit board is an insulating substrate, and is formed on a main surface of the first conductor layer and grounded A first insulating layer formed over the entire surface of the first conductor layer , a conductor wiring group formed on the upper surface of the first insulating layer , and a conductor wiring group formed over the conductor wiring group. A second insulating layer; and a second conductor layer formed on the upper surface of the second insulating layer so as to cover the conductor wiring group and grounded. A group is covered from both sides by a first conductor layer and a second conductor layer In order, it is possible to improve the noise reduction effect.
[0012]
According to a third aspect of the present invention, in the imaging device according to the second aspect, the first conductor layer and the second conductor layer are electrically connected at least at one place. Therefore, the reliability of the noise reduction effect can be improved.
[0013]
Next, an embodiment of the present invention will be described with reference to the drawings.
(Embodiment 1)
FIG. 1 shows the structure of the image pickup apparatus according to the first embodiment of the present invention. The basic structure in the cross-sectional view is substantially the same as that of the conventional image pickup apparatus described in FIG. Alternatively, a plastic container, 2 is a CCD chip, 3 is a peripheral circuit element made of a semiconductor chip such as VDr, CDS, or DSP, and 4 is an insulating substrate made of glass or a ceramic substrate.
[0014]
The CCD chip 2 and the peripheral circuit element 3 are both electrically connected to each other by a wire lead 5 such as a gold wire through a wiring (not shown) formed on the insulating substrate 4, and the peripheral edge of the insulating substrate 4. The electrode pad 6 provided in the portion is bonded to the terminal 8 exposed on the inner surface of the container 1 of the pin lead 7 on the outer periphery of the container 1 by the wire lead 5.
[0015]
Further, the upper surface of the container 1 is sealed with a face plate 9 provided with a light-transmitting glass 10, so that the inside thereof is hermetically sealed in a state filled with an inert gas.
[0016]
FIG. 2 is a plan view of the insulating substrate 4 shown in FIG. 1. The peripheral circuit element 3 is die-bonded on a die bonding pad 11 provided on the upper surface of the insulating substrate 4, and its terminal 12 is the insulating substrate 4. Wire bonding is performed to the connection pad 13 of the conductor wiring group 14 made of an aluminum film or the like formed on the upper surface of the metal wire 5 by a gold wire 5 or the like. Reference numeral 15 denotes a conductor layer serving as a ground wiring for noise reduction, which is a feature of the present invention.
[0017]
The characteristics of the present invention in such a wiring structure will be further described with reference to FIG. FIG. 3 is an enlarged cross-sectional view showing a part of the circuit board of the imaging apparatus according to the first embodiment of the present invention shown in FIG. As shown in the figure, a conductor layer 15 such as aluminum is provided on the lower surface of the conductor wiring group 14 shown in the plan view of FIG. 2 on the upper surface of the insulating substrate 4, and an insulating layer 16 made of silicon oxide is provided on the upper surface thereof. Thus, a conductor wiring group 14 made of aluminum or the like is formed. Since the conductor layer 15 has a terminal grounded, and thus the conductor layer 15 is formed on the lower surface of the conductor wiring group 14 serving as a signal line, the conductor wiring group 14 can be protected from external noise. It becomes.
[0018]
(Embodiment 2)
Next, FIG. 4 is an enlarged view of a part of a cross section of a circuit board used in the image pickup apparatus according to the second embodiment of the present invention. This embodiment is the first embodiment. The difference from this structure is that the conductor wiring group 14 is sandwiched between two ground conductors of the first conductor layer 15 and the second conductor layer 25. That is, as shown in the figure, after the second insulating layer 26 made of silicon oxide is provided on the upper surface of the conductor wiring group 14 of the circuit board obtained in the first embodiment, the second insulating layer 26 is provided. A second conductor layer 25 is formed on the upper surface of the conductor layer so as to cover the entire conductor wiring group. Both the first conductor layer 15 and the second conductor layer 25 are ground conductors whose terminals are grounded. Therefore, since the lower surface and the upper surface of the conductor wiring group 14 to be signal lines are completely covered from both surfaces by the first conductor layer 15 and the second conductor layer 25, the conductor wiring group 14 is arranged between the wirings. It is possible to efficiently protect from interference noise and external noise.
[0019]
(Embodiment 3)
Next, FIG. 5 is an enlarged view of a part of a cross section of a circuit board used in an imaging apparatus according to the third embodiment of the present invention. This embodiment is a second embodiment. The difference from this structure is that the first conductor layer 15 and the second conductor layer 25 sandwiching the conductor wiring group 14 are connected by at least one connection hole 31 between the lines of the conductor wiring group 14. is there. That is, as seen in FIG. 5, in the step before the formation of the second conductor layer 25 in the step of the second embodiment, at least one second insulating layer 26 and the first insulating layer 26 between the lines of the conductor wiring group 14 are formed. After forming the connection hole 31 by etching the insulating layer 16, the second conductor layer 25 is formed by vapor deposition or sputtering, and at the same time, the second conductor layer 25 is embedded in the connection hole 31. 1 conductor layer 15. In this way, the lower surface and the upper surface of the conductor wiring group 14 to be signal lines are respectively covered from both surfaces by the first conductor layer 15 and the second conductor layer 25 via the insulating layer, and at least the conductor wiring group 14 Since these ground conductors are connected between one line, the conductor wiring group 13 can be protected from external noise with high reliability.
【The invention's effect】
As is clear from the above embodiments, the present invention provides a conductor layer formed on the main surface of the circuit board, an insulating layer formed over the entire surface of the conductor layer, and an upper surface of the insulating layer. The conductor wiring group is formed, and the signal wiring (conductor wiring group) connected from each semiconductor element to the external circuit is shielded by a ground conductor (conductor layer) having a large electrode area, thereby causing various noises. Accordingly, it has become possible to realize an imaging apparatus having high performance capable of remarkably reducing and thus obtaining a good image output.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an imaging device according to an embodiment of the present invention. FIG. 2 is a plan view of a circuit board of the imaging device according to the first embodiment. FIG. 4 is an enlarged cross-sectional view taken along line AA ′ of the circuit board used in the image pickup apparatus according to the second embodiment of the present invention. FIG. 5 is an image pickup apparatus according to the third embodiment. FIG. 6 is a cross-sectional view of a conventional image pickup apparatus. FIG. 7 is a plan view of a circuit board in the conventional image pickup apparatus.
1 container (storage container)
2 CCD chip (solid-state image sensor)
3 Peripheral circuit elements (drive circuit elements, video processing circuit elements)
4 Insulating substrate (circuit board)
14 Conductor group 15 Conductor layer 16 Insulating layer

Claims (3)

  A circuit board including a solid-state image sensor, a drive circuit element for driving the solid-state image sensor, and a video signal processing circuit element for processing a video signal output from the solid-state image sensor The circuit board is an insulating substrate, the conductor layer is formed on the main surface and grounded, and the insulating layer is formed so as to cover the entire surface of the conductor layer. An imaging device having a layer and a conductor wiring group formed on the upper surface of the insulating layer. A circuit board including a solid-state image sensor, a drive circuit element for driving the solid-state image sensor, and a video signal processing circuit element for processing a video signal output from the solid-state image sensor An imaging device mounted on a concave portion of the first conductive layer, wherein the circuit board is an insulating substrate, the first conductive layer formed on the main surface and grounded, and the entire surface of the first conductive layer A first insulating layer formed so as to cover; a conductor wiring group formed on an upper surface of the first insulating layer ; a second insulating layer formed covering the conductor wiring group; and a second An imaging device comprising: a second conductor layer formed on an upper surface of an insulating layer so as to cover the conductor wiring group and grounded.   The imaging device according to claim 2, wherein the first conductor layer and the second conductor layer are electrically connected at least at one place.

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