Patent Description:
In general structure of known image sensors used in digital cameras, a sensor chip comprising a silicon substrate and others is mounted within a package formed of ceramic or plastic with a recessed cavity. However, as packages have decreased in weight and size, a so-called packageless structure as disclosed in PTL <NUM> is proposed in which a sensor chip is mounted directly on a printed circuit board made of glass epoxy or the like. The document <CIT> is a relevant prior art.

However, as disclosed in PTL <NUM>, the packageless structure needs to heat the printed circuit board in connecting the sensor chip and the printed circuit board with wire bonding. This has a problem in that an area of the printed circuit board in which components can be disposed is decreased.

Furthermore, an electrical inspection is needed after the sensor chip is mounted. This requires an additional terminal for inspection on the printed circuit board, causing the problem of increasing the board size. Furthermore, providing the terminal for inspection to output lines operating at high-speed clock will add a stub to the output line, and thus may degrade the quality of the output signal.

An object of the present invention is to provide an image capturing unit with a packageless structure that allows an optimum inspection of the sensor chip in a manufacturing process and an inspection process without decreasing the signal quality.

To achieve the above object, an image capturing unit according to the present invention is an image capturing unit as recited in claim <NUM> including a semiconductor chip constituting an image sensor and a substrate on which the semiconductor chip is mounted. The image capturing unit is characterized by including a plurality of input wiring lines for controlling the semiconductor chip, a plurality of first electrodes connecting to the input wiring lines, and an input connector connecting to the input wiring lines. The substrate includes, in an opposite surface from a surface on which the semiconductor chip is mounted, a first area for mounting an electronic component and a second area for use in mounting the semiconductor chip. The connector is disposed in the first area. At least one or more of the first electrodes are disposed in the second area.

The present invention provides an image capturing unit with a packageless structure that allows an optimum inspection of a sensor chip in a manufacturing process and an inspection process without decreasing the signal quality.

Embodiments of the present invention will be described hereinbelow with reference to the drawings. In all of the drawings, components having the same function are denoted by the same reference sign, and a repeated description thereof will be omitted. The components are not limited to the details of the embodiments and can be corrected as appropriate.

<FIG> is a diagram illustrating, in outline, the configuration of an image capturing unit of an embodiment of the present invention.

Reference sign <NUM> denotes a sensor chip that outputs an image signal according to incident light. In the present embodiment, the sensor chip <NUM> is a semiconductor chip, such as a complementary metal-oxide semiconductor (CMOS) image sensor, formed on a silicon substrate. Alternatively, the sensor chip <NUM> may be a charge-coupled device (CCD) sensor or an image sensor made of a semiconductor other than silicon. The present invention is suitable for the configuration of the sensor chip <NUM> including multiple input and output signal lines and is more suitable for laminated image sensors in which a signal processing chip for signal processing is laminated on an imaging chip including a photoelectric conversion unit that converts light to electricity.

Reference sign <NUM> denotes an imaging substrate. In the present embodiment, the imaging substrate <NUM> is a printed circuit board, on which components <NUM> (described later) are disposed. The individual patterns on the imaging substrate <NUM> are made of metal with low electric resistance, such as gold and copper, and are electrically connected to the sensor chip <NUM> using wire bonding wiring or the like using gold wires or the like. The imaging substrate <NUM> is preferably a rigid substrate and is made of glass epoxy or the like in consideration of stability for mounting the sensor chip <NUM>. However, this is not intended to limit the present invention. The imaging substrate <NUM> may be a flexible substrate made of a plastic material or a low-temperature co-fired ceramic (LTCC) substrate made of ceramic and copper wires. In other words, the imaging substrate <NUM> may be any substrate in which patterns made of a metal wire, such as a copper wire, is formed on a specific material and on which the components can be mounted. The printed circuit board may be a substrate including a plurality of layers composed of different materials that are made conducting through vias or the like.

Reference sign <NUM> denotes an electronic component. The electronic components <NUM> include discrete components, such as capacitors, resistors, and coils, necessary for operating the sensor chip <NUM>. The electronic components <NUM> further include IC chips, such as regulators for supplying power for operating the sensor chip <NUM> and an oscillator that supplies a clock signal. The electronic components <NUM> may include other components not for use in operating the sensor chip <NUM>, such as a thermometer that monitors the state of the sensor chip <NUM> and a memory that stores the individual information on the sensor chip <NUM>. The electronic components <NUM> are generally mounted on the opposite surface of the imaging substrate <NUM> from the sensor chip <NUM>. Alternatively, a capacitor for removing noise, and so on may be mounted on the same surface such as that of the sensor chip <NUM> because they are preferably close to connection terminals.

Reference sign <NUM> denotes a connector including a plurality of electrical contacts. An example is a board-to-board (B-to-B) connector, which is a component for transferring power and signals between the imaging substrate <NUM> and an external substrate including a signal processing chip for processing captured signals obtained from the sensor chip <NUM>, to which various signals are connected in a lump. The connector may be a connector for connecting a flexible substrate. The connector <NUM> is mounted on the opposite surface of the imaging substrate <NUM> from the sensor chip <NUM>. If the number of terminals that need to be connected to the external substrate increases with an increase in the function of the sensor chip <NUM>, the size of the connector <NUM> will also increase. In this case, a plurality of connectors <NUM> are preferably used to connect to the external substrate.

Referring to <FIG>, the range on the imaging substrate <NUM> indicated by arrow <NUM> is an area that substantially coincides with the back of the sensor chip <NUM>, indicating a component area in which the components <NUM> and the connector <NUM> are disposed. The range indicated by arrow <NUM> is an area around the component area <NUM>, indicating a forbidden area in which the electronic components <NUM> and the connector <NUM> are not disposed. To drive the sensor chip <NUM>, multiple components are necessary and need to be densely packed close in a narrow range. However, the imaging substrate <NUM> can be deformed due to heat or the like, and the electronic components <NUM> are preferably mounted not in the peripheral portion, which is significantly affected by the deformation, but in the vicinity of the back of the sensor chip <NUM>. In the present embodiment, the component area <NUM> corresponds to the first area, and the forbidden area <NUM> corresponds to the second area. It is preferable to provide wire bonding pads <NUM> (described later) on the opposite surface from the area corresponding to the forbidden area <NUM>.

Referring to <FIG>, the configuration of an image capturing unit according to an embodiment of the present invention, different from the configuration in <FIG>, will be described. In <FIG>, the component area <NUM> is larger than the back of the sensor chip <NUM>. This is a configuration in the case where the components <NUM> for driving the sensor chip <NUM> are large in number or size. In <FIG>, the component area <NUM> increases in size and is larger than the area in which the wire bonding pad <NUM> is disposed. In the present invention, the size of the component area <NUM> is not limited as long as the imaging substrate <NUM> can be hold in heating or manufacturing the wire bonding pad <NUM>. The component area <NUM> and the forbidden area <NUM> are determined depending on the size of the sensor chip <NUM>, the number of components <NUM>, and so on.

Referring back to <FIG>, reference sign <NUM> denotes a wire bonding pad for connecting the sensor chip <NUM> and the imaging substrate <NUM> together by wire bonding with gold wires or the like. Specifically, the wire bonding pad <NUM> is an electrode formed on the surface of the imaging substrate <NUM> by surface treatment, such as gold plating. The wire bonding pad <NUM> is disposed on the same surface of the imaging substrate <NUM> such as that of the sensor chip <NUM>.

Reference sign <NUM> denotes a check pad (hereinafter sometimes referred to as CP), which is an electrode formed on the surface layer of the imaging substrate <NUM>, like the wire bonding pad <NUM>, by, for example, gold, copper, aluminum, or solder plating. The CPs <NUM> are disposed on the same surface of the imaging substrate <NUM> such as that of the connector <NUM>.

The area on the imaging substrate <NUM> indicated by arrow <NUM> is a heating area to which a heater or the like is to be brought into contact to heat the wire bonding pads <NUM> in wire bonding. The area <NUM> is also used to fix and position the imaging substrate <NUM> in manufacturing the image capturing unit, in addition to heating the wire bonding pads <NUM>. In other words, the forbidden area <NUM> needs only have an area necessary for a fixing holder or the like to come into contact. The outer shape of the imaging substrate <NUM> increases or the component area <NUM> for the components decreases as the area of the forbidden area <NUM> increases. For that reason, more specifically, the forbidden area <NUM> is preferably inside the outer periphery of the imaging substrate <NUM> by about <NUM> to <NUM>. The component area <NUM> is preferably the same area as the outer periphery of the sensor chip <NUM> or the outer periphery of the substrate inside the sensor chip <NUM> by about <NUM> to <NUM>. Although the forbidden area <NUM> is preferably disposed along the four sides of along the outer periphery of the imaging substrate <NUM>, this is not essential. For example, the forbidden area <NUM> may be disposed on one side or two sides along the outer periphery of the imaging substrate <NUM>, and each areas can be of different sizes and/or shapes as long as the fixing holder can be brought into contact.

Reference sign <NUM> denotes a cover glass for sealing the sensor chip <NUM>. The cover glass <NUM> has an antireflection coat and an infrared cut coat. The cover glass <NUM> may have the effect of an optical low-pass filter. Reference sign <NUM> denotes a frame, which is formed around the outer periphery of the wire bonding pads <NUM>. The frame <NUM> is bonded to the imaging substrate <NUM> and the cover glass <NUM> to seal the sensor chip <NUM>. The sides of the frame <NUM> do not need to be perpendicular to the imaging substrate <NUM> and have a predetermined inclination to suppress the reflection of the sides. The frame <NUM> is formed of resin or the like but may be formed of a ceramic material, a metallic material, or combination thereof. The frame <NUM> may include a fixing unit made of metal or the like for fixing to the main body of the image capturing apparatus, described later.

Next, the procedure of manufacture (assembly) of the image capturing unit will be described. <FIG> is a diagram illustrating, in outline, the manufacturing procedure of an image capturing unit of an embodiment of the present invention. <FIG> illustrates a state of only the imaging substrate <NUM>, in which the components <NUM> and so on are not mounted. The assembly is performed, with the imaging substrate <NUM>, which is a combination of a plurality of substrates, fixed to a predetermined jig, such as a tray (omitted in <FIG>). The wire bonding pads <NUM> and the CPs <NUM> are formed on the imaging substrate <NUM>, as described above. Patterns for mounting the components <NUM> and wires connecting the components are also formed (not illustrated).

<FIG> illustrates a state in which the components <NUM> and the connector <NUM> are mounted on the imaging substrate <NUM>. The components are mounted on the imaging substrate <NUM> by reflow soldering or the like in which it is coated with cream solder or the like using a predetermined mask. The wire bonding pads <NUM> may be surface-treated using a sputtering technique.

<FIG> illustrates a state in which the frame <NUM> is bonded to the imaging substrate <NUM>. The bonding is performed using a photo-curable resin or the like, but any other method can be used in the present invention. <FIG> illustrates a state in which the sensor chip <NUM> is mounted on the imaging substrate <NUM>. The sensor chip <NUM> is fixed to the imaging substrate <NUM> with an adhesive (not illustrated). <FIG> illustrates a state in which the sensor chip <NUM> and the wire bonding pads <NUM> are bonded by wire bonding. In the wire bonding operation for connecting the sensor chip <NUM> and the imaging substrate <NUM>, the sensor chip <NUM> and the imaging substrate <NUM> are heated on a heat stage to melt metal for use in wire bonding. Lastly, in <FIG>, the sensor chip <NUM> is sealed with the cover glass <NUM>, so that the image capturing unit is assembled.

The image capturing unit in the present embodiment checks whether the image capturing unit manufactured in the manufacturing procedure illustrated in <FIG> can normally operate (generate electrically normal signals). The image capturing unit supplies power and clock to the sensor chip <NUM> and determines whether a predetermined signal is output (specifically described later). If an expected signal is output, the image capturing unit is determined to be a nondefective item, and if not, the image capturing unit is determined to be a defective item. The sensor chip <NUM> mounted in the image capturing unit of the present embodiment is inspected for operation also in a wafer state before assembling. The details of inspection in the wafer state is the same as the inspection of the image capturing unit, described later. In other words, the sensor chip <NUM> is inspected twice. This is because the sensor chip <NUM> is heated during wire bonding and is brought into contact with various components during the assembly process, as described with reference to <FIG>, and in the sequence of operations, the sensor chip <NUM> can fail especially before being sealed with the cover glass <NUM>. For this reason, it is necessary to check whether the image capturing unit normally operates after being assembled. An image capturing unit with a cavity structure is sealed with the cover glass <NUM> before being mounted on a printed circuit board to which multiple electronic components are mounted. This allows for pre-mounting inspection at the stage of a small package. However, when image capturing units with a packageless structure are inspected after being sealed with the cover glass <NUM>, the inspection is performed with the inclusion of the printed circuit board. In this case, not only the sensor chip <NUM> but also the imaging substrate <NUM> and the other electronic components are inspected. In some cases, the size of the image capturing unit is relatively large, which requires a simple configuration for inspection.

Referring next to <FIG>, a circuit block diagram for the CPs <NUM> for use in inspection and connection of the components will be described.

<FIG> illustrates, in outline, the signal relationship of an image capturing unit according to an embodiment of the present invention. Reference sign <NUM> denotes an input connector of the connector <NUM>. The input connector <NUM> is a connector for connecting to an external substrate including a control unit that controls the sensor chip <NUM> so that it captures images, to which signals for driving the sensor chip <NUM> are connected. The signals for driving the sensor chip <NUM> in the present embodiment include a clock signal, a synchronization signal, a serial communication signal, and a power source. The signals input from input connector <NUM> are input to the sensor chip <NUM> through input wiring lines <NUM> wired on the imaging substrate <NUM>. Part of the power supply circuit for driving the sensor chip <NUM> can supply stable power to the sensor chip <NUM> using linear regulators <NUM> disposed in intermediate points of the wires <NUM>. The linear regulators <NUM> are not absolutely necessary. Power may be directly supplied via the input connector <NUM>. The number of signals connected to the input connector <NUM> is about ten.

Reference sign <NUM> denotes an output connector of the connector <NUM>. The output connector <NUM> is a connector for connecting to an external substrate including a signal processing unit for generating image data from an output signal from the sensor chip <NUM>, to which serial signal lines and so on for outputting signals are connected. The output signals from the sensor chip <NUM> in the present embodiment include not only pixel signals from the pixels but also information on the output pixel signals (addresses, attributes, and so on of the pixels), a header or footer, synchronous code, and a clock signal for receiving image signals. Furthermore, if the sensor chip <NUM> includes a process circuit for correcting or calculating the obtained image signals, the processing result may be output as output signals. The signals output to the output connector <NUM> are output from the sensor chip <NUM> through the output wiring lines <NUM> wired on the imaging substrate <NUM>. Since the signals from the sensor chip <NUM> require high-speed transmission, the output wiring lines <NUM> are differential serial signal lines conforming to the low-voltage differential signaling (LVDS) standard or the scalable low-voltage signaling (SLVS) standard. The number of output channels from the sensor chip <NUM> is <NUM>, and <NUM> signal lines are wired at equal length on the imaging substrate <NUM>.

The CPs <NUM> are connected to the corresponding input wiring lines <NUM> between the input connector <NUM> and the sensor chip <NUM> via predetermined wires. In other words, the sensor chip <NUM> can be driven via the CPs <NUM> without connecting the input connector to an external substrate including a control unit. While the details of control of the sensor chip <NUM> using the CPs <NUM> will be described later, the CPs <NUM> are mainly used to execute electrical inspection of the sensor chip <NUM> without using the input connector <NUM> in inspecting the image capturing unit. In contrast, it is preferable not to connect the CPs <NUM> to the differential pair wiring lines of the output wiring lines <NUM>. This is for the purpose of preventing the signal quality of the output signals from the sensor chip <NUM> from decreasing because the output signals from the sensor chip <NUM> are higher than the input signals, and connecting the CPs <NUM> to the output wiring lines <NUM> forms stub wiring.

Referring to <FIG>, the signal relationship of an image capturing unit according to ab embodiment of the present invention, different from that of <FIG>, will be described. In <FIG>, the CPs <NUM> are connected also in the wiring lines between the linear regulators <NUM> and the sensor chip <NUM>. This configuration allows for inputting inspection voltages other than the voltages generated by the linear regulators <NUM> to the sensor chip <NUM>. Since the linear regulators <NUM> are components for supplying voltages for the normal operation of the sensor chip <NUM>, this configuration is needed for inspection using another voltage. For example, by applying a high voltage or a low voltage, the sensor chip <NUM> can be operated in an inspection drive mode, or by applying a reverse bias, inspection in an abnormal state can be performed. However, if the voltages input to the sensor chip <NUM> via the CPs <NUM> exceed the rated voltages of the linear regulators <NUM>, the linear regulators <NUM> are damaged. For this reason, the voltage range is limited, and this configuration is advantageous for inspection in which the voltage range is not significantly changed.

Referring next to <FIG>, the signal relationship of an image capturing unit according to an embodiment of the present invention, different from those of <FIG> and <FIG>, will be described. In <FIG>, switches <NUM>, which are switch circuits, are disposed between the linear regulators <NUM> and the sensor chip <NUM>. This configuration allows for applying various voltages from the outside via the CPs <NUM> between the sensor chip <NUM> and the switches <NUM>. In the case of <FIG>, the power applied from the outside to the linear regulators <NUM> via the switches <NUM> can be separated. This allows the voltage to be applied to the sensor chip <NUM> via the CPs <NUM> to be set in a wide range without being limited by the power-supply voltages of the linear regulators <NUM> or the like. Signals and power for controlling the switches <NUM> can be provided by being input via the CPs <NUM> likewise.

By connecting the CPs <NUM> to the input signals of the sensor chip <NUM>, and not connecting the CPs <NUM> to the output signals, as has been described with reference to <FIG>, signals necessary for inspection can be input to the sensor chip <NUM>, with the signal quality of the output signals kept. This also allows power necessary for the inspection of the sensor chi <NUM> to be easily applied from the outside.

Referring next to <FIG>, the connection relationship among the contacts in inspection and in normal usage will be described. <FIG> illustrates, in outline, the connection relationship in the inspection and the usage of an image capturing unit of an embodiment of the present invention.

<FIG> is a diagram illustrating the connection relationship in the inspection of the image capturing unit. Reference sign <NUM> denotes an interface substrate of an inspection apparatus. The image capturing unit is attached to the substrate for inspection. The interface substrate <NUM> supplies signals for driving the sensor chip <NUM> via the CPs <NUM> and receives output signals via the output connector <NUM>. Reference sign <NUM> denotes an inspection connector, which is connected to the output connector <NUM>. General B-to-B connectors perform holding to prevent dropping after being combined. In contrast, the interface substrate <NUM> includes dedicated non-holding components to repeatedly attach and detach a plurality of image capturing units. Reference sign <NUM> denotes an inspection pin, which is connected to the CP <NUM> when the image capturing unit is attached to the interface substrate <NUM>. The inspection pin <NUM> is an extendable contact, which can establish electrical conduction by being pushed against the CP <NUM>. The inspection pin <NUM> is used to supply a signal and power for driving the sensor chip <NUM>.

<FIG> is a diagram illustrating the connection relationship of the image capturing unit in normal use. "In normal use" indicates a case in which the image capturing unit is installed in an image capturing apparatus (described later) and is used in an operation for capturing a subject image through a lens. Reference sign <NUM> denotes a first connector to be connected to the output connector <NUM>, and reference sign <NUM> denotes a second connector to be connected to the input connector. When the image capturing unit is installed in an image capturing apparatus or the like, the image capturing unit is connected to another substrate via the first connector <NUM> and the second connector <NUM>. The first connector <NUM> and the second connector <NUM> are mounted on different substrates (not illustrated). The input connector <NUM> and the output connector <NUM> are precise electronic components but certainly have dimensional errors in mass production. Furthermore, adding the accuracy of mounting to the imaging substrate <NUM>, the accuracy of the flatness of the imaging substrate <NUM> itself, and so on may cause the dimensions to deviate from a dimensional range for normal engagement. For these reasons, mounting the first connector <NUM> and the second connector <NUM> on the same substrate would not ensure normal engagement because of their tolerances. To prevent it, the first connector <NUM> and the second connector <NUM> are preferably disposed on different substrates and are individually connected. Alternatively, the same substrate may be used, as long as it is a flexible substrate that can accommodate the tolerances.

For inspection, the image capturing unit is attached to the inspection apparatus using an automatic transfer machine or the like in consideration of adhesion of dust and an electrostatic discharge failure. In this case, in order to automatically connect the first connector <NUM> and the second connector <NUM>, the connectors are preferably disposed on a single substrate. However, this may not ensure the engagement of the connectors, as described above. Disposing the connectors on different substrates or a flexible substrate will require a mounting transfer machine with a complicated structure and increase the inspection time. In other words, when a plurality of image capturing units are to be inspected using one inspection apparatus, two connectors cannot be used, decreasing the productivity.

Accordingly, even in the configuration including two or more connectors, using only the output connector <NUM> at the time of inspection, and using the CPs <NUM> in inputting to the sensor chip <NUM>, as described above, ensures connection using a very simple transfer machine. This has the advantageous effect of enabling stable inspection in a short tact time.

Referring next to <FIG>, the two-dimensional positional relationship among the component area <NUM> and the area <NUM> of the imaging substrate <NUM> and the CPs <NUM> will be described. <FIG> are diagrams illustrating, in outline, the layout of an imaging substrate of an embodiment of the present invention.

<FIG> illustrates the layout of the surface (front) of the imaging substrate <NUM> on which the sensor chip <NUM> is mounted. <FIG> illustrates the layout of the surface (back) of the imaging substrate <NUM> on which the components <NUM> are disposed. Reference sign <NUM> denotes an area in which the sensor chip <NUM> is disposed. The wire bonding pads <NUM> are disposed around the sensor chip <NUM>.

On the back of the imaging substrate <NUM> on which the components are disposed, the input connector <NUM>, the output connector <NUM>, the components <NUM>, and so on are disposed in the component area <NUM>. The area <NUM> is outside the component area <NUM> and extends to the end of the imaging substrate <NUM>. Here, the image-sensor area <NUM> is illustrated also in the layout of the back of the substrate on which the components <NUM> are disposed for simplicity sake. However, the sensor chip area <NUM> is not actually present on the front of the substrate on which the components are disposed. Although the component area <NUM> is described as an area smaller than the sensor chip <NUM>, as illustrated in <FIG>, the present invention is not limited to this configuration.

The CPs <NUM> are disposed in the area <NUM>, as described above. The CPs <NUM> are most preferably disposed on one or more sides depending on the number of CPs <NUM>. Disposing the CPs <NUM> on the long side of the image sensor rather than the short side can increase the area for the CPs <NUM>.

<FIG> illustrates another example of the arrangement of the CPs <NUM>, in which the CPs <NUM> are disposed on the side symmetric about the direction in which the output connector <NUM> is disposed. The arrangement illustrated in <FIG> allows the pressure applied to the imaging substrate <NUM> when the inspection connector <NUM> and the inspection pins <NUM> are pushed against the image capturing unit at the inspection described above to be made uniform. The uniform pressure prevents the components from being damaged and increases the stability to conduction of the contacts.

<FIG> illustrates another example of the arrangement of the CPs <NUM>, some of which are disposed also in the component area <NUM>. For example, in the case of the wiring in <FIG> or <FIG>, it may be preferable to dispose the CPs <NUM> near the output of the linear regulators in terms of performance. In such a case, the CPs <NUM> is preferably disposed in the component area <NUM>. However, disposing the CPs <NUM> in the component area will decrease the area of the component area <NUM> for the components <NUM>. For this reason, also even in the case where the CPs <NUM> are disposed in the component area, the number of CPs <NUM> in the area <NUM> is preferably larger than the number of CPs in the area <NUM>.

<FIG> illustrates another example of the arrangement of the CPs <NUM>, illustrating a case in which the CPs <NUM> are arranged in multiple rows and a case in which they are arranged in a staggered pattern. However, disposing multiple rows of CPs <NUM> are arranged, as in the drawing, can increase the area of the area <NUM> and decrease the area of the component area <NUM>, which is advantageous when the area <NUM> is sufficiently large.

Disposing many of the CPs <NUM> in the area <NUM> allows for not only suitably disposing the component area <NUM> but also providing the area <NUM> on the periphery of the substrate. This also contributes to the stability to conduction during inspection. This also allows for suitably supporting the substrate in heating during wire bonding and manufacturing.

Disposing the CPs <NUM> not for the output connector <NUM> through which high-speed signal lines pass but only for input signals allows for inspection in the case of two connectors and allows inspection without decreasing the output signal quality. This also allows for supplying a voltage necessary for inspection to the sensor chip <NUM> without being influenced by the voltages of the linear regulators.

Referring next to <FIG>, an embodiment in which the image sensor described in the above embodiments is applied to a digital camera, which is an image capturing apparatus, will be described in detail.

In <FIG>, reference sign <NUM> denotes a lens unit that forms an optical image of the subject on an image sensor <NUM> including the sensor chip <NUM>, of which zoom control, focus control, aperture control and so on are performed by a lens driving unit <NUM>. Reference sign <NUM> denotes a mechanical shutter, which is controlled by a shutter control unit <NUM>. Reference sign <NUM> denotes an image sensor for receiving an image of the subject formed by the lens unit <NUM> as an image signal. Reference sign <NUM> denotes a captured-signal processing circuit that performs various corrections on the image signal output from the image sensor <NUM> or compresses data.

Reference sign <NUM> denotes a timing generation circuit which is a driving unit that outputs various timing signals to the image sensor <NUM> and the captured-signal processing circuit <NUM>, reference sign <NUM> denotes a control circuit that performs various kinds of calculation and controls the entire image capturing apparatus, and reference sign <NUM> denotes a memory for temporarily storing image data. Reference sign <NUM> denotes an interface for recording or reading to or from a recording medium, <NUM> denotes a detachable recording medium, such as a semiconductor memory, for recording or reading image data, and <NUM> denotes a display that displays various pieces of information and captured images. Reference sign <NUM> denotes a metering unit that detects the luminance of the subject. Reference sign <NUM> denotes a distance measuring unit that detects a focus.

As has been described above, the sensor chip <NUM> is mounted on the imaging substrate <NUM>, and the imaging substrate <NUM> is connected to a substrate on which the captured-signal processing circuit <NUM> and the timing generation unit <NUM> are mounted via the connector.

Next, the operation of the digital camera with the above configuration during shooting will be described.

When the main power source is turned on, the power source of the control system is turned on, and the power source of the image capturing circuit, such as the captured-signal processing circuit <NUM>, is turned on.

Then, when a release button (not illustrate) is pressed, a high-frequency component is taken out on the basis of a signal output from the distance measuring unit <NUM> to calculate the distance to the subject with the control circuit <NUM>. Thereafter, the lens unit is driven by the lens driving unit <NUM>, and it is determined whether the subject is in focus. If it is determined that the subject is not in focus, the lens unit is driven again, and distance measurement is performed.

After focusing is confirmed, an image capturing operation is started.

After completion of the image capturing operation, an image signal output from the sensor chip <NUM> is processed by the captured-signal processing circuit <NUM>, and the signal is written to the memory <NUM> by the control circuit <NUM>. The data accumulated in the memory <NUM> is recorded in the detachable recording medium <NUM>, such as a semiconductor memory, via the recording-medium control I/F <NUM> under the control of the control circuit <NUM>.

The image may be directly input to a computer or the like via an external I/F for processing.

The image capturing units and image capturing apparatuses described in the embodiments are applicable to various applications. For example, the image capturing units can be used in sensing not only visible light but also infrared light, ultraviolet light, X-rays, and other light. The image capturing apparatuses are typified by digital camera but may be used for mobile phones with a camera, such as smartphones, monitoring cameras, and game machines. The image capturing apparatuses can also be used for endoscopes, angiographic medical devices, cosmetic devices for observing skin or scalps, and video cameras for capturing sports and action moving images. The image capturing apparatuses can also be used for traffic cameras for traffic or vessel monitoring, such as drive recorders, academic-application cameras for astronomical observation or analyte observation, home electric appliances with camera, machine vision, and so on. In particular, the machine vision is applicable not only in robots in factories or the like but also in agriculture and fishery.

The configurations of the image capturing apparatuses in the above embodiments are mere examples, and the configurations of the image capturing apparatuses to which the present invention can be applied are not limited to the configuration illustrated in <FIG>. The circuit configurations of the components of the image capturing apparatuses are not limited to the configurations illustrated in the drawings.

The present invention can be implemented by processing of supplying a program for implementing one or more functions of the above-described embodiments to a system or apparatus via a network or storage medium, and causing one or more processors in the computer of the system or apparatus to read out and execute the program. The present invention can also be implemented by a circuit (for example, an ASIC) for implementing one or more functions.

The above-described embodiments merely illustrate examples of embodiment in implementing the present invention. Accordingly, the technical scope of the present invention should not be limitedly interpreted based on the embodiments. That is, the present invention can be implemented in variety forms within the technical idea and primary features of the present invention.

Claim 1:
An image capturing unit comprising a semiconductor chip (<NUM>) constituting an image sensor and a substrate (<NUM>) on which the semiconductor chip (<NUM>) is mounted, the image capturing unit comprising:
a plurality of input wiring lines (<NUM>) for controlling the semiconductor chip (<NUM>);
a plurality of first electrodes (<NUM>) connecting to the input wiring lines (<NUM>); and
an input connector (<NUM>, <NUM>) connecting to the input wiring lines (<NUM>),
wherein the substrate (<NUM>) includes a first area (<NUM>) and a second area (<NUM>) on an opposite surface to a surface on which the semiconductor chip (<NUM>) is mounted,
wherein the connector (<NUM>, <NUM>) is disposed in the first area (<NUM>), and at least one or more of the first electrodes (<NUM>) are disposed in the second area (<NUM>), and
wherein the semiconductor chip (<NUM>) can be driven via the plurality of first electrodes (<NUM>).