JPH11111913A - Function variable semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable change or addition of a function in a device capable of high integration such as an ASIC, without the use of a programmable device such as a PLD, PGA, or the like. SOLUTION: This semiconductor device is equipped beforehand with a function varying means before and behind the functional block (at the interface part with the chip of other functional block), where there is a possibility of functional changes (addition) from among a plurality of functional blocks (units of functions) made in a substrate 1. The function changing means comprises a connection means 5, which connects the chip of the functional block having a function after change at the time of change of the function and validates the function, and a separation means 4 which invalidates the function by cutting off the functional block prior to the change from the circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device capable of partially changing or adding a function of a circuit built in a semiconductor chip or a printed circuit board.

[0002]

2. Description of the Related Art Conventionally, a PLD (Programmable Logic) has been used as a device whose circuit contents can be changed.
Device, programmable logic device) or F
PGA (Field Programmable Ga)
te Array, a field-programmable gate array) and the like. These devices have problems such as-low integration,-slow speed,-inability to incorporate a large-scale memory,-high cost. These are due to the built-in rewritable mechanism inside the device. On the other hand, ASIC (Applicat
Many custom devices such as ion specific ICs (application-specific ICs) have a large-scale memory built-in due to miniaturization of processes. In addition, miniaturization of the process has pushed the degree of integration so far that only a few devices that required a large number of devices in order to realize one function have been required. This has clarified the concept of chipset, and in recent years these chipsets have been sealed in the same package to reduce the size of the system.
Multi-chip module MCM (Mu
lti Chip Module) has received much attention.

In an MCM using such a large-scale device with a high degree of integration as a chip constituting a functional block, it is desired to be able to modify an existing functional block or add a new functional block. . For example, taking an MCM for color conversion as an example, in recent years, RGB has been changed from YMC to YMC.
When color conversion (correction) is performed, linear interpolation, in which the count is uniquely determined, has been changed to non-linear interpolation, a direct lookup method, in order to improve image quality. The direct lookup method is a method of directly determining a converted YMC value from an input RGB value regardless of a coefficient.
Although nonlinear interpolation is possible, there is a disadvantage that a large-scale memory space is required. Therefore, various devices for reducing the memory space have been considered, but the image quality is inevitably reduced due to interpolation. However, with the progress of semiconductor device manufacturing, the miniaturization of the process has progressed. For example, when the size is reduced from 0.8 μm to 0.35 μm, a memory having the same area as a conventional memory and a little more than five times the capacity has become possible. Can be used in place of the existing memory, the image quality can be improved. Therefore, a means for changing an existing memory chip to a new memory chip having an increased capacity in the MCM is desired. Generally, means for changing an existing functional block in the MCM to a new functional block is desired.

[0004] Also, RGB in color copiers
Take the example of MCM which performs color conversion (correction) from to YMC.
As shown in FIG. 14 (a), K,
In the case where each color of Y, C, and M is configured to perform color conversion processing in series in time, there is a case where K, Y, and
In some cases, high-speed processing is performed by allocating one chip to each of the colors C and M and performing parallel processing.
In FIG. 14A, a page memory 1411 is a memory for holding the same input data until the last conversion in order to use the same input data in each color conversion performed sequentially. Color converter 1
412 has a color conversion function corresponding to the number of copy modes,
A multiplexer (MUX) 1413 is a color conversion unit 1412
Is used to select an output corresponding to the designated copy mode from among the outputs of. FIG. 14B does not require a page memory because the conversion of each color is performed in parallel.
Each of the color conversion units 1421 to 1451 and the multiplexer 1422 in FIG.
The same configuration as described above can be used. However, since there is a difference in the presence or absence of a page memory, it is not possible to share the two MCMs for the serial processing in FIG. In order to increase the reliability and simplify the manufacturing process of a large-scale device with a high degree of integration, it is preferable to use a circuit configuration that can be commonly used for various applications. In the case of FIG. 14, since each chip has the same color conversion unit and multiplexer and only a different page memory, a common portion is fixedly provided, and if an MCM capable of adding a different portion is created, the commonalization is achieved. MCM can be realized. However, this was not possible with the prior art. For example, a margin 1 to which a page memory can be added as shown in FIG.
An MCM 146 provided with a color conversion unit 1462 and a multiplexer 1463 is conceivable. Thus, by additionally connecting the page memory to the margin 1461, the configuration shown in FIG. However, in this case, since there is no connection means between the input terminal and the color conversion unit 1462, it cannot be used in FIG. Conversely, the input section of the color conversion section 1462 is connected from the beginning to the input terminal 1464 of the chip.
If the chip is connected to the, the page memory cannot be added.

[0005] As a semiconductor device whose function can be changed, for example, there is one described in Japanese Patent Application Laid-Open No. 7-212868.
In this configuration, a first function block and a second function block for changing the first function block are prepared from the beginning, and a function selection block is provided for setting which function block is to be selected in the nonvolatile element. In this configuration, the function block after the change is incorporated from the beginning, so that the chip area is increased and the speed is reduced due to the provision of the function selection block for selecting the function block. Further, as a semiconductor device having selectable circuit elements, there is one described in Japanese Patent Application Laid-Open No. 8-204136. This is to select characteristics and functions of circuit elements by selectively bonding adjacent divided pads, but is not applied to a large-scale device with a high degree of integration.

As described above, a high-integration large-scale device chip used in an MCM in which it is desired to be able to change or add a functional block generally has a high development cost, and therefore has a large impact when a circuit is changed. Furthermore, in the case of MCM, a high-density mounting substrate such as ceramic or silicon is used, so the impact of changing the circuit of one chip is as follows:
Even the change of expensive MCM substrate, the development cost becomes huge. That is, in order to change the circuit of one chip used in the MCM, it is necessary to change the entire substrate, and the development cost becomes enormous. Therefore, MC
It was difficult to change the circuit easily in M.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to enable a semiconductor device having a plurality of function blocks to easily change at least one function block to a function block having another function. Another object of the present invention is to make it possible to easily add at least one functional block to a semiconductor device having at least one functional block. Further, according to the present invention, in a semiconductor device having a plurality of function blocks, at least one function block can be changed to a function block having another function, and at least one function block can be added. The task is to

Another object of the present invention is to make it possible to change or add a function only by bonding a chip of an additional function block to a predetermined portion of a substrate. Another object of the present invention is to automatically disconnect a wiring of a function block before change or a part to be added when a function is changed or added, and to operate an additional function chip instead. And

[0009]

The present invention (claim 1) comprises a substrate (1 in FIGS. 1 to 5) and a plurality of functional blocks (FIG. 1 to FIG. 1) formed on the substrate and having predetermined functions. FIG.
2 and 3), and an external circuit (13 in FIGS. 1 to 5) that connects the respective functional blocks and forms a circuit on the substrate.
And a separating unit (4 in FIGS. 1 to 3; 4 in FIGS. 4 to 5) for electrically separating a functional block that stops functioning when a function is changed (hereinafter referred to as a pre-change functional block) from the external circuit. 17 to 19) and connecting means (FIG. 1 to FIG. 3) for connecting a chip of a functional block to be added (referred to as 8 in FIGS. No. 5; 18 in FIGS. 4 and 5)
When the function is changed, the additional function chip (8) is connected to the external circuit by the connection means, and the function block before change is separated from the external circuit by the separation means. Semiconductor device.

In the above configuration, when the function is not changed, the additional function chip is not used and the function block before the change is kept effective. On the other hand, when the function is changed, the function of the pre-change function block is separated from the external circuit by the separating means and invalidated, and at the same time, the additional function chip is connected by the connecting means to perform the function. According to the present invention, an existing function block can be easily changed to a function block of a new function.

The present invention (Claim 2) provides a substrate (FIG. 6).
7 to 21; 41 in FIG. 8; 70 in FIGS. 9 to 10);
At least one functional block (22 in FIGS. 6 and 7; 42 in FIG. 8) having a predetermined function formed on the substrate and an external circuit (42) that connects the functional blocks and forms a circuit on the substrate 6 to 7; 68 and 69 in FIG. 8; FIG.
10 to 74; and a bypass wiring (23 in FIGS. 6 to 7; 43 in FIG. 8; FIG. 9 to FIG. 10) inserted into the external circuit.
71) and a separating means (FIGS. 6 and 7) for electrically separating the bypass wiring from an external circuit when adding a function.
24, 26, 27, 34, 35;
58, 63 to 66; 75 in FIGS. 9 to 10, and an additional function chip (28 in FIGS. 6 to 7; 45 in FIG. 8; 45 in FIG. 9; 76 in FIG. 9; 80) (25, 29 in FIGS. 6 to 7; 46, 47, 48, 49, 61, 62 in FIG. 8; 7 in FIG. 9).
3, 77; 73, 82, 83 in FIG. 10), and when adding a function, the additional function chip (28; 45)
Is connected to an external circuit by the connecting means, and the bypass wiring is separated from the external circuit by the separating means.

In the above configuration, when the function is not added, the additional function chip is not used, and the portion where the additional function chip is mounted is connected by the bypass wiring. On the other hand, when adding a function, the bypass wiring is separated from the external circuit by the separating means to disable the bypass function, and at the same time, the additional function chip is connected by the connecting means to enable the additional function chip. According to the present invention, it is possible to easily add a functional block.

Further, the present invention (claim 3) provides a substrate (FIG. 1)
1 and 91) and at least one functional block (92 and 93 in FIG. 11) formed on the substrate and having a predetermined function.
And an external circuit (110, 111 in FIG. 11) that connects the functional blocks and forms a circuit on the board; and a pre-change functional block that stops functioning when a function is changed among the functional blocks is electrically connected to the external circuit. A first separating means (97, 98 in FIG. 11) for separating the circuit and a first additional function chip (102 in FIG. 11) provided near the function block before change and added at the time of function change are connected. Connecting means (95, 96 in FIG. 11) and an arbitrary functional block formed on the substrate.
The bypass wiring (9 in FIG. 11) connected in the external circuit
4), a second separating means (101 in FIG. 11) for electrically separating the bypass wiring from an external circuit when adding a function, and a second separating means provided near the bypass wiring to be added when a function is added. The second additional function chip (10 in FIG. 11)
5) second connecting means (99 in FIG. 11;
100). Then, when the function is changed, the first additional function chip (102)
Is connected to the external circuit by the first connection means, and the function block before change is separated from the external circuit by the first separation means. When adding features,
The second additional function chip (105) is connected to an external circuit by the second connecting means, and the bypass wiring is separated from the external circuit by the second separating means.

According to the present invention, in the above configuration, when neither the function is changed nor the function is added, the first and second functions are provided.
No additional function chip is used, and the pre-change function block is kept valid and the bypass wiring is kept valid. When the function is changed, the function of the pre-change function block is separated from the external circuit by the first separating unit and invalidated, and at the same time, the first additional function chip is connected by the first connecting unit and the first connecting unit is connected. Enable additional function chip functions. In this case, the second additional function chip is not connected, and the second separating means maintains the bypass wiring in an effective state. When adding a function, the bypass wiring is disconnected from the external circuit by the second separating means and disabled, and at the same time, the second additional function chip is connected by the second connecting means and the second additional function chip is connected. Enable the function. At this time, the first additional function chip is not connected, and the first separating unit maintains the pre-change function block in a valid state. According to the present invention, since the before-change function block and the bypass wiring are arranged so as to overlap the same area, the area occupied by the bypass wiring area when the function is not added is the before-change function block or the first additional function chip. , The semiconductor device can be configured more compactly.

In one aspect of each of the above inventions, the connecting means may be in the vicinity of the pre-change functional block (3 in FIGS. 1 and 2) or the bypass wiring (2 in FIGS. 6 and 7).
3; pads (5; 18; 25 in FIGS. 1 and 2) formed near 43 in FIG. 8 and bumps (9 in FIGS. 1 and 2; FIGS. 6-7 2
9), the additional function chip is connected by joining the pad and the bump. According to this aspect, the function can be changed or added only by bonding the additional function chip.

In another embodiment of the present invention, the separating means is a semiconductor switch means (FIG. 1) which is set to a conductive state or a non-conductive state by a control signal applied to a control terminal.
4 of FIG. 2; 24) of FIGS. 6 and 7, and control means for supplying a control signal to the semiconductor switch means.
The control means includes a pair of electrodes (FIGS.
6 and 7 in FIG. 2; 26 and 27 in FIGS. 6 to 7), and a short-circuit electrode provided in the additional function chip and short-circuiting the pair of electrodes when the additional function chip is connected to a specific function block (FIG. 1-2 of 10, 11, and 12; 3 of FIGS. 6 and 7
0, 31, 32), a high potential source (14; 34) connected to one of the pair of electrodes (6 in FIGS. 1 and 2; 26 in FIGS. 6 to 7), and the other input side. 6 (FIGS. 1 and 2; 27 of FIGS. 6 and 7) and a pull-down buffer means (15 of FIGS. 1; 35 of FIGS. 6 and 7) whose output side is connected to the control terminal of the semiconductor switch. ).
In this configuration, when the additional function chip is not bonded, since the pair of electrodes is open, the input side of the pull-down buffer means has a low potential due to the pull-down resistor. Therefore, the control signal generated at the output side of the pull-down buffer means makes the low enable semiconductor switch conductive. When the additional function chip is joined, since the pair of electrodes is short-circuited by the short-circuit electrode, the potential from the high potential source is input to the pull-down buffer means, and the control signal generated at the output side is a semiconductor switch. Is turned off. According to the aspect of the present invention, when changing or adding a function, the additional function chip is joined to a predetermined portion of the connection means of the board, thereby automatically separating the pre-change function block and the bypass wiring,
Instead, an additional function chip can be activated.

According to another aspect of the present invention, the circuit for supplying a control signal provided in the preceding functional block uses the old function before the addition of the additional function chip based on external input data, A selection control signal indicating whether to use the new function after the addition is generated. The additional function chip is also provided with a separating means for electrically separating from the connected circuit. The selection control signal controls the separation means of the specific function block and the separation means of the additional function chip, and selects either the old function or the new function. According to this aspect, even after the additional function chip is once connected, the old function can be selected, and the optimum function can be selected according to the state of the utilization device represented by the external input data.

In another embodiment of the present invention, the separating means includes a primary pad (17 in FIG. 4) provided in the pre-change function block (3 in FIG. 4) and an external circuit at a position facing the primary pad (17 in FIG. 4). The provided secondary pad (18 in FIG. 4) and wire bonding (FIG. 4) for coupling between the primary pad and the secondary pad.
Consisting of In this case, the function block before change can be separated by cutting off the wire bonding,
The additional function chip can be mounted by joining the additional function chip to the secondary pad. According to this, the separating means and the connecting means can have a simple structure.

The present invention also relates to a substrate (41 in FIG. 8; FIG. 9).
10), at least one functional chip (42 in FIG. 8) formed on the substrate and having a predetermined function, and an external circuit (42) connecting the functional chips to form a circuit on the substrate. 68, 69 in FIG. 8; 74) in FIGS. 9 to 10;
A bypass wiring (43 in FIG. 8; 71 in FIG. 9 to FIG. 10) for bypassing a region in which an additional function chip having an additional function and having an additional function is to be added on the substrate;
When adding a function, separating means for electrically separating the bypass wiring from an external circuit (44 in FIG. 8; FIGS. 9 to 1)
0, 75) and connecting means (46 to 53 in FIG. 8; 73, 77 in FIG. 9) for connecting the additional function chips (76 in FIG. 9, 80 in FIG. 10) provided near the predetermined area. ; 73, 82, 83 in FIG. 10). In the above configuration, when the function is not added, the additional function chip is not used, and the portion where the additional function chip is mounted is connected by the bypass wiring. On the other hand, when adding a function, the bypass wiring is separated from the external circuit by the separating means to disable the bypass function, and at the same time,
The additional function chip is connected by the connection means to make the additional function chip valid. According to the present invention, it is possible to easily add a functional block in a multichip module.

In another aspect of the present invention, in the multi-chip module according to the present invention, the bypass wiring is embedded in the substrate, and a die pad is formed on a surface of the area where the bypass wiring is provided with the pad. It is characterized by having been provided. According to this, since the unevenness due to the bypass wiring is not formed on the substrate surface, the die pad can be provided for the additional function chip.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) FIGS. 1 and 2 are diagrams for explaining a function-changeable semiconductor device of a first embodiment in which the present invention is applied to an MCM-D (silicon substrate), and FIG. FIG. 2 is a side view and FIG. 2 is a plan view. This semiconductor device is configured as a multi-chip module by forming a plurality of functional blocks 2 and 3 on a silicon substrate 1 and forming wirings 13 for inputting / outputting signals and supplying power between them. I have. The functional blocks 2 and 3 are formed by a normal process technology of a semiconductor device. Among the function blocks, for the function block 3 that may change the function,
A means for changing the function is added. The function change is performed by disconnecting the electrical connection of the function block 3 formed on the silicon substrate 1 from the wiring 13 so that the changed function chip 8 having the function after the change can be inserted instead. As a mechanism for this, a three-state buffer 4 for cutting input / output signals is built in the input unit and the output unit of the function block 3 that has the old function. Here, the reason why the three-state buffer 4 is added to both the input unit and the output unit is to suppress power due to operation of unnecessary circuits. A pad 5 is provided in the vicinity of the three-state buffer 4, and when the change function chip is mounted, the pad 5 is detected.
Pads 6 and 7 for supplying a control signal (non-enable signal) are provided. When the change function chip 8 is not bonded, a low-level enable signal is supplied to the three-state buffer 4.
To enable the signal from the wiring 13 to pass therethrough. On the other hand, when the function-changing chip 8 is adhered to change the function, a high-level non-enable signal is supplied so that the signal from the wiring 13 is supplied. The passage through the three-state buffer 4 is prevented. A pull-down input buffer 15 is used so that a low-level signal can be supplied to the three-state buffer 4.

The changed function chip (additional function chip) 8 added when the function is changed is a flip chip on which the function after the change is formed, and bumps 9 are formed at positions corresponding to the pads 5 on the silicon substrate 1. The bump 1 is located at a position on the chip 3 of the changed function block corresponding to the pads 6 and 7.
0 and 11 are formed. Further, a short-circuiting wire 12 for short-circuiting between the bumps 10 and 11 is provided.
Since the chip surface is covered with a protective film (passivation), the flatness of the chip surface (the surface on which the transistor is built) is impaired. Therefore, if the flat surface of the new changed function chip is to be bonded as it is, the adhesiveness will be poor. In order to avoid this, the present embodiment uses flip chip mounting. When the function block 3 first formed on the silicon substrate 1 is used as it is without using the change function chip 8, since the short-circuit wire 12 is not short-circuited between the pads 6 and 7, the pull-down input buffer 15 The output is at a low level, and the three-state buffer 4 controlled by the output is in a signal passable state, and the functional block 3 is activated.

When the function is to be changed, the changed function chip 8 is connected to the bump 9 by the pad 5 and the bump 10 by the pad 6.
Then, the bumps 11 are joined so as to match the pads 7 respectively. Then, a high-level voltage signal VDD is supplied to the pull-down input buffer 15 via the pad 6, the bump 10, the short-circuit wire 12, and the bump 11, and therefore, the control signal supplied from the pull-down input buffer 15 to the control electrode of the three-state buffer 4 is The potential becomes a high level, the 3-state buffer 4 becomes non-conductive, and the functional block 3
Is disconnected from the wiring 13. The changed function chip 8 is connected to the wiring 13 by the bump 9 being connected to the pad 5.
And operates in place of the function block 3.

According to this embodiment, the ASI can be performed without using a programmable device such as a PLD or an FPGA.
The function can be changed in a highly integrated device such as C. Further, by making the package a cavity structure, it is also possible to change the function of the chip built in the already completed package. Further, according to this embodiment, the three-state buffer 4 is turned off by joining the modified function chip 8 to the substrate, and the function block 3
Is separated from the circuit, so that the operation for changing the function is simplified. At that time, it is not necessary to physically remove the functional block 3 from the substrate, and the functional block 3 may be left in the substrate, so that the reliability is not reduced due to the function changing operation.

In this embodiment, the control unit of the three-state buffer 4 uses a high-level potential VDD input at the time of bonding the changeable function chip and a control signal generating means using the pull-down input buffer 15, as shown in FIG. Alternatively, a configuration may be employed in which a three-state buffer control unit is provided in a function block in the preceding stage. In this case, after the changed function chip is once adhered, the old function and the new function block can be selectively used depending on externally input data. For example, when implemented in a copier, the priority can be given to speed and image quality can be degraded, and vice versa by changing whether bypass wiring is separated by external input data. It is possible to selectively determine whether to use the chip or to use the pre-change function block. In FIG. 3, input image data is fetched from the terminal 301 and is operated by the three-state buffer control logic 16 to determine whether to use the old function or the new function. When the old function is used, a low-level signal is output to the function block 3 so that the terminals 303 and 30 are output.
7. When a low-level voltage is applied to the control terminal of the three-state buffer 4 via the short-circuit conductor 311, the bump 308, and the pad 304, the functional block 3 is enabled. On the other hand, the signal of the pad 304 is
05, a high level voltage is applied to the pad 306,
3 provided on the change function chip 312 via the bump 109
The function block is provided to the state buffer 310, and the function block of the function change chip enters the non-enabled state. When the new function is used, a high-level signal is output to the function block 3 so that the high-level signal is output to the control terminal of the three-state buffer 4 via the terminals 303 and 307, the short-circuiting wire 311, the bump 308, and the pad 304. When the voltage is applied, the function block 3 enters the non-enabled state. On the other hand, the signal of the pad 304 is inverted by the inverter 305 and a low level voltage is supplied to the three-state buffer 31 provided on the change function chip 312 via the pad 306 and the bump 309.
0, the function block of the function change chip is enabled, and a new function is selected.

The signal supplied to the control electrode of the three-state buffer 4 is not automatically supplied by the mounting of the changing function chip 8 as described above. Wire bonding is performed so that the VSS voltage is supplied to the pad connected to the control electrode of the buffer 4, and when the change function chip 8 is bonded, the VDD voltage is supplied to the pad connected to the control electrode of the three-state buffer 4. Wire bonding may be performed.

(Second Embodiment) FIGS. 4 and 5 show an MCM.
FIG. 4 is a diagram for explaining a semiconductor device capable of changing functions according to a second embodiment in which the present invention is applied to a -D (silicon substrate), FIG. 4 is a side view, and FIG. 5 is a plan view. In the figure, the same reference numerals are used for the same or corresponding elements as in the first embodiment.

This semiconductor device is formed by forming a plurality of functional blocks 2 and 3 on a silicon substrate 1 and forming a wiring 13 for inputting / outputting signals and supplying power to the functional blocks. For the functional block 3 which may perform the function, a means for performing a function change is added.
The purpose of performing the function change by disconnecting the electrical connection of the function block 3 formed on the silicon substrate 1 from the wiring 13 and inserting the changed function chip 8 having the function after the change instead. Although the second embodiment is the same as the first embodiment, the configuration of the means for changing its function is different from that of the first embodiment.

In the second embodiment, the primary block 1 is provided at the input / output end of the functional block 3 where the function may be changed.
7 are formed, and a secondary pad 18 is
Is formed, and the primary pad 17 and the secondary pad 18 can be connected by wire bonding.

In order to use the functional block 3, the primary pad 17 and the secondary pad 18 are connected by wire bonding 19. As a result, an electrical connection with the wiring 13 is established, input / output signals and power can be supplied, and the circuit is connected to another circuit such as another functional block 2.

Changed function chip 8 mounted at the time of function change
Is a flip-chip mounting in which functions after the change are formed, and bumps 9 are formed at positions corresponding to the pads 18 on the silicon substrate 1.

When it becomes necessary to change the function of the function block 3, first, the function block 3 is separated from the circuit on the board by cutting off the wire 19, and the function before change is invalidated. Next, the modified function chip 8 is bonded so that the bumps 9 match the secondary pads 18. Since the chip surface is covered with a protective film (passivation), the flatness of the chip surface (the surface on which the transistor is built) is impaired. Therefore, if the flat surface of a new chip is to be bonded as it is, the adhesiveness will be poor. In order to avoid this, the present embodiment uses flip chip mounting.

In the second embodiment, similarly to the first embodiment, the function can be changed in a highly integrated device such as an ASIC without using a programmable device such as a PLD or an FPGA. .

(Third Embodiment) FIGS. 6 and 7 show an MCM.
FIG. 6 is a diagram for explaining a semiconductor device capable of adding functions according to a third embodiment in which the present invention is applied to −D, FIG. 6 is a side view,
FIG. 7 is a plan view.

In the semiconductor device of this embodiment, a plurality of functional blocks 22 (only one is shown) are formed on a silicon substrate 21 and circuit wiring for inputting / outputting signals and supplying power is formed between them. 33 are formed. A means for adding a function is added to a function addable area on the silicon substrate 21 where a function can be added. The addition of the function is performed by cutting off the electrical connection when the function is not added to the function addable region formed on the silicon substrate 21 and inserting the additional function chip 28 having the additional function at the cut portion in series. Do. The wiring that is electrically connected when the function addition is not performed in the function addition possible area is referred to as a bypass wiring 23. In the bypass wiring 23, a three-state buffer 24 is provided to make the electrical connection conductive when the function is not added and to make the electrical connection non-conductive when the function is added. Also,
In the area where functions can be added, pads 25 are provided, and pads 26 and 27 for detecting that the change function chip 28 is mounted and supplying a control signal (non-enable signal) to the three-state buffer 24 are provided. When the additional function chip 28 is not bonded, a low-level enable signal is supplied to the enable control terminal of the three-state buffer 24 to allow the signal from the wiring 33 to pass, while the additional function chip 28 is bonded to add the function. In this case, a high-level non-enable signal is supplied to prevent the signal from the wiring 33 from passing through the three-state buffer 24.
A pull-down input buffer 35 is used so that a low-level signal can be supplied to the three-state buffer 24.

Additional function chip 2 to be attached when adding a function
Reference numeral 8 denotes a flip-chip mounting in which functions after the addition are formed. A bump 29 is formed at a position corresponding to the pad 25 on the silicon substrate 21, and bumps 30 and 31 are formed at positions corresponding to the pads 26 and 27. Have been. Further, a short-circuiting conductor 32 for short-circuiting between the bumps 30 and 31 is provided.

When the additional function chip 28 is not used,
Since the additional function chip 28 is not bonded, the pad 26,
27, no short-circuit is caused by the short-circuit conductor 12 of the additional function chip 28, so that the pull-down input buffer 15
Is at a low level, and the three-state buffer 24 controlled thereby is in a signal passable state. Therefore,
The bypass circuit 23 forms a bypass circuit.

In order to add a function, the additional function chip 28 is bonded so that the bump 29 matches the pad 25, the bump 30 matches the pad 26, and the bump 31 matches the pad 27. Then, the high-level voltage signal VDD
Are pads 26, bumps 30, short-circuiting wires 32, bumps 31
, The control signal applied from the pull-down input buffer 35 to the control electrode of the 3-state buffer 24 becomes a high-level potential, and the 3-state buffer 24 becomes non-conductive.
The bypass wiring 23 stops the bypass function. And
The additional function chip 28 is connected to the wiring 13 by coupling the bump 29 to the pad 25, and the function is added.

According to this embodiment, even a device that can be highly integrated can flexibly cope with the addition of a circuit function.
Further, according to this embodiment, the three-state buffer 4 is turned off and the bypass wiring 23 is made invalid by joining the additional function chip 8 to the substrate, so that the work for adding a function is simplified. , Reliability is improved.

(Fourth Embodiment) FIG. 8 shows a fourth embodiment in which the present invention is applied to a high-density mounting board (other than MCM-D), in which chips of additional function blocks are connected by wire bonding. At the same time, a bypass wiring is formed of discrete components on a substrate, and a part of a control unit for controlling a three-state buffer for turning on / off an electrical connection of the bypass wiring is provided in a preceding functional block. .
It should be noted that the bypass wiring portion may be formed in the functional block chip 42 instead of being formed of discrete components.

On the high-density mounting board, secondary pads 46, 47, 52, 53 for connecting the chip 42 of the functional block, the chip 45 of the additional functional block, and the bypass wiring portion 43 are formed. In the functional block chip 42, an input buffer 56 for pull-down is built in as a part of a control circuit for controlling the three-state buffer 44 of the bypass wiring part 43, and another circuit part (external circuit) on the substrate is provided. Circuit) and bonding wires 65, 66, 67
Pads 55 and 57 for making electrical connection by
60 are formed. Opposite thereto, secondary pads 54, 58, 59 are provided on the substrate. These one
Bonding wires 65, 6 between the secondary pad and the secondary pad
6 and 67. Additional function block chip 4
5 is provided with primary pads 48, 49, 50, 51.
A bypass wiring portion 43 is formed by a discrete component in a region different from the region where the additional function block is bonded. A three-state buffer 44 for turning on and off the bypass circuit is connected in series to the bypass wiring.

When the additional function is not used, the bonding wire 6 is connected between the primary pads 55, 57, 60 of the functional block chip 42 and the secondary pads 54, 58, 59 on the substrate.
Connections are made at 5, 66 and 67. The output of the function block 42 is connected to another function block chip (not shown) via the bypass wiring section 43. In this connection state, the input of the pull-down input buffer 56 is at a low level, and a low-level voltage is applied to the control terminal of the three-state buffer 44, so that the three-state buffer 44 is enabled and bypasses the scheduled area of the additional function block chip. Then, connection to another functional block chip is made.

When the additional function block chip 45 is used, the additional function block chip 45 is bonded to the substrate by wire bonding or flip chip mounting. In the case of wire bonding, the primary pads 48, 49, 50, and 5 are used.
1 are the secondary pads 46, 47, 52, 5 on the substrate, respectively.
3 and bonding wires 61, 62, 63, 64. In this connection state, the high-level potential VDD from the pad 52 is supplied to the pull-down input buffer 56 via a bonding wire or wiring. The output of the pull-down input buffer 56 is connected to the third
Since a high potential is applied to the control terminal of the state buffer 44, the three-state buffer 44 is turned off and the bypass circuit does not function. Instead, the connected additional function block chip 45 is added.

According to this embodiment, additional function blocks can be easily added by pad bonding and wire bonding (or flip chip mounting), and switching to bypass wiring can be automatically performed.

(Fifth Embodiment) FIG. 9 shows another example of adding a functional block chip in the MCM, and shows a configuration of a bypass wiring and a procedure for adding a function. The bypass wiring 71 is embedded in the substrate 70, and both ends thereof are connected to primary pads 72 formed on the surface of the substrate. When the additional function block is not mounted, as shown in FIG.
3 are connected by a bonding wire 75 to make the bypass wiring effective.

When an additional function block is added to the semiconductor device used for the bypass wiring, first, the bonding wire 75 in the bypass wiring is cut off. Then, as shown in FIG. 9C, the additional function block 76 of flip-chip mounting is die-attached, and as shown in FIG. 9D, the bypass wiring is cut off from the circuit, and the chip 76 of the additional function block is added. State. According to this embodiment, the structure is simple because the separation part for switching the bypass wiring is wine bonding.

Here, a specific advantage obtained by enabling the function addition will be described with reference to an example of FIG. 13 to which the fifth embodiment is applied. FIG. 14 (a) shows a conventional MCM substrate design.
An output signal cannot be obtained as shown in FIG. 14C unless one of the three-chip MCMs is mounted as in the example shown in FIG. Therefore, all colors requiring the page memory 1411 as shown in FIG.
FIG. 14 shows a case where serial conversion processing is performed by two MCMs.
Using one MCM for each color as shown in (b),
In parallel processing, the MCM to be used had to be separately designed and manufactured, and the development cost and the manufacturing cost had to be relatively high. On the other hand, FIG.
In the specific example of the present invention shown in FIG.
Since the bypass wiring can be inserted at the position where the first chip is arranged, an output signal can be obtained by utilizing the bypass wiring even when there is no first chip. Therefore, FIG.
FIG. 13A illustrates a case where all colors requiring the page memory 1311 are serially converted by one MCM, and FIG. 13B illustrates a case where parallel processing is performed using one MCM for each color. An MCM substrate to be used can be used in common with the case of processing, and development costs and manufacturing costs can be significantly reduced.

(Sixth Embodiment) FIG. 10 shows still another example in which a function block chip is added to the MCM. In the fifth embodiment (FIG. 9), an additional function block is added by die attach. This is an example of attachment. In the figure, the same parts as those in the fifth embodiment are denoted by the same reference numerals, and description thereof will be omitted. A die pad 81 for applying a substrate potential is provided to the additional function block 80, a primary pad 82 is formed on the upper surface of the additional function block 80, and the secondary pad 73 is connected to the secondary pad 73 by a bonding wire 83.
According to this embodiment, the die pad 81 and the bypass wiring 7
1 is not short-circuited, and additional functions can be easily added simply by arranging the additional function block 80 and performing normal wire bonding.

(Seventh Embodiment) The seventh embodiment shows an embodiment of a semiconductor device capable of performing either one of changing a function and adding a function. The means for changing and the means for adding the function of the third embodiment are connected, and the regions where the chips for changing or adding are joined are overlapped. FIG. 11 shows an example of a configuration in which a function adding unit having a bypass wiring is connected at a stage subsequent to a function block 93 having a function changing unit, and FIG. 12 shows a case where a function adding unit is connected at a stage subsequent to another arbitrary fixed function block 115. The example of a structure is shown. In the example of the semiconductor device shown in FIG. 11A, a plurality of functional blocks 92, 9 are provided on a silicon substrate 91.
3 are formed, and a wiring is provided between them. Among the function blocks, means for performing a function change and a function addition are added to a function block 93 that may change or add a function. The function change is performed by the function block 9 formed on the silicon substrate 91.
3 by disconnecting the electrical connection from the external circuit so that the changed function chip 102 having the function after the change can be inserted instead. As a mechanism for this, a three-state buffer 9 for cutting input / output signals at the input and output of the functional block 93 that is an old function
7, 98 are made. When the change function chip 102 is used without being joined, the three-state buffers 97 and 98 are used.
Is turned on, the functional block 93 is activated. On the other hand, when the function is changed, FIG.
As shown in (b), the bump 1 of the changed function chip 102
03 and 104 are aligned and bonded to the secondary pads 95 and 96, and the three-state buffers 97 and 98 are turned off to disconnect the functional block 93 from the external circuit, thereby activating the changed function chip 102. I do.

A means for adding a function is added to a function addable area on the silicon substrate 91 where a function can be added. The function-addable area substantially overlaps the function-changeable area in position. Therefore, function addition and function change cannot be performed simultaneously. For additional functions,
This is performed by disconnecting the electrical connection of the function-addable region formed on the silicon substrate 91 when the function is not added and inserting the additional function chip 105 having the additional function at the cut portion in series. In the bypass wiring 94, a three-state buffer 101 is provided to make the electrical connection conductive when the function is not added, and to make the electrical connection non-conductive when the function is added. When the additional function chip 105 is used without being joined, the bypass wiring section 94 forms a bypass circuit by turning on the three-state buffer 101. On the other hand, when adding a function, as shown in FIG. 11C, the bumps 106 and 107 of the additional function chip 105 are
00 and joined to form a three-state buffer 10
By setting 1 to a non-conductive state, the additional function chip 105 is connected instead of the bypass wiring 94. Note that the control of the three-state buffers 97, 98, and 101 may be performed by using the same control method as that of the three-state buffers of the first and third embodiments, and thus the description is omitted here.

In the example of FIG. 11A, the function adding means having the bypass wiring is the function block 9 having the function changing means.
3 is electrically connected at the subsequent stage.
As shown in FIG. 11A, the installation area is the same as in FIG. 11, and the electrical connection can be made to connect to another fixed function block 115. FIG. 12A,
3B schematically shows a cross-sectional structure, in which wirings and detailed structures in the functional block formed on the upper surface of the functional block 93 are omitted. The function adding means having the bypass wiring is not limited to the case where it is superimposed on the area of the function block 93 to be changed as shown in FIG. 11A or FIG. May be installed so as to overlap the area of any fixed function block.

According to this embodiment, since the function block before the change and the function adding means having the bypass wiring are arranged so as to overlap the same area, the bypass wiring area occupies one functional block when the function is not added. Is effectively used for connecting the pre-change function block or the change function chip, so that the semiconductor device can be configured more compactly. The same effect can be obtained even when an arbitrary fixed function block and a function adding unit having a bypass wiring are arranged so as to overlap in the same region.

[0053]

According to the present invention, in a semiconductor device having a plurality of function blocks, separating means for separating the specific function block from an external circuit in the substrate is provided near at least one specific function block; Since the connection means for connecting the additional function chip which substitutes for the specific function block is provided, the function block can be easily changed. Therefore, it is not necessary to change the entire substrate to change the function of a part of the semiconductor device as in the related art, and the development cost required for the change can be greatly reduced. Further, according to the present invention, instead of developing and manufacturing a plurality of semiconductor devices in which the functions of some of the functional blocks are different and the functions of the remaining functional blocks are common to each other, some of the functional blocks are By making them changeable, they can be developed in common and manufactured in the same process, so that development costs and manufacturing costs can be reduced and reliability can be improved. Further, according to the present invention, the function is changed by electrically separating the specific function block and connecting an additional function chip instead, but it is necessary to physically remove the specific function block from the substrate. Since there is no function change process, the function change process is simple, and the reliability does not decrease due to the function change.

According to the present invention, in a semiconductor device having at least one functional block, a separating means for separating a bypass wiring when adding a function and a connection for an additional function chip provided near the bypass wiring. With the means, functional blocks can be easily added. Therefore, it is not necessary to change the entire substrate to add a function to the semiconductor device as in the related art, and it is possible to greatly reduce the development cost required for the change.
According to the present invention, a semiconductor device having only a common function without an additional function chip and a semiconductor device to which the additional function chip is connected are not developed and manufactured, but new function blocks are added. By making it possible,
Since they can be developed in common and manufactured in the same process, development costs and manufacturing costs can be reduced, and reliability can be improved.

Further, according to the present invention, in a semiconductor device having a plurality of function blocks, at least one function block is provided with another function by providing separation means and connection means for function change and function addition, respectively. The function block can be changed to a function block having the function block, and at least one function block can be added. At this time, since the pre-change function block and the bypass wiring are arranged so as to overlap with the same area, the area of one function block occupied by the bypass wiring area when the function is not added is the pre-change function block or the change function. It can be effectively used by connecting the chips, and the semiconductor device can be configured more compactly.

Further, in the present invention, the connection means joins a pad formed in the vicinity of a specific function block or the bypass wiring which stops functioning when the function is changed, and a bump formed on a corresponding additional function chip. In such a configuration, it is extremely easy to change or add functions.

In the present invention, when the bypass wiring is buried in the substrate and the die pad is provided on the surface of the area where the bypass wiring is provided with the connection pad, the unevenness due to the bypass wiring is reduced. Since it is not formed on the substrate surface, a die pad for an additional function chip can be provided. Also, there is no short circuit between the bypass wiring and the die pad.

Further, in the present invention, the separating means is constituted by a semiconductor switch means and a control means for controlling on / off of the semiconductor switch means, and the control means is adapted to generate an appropriate control signal depending on whether or not the additional function chip is mounted. In this case, when the function is changed or added, the wiring of the function block before the change or the part to be added is automatically cut off, and the additional function chip can be operated instead. It should be noted that the control means may be provided in the preceding functional block. At that time, based on the external input data, a selection control signal indicating whether to use the old function before adding the additional function chip or to use the new function after addition is generated, and the additional function chip is also provided with the separating means. Is provided, and if any of the old function and the new function is selected by the selection control signal, even after the additional function chip is once connected,
The old function can be selected, and the optimum function can be selected according to the state of the utilization device represented by the external input data.

Also, in the present invention, the separating means includes a primary pad provided in a specific functional block, a secondary pad provided on an external circuit at a position opposed to the primary pad, and a connection between the primary pad and the secondary pad. In the case of using wire bonding for connection, there is an advantage that the structure for separation is simple.

[Brief description of the drawings]

FIG. 1 is a side view showing a function-changeable semiconductor device according to a first embodiment;

FIG. 2 is a plan view showing a semiconductor device capable of changing functions according to the first embodiment;

FIG. 3 is a diagram showing a modification in which a part of the first embodiment is changed;

FIG. 4 is a side view showing a semiconductor device capable of changing functions according to the second embodiment;

FIG. 5 is a side view showing a semiconductor device capable of changing functions according to the second embodiment;

FIG. 6 is a side view showing a semiconductor device capable of adding functions according to the third embodiment;

FIG. 7 is a side view showing a semiconductor device capable of adding functions according to the third embodiment;

FIG. 8 is a diagram showing a semiconductor device capable of adding functions according to a fourth embodiment;

FIG. 9 is a diagram showing a semiconductor device capable of adding functions according to a fifth embodiment;

FIG. 10 is a diagram showing a semiconductor device capable of adding functions according to a sixth embodiment;

FIGS. 11A and 11B are schematic views showing a semiconductor device capable of changing or adding functions according to the seventh embodiment, wherein FIG.
(B) is an AA ′ cross-sectional view, and (c) is a BB ′ cross-sectional view.

FIG. 12 is an example in which a part of the seventh embodiment is changed, and FIG.
Is a plan view, (b) is a cross-sectional view along AA ', and (c) is a BB'.
Sectional view,

FIG. 13 is a view showing a specific example for explaining the effect of the present invention,

FIG. 14 is a diagram for explaining a conventional technique;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Silicon substrate, 2-3 ... Function block, 4 ... 3-state buffer, 5-11 ... Pad, 8 ... Additional function chip which has a function after change, 12 ... Short-circuit wire, 14 ... VDD terminal, 15 ... Pull-down input buffer .

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H05K 1/02 1/18

Claims (11)

[Claims] 1. A substrate, a plurality of functional blocks formed on the substrate and having a predetermined function, an external circuit connecting the functional blocks to form a circuit on the substrate, and a function among the functional blocks Separating means for electrically separating a specific function block that stops functioning when changing from an external circuit; and connecting means for connecting an additional function chip provided near the specific function block and having a function block added when changing the function A semiconductor device, wherein when the function is changed, the additional function chip is connected to the external circuit by the connection means, and the specific function block is separated from the external circuit by the separation means. apparatus. 2. A board, at least one function block having a predetermined function formed on the board, an external circuit connecting the respective function blocks to form a circuit on the board, and being inserted into the external circuit. And a bypass line for bypassing a region where an additional function chip having an additional function is to be added on the substrate, and a separating unit for electrically separating the bypass line from an external circuit when adding a function, Connecting means for connecting an additional function chip having a function block to be added, provided with the bypass wiring, and connecting the additional function chip to an external circuit by the connecting means when adding a function; A semiconductor device, wherein the bypass line is separated from the external circuit by the separating means. 3. A substrate, at least one functional block formed on the substrate and having a predetermined function, an external circuit connecting the functional blocks and forming a circuit on the substrate, A first separating unit for electrically separating a specific function block that stops functioning when a function is changed from an external circuit, a first additional function that is provided in an input / output unit of the specific function block and is added when the function is changed A first connection unit for connecting a chip, a bypass wiring laid over the upper part of an area of an arbitrary functional block formed on the substrate and connected to the external circuit, A second separating means for electrically separating the bypass wiring from an external circuit; and a second additional function chip provided at an input / output unit of the bypass wiring and added when a function is added. And a second connection unit for connecting the first additional function chip to the external circuit by the first connection unit when the function is changed, When the specific function block is separated from the external circuit by the means and the function is added, the second chip is connected to the external circuit by the second connection means, and the bypass wiring is connected by the second separation means. A semiconductor device, wherein the semiconductor device is separated from the external circuit. 4. The connection means has a pad formed on an input / output portion of the specific function block or the bypass wiring which stops functioning when the function is changed, and a bump formed on the additional function chip corresponding thereto. 4. The semiconductor device according to claim 1, wherein the additional function chip is connected by bonding the pad and the bump. 5. The semiconductor device according to claim 1, wherein the separation unit includes a semiconductor switch unit that is set to a conductive state or a non-conductive state by a control signal applied to a control terminal, and a control unit that supplies a control signal to the semiconductor switch unit. The control means includes a pair of electrodes provided on the substrate, a short-circuit electrode provided on the additional function chip, and a short-circuit electrode for short-circuiting the pair of electrodes when the additional function chip is connected to a specific function block. 2. A high-potential source connected to one of the electrodes, and a pull-down buffer having an input connected to the other electrode and an output connected to a control terminal of the semiconductor switch. The semiconductor device according to claim 4. 6. The semiconductor device according to claim 1, wherein the separation unit includes a semiconductor switch unit that is set to a conductive state or a non-conductive state by a control signal applied to a control terminal, and a control unit that supplies a control signal to the semiconductor switch unit. 5. The semiconductor device according to claim 1, wherein said control means includes a circuit for supplying a control signal in a preceding functional block. 7. A circuit for supplying a control signal provided in the preceding function block uses an old function before addition of an additional function chip or uses a new function after addition based on external input data. The additional function chip is also provided with a separating means for electrically separating the connected function circuit from the connected circuit, and the separating function of the specific function block is added by the selection control signal. 7. The semiconductor device according to claim 6, wherein the separation means of the functional chip is controlled to select one of an old function and a new function. 8. The separation means includes a primary pad provided in a specific function block, a secondary pad provided on an external circuit at a position facing the primary pad, and a wire connecting the primary pad and the secondary pad. 2. The semiconductor device according to claim 1, comprising bonding. 9. A substrate, at least one function chip formed on the substrate and having a predetermined function, an external circuit connecting the function chips to form a circuit on the substrate, and being inserted into the external circuit. And a bypass line for bypassing a region where an additional function chip having an additional function is to be added on the substrate, and a separating unit for electrically separating the bypass line from an external circuit when adding a function, A connection means for connecting an additional function chip provided with the bypass wiring, and when adding a function, the additional function chip is connected to an external circuit by the connection means, and a bypass is provided by the separation means. A semiconductor device, wherein wiring is separated from the external circuit. 10. The connecting means includes a pad formed on an input / output unit in the predetermined area and a bump formed on the additional function chip corresponding thereto, and joining the pad and the bump. 10. The semiconductor device according to claim 9, wherein the connection of the additional function chip is performed by the following. 11. The device according to claim 10, wherein the bypass wiring is embedded in the substrate, and a die pad is provided on a surface of the area where the bypass wiring is provided with the pad. Semiconductor device.