semiconductor memory device

Abstract

To provide a semiconductor memory device capable of suppressing deterioration of the performance characteristics while arranging nonvolatile semiconductor elements according to a substrate.SOLUTION: A semiconductor memory device includes first and second nonvolatile semiconductor memories, a circuit element, a controller, first to third signal lines, a connector, and a substrate. The second signal line connects the circuit element and the first nonvolatile semiconductor memory to each other and includes a first via hole. The third signal line is connected to the second nonvolatile semiconductor memory by branching from the second signal line through the first via hole. The third signal line includes a second via hole. In a plan view, it is configured so that a first region in which the first via hole is provided and a second region in which the second via hole is provided do not overlap.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] FIELD Embodiments of the present invention relate to a semiconductor memory device. [Background technology]

[0002] Conventionally, semiconductor devices have been used in which nonvolatile semiconductor memory elements such as NAND flash memories are mounted on a substrate on which a connector is formed. In addition to the nonvolatile semiconductor memory elements, the semiconductor devices also have volatile semiconductor memory elements and a controller that controls the nonvolatile and volatile semiconductor memory elements.

[0003] The shape and size of the substrate of such semiconductor devices may be restricted in accordance with the environment in which they are used, standards, etc. It is therefore required to arrange nonvolatile semiconductor memory elements and the like in accordance with the shape and size of the substrate while suppressing degradation of their performance characteristics. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-79445 Summary of the Invention [Problem to be solved by the invention]

[0005] An object of one embodiment of the present invention is to provide a semiconductor memory device that can arrange nonvolatile semiconductor elements and the like in accordance with the limitations of the shape and size of a substrate while suppressing degradation of their performance characteristics. [Means for solving the problem]

[0006] According to one embodiment of the present invention, there is provided a semiconductor memory device comprising a first nonvolatile semiconductor memory, a second nonvolatile semiconductor memory, a circuit element, a controller, a first signal line, a second signal line, a third signal line, a connector, and a substrate. The circuit element has a first electrode, a second electrode, a film provided between the first electrode and the second electrode, and a film covering the film. The controller controls the first and second nonvolatile semiconductor memories. The first signal line connects the controller and the circuit element. The second signal line connects the circuit element and the first nonvolatile semiconductor memory and includes a first via hole. The third signal line branches from the second signal line by the first via hole and is connected to the second nonvolatile semiconductor memory. The connector is provided for connection to an external device. The first and second nonvolatile semiconductor memories, the circuit element, the controller, and the connector are mounted on the substrate. The substrate has a surface layer, a back layer, and multiple internal wiring layers. The surface layer has a wiring pattern formed on the surface of the substrate, and the first nonvolatile semiconductor memory and the circuit element are mounted thereon. The back layer has a wiring pattern formed on the back surface of the substrate, and the second nonvolatile semiconductor memory is mounted thereon. The multiple internal wiring layers are provided between the surface layer and the back layer, and have wiring patterns. The third signal line includes a second via hole. In a plan view, a first region in which the first via hole is provided and a second region in which the second via hole is provided are configured so as not to overlap. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a block diagram illustrating a configuration example of a semiconductor device according to a first embodiment. [Figure 2] FIG. 2 is a plan view showing a schematic configuration of the semiconductor device. [Figure 3] FIG. 3 is a plan view showing a detailed configuration of the semiconductor device. [Figure 4] FIG. 4 is a perspective view showing a schematic configuration of a resistance element. [Figure 5] FIG. 5 is a diagram showing the circuit configuration on the surface layer (first layer) of the substrate. [Figure 6] FIG. 6 is a diagram showing the circuit configuration on the back surface layer (eighth layer) of the substrate. [Figure 7] FIG. 7 is a diagram showing the configuration of wiring connecting the drive control circuit and the NAND memory, and is a conceptual diagram of the layer configuration of the substrate. [Figure 8] FIG. 8 is a bottom view showing a schematic configuration of a semiconductor device according to a first modification of the first embodiment. [Figure 9] FIG. 9 is a diagram showing the configuration of wiring connecting the drive control circuit and the NAND memory, and is a conceptual diagram of the layer configuration of the substrate. [Figure 10] FIG. 10 is a plan view showing a detailed configuration of the semiconductor device according to the second embodiment. [Figure 11] FIG. 11 is a cross-sectional view taken along the line AA shown in FIG. [Figure 12] FIG. 12 is a bottom view showing a schematic configuration of a semiconductor device according to a first modification of the second embodiment. [Figure 13] FIG. 13 is a cross-sectional view taken along the line BB shown in FIG. [Figure 14] FIG. 14 is a plan view showing a schematic configuration of a semiconductor device according to the third embodiment. [Figure 15] FIG. 15 is a diagram showing the bottom surface of the NAND memory. [Figure 16] FIG. 16 is a bottom view showing a schematic configuration of a semiconductor device according to a first modification of the third embodiment. [Figure 17] FIG. 17 is a plan view showing a schematic configuration of a semiconductor device according to the fourth embodiment. [Figure 18] FIG. 18 is a bottom view showing a schematic configuration of a semiconductor device according to a first modification of the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Semiconductor memory devices according to embodiments will be described in detail below with reference to the accompanying drawings, although the present invention is not limited to these embodiments.

[0009] (First embodiment) 1 is a block diagram showing an example of the configuration of a semiconductor device according to a first embodiment. The semiconductor device 100 is connected to a host device (hereinafter abbreviated as host) 1, such as a personal computer or a CPU core, via a memory connection interface such as a SATA interface (ATA I / F) 2, and functions as an external memory for the host 1. Examples of the host 1 include the CPU of a personal computer, and the CPU of an imaging device such as a still camera or video camera. The semiconductor device 100 can also send and receive data to and from a debugging device 200 via a communication interface 3, such as an RS232C interface (RS232C I / F).

[0010] The semiconductor device 100 includes a NAND flash memory (hereinafter abbreviated as NAND memory) 10 as a nonvolatile semiconductor memory element, a drive control circuit 4 as a controller, a DRAM 20 as a volatile semiconductor memory element capable of faster storage operations than the NAND memory 10, a power supply circuit 5, an LED 6 for displaying status, and a temperature sensor 7 for detecting the temperature inside the drive. The temperature sensor 7 measures the temperature of the NAND memory 10 directly or indirectly, for example. If the measurement result by the temperature sensor 7 exceeds a certain temperature, the drive control circuit 4 restricts writing of information to the NAND memory 10, thereby preventing further temperature rise.

[0011] The power supply circuit 5 generates a plurality of different internal DC power supply voltages from an external DC power supply supplied from the power supply circuit on the host 1 side, and supplies these internal DC power supply voltages to each circuit in the semiconductor device 100. The power supply circuit 5 also detects the rise of the external power supply, generates a power-on reset signal, and supplies it to the drive control circuit 4.

[0012] FIG. 2 is a plan view showing a schematic configuration of the semiconductor device 100. FIG. 3 is a plan view showing a detailed configuration of the semiconductor device 100. The power supply circuit 5, the DRAM 20, the drive control circuit 4, and the NAND memory 10 are mounted on a substrate 8 on which a wiring pattern is formed. The substrate 8 has a generally rectangular shape in a plan view. A connector 9 is connected to the host 1 and functions as the SATA interface 2 and the communication interface 3 described above on one short side of the generally rectangular substrate 8. The connector 9 functions as a power input unit that supplies power input from the host 1 to the power supply circuit 5. The connector 9 is, for example, an LIF connector. Note that a slit 9a is formed in the connector 9 at a position offset from the center along the short side of the substrate 8, and is adapted to fit with a protrusion (not shown) provided on the host 1. This prevents the semiconductor device 100 from being installed upside down.

[0013] The substrate 8 has a multi-layer structure formed by stacking layers of synthetic resin, for example, an eight-layer structure. The number of layers of the substrate 8 is not limited to eight. Wiring patterns of various shapes are formed on the surface or inner layer of each layer made of synthetic resin on the substrate 8. The power supply circuit 5, DRAM 20, drive control circuit 4, and NAND memory 10 mounted on the substrate 8 are electrically connected to each other via the wiring patterns formed on the substrate 8.

[0014] Next, the arrangement of the power supply circuit 5, DRAM 20, drive control circuit 4, and NAND memory 10 on the substrate 8 will be described. As shown in Figures 2 and 3, the power supply circuit 5 and DRAM 20 are arranged near the connector 9. The drive control circuit 4 is then arranged next to the power supply circuit 5 and DRAM 20. The NAND memory 10 is then arranged next to the drive control circuit 4. That is, the DRAM 20, drive control circuit 4, and NAND memory 10 are arranged in this order from the connector 9 side along the longitudinal direction of the substrate 8.

[0015] A plurality of NAND memories 10 are mounted on the substrate 8, and these NAND memories 10 are arranged side by side along the longitudinal direction of the substrate 8. In the first embodiment, four NAND memories 10 are arranged, but the number of NAND memories 10 to be mounted is not limited to this as long as a plurality of NAND memories 10 are arranged.

[0016] Of the four NAND memories 10, two NAND memories 10 are arranged close to one long side of the substrate 8, and the remaining two NAND memories 10 are arranged close to the other long side of the substrate 8.

[0017] Furthermore, a resistive element 12 is mounted on the substrate 8. The resistive element 12 is provided in the middle of a wiring pattern (wiring) connecting the drive control circuit 4 and the NAND memory 10, and functions as a resistor for signals input / output to / from the NAND memory 10. FIG. 4 is a perspective view showing a schematic configuration of the resistive element 12. As shown in FIG. 4, the resistive element 12 is configured by covering a plurality of resistive films 12a provided between electrodes 12c with a protective film 12b. One resistive element 12 is provided for one NAND memory 10. Each resistive element 12 is disposed near the NAND memory 10 connected to that resistive element 12.

[0018] Next, the wiring pattern formed on the substrate 8 will be described. As shown in Fig. 3, there is an area S between the power supply circuit 5 and the drive control circuit 4 where almost no electronic components are mounted. In area S of the substrate 8, signal lines (SATA signal lines) that connect the connector 9 and the drive control circuit 4 are formed as part of the wiring pattern. In this way, on the substrate 8, the SATA signal lines 14 are formed on the connector 9 side across the drive control circuit 4, and on the opposite side, the NAND memories 10 are arranged in a row along the longitudinal direction of the substrate 8.

[0019] Fig. 5 is a diagram showing the circuit configuration on the surface layer (first layer) L1 of the substrate 8. Fig. 6 is a diagram showing the circuit configuration on the back surface layer (eighth layer) L8 of the substrate 8. In region S of the surface layer L1 of the substrate 8, SATA signal lines 14 are formed from the position where the drive control circuit 4 is disposed to the vicinity of the connector 9. The SATA signal lines 14 then pass through via holes 15 to the back surface layer L8 of the substrate 8 near the connector 9, and reach the connector 9 via the SATA signal lines 14 formed on the back surface layer L8. If it is necessary to form electrodes on the back surface layer L8 side of the substrate 8 in the connector 9 area, it is necessary to pass the SATA signal lines 14 through to the back surface layer L8 of the substrate 8 in this way.

[0020] Most of the area of ​​the back surface layer L8 of the substrate 8, except for the SATA signal lines 14, is ground 18. Although not shown, in the inner layer between the front surface layer L1 and the back surface layer L8 of the substrate 8, almost no wiring patterns other than the SATA signal lines 14 are formed in the areas that overlap with the SATA signal lines 14. In other words, almost no wiring patterns other than the SATA signal lines 14 are formed in the areas of the substrate 8 that overlap with the area S.

[0021] Although the SATA signal lines 14 are partially interrupted on the surface layer L1, this does not pose a problem because the signals passing through the SATA signal lines 14 are relayed by relay elements 16 (see also FIG. 3) mounted on the corresponding portions of the substrate 8. The surface of the substrate 8 is covered with an insulating protective film (not shown), ensuring the insulation of the wiring patterns formed on the surface layer L1.

[0022] 7 is a diagram showing the configuration of wiring connecting the drive control circuit 4 and the NAND memory 10, and is a conceptual diagram of the layer structure of the substrate 8. Note that in FIG. 7, part of the layer structure of the substrate 8 is omitted for simplification of the drawing.

[0023] 7, the wiring connecting the drive control circuit 4 and the resistance element 12 is connected to the drive control circuit 4 on the surface layer L1 of the substrate 8 and is drawn into the inner layer of the substrate 8 by a via hole 21. The wiring is then routed through the inner layer of the substrate 8 and is again drawn out to the surface layer L1 of the substrate 8 by a via hole 22, and is connected to the resistance element 12.

[0024] Moreover, the wiring connecting the resistive element 12 and the NAND memory 10 is connected to the resistive element 12 on the surface layer L1 of the substrate 8 and is drawn into the inner layer of the substrate 8 by the via hole 23. Then, the wiring is routed through the inner layer of the substrate 8 and is again drawn out to the surface layer L1 of the substrate 8 by the via hole 24, and is connected to the NAND memory 10.

[0025] As described above, since the resistive element 12 is disposed near the NAND memory 10, the wiring connecting the resistive element 12 and the NAND memory 10 is shorter than the wiring connecting the drive control circuit 4 and the resistive element 12.

[0026] Here, since the semiconductor device 100 is provided with a plurality of NAND memories 10, a plurality of wirings connecting the resistance elements 12 and the NAND memories 10 are also formed on the substrate 8. Since the resistance elements 12 are disposed in the vicinity of the NAND memories 10, variations in the lengths of the plurality of wirings connecting the resistance elements 12 and the NAND memories 10 are suppressed.

[0027] As described above, by arranging the power supply circuit 5, drive control circuit 4, DRAM 20, NAND memory 10, and SATA signal line 14, each of these elements can be appropriately arranged on the substrate 8, which has an approximately rectangular shape in a plan view.

[0028] Furthermore, by placing the power supply circuit 5 near the connector 9 and away from the SATA signal line 14, noise generated by the power supply circuit 5 is less likely to be picked up by other elements or the SATA signal line 14, thereby improving the operational stability of the semiconductor device 100.

[0029] Furthermore, by arranging the DRAM 20 at a position that avoids the SATA signal line 14, the SATA signal line 14 is less likely to pick up noise generated from the DRAM 20, and the operational stability of the semiconductor device 100 can be improved.

[0030] In general, it is preferable to place the DRAM 20 near the drive control circuit 4. In the first embodiment, the DRAM 20 is placed near the drive control circuit 4, so that degradation of the performance characteristics of the semiconductor device 100 can be suppressed.

[0031] Furthermore, of the four NAND memories 10, two NAND memories 10 are arranged close to one long side of the substrate 8, and the remaining two NAND memories 10 are arranged close to the other long side of the substrate 8. By configuring in this way, it is possible to prevent the wiring pattern from being biased to one side of the substrate 8, and it is possible to form a wiring pattern in a balanced manner.

[0032] Furthermore, since the resistive element 12 is disposed near the NAND memory 10, variations in the lengths of the wiring connecting the resistive element 12 and the NAND memory 10 are reduced, and deterioration of the performance characteristics of the semiconductor device 100 can be suppressed.

[0033] Furthermore, on the back surface layer L8 of the substrate 8, most of the area except for the SATA signal line 14 is ground 18, so that, for example, when the semiconductor device 100 is attached to the host 1 and a device on the host 1 side is present on the back surface layer side of the semiconductor device 100, it is possible to prevent the influence of noise from that device from reaching the wiring pattern of the semiconductor device 100 and each element such as the NAND memory 10. Similarly, the influence of noise from the wiring pattern and each element of the semiconductor device 100 is less likely to be picked up by the device on the host 1 side.

[0034] Furthermore, in the case where it is necessary to form electrodes on the back surface layer side of the substrate 8 in the connector 9 portion as in this embodiment, the SATA signal lines 14 formed on the back surface layer L8 can be made shorter by passing the SATA signal lines 14 through to the back surface layer L8 of the substrate 8 near the connector 9. As a result, if a device on the host 1 side is present on the back surface layer side of the semiconductor device 100, the SATA signal lines 14 are less likely to pick up noise from that device.

[0035] Furthermore, since almost no wiring patterns other than the SATA signal lines 14 are formed in the portion of the substrate 8 that overlaps with the region S, it is possible to easily manage the impedance for the SATA signal lines 14.

[0036] In this embodiment, the substrate 8 has been exemplified as having an eight-layer structure, but the present invention is not limited to this, and the substrate 8 may have a different number of layers.

[0037] Fig. 8 is a bottom view showing a schematic configuration of the semiconductor device 100 according to Modification 1 of the first embodiment. Fig. 9 is a diagram showing the configuration of wiring connecting the drive control circuit 4 and the NAND memory 10, and is a conceptual diagram of the layer configuration of the substrate 8. Note that in Fig. 9, part of the layer structure of the substrate 8 is omitted for simplification of the drawing.

[0038] In this first modification, a NAND memory 10 is also mounted on the back surface side of the substrate 8, and the semiconductor device 100 includes eight NAND memories 10. The NAND memories 10 mounted on the back surface side of the substrate 8 are disposed symmetrically to the NAND memories 10 mounted on the front surface side of the substrate 8.

[0039] The resistive element 12 is not mounted on the back layer side of the substrate 8, but is mounted only on the front layer side. Therefore, the wiring connecting the resistive element 12 and the NAND memory 10 is routed through the inner layer of the substrate 8, branched by via holes 24, and drawn out not only to the front layer L1 but also to the back layer L8 of the substrate 8. The NAND memory 10 provided on the front layer side is connected to the wiring drawn out to the front layer L1, and the NAND memory 10 provided on the back layer side is connected to the wiring drawn out to the back layer L8. In other words, two NAND memories 10 are connected to one resistive element 12.

[0040] In this way, by mounting the NAND memories 10 on both sides of the substrate 8, it is possible to increase the storage capacity of the semiconductor device 100. Furthermore, by branching the wiring midway, it is possible to connect multiple (two in this modification) NAND memories 10 to the resistance element 12, and it is possible to provide the semiconductor device 100 with more NAND memories 10 than the number of channels that the drive control circuit 4 has. In this modification, the drive control circuit 4 has four channels, and it is possible to provide eight NAND memories 10 for that. Note that which of the two NAND memories 10 connected to one wiring is operating is determined by the NAND memory 10 itself depending on whether the CE (chip enable) of the NAND memory 10 is active or not.

[0041] (Second embodiment) Fig. 10 is a plan view showing a detailed configuration of a semiconductor device according to a second embodiment. Fig. 11 is a cross-sectional view taken along line AA shown in Fig. 10. Note that the same components as those in the above-described embodiments are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0042] In the second embodiment, all of the four NAND memories 10 included in the semiconductor device 102 are arranged in parallel along one long side of the substrate 8, more specifically, along the long side where the power supply circuit 5 is provided. By moving all of the NAND memories 10 toward one long side, the resistive elements 12 are arranged together in the space left on the other long side.

[0043] In general, the NAND memory 10 is often configured to be higher than other elements mounted on the substrate 8. Therefore, in the portion of the region T along the other long side of the substrate 8 where the resistance elements 12 are collectively arranged, the height of the semiconductor device 102 can be made lower than the region U where the NAND memory 10 is arranged, as shown in FIG.

[0044] Therefore, if a certain region of the semiconductor device 102 must be lower than other regions due to requirements such as standards, it may be possible to obtain a semiconductor device 102 that satisfies the requirement by arranging the NAND memory 10 so as to avoid that region. In this embodiment, an example is given of a case where the region along the other long side of the substrate 8 must be lower than other regions. The DRAM 20 and the temperature sensor 7 are also provided in region T. However, because the DRAM 20 and the temperature sensor 7 are often configured lower than the NAND memory 10, the height of the semiconductor device 102 in the entire region T can be kept lower than the region U.

[0045] Fig. 12 is a bottom view showing a schematic configuration of a semiconductor device 102 according to Modification 1 of the second embodiment. Fig. 13 is a cross-sectional view taken along line BB shown in Fig. 12. In this Modification 1, similar to Modification 1 of the first embodiment, a NAND memory 10 is also provided on the back surface layer side of the substrate 8 at a position symmetrical to the NAND memory 10 arranged on the front surface layer side. This makes it possible to further increase the storage capacity of the semiconductor device 102.

[0046] Furthermore, by providing the NAND memory 10 at a position symmetrical to the NAND memory 10 arranged on the surface layer side of the substrate 8, the NAND memory 10 is also arranged close to one of the long sides on the back layer side of the substrate 8, so that the height of the semiconductor device 102 in the region T can be kept low.

[0047] In addition, the configuration and effects of providing the resistive element 12 only on the surface layer side of the substrate 8 and connecting two NAND memories 10 to one resistive element 12 are the same as those described in variant example 1 of the first embodiment.

[0048] (Third embodiment) 14 is a plan view showing a schematic configuration of a semiconductor device according to a third embodiment. The same components as those in the above embodiments are denoted by the same reference numerals, and detailed description thereof will be omitted. In this embodiment, two NAND memories 10 are arranged on the connector 9 side of the drive control circuit 4, and two more NAND memories 10 are arranged on the opposite side. That is, a plurality of NAND memories 10 are arranged along the longitudinal direction of the substrate 8, sandwiching the drive control circuit 4 therebetween.

[0049] By distributing the NAND memories 10 in this manner, it is possible to reduce variations in the wiring lengths of the wiring connecting the NAND memories 10 to the drive control circuit 4 compared to disposing four NAND memories 10 in parallel on one side of the drive control circuit 4. For example, in this embodiment, the ratio of the shortest wiring to the longest wiring among the wiring connecting the NAND memories 10 to the drive control circuit 4 can be reduced to about two times. On the other hand, if the same four NAND memories 10 are disposed in parallel on one side of the drive control circuit 4, the ratio of the shortest wiring to the longest wiring will be about four times.

[0050] In this way, in this embodiment, by suppressing variations in wiring length, it is possible to reduce differences in optimal driver settings for the NAND memory 10. As a result, it is possible to suppress the occurrence of data errors and stabilize the operation of the semiconductor device 103.

[0051] The NAND memory 10, which is provided on the connector 9 side of the drive control circuit 4, is provided above the SATA signal line 14. In this embodiment, a BGA (Ball Grid Array) type NAND memory 10 is used, so when forming the SATA signal line 14 on the surface layer L1, it is necessary to avoid the ball-shaped electrodes (bumps) formed on the NAND memory 10.

[0052] 15, many ball-shaped electrodes 25 are provided on the bottom surface of the NAND memory 10, making it difficult to form the SATA signal lines 14 while avoiding the ball-shaped electrodes 25. Therefore, in this embodiment, the SATA signal lines 14 connecting the connector 9 and the drive control circuit 4 are formed on an inner layer of the substrate 8.

[0053] Furthermore, since the NAND memory 10 is disposed close to one long side of the substrate 8, the height of the semiconductor device 103 can be kept low in the area along the other long side. Furthermore, by disposing the resistive element 12 near the NAND memory 10, it is possible to prevent deterioration in the performance characteristics of the semiconductor device 103. The number of NAND memories 10 provided in the semiconductor device 103 is not limited to four, and may be any number greater than four.

[0054] 16 is a bottom view showing a schematic configuration of a semiconductor device according to Modification 1 of the third embodiment. In this Modification 1, similar to Modification 1 of the first embodiment, a NAND memory 10 is also provided on the back surface side of the substrate 8 at a position symmetrical to the NAND memory 10 arranged on the front surface side. This makes it possible to further increase the storage capacity of the semiconductor device 103.

[0055] Furthermore, by providing the NAND memory 10 at a position symmetrical to the NAND memory 10 arranged on the surface layer side of the substrate 8, the NAND memory 10 is also arranged close to one of the long sides on the back layer side of the substrate 8, so that the height of the semiconductor device 103 can be kept low in the area along the other long side.

[0056] In addition, the configuration and effects of providing the resistive element 12 only on the surface layer side of the substrate 8 and connecting two NAND memories 10 to one resistive element 12 are the same as those described in variant example 1 of the first embodiment.

[0057] (Fourth embodiment) 17 is a plan view showing a schematic configuration of a semiconductor device according to a fourth embodiment. Note that the same components as those in the above embodiments are denoted by the same reference numerals, and detailed description thereof will be omitted. In this embodiment, one NAND memory 10 is arranged on the connector 9 side of the drive control circuit 4, and another NAND memory 10 is arranged on the opposite side. In other words, the semiconductor device 104 includes two NAND memories 10.

[0058] When two NAND memories 10 are arranged on either side of the drive control circuit 4 as in this embodiment, the lengths of the multiple wires connecting the drive control circuit 4 and the NAND memory 10 can be made approximately equal. On the other hand, when two NAND memories 10 are similarly arranged in parallel on one side of the drive control circuit 4, the ratio between the shortest wire and the longest wire becomes approximately twice.

[0059] In this way, in this embodiment, by making the wiring lengths of the multiple wirings approximately equal, it is possible to make the optimum driver settings for the NAND memory 10 approximately equal. As a result, it is possible to suppress the occurrence of data errors and stabilize the operation of the semiconductor device 104.

[0060] As in the third embodiment, the SATA signal line 14 is formed in an inner layer of the substrate 8. Furthermore, since the NAND memory 10 is disposed close to one long side of the substrate 8, the height of the semiconductor device 104 can be kept low in the area along the other long side. Furthermore, by disposing the resistive element 12 near the NAND memory 10, deterioration of the performance characteristics of the semiconductor device 104 can be suppressed.

[0061] 18 is a bottom view showing a schematic configuration of a semiconductor device according to Modification 1 of the fourth embodiment. In this Modification 1, similar to Modification 1 of the first embodiment, a NAND memory 10 is also provided on the back surface side of the substrate 8 at a position symmetrical to the NAND memory 10 arranged on the front surface side. This makes it possible to further increase the storage capacity of the semiconductor device 104.

[0062] Furthermore, by providing the NAND memory 10 at a position symmetrical to the NAND memory 10 arranged on the surface layer side of the substrate 8, the NAND memory 10 is also arranged close to one of the long sides on the back layer side of the substrate 8, so that the height of the semiconductor device 104 can be kept low in the area along the other long side.

[0063] In addition, the configuration and effects of providing the resistive element 12 only on the surface layer side of the substrate 8 and connecting two NAND memories 10 to one resistive element 12 are the same as those described in variant example 1 of the first embodiment. [Explanation of symbols]

[0064] 1 host, 2 SATA interface (ATA / IF), 3 communication interface, 4 drive control circuit (controller), 5 power supply circuit, 7 temperature sensor, 8 substrate, 9 connector, 9a slit, 10 NAND memory (NAND type flash memory, non-volatile semiconductor memory element), 12 resistor element, 12a resistor film, 12b protective film, 12c electrode, 14 SATA signal line (signal line), 15 via hole, 18 ground, 20 DRAM (volatile semiconductor memory element), 21, 22, 23, 24 via hole, 25 ball-shaped electrode, 100, 102, 103, 104 semiconductor device, 200 debugging equipment, S, T, U area.

Claims

1. a first nonvolatile semiconductor memory; a second nonvolatile semiconductor memory; a circuit element including a first electrode, a second electrode, a film provided between the first electrode and the second electrode, and a film covering the film; a controller that controls the first and second nonvolatile semiconductor memories; a first signal line connecting the controller and the circuit element; a second signal line connecting the circuit element and the first nonvolatile semiconductor memory and including a first via hole; a third signal line branched from the second signal line by the first via hole and connected to the second nonvolatile semiconductor memory; a connector for connecting to an external device; a substrate on which the first and second nonvolatile semiconductor memories, the circuit element, the controller, and the connector are mounted, The substrate is a surface layer having a wiring pattern formed on a surface of the substrate, on which the first nonvolatile semiconductor memory and the circuit element are mounted; a back surface layer having a wiring pattern formed on the back surface of the substrate and on which the second nonvolatile semiconductor memory is mounted; a plurality of internal wiring layers provided between the front surface layer and the back surface layer and including wiring patterns; and the third signal line includes a second via hole; The semiconductor memory device is configured such that a first region in which the first via hole is provided and a second region in which the second via hole is provided do not overlap each other in a plan view.

2. 2. The semiconductor memory device according to claim 1, wherein the second signal line includes a signal line formed in a first wiring layer which is one of the plurality of internal wiring layers, and a signal line formed in a second wiring layer which is one of the plurality of internal wiring layers and is different from the first wiring layer.

3. 3. The semiconductor memory device according to claim 2, wherein the third signal line includes a signal line formed in a third wiring layer that is one of the plurality of internal wiring layers and is different from the first wiring layer and the second wiring layer.

4. 3. The semiconductor memory device according to claim 2, wherein the second signal line includes a portion extending in a direction substantially perpendicular to the surface of the substrate to connect a signal line formed in the first wiring layer and a signal line formed in the second wiring layer.

5. 3. The semiconductor memory device according to claim 1, wherein the substrate further comprises a SATA signal line connecting the controller and the connector.

6. the substrate includes a fourth signal line connecting the controller and the connector; the connector includes electrodes on the back surface of the substrate for connection to the external device; 3. The semiconductor memory device according to claim 1, wherein the fourth signal line has a portion that passes through a back surface layer of the substrate and is connected to an electrode of the connector, and a portion that is formed in one of the plurality of internal wiring layers.

7. the first nonvolatile semiconductor memory has a plurality of ball-shaped electrodes on a bottom surface; the first nonvolatile semiconductor memory is connected to the substrate via a plurality of ball-shaped electrodes of the first nonvolatile semiconductor memory; the second nonvolatile semiconductor memory has a plurality of ball-shaped electrodes on a bottom surface thereof; 2. The semiconductor memory device according to claim 1, wherein said second nonvolatile semiconductor memory is connected to said substrate via said plurality of ball-shaped electrodes of said second nonvolatile semiconductor memory.

8. the substrate has, in a plan view, a first side and a second side perpendicular to the first side; the connector is provided on the first side of the substrate, 2. The semiconductor storage device according to claim 1, wherein the first and second nonvolatile semiconductor memories are provided on an opposite side of the connector from the position of the controller in a plan view.

9. The semiconductor memory device according to claim 1 , further comprising a temperature sensor.

10. 2. The semiconductor memory device according to claim 1, wherein the first signal line includes a first portion formed on the surface layer, a second portion formed on the back surface layer, and a third portion extending in a direction substantially perpendicular to the surface of the substrate to connect the first portion and the second portion.

11. 11. The semiconductor memory device according to claim 10, wherein the third portion includes a third via hole.

12. 2. The semiconductor memory device according to claim 1, wherein the first nonvolatile semiconductor memory and the second nonvolatile semiconductor memory are arranged symmetrically with respect to the substrate.

13. 2. The semiconductor memory device according to claim 1, wherein the number of layers of the substrate is eight.

14. 2. The semiconductor memory device according to claim 1, wherein the first nonvolatile semiconductor memory determines whether or not to operate in response to a signal from the second signal line based on a chip enable of the first nonvolatile semiconductor memory.

15. 2. The semiconductor memory device according to claim 1, wherein the first and second nonvolatile semiconductor memories are configured to be able to operate individually depending on whether a chip enable of each of the first and second nonvolatile semiconductor memories is active or not.

16. 2. The semiconductor memory device according to claim 1, further comprising a power supply circuit mounted on the substrate, the power supply circuit configured to generate an internal voltage based on a power supply supplied from the outside via the connector, and to supply the generated internal voltage to the first and second nonvolatile semiconductor memories.

17. 17. The semiconductor memory device according to claim 16, wherein the connector is connectable to a host and supplies power input from the host to the power supply circuit.

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