Electronic apparatus

According to one embodiment, an electronic apparatus includes a first substrate, a second substrate, an electronic component, a housing, and a protruding portion. The first substrate has a first face and a second face and is provided with an opening. The second substrate has a third face configured to face the second face and a fourth face and is configured to be electrically connected to the first substrate. The electronic component is configured to be mounted on the third face and is configured to be disposed at a position overlapping the opening in a direction in which the third face faces. The housing is configured to accommodate the first and second substrates. The protruding portion is provided in the housing and is configured to pass through the opening and be thermally connected to the electronic component.

FIELD

Embodiments described herein relate generally to an electronic apparatus.

BACKGROUND

Various apparatuses have a substrate on which electronic components are mounted. When the apparatus operates, the electronic components mounted on the substrate generate heat. The electronic components may be cooled by being thermally connected to a heat sink or a housing of the apparatus, for example.

DETAILED DESCRIPTION

In general, according to one embodiment, an electronic apparatus includes a first substrate, a second substrate, an electronic component, a housing, and a protruding portion. The first substrate has a first surface and a second surface positioned on an opposite side of the first surface and is provided with an opening. The second substrate has a third surface facing the second surface and a fourth surface positioned on an opposite side of the third surface and is configured to be electrically connected to the first substrate. The electronic component is mounted on the third surface of the second substrate and is configured to be disposed at a position overlapping the opening in a direction in which the third surface faces. The housing is configured to accommodate the first and second substrates. The protruding portion is provided in the housing and is configured to pass through the opening so as to be thermally connected to the electronic component.

Hereinafter, a first embodiment will be described with reference toFIGS. 1 to 7. In the present specification, basically, the user side is defined as a front side, the side distant from the user is defined as a rear side, the left side as seen from the user is defined as a left side, the right side as seen from the user is defined as a right side, the upper side as seen from the user is defined as an upper side, and the lower side as seen from the user is defined as a lower side. Moreover, constituent elements according to the embodiment and the description of the elements are sometimes expressed in a plurality of expressions. Other expressions which are not described may be used for the constituent elements and the descriptions thereof. Moreover, other expressions may be used for a constituent element which is not expressed in a plurality of expressions and the description thereof.

FIG. 1is a perspective view illustrating a portion of a data center1according to the first embodiment. The data center1may be also referred to as a server system, a storage system, and an apparatus, for example. The data center1includes various apparatuses such as a plurality of server farms2, a router, and a switching hub, and various components such as cables connecting the apparatuses.FIG. 1illustrates one server farm2.

As illustrated in the drawings, in the present specification, X, Y, and Z-axes are defined. The X, Y, and Z-axes are orthogonal to each other. The X-axis extends along a width of the server farm2. The Y-axis extends along a depth of the server farm2. The Z-axis extends along a height of the server farm2.

The server farm2includes a rack3, a plurality of module enclosures4and a plurality of server modules5. The plurality of server modules5are stored in each of the module enclosures4. The module enclosure4storing the plurality of server modules5therein forms a rack mountable server. The server of the data center1is not limited to this but another server such as a blade server may be used.

The rack3has two supports3aextending in a direction along the Z-axis. A plurality of screw holes arranged in the direction along the Z-axis are provided in the support3a. The two supports3aare disposed so as to be separated in a direction along the X-axis. The module enclosure4can be inserted between the supports3a.

The module enclosure4includes an enclosure case11and attachment members12. The module enclosure4may further include a power supply unit stored in the enclosure case11. For example, four module slots13are provided in the enclosure case11.

The attachment members12extend toward the outer side of the enclosure case11from a front end of the enclosure case11in the direction along the X-axis. Holes corresponding to the screw holes of the support3aare provided in the attachment members12. The attachment members12are fixed to the supports3aof the rack3by bolts, for example. As a result, the module enclosure4is attached to the rack3.

The server module5can be inserted into the module slot13of the enclosure case11. The server module5inserted into the module slot13can be supplied power from, for example, the power supply unit of the module enclosure4. Power may be supplied to the server module5from another apparatus.

The server module5includes a module case21, a module substrate22, a central processing unit (CPU)23, a plurality of memories24, a plurality of fans25, and a plurality of solid-state drives (SSDs)26, for example. The module case21may be also referred to as a housing and a wall, for example. The module substrate22may be also referred to as a substrate, a wiring board, and a circuit board, for example. The fan25may be also referred to as a blowing part and a cooling apparatus, for example. The SSD26is an example of an electronic apparatus and may be also referred to as a storage apparatus, a storage, an electronic apparatus, an apparatus, and a component, for example. The electronic apparatus is not limited to the SSD26and may be another apparatus such as a hybrid hard disk drive (hybrid HDD), for example.

The module case21is formed in an substantially rectangular box shape of which the upper side is open and which extends in a direction along the Y-axis, for example. The shape of the module case21is not limited to this, but may be formed in a box shape having a closed upper side, for example. The module case21accommodates the module substrate22, the CPU23, the memories24, the fans25, the SSDs26, and other components.

The module case21has a front panel27. The front panel27is a wall provided in a front end of the module case21. Various connectors such as a USB connector are provided in the front panel27.

The module substrate22is a printed wiring board, for example. The module substrate22may be another substrate. The CPU23, the memories24, the fans25, the SSDs26, and the other components are mounted on the module substrate22directly or with another component interposed.

The fan25is disposed between the SSDs26and the CPU23and memories24in the direction along the Y-axis. When the fan25operates, the fan can create a flow of air in the direction along the Y-axis inside the module case21. As a result, the fan25can cool the CPU23, the memories24, the SSDs26, and the other components. The flow of air created by the fan25may be created in another direction.

The SSDs26are accommodated in drive cages attached to the front panel27, for example. Without limiting to the SSDs26, other storage apparatuses such as hard disk drives (HDDs) used together with the SSDs26may be accommodated in the drive cages.

FIG. 2is an exploded perspective view of the SSD26of the first embodiment.FIG. 3is a partially cut-away plan view of the SSD26of the first embodiment. As illustrated inFIG. 2, the SSD26includes a case41, a circuit board42, a plurality of flash memories43, a controller44, a plurality of dynamic random-access memories (DRAMs)45, a plurality of capacitors46, and an external connector47.

The case41is an example of a housing and may be also referred to as a cover, a covering portion, and a wall, for example. The circuit board42may be also referred to as a substrate and a wiring board, for example. The flash memory43is an example of a first electronic component and may be also referred to as a storing part, an element, and a component, for example. The controller44is an example of a second electronic component and may be also referred to as a controlling part, as element, and a component, for example. The external connector47may be also referred to as a connecting portion, for example.

FIG. 4is a cross-sectional view of the SSD26of the first embodiment, taken along line F4-F4inFIG. 2.FIG. 5is a cross-sectional view of the SSD26of the first embodiment, taken along line F5-F5inFIG. 2. As illustrated inFIGS. 4 and 5, the case41includes a frame51, a top cover52, and a bottom cover53. The top cover52is an example of a first cover and may be also referred to as a cooling portion, a heat radiating portion, a covering portion, a wall, and a member, for example. The frame51may be also referred to as a wall and a member, for example. The bottom cover53is an example of a second cover and may be also referred to as a cooling portion, a heat radiating portion, a covering portion, a wall, and a member, for example.

As illustrated inFIG. 2, the frame51is formed in an substantially rectangular frame shape and made of metal such as an aluminum alloy, for example. The frame51is not limited to this but may be formed in another shape. The frame51includes a first side wall61, a second side wall62, and two third side walls63.

The first and second side walls61and62extend in the direction along the X-axis. The first and second side walls61and62are disposed at positions separated in the direction along the Y-axis. The first side wall61has an upper face61a, a lower face61b, and a frond end face61c.

The upper face61ais an substantially flat face that faces upward. A concave portion61dis provided substantially in the central portion of the upper face61ain the direction along the X-axis. The concave portion61dforms a surface that is depressed from the upper face61aand is substantially parallel to the upper face61a. The lower face61bis positioned on the opposite side of the upper face61a. The frond end face61cis formed so as to extend from an edge of the upper face61ato an edge of the lower face61band forms one end portion of the frame51in the direction along the Y-axis. A depression portion61eis provided in the first side wall61. The depression portion61eis a cut-off that is open to the lower face61band the frond end face61cof the first side wall61.

The third side walls63are provided between the ends of the first side wall61and the ends of the second side wall62so as to extend in the direction along the Y-axis. The two third side walls63are disposed at positions separated in the direction along the X-axis. An substantially flat first supporting face63athat faces upward is provided in the third side walls63.

An accommodating portion64is provided on the inner side of the first to third side walls61,62, and63of the frame51. The accommodating portion64is a portion surrounded by the first to third side walls61,62, and63. The circuit board42, the flash memories43, the controller44, the DRAMs45, and the capacitors46are accommodated in the accommodating portion64.

The top cover52is attached to the frame51from above by screws, for example. As a result, the top cover52closes the accommodating portion64of the frame51from above. Further, the bottom cover53is attached to the frame51from below by screws, for example. As a result, the bottom cover53closes the accommodating portion64of the frame51from below.

As illustrated inFIG. 5, the circuit board42includes a first circuit board71and a second circuit board72. The first circuit board71is an example of a first substrate. The second circuit board72is an example of a second substrate. The first and second circuit boards71and72are printed wiring boards, for example. The first and second circuit boards71and72are not limited to this but may be other types of substrates. Moreover, the SSD26may have only one printed wiring board and may have three or more printed wiring boards.

The first circuit board71has a first surface71a, a second surface71b, and a plurality of first end faces71c. The first surface71ais an example of a first face and may be also referred to as a face facing a cover, for example. The second surface71bis an example of a second face. The first surface71ais a substantially flat face that faces the top cover52. The first surface71ais covered by the top cover52. The plurality of flash memories43are mounted on the first surface71a.

The flash memory43is a NAND-type flash memory, for example. The first electronic component is not limited to this but may be another component such as a resistance random access memory (ReRAM) or a ferroelectric random access memory (FeRAM). The flash memory43can store information.

The second surface71bis an substantially flat face that is positioned on the opposite side of the first surface71aand faces the bottom cover53. A portion of an end portion of the second surface71bfaces the first supporting face63aof the third side wall63of the frame51. The first circuit board71is attached, for example, by screws, to a portion of the first supporting face63aof the third side wall63, facing the end portion of the second surface71b.

As illustrated inFIG. 4, a plurality of pads75are provided on the second surface71b. The pads75are electrodes provided for electrical connection of the terminals of the flash memory43and may be also referred to as conductive portions and terminals, for example. In other words, the pads75are portions for mounting the flash memory43. The flash memory43may be mounted on the pads75.

The first end face71cis provided so as to extend between an edge of the first surface71aand an edge of the second surface71b. The first end face71cfaces in a direction substantially orthogonal to the direction in which the first surface71afaces (the direction along the Z-axis).

FIG. 6is a schematic cross-sectional view of a portion of the SSD26of the first embodiment. As illustrated inFIG. 6, the first circuit board71includes a first base portion81, a first conductor layer82, a first conductor pattern83, a second conductor pattern84, a first insulating layer85, a second insulating layer86, and a plurality of first vias87. The first conductor layer82may be also referred to as a conductive layer. The first via87may be also referred to as a connecting portion and a via.

The first base portion81is a portion on which a plurality of insulating layers and a plurality of conductor layers are stacked, for example. The conductor layers inside the first base portion81form a wiring, a land, and a pattern such as a solid pattern, for example. The first base portion81has a first formed face81aand a second formed face81b. The second formed face81bis positioned on the opposite side of the first formed face81a.

The first conductor layer82is provided inside the first base portion81. Due to this, the first conductor layer82is positioned between the first surface71aand the second surface71b. The first conductor layer82is a so-called solid pattern and is used as the ground of the first circuit board71. The first conductor layer82is not limited to the ground but may be used as a power layer, for example.

The first conductor pattern83is provided on the first formed face81aof the first base portion81. The first conductor pattern83forms patterns such as wirings and lands, for example. The first insulating layer85covers the first conductor pattern83. The first insulating layer85forms at least a portion of the first surface71aof the first circuit board71.

A first exposing opening85ais provided in the first insulating layer85. The first exposing opening85aexposes at least a portion of the first conductor pattern83. The first conductor pattern83exposed by the first exposing opening85aforms a pattern provided on the first surface71aof the first circuit board71. A portion of the first conductor pattern83exposed by the first exposing opening85afaces the top cover52.

At least one of the first conductor patterns83exposed by the first exposing opening85ais provided in an end portion of the first surface71aof the first circuit board71. The end portion of the first surface71ais a portion that extends along the first end face71cof the first circuit board71. For example, the end portion of the first surface71ais a portion disposed between the first end face71cand various electronic components such as the flash memories43mounted on the first surface71a. The first conductor pattern83exposed by the first exposing opening85amay be provided at another position.

The SSD26further includes a plurality of first heat conduction sheets88. The first heat conduction sheet88may be also referred to as a heat transfer member, for example. The first heat conduction sheet88is interposed between the top cover52and the portion of the first conductor pattern83exposed by the first exposing opening85a. Due to this, the first circuit board71supports the top cover52with the first heat conduction sheet88interposed.

The number of first heat conduction sheets88may be larger or smaller than the number of portions of the first conductor patterns83exposed by the first exposing opening85a. For example, one first heat conduction sheet88may be provided over a plurality of first conductor patterns83, and a plurality of first heat conduction sheets88may be attached to one first conductor pattern83.

The first heat conduction sheet88thermally connects the top cover52and the first conductor pattern83exposed by the first exposing opening85a. The first heat conduction sheet88has higher elasticity than the first circuit board71and has higher elasticity than the top cover52. The first heat conduction sheet88is elastically compressed between the first circuit board71and the top cover52and is stuck to the first circuit board71and the top cover52.

The second conductor pattern84is provided in the second formed face81bof the first base portion81. The second conductor pattern84forms patterns such as wirings and lands, for example. The second insulating layer86covers the second conductor pattern84. The second insulating layer86forms at least a portion of the second surface71bof the first circuit board71.

A second exposing opening86ais provided in the second insulating layer86. The second exposing opening86aexposes at least a portion of the second conductor pattern84. The second conductor pattern84exposed by the second exposing opening86aforms a pattern provided on the second surface71bof the first circuit board71. The portion of the second conductor pattern84exposed by the second exposing opening86afaces the first supporting face63aof the third side wall63of the frame51.

At least one of the second conductor patterns84exposed by the second exposing opening86ais formed in an end portion of the second surface71bof the first circuit board71. The end portion of the second surface71bis a portion that extends along the first end face71cof the first circuit board71. For example, the end portion of the second surface71bis a portion disposed between the first end face71cand various electronic components mounted on the second surface71b. The second conductor pattern84exposed by the second exposing opening86amay be provided at another position.

The SSD26further includes a plurality of second heat conduction sheets89. The second heat conduction sheet89may be also referred to as a heat transfer member, for example. The second heat conduction sheet89is interposed between the first supporting face63aof the third side wall63and the portion of the second conductor pattern84exposed by the second exposing opening86a. Due to this, the first circuit board71is supported by the first supporting face63aof the third side wall63with the second heat conduction sheet89interposed.

The first supporting face63aof the third side wall63of the frame51supports both end portions and substantially the central portion of the first circuit board71in the direction in which the first circuit board71extends (the direction along the Y-axis), for example. The frame51may support the other portions of the first circuit board71.

The number of second heat conduction sheets89may be larger or smaller than the number of portions of the second conductor patterns84exposed by the second exposing opening86a. For example, one second heat conduction sheet89may be provided over a plurality of second conductor patterns84, and a plurality of second heat conduction sheets89may be attached to one second conductor pattern84.

The second heat conduction sheet89thermally connects the frame51and the second conductor pattern84exposed by the second exposing opening86a. The second heat conduction sheet89has higher elasticity than the first circuit board71and has higher elasticity than the frame51. The second heat conduction sheet89is elastically compressed between the first circuit board71and the frame51and is stuck to the first circuit board71and the frame51.

The plurality of first vias87are provided in the first base portion81. The plurality of first vias87connect the first conductor layer82, the first conductor pattern83, and the second conductor pattern84electrically and thermally.

The flash memories43mounted on the first circuit board71overlap the first conductor layer82in the thickness direction of the first circuit board71(the direction along the Z-axis). The flash memory43may be disposed at another position.

The second circuit board72overlaps the first circuit board71in the direction along the Z-axis with a gap interposed. The direction along the Z-axis may be also referred to as a thickness direction of a first substrate, for example. The second circuit board72has a third surface72a, a fourth surface72b, and a second end face72c. The third surface72ais an example of a third face and may be also referred to as a face facing a cover, for example. The fourth surface72bis an example of a fourth face.

The third surface72ais an substantially flat face that faces the top cover52. Further, the third surface72afaces the second surface71bof the first circuit board71. The plurality of flash memories43and the controller44, and the plurality of DRAMs45are mounted on the third surface72a.

A second supporting face63bis provided on the third side wall63of the frame51. The second supporting face63bis a substantially flat face that is positioned on the opposite side of the first supporting face63aand faces downward. A portion of an end portion of the third surface72aof the second circuit board72faces the second supporting face63bof the third side wall63of the frame51.

The second circuit board72is attached, for example, by screws, to a portion of the second supporting face63bof the third side wall63of the frame51, facing the end portion of the third surface72a. The second circuit board72is attached to the frame51at a position separated from the first circuit board71in the direction in which the third face72afaces (the direction along the Z-axis). That is, the frame51is interposed between the first circuit board71and the second circuit board72.

The controller44is a system-on-a-chip (SoC), for example. The second electronic component is not limited to this. When the SSD26operates, the controller44generates a larger amount of heat than the flash memory43. The controller44can control the plurality of flash memories43.

The controller44is thicker than the flash memory43. In other words, the length of the controller44is larger than the flash memory43in the direction in which the third surface72aof the second circuit board72faces (the direction along the Z-axis). The dimensions of the flash memory43and the controller44are not limited thereto.

The fourth surface72bis an substantially flat face that is positioned on the opposite side of the third surface72aand faces the bottom cover53. The fourth surface72bis covered by the bottom cover53. The plurality of flash memories43are mounted on the fourth surface72b.

The second end face72cis formed so as to extend between an edge of the third surface72aand an edge of the fourth surface72b. The second end face72cfaces in a direction substantially orthogonal to the direction in which the third surface72afaces (the direction along the Z-axis).

As illustrated inFIG. 4, the external connector47is mounted on the second circuit board72. As illustrated inFIG. 4, for example, the external connector47is disposed in a cut-off72dthat is provided in one end portion of the second circuit board72in the direction along the Y-axis. The cut-off72dis open to the second end face72cof the second circuit board72. The end portion of the second circuit board72in which the external connector47is provided is located closer to the first side wall61than the second and third side walls62and63of the frame51. The external connector47is fitted in the depression portion61eprovided in the first side wall61of the frame51.

As illustrated inFIG. 2, the external connector47has two supporting pieces47a. The supporting piece47aextends in the direction along the X-axis and overlaps the second circuit board72in the direction along the Z-axis. The supporting piece47ais supported on the third surface72aof the second circuit board72.

The external connector47is exposed outside the SSD26. The external connector47is electrically connected to the module substrate22by a connector connected to the module substrate22of the server module5, for example. As a result, the SSD26can be supplied with power from the server module5or the module enclosure4and transmit data.

As illustrated inFIG. 6, the second circuit board72includes a second base portion91, a second conductor layer92, a third conductor pattern93, a fourth conductor pattern94, a third insulating layer95, a fourth insulating layer96, and a plurality of second vias97. The second conductor layer92may be also referred to as a conductive layer, for example. The second via97may be also referred to as a connecting portion, for example.

The second base portion91is a portion on which a plurality of insulating layers and a plurality of conductor layers are stacked, for example. The conductor layers inside the second base portion91form a wiring, a land, and a pattern such as a so-called solid pattern, for example. The second base portion91has a third formed face91aand a fourth formed face91b. The fourth formed face91bis positioned on the opposite side of the third formed face91a.

The second conductor layer92is provided inside the second base portion91. Due to this, the second conductor layer92is positioned between the third surface72aand the fourth surface72b. The second conductor layer92is a so-called solid pattern and is used as the ground of the second circuit board72. The second conductor layer92is not limited to the ground but may be used as a power layer, for example.

The third conductor pattern93is formed on the third formed face91aof the second base portion91. The third conductor pattern93forms patterns such as wirings and lands, for example. The third insulating layer95covers the third conductor pattern93. The third insulating layer95forms at least a portion of the third surface72aof the second circuit board72.

A third exposing opening95ais provided in the third insulating layer95. The third exposing opening95aexposes at least a portion of the third conductor pattern93. The third conductor pattern93exposed by the third exposing opening95aforms a pattern formed on the third surface72aof the second circuit board72. A portion of the third conductor pattern93exposed by the third exposing opening95afaces the second supporting face63bof the third side wall63of the frame51.

At least one of the third conductor patterns93exposed by the third exposing opening95ais provided in an end portion of the third surface72aof the second circuit board72. The end portion of the third surface72ais a portion that extends along the second end face72cof the second circuit board72. For example, the end portion of the third surface72ais a portion disposed between the second end face72cand various electronic components such as the flash memories43mounted on the third surface72a. The third conductor pattern93exposed by the third exposing opening95amay be provided at another position.

The SSD26further includes a plurality of third heat conduction sheets98. The third heat conduction sheet98may be also referred to as a heat transfer member, for example. The third heat conduction sheet98is interposed between the second supporting face63bof the third side wall63and the portion of the third conductor pattern93exposed by the third exposing opening95a. Due to this, the second circuit board72is supported on the second supporting face63bof the third side wall63with the third heat conduction sheet98interposed.

The second supporting face63bof the third side wall63of the frame51supports both end portions and substantially the central portion of the second circuit board72in the direction in which the second circuit board72extends (the direction along the Y-axis), for example. The frame51may support the other portions of the second circuit board72.

The number of third heat conduction sheets98may be larger or smaller than the number of portions of the third conductor patterns93exposed by the third exposing opening95a. For example, one third heat conduction sheet98may be provided over a plurality of third conductor patterns93, and a plurality of third heat conduction sheets98may be attached to one third conductor pattern93.

The third heat conduction sheet98thermally connects the frame51and the third conductor pattern93exposed by the third exposing opening95a. The third heat conduction sheet98has higher elasticity than the second circuit board72and has higher elasticity than the frame51. The third heat conduction sheet98is elastically compressed between the second circuit board72and the frame51and is stuck to the second circuit board72and the frame51.

The fourth conductor pattern94is provided on the fourth formed face91bof the second base portion91. The fourth conductor pattern94forms patterns such as wirings and lands, for example. The fourth insulating layer96covers the fourth conductor pattern94. The fourth insulating layer96forms at least a portion of the fourth surface72bof the second circuit board72.

A plurality of second vias97are provided in the second base portion91. The plurality of second vias97connect the second conductor layer92, the third conductor pattern93, and the fourth conductor pattern94electrically and thermally.

The flash memories43and the controller44mounted on the second circuit board72overlap the second conductor layer92in the thickness direction of the second circuit board72(the direction along the Z-axis). The flash memories43and the controller44may be disposed at another position.

As illustrated inFIG. 4, the first circuit board71further includes a first substrate connector101. The first substrate connector101is an example of a first connector and may be also referred to as a protruding portion and a connecting portion, for example. The first substrate connector101is mounted on the second surface71band protrudes toward the third surface72aof the second circuit board72from the second surface71b.

The second circuit board72further includes a second substrate connector102. The second substrate connector102is an example of a second connector and may be also referred to as a protruding portion and a connecting portion, for example. The second substrate connector102is mounted on the third surface72aand protrudes toward the second surface71bof the first circuit board71from the third surface72a.

The first substrate connector101is connected to the second substrate connector102. Due to this, the first and second circuit boards71and72are connected electrically each other, and the flash memories43mounted on the first circuit board71and the controller44mounted on the second circuit board72are connected electrically. Thus, the controller44can control the flash memories43mounted on the first circuit board71as well as the flash memories43mounted on the second circuit board72.

The first substrate connector101is disposed substantially in the central portion of the first circuit board71in the direction in which the first circuit board71extends (the direction along the Y-axis). Further, the second substrate connector102is disposed substantially in the central portion of the second circuit board72in the direction in which the second circuit board72extends (the direction along the Y-axis). Due to this, the first and second substrate connectors101and102support substantially the central portions of the first and second circuit boards71and72, respectively. The first and second substrate connectors101and102may be disposed at another position.

As illustrated inFIG. 3, a plurality of electronic components104and105are further mounted on the first surface71aof the first circuit board71. The plurality of electronic components104and105are various components such as inductors, for example. Some of the plurality of electronic components104are disposed at a position overlapping the first substrate connector101in the thickness direction of the first circuit board71(the direction along the Z-axis). The length (thickness) of the electronic component105in the direction along the Z-axis is larger than the length (thickness) of the electronic component104.

As illustrated inFIG. 4, some of the plurality of flash memories43mounted on the fourth surface72bof the second circuit board72are disposed so as to overlap the second substrate connector102in the thickness direction of the second circuit board72(the direction along the Z-axis). In other words, the flash memories43are mounted on the fourth surface72bat a position overlapping the second substrate connector102in the direction in which the fourth surface72bfaces.

An opening106is provided in the first circuit board71. The opening106may be also referred to as an insertion portion, for example. The opening106is a cut-off that is open to the first end face71cof the first circuit board71, for example. The first end face71cin which the opening106is provided is one end face of the first circuit board71in the direction along the Y-axis and is located closer to the first side wall61than the second and third side walls62and63. The opening106is not limited to this but may be a hole or a slit, for example.

The opening106is provided at a position corresponding to the controller44mounted on the second circuit board72. That is, the opening106is disposed at a position overlapping the controller44in the direction in which the third surface72aof the second circuit board72faces (the direction along the Z-axis). The opening106exposes the controller44to the top cover52. In other words, since the opening106is provided, the first circuit board71is formed in a region outside the region between the controller44and the top cover52.

The opening106is larger than the controller44. In other words, when seen in a plan view from the direction in which the third surface72aof the second circuit board72faces (the direction along the Z-axis), the controller44is surrounded by the edges of the first circuit board71, which form the opening106. The size of the opening106is not limited to this.

The plurality of capacitors46are mounted on the first circuit board71. The capacitor46is disposed between the first end face71cof the first circuit board71and the second side wall62of the frame51. The first end face71cthat faces the capacitor46is the other end face of the first circuit board71in the direction along the Y-axis. The plurality of capacitors46extend in the direction along the Y-axis and is arranged in the direction along the X-axis. In other words, the capacitor46extends in the direction crossing the thickness direction of the first circuit board71.

The capacitor46is disposed at a position located further from the controller44than the flash memories43. Due to this, the capacitor46is suppressed from being heated by the heat generated by the controller44.

As illustrated inFIGS. 3 and 4, the top cover52includes a controller cover111, a memory cover112, and a plurality of screws113. The controller cover111and the memory cover112may be also referred to as a cover, a heat radiating portion, a cooling portion, a covering portion, a portion, and a member, for example.

The controller cover111is made of an aluminum alloy, for example. The material of the controller cover111is not limited to this. The controller cover111is formed by casting, for example, and is coated with insulating black paint on the surface. The controller cover111is formed substantially in a T-shape and includes a first heat radiating portion121and a second heat radiating portion122. The first and second heat radiating portions121and122may be also referred to as an extension portion or a portion, for example.

The first heat radiating portion121is formed in a planar board-like shape extending along the first side wall61of the frame51. The first heat radiating portion121is supported on the upper face61aof the first side wall61. Due to this, the controller cover111is located closer to the external connector47than the memory cover112. Further, the first heat radiating portion121of the controller cover111overlaps the external connector47in the thickness direction of the second circuit board72(the direction along the Z-axis).

The first heat radiating portion121has a convex portion121athat protrudes toward the concave portion61dof the first side wall61. The convex portion121ais disposed at a position corresponding to the concave portion61dand is fitted to the concave portion61d. Due to this, it is easy to align the controller cover111in relation to the frame51.

The second heat radiating portion122is a portion that extends in the direction along the Y-axis from substantially the central portion in the direction along the X-axis of the first heat radiating portion121. The length of the second heat radiating portion122in the direction along the X-axis is smaller than the length of the first heat radiating portion121in the direction along the X-axis. The length of the first and second heat radiating portions121and122is not limited to this.

The second heat radiating portion122covers the controller44on the second circuit board72, which is exposed by the opening106of the first circuit board71. The second heat radiating portion122may cover at least a portion of the controller44. The second heat radiating portion122may further cover other components mounted on the first and second circuit boards71and72.

A protruding portion123is provided in the second heat radiating portion122. The protruding portion123protrudes toward the controller44mounted on the second circuit board72and passes through the opening106. In other words, at least a portion of the protruding portion123is accommodated in the opening106. The protruding portion123is separated from the edges of the first circuit board71that form the opening106.

The protruding portion123has a contacting portion123a. The contacting portion123aprotrudes toward the controller44. A contacting surface123bthat faces the controller44is provided in the contacting portion123a. The contacting surface123bis a portion in which paint is removed and the material of the controller cover111is exposed by cutting, for example.

The SSD26further includes a fourth heat conduction sheet125. The fourth heat conduction sheet125is an example of a first heat transfer member. The fourth heat conduction sheet125is interposed between the controller44and the contacting surface123bof the protruding portion123. Due to this, the controller44supports the controller cover111with the fourth heat conduction sheet125interposed.

The fourth heat conduction sheet125connects the controller44and the protruding portion123of the controller cover111thermally. The fourth heat conduction sheet125has higher elasticity than the controller cover111and has higher elasticity than the controller44. The fourth heat conduction sheet125is elastically compressed between the controller cover111and the controller44and is stuck to the controller cover111and the controller44. Further, the fourth heat conduction sheet125absorbs a variation in the dimension of the gap between the controller44and the contacting surface123bof the protruding portion123.

As illustrated inFIG. 2, the controller cover111further includes an inner face111aand an outer face111b. The inner face111afaces the inner side of the SSD26. For example, a portion of the inner face111aformed in the second heat radiating portion122faces the second circuit board72. The outer face111bis positioned on the opposite side of the inner face111aand faces the outer side of the SSD26.

The controller cover111further includes a plurality of fins127. The fin127may be also referred to as a heat radiating portion, a cooling portion, and a protruding portion, for example. The fin127is provided on the outer face111bof the controller cover111. The fin127is a planar plate-like portion that extends in the direction along the Y-axis. In other words, the fin127extends in the direction of the flow of air created by the fans25of the server module5. The extension direction of the fin127is not limited to this.

As illustrated inFIGS. 4 and 5, the memory cover112includes a covering member131, a protruding member132, and a seal133. The covering member131and the protruding member132are made of an aluminum alloy, for example. The material of the covering member131and the protruding member132is not limited to this.

The covering member131is made of a metal plate which is bent, for example. The covering member131may be formed by another method. The covering member131has a first covering portion131a, a plurality of first edge portions131b, and a plurality of second edge portions131c.

The first covering portion131acovers at least a portion of the first surface71aof the first circuit board71. The first covering portion131amay further cover at least a portion of the second circuit board72exposed by the opening106, for example.

As illustrated inFIG. 3, a plurality of holes131dare provided in the first covering portion131a. The plurality of holes131dis provided at positions corresponding to the plurality of capacitors46. A portion of the capacitor46can be inserted into the hole131d. Due to this, the hole131dsuppresses the capacitor46from interfering with the first covering portion131a.

A plurality of first projected portions131eare provided on the first covering portion131a. The first projected portion131eis formed by raising, for example. The first projected portion131eprotrudes toward the first circuit board71. The plurality of first projected portions131eoverlaps substantially the central portion of the first circuit board71in the direction along the Y-axis and is arranged in the direction along the X-axis. The first projected portion131eis not limited to this.

As illustrated inFIGS. 4 and 5, the first edge portion131bextends toward the second or third side walls62or63from an end portion of the first covering portion131aoverlapping the second or third side wall62or63. The first edge portion131bmakes contact with the corresponding second or third side wall62or63. As a result, the memory cover112is supported by the frame51.

As illustrated inFIG. 6, an extension portion131fis provided in a portion of the first edge portion131b. The extension portion131fextends in the direction along the first surface71aof the first circuit board71from the first edge portion131b. That is, the extension portion131fis connected to the first covering portion131awith the first edge portion131binterposed. The extension portion131foverlaps the first conductor pattern83provided in the end portion of the first circuit board71.

The first heat conduction sheet88is interposed between the extension portion131fof the memory cover112and the portion of the first conductor pattern83exposed by the first exposing opening85a. Due to this, the first heat conduction sheet88connects the first conductor pattern83and the extension portion131fof the memory cover112thermally.

As illustrated inFIG. 4, the second edge portion131cextends toward the second heat radiating portion122from the end portion of the first covering portion131aadjacent to the second heat radiating portion122of the controller cover111. The distal end of the second edge portion131cis separated by a very small distance from the second heat radiating portion122. In other words, a gap G is formed between the controller cover111and a portion of the memory cover112.

The covering member131further has an inner face131gand an outer face131h. The inner face131gfaces the inner side of the SSD26. For example, a portion of the inner face131gfaces the first circuit board71. The outer face131his positioned on the opposite side of the inner face131gand faces the outer side of the SSD26.

The protruding member132is made of a metal plate which is bent, for example. The protruding member132may be formed by another method. The protruding member132is attached to the inner face131gof the covering member131. The protruding member132has a second covering portion132a, a fixing portion132b, and a plurality of second projected portions132c. The second projected portion132cis an example of a second protruding portion and may be also referred to as a convex portion, for example.

The second covering portion132ais disposed between the first covering portion131aand the first circuit board71and covers a portion of the first circuit board71. The second covering portion132acovers at least some of the plurality of flash memories43mounted on the first surface71aof the first circuit board71. In other words, the second covering portion132afaces the plurality of flash memories43mounted on the first surface71aof the first circuit board71. The second covering portion132ais formed separately from the electronic component105mounted on the first surface71a.

The fixing portion132bextends toward the first covering portion131aof the covering member131from the end portion of the second covering portion132a. The fixing portion132bis attached to the first covering portion131aby caulking, for example. Due to this, the second covering portion132ais supported at a position at which a gap is formed between the first covering portion131aand the second covering portion132a, and a gap is formed between the flash memory43and the second covering portion132a.

The fixing portion132bof the protruding member132is attached to the covering member131to form the memory cover112in a substantially box shape that forms a space between the covering member131and the protruding member132. The box-shaped portion of the memory cover112is formed in a substantially U-shape along the second heat radiating portion122of the controller cover111when seen in a plan view from the direction along the Z-axis. That is, the box-shaped portion of the memory cover112has a portion that extends in the direction along the Y-axis and a portion that extends in the direction along the X-axis. Such a memory cover112suppresses deformation of the memory cover112in the Y and X-axis directions.

The second projected portion132cis provided in the second covering portion132aat a position corresponding to the first projected portion131e. In other words, the second projected portion132coverlaps the first projected portion131ein the direction along the Z-axis.

The second projected portion132cis formed by a raising, for example. The second projected portion132cprotrudes toward the first surface71aof the first circuit board71. The first projected portion131eis fitted into the recessed portion of the second projected portion132c. The first projected portion131emakes contact with the second projected portion132cand is connected to the second projected portion132cthermally.

The convex portion of the second projected portion132cmakes contact with some of the electronic components104on the first circuit board71with an insulating heat conduction sheet interposed, for example. Due to this, the second projected portion132cis thermally connected to the first circuit board71with the electronic component104interposed. The second projected portion132cmay make contact with the first circuit board71and the conductor patterns formed in the first circuit board71, for example, without being limited to the electronic components104.

The second projected portion132cmakes contact with the electronic components104disposed substantially in the central portion of the first circuit board71in the direction along the Y-axis. Due to this, the second projected portion132csupports the first circuit board71and suppresses the first circuit board71from bending.

The second projected portion132cmakes contact with the electronic components104at a position overlapping the first and second substrate connectors101and102in the direction along the Z-axis. Due to this, the first circuit board71and the electronic components104are held between the second projected portion132cand the first and second substrate connectors101and102.

The seal133blocks the plurality of holes131dof the covering member131. Thus, the seal133suppresses entering of dust and moisture into the case41through the holes131d. Further, the seal133makes contact with the plurality of capacitors46to support the plurality of capacitors46. The seal133is interposed between the capacitor46and the covering member131and suppresses the capacitor46from making direct contact with the covering member131.

The SSD26further includes a plurality of fifth heat conduction sheets135. The fifth heat conduction sheet135is an example of a third heat transfer member. The fifth heat conduction sheet135is interposed between the second covering portion132aof the protruding member132and the flash memory43mounted on the first surface71aof the first circuit board71. Due to this, the flash memory43supports the memory cover112with the fifth heat conduction sheet135interposed.

The fifth heat conduction sheet135connects the memory cover112and the flash memory43mounted on the first surface71athermally. The fifth heat conduction sheet135has higher elasticity than the memory cover112and has higher elasticity than the flash memory43. The fifth heat conduction sheet135is elastically compressed between the memory cover112and the flash memory43and is stuck to the memory cover112and the flash memory43. Further, the fifth heat conduction sheet135absorbs a variation in the dimension of the gap between the flash memory43and the second covering portion132aof the protruding member132.

As illustrated inFIG. 2, the screws113attach the controller cover111to the memory cover112. The controller cover111makes contact with the memory cover112partially to be attached to the memory cover112. The screws113further attach the controller cover111and the memory cover112attached together to the frame51.

The bottom cover53is made of an aluminum alloy, for example. The bottom cover53is made of a metal plate which is bent, for example. The bottom cover53may be made of another material and may be formed by another method.

As illustrated inFIGS. 4 and 5, the bottom cover53covers the fourth surface72bof the second circuit board72and the plurality of flash memories43mounted on the fourth surface72bof the second circuit board72. The bottom cover53is supported on the first to third side walls61to63of the frame51.

The SSD26further includes a plurality of sixth heat conduction sheets141. The sixth heat conduction sheet141is an example of a second heat transfer member. The sixth heat conduction sheet141is interposed between the bottom cover53and the flash memory43mounted on the fourth surface72b. Due to this, the flash memory43supports the bottom cover53with the sixth heat conduction sheet141interposed.

The sixth heat conduction sheet141connects the bottom cover53and the flash memory43mounted on the fourth surface72bthermally. The sixth heat conduction sheet141has higher elasticity than the flash memory43and has higher elasticity than the bottom cover53. The sixth heat conduction sheet141is elastically compressed between the flash memory43and the bottom cover53and is stuck to the flash memory43and the bottom cover53.

As illustrated inFIG. 2, the bottom cover53has edge pieces145. The edge piece145protrudes toward the second circuit board72from one end portion of the bottom cover53in the direction along the Y-axis. The edge piece145presses the supporting piece47aof the external connector47supported on the second circuit board72against the first side wall61of the frame51. Due to this, the connector47and the second circuit board72are held between the first side wall61and the edge piece145.

When the SSD26described above operates, the flash memories43and the controller44generate heat. The flash memories43and the controller44are cooled in the manner described below, for example. However, cooling of the flash memories43and the controller44is not limited to that described below.

The flash memory43mounted on the first surface71aof the first circuit board71illustrated inFIG. 4is thermally connected to the memory cover112with the fifth heat conduction sheet135interposed. Due to this, the heat generated from the flash memory43is transmitted to the memory cover112via the fifth heat conduction sheet135.

Further, the flash memory43mounted on the first surface71aof the first circuit board71overlaps the first conductor layer82ofFIG. 6in the thickness direction of the first circuit board71(the direction along the Z-axis). Due to this, the heat generated from the flash memory43is transmitted to the first and second conductor patterns83and84from the first conductor layer82via the first via87. The heat transmitted to the first conductor pattern83is transmitted to the memory cover112via the first heat conduction sheet88. The heat transmitted to the second conductor pattern84is transmitted to the frame51via the second heat conduction sheet89.

As described above, the heat generated from the flash memory43mounted on the first surface71aof the first circuit board71is transmitted to the memory cover112and the frame51. As a result, the flash memory43is cooled.

The flash memory43mounted on the fourth surface72bof the second circuit board72illustrated inFIG. 4is thermally connected to the bottom cover53with the sixth heat conduction sheet141interposed. Due to this, the heat generated from the flash memory43is transmitted to the bottom cover53via the sixth heat conduction sheet141.

Further, the flash memory43mounted on the fourth surface72bof the second circuit board72overlaps the second conductor layer92ofFIG. 6in the thickness direction of the second circuit board72(the direction along the Z-axis). Due to this, the heat generated from the flash memory43is transmitted to the third conductor pattern93from the second conductor layer92via the second via97. The heat transmitted to the third conductor pattern93is transmitted to the frame51via the third heat conduction sheet98.

As described above, the heat generated from the flash memory43mounted on the fourth surface72bof the second circuit board72is transmitted to the bottom cover53and the frame51. As a result, the flash memory43is cooled.

The controller44illustrated inFIG. 4is thermally connected to the controller cover111with the fourth heat conduction sheet125interposed. Due to this, the heat generated from the controller44is transmitted to the controller cover111via the fourth heat conduction sheet125.

The controller44overlaps the second conductor layer92ofFIG. 6in the thickness direction of the second circuit board72(the direction along the Z-axis). Due to this, the heat generated from the controller44is transmitted to the third conductor pattern93from the second conductor layer92via the second via97. The heat transmitted to the third conductor pattern93is transmitted to the frame51via the third heat conduction sheet98.

As described above, the heat generated from the controller44is transmitted to the controller cover111and the frame51. The plurality of fins127formed on the controller cover111increases the surface area of the controller cover111. Further, the wind created by the fans25of the server module5flows along the fins127. Thus, the controller cover111is cooled efficiently and the controller44is also cooled.

The controller44generates a larger amount heat than the flash memory43. Thus, the amount of heat transmitted to the controller cover111may be larger than the amount of heat transmitted to the memory cover112. However, since the gap G is formed between the controller cover111and a portion of the memory cover112, the heat transmitted to the controller cover111is suppressed from being transmitted to the memory cover112. Due to this, even when the temperature of the controller cover111is higher than the temperature of the memory cover112, the memory cover112is suppressed from being heated by the controller cover111.

Further, the second projected portion132cof the memory cover112makes contact with the electronic component104at the position overlapping the first and second substrate connectors101and102in the direction along the Z-axis. Due to this, the heat of the second circuit board72is transmitted to the second projected portion132cof the memory cover112via the first and second substrate connectors101and102, the first circuit board71, and the electronic component104. As a result, the second circuit board72is cooled.

In the data center1according to the first embodiment, the flash memory43overlaps the first conductor layer82in the thickness direction of the first circuit board71. The first conductor layer82is thermally connected to the first conductor pattern83by the first via87and the first conductor pattern83is thermally connected to the top cover52by the first heat conduction sheet88. Due to this, the heat generated from the flash memory43is transmitted to the top cover52via the first conductor layer82, the first via87, the first conductor pattern83, and the first heat conduction sheet88. Thus, the heat generated from the flash memory43is radiated by the top cover52and a rise in the temperature inside the case41is suppressed.

The first conductor pattern83is formed in the end portion of the first surface71a. The components and wirings of the first circuit board71may be provided at a position separated from the end portion of the first circuit board71rather than in the end portion of the first circuit board71. Thus, the first conductor pattern83is provided in the end portion of the first surface71ato suppress limiting the arrangement of the components and wirings of the first circuit board71including the flash memories43and the controller44.

The top cover52has the extension portion131fthat is connected to the end portion of the first covering portion131acovering the first surface71aand extends in the direction along the first surface71a. The extension portion131fis thermally connected to the first conductor pattern83by the first heat conduction sheet88. Due to this, it is easy to secure a large contact area between the top cover52, the first heat conduction sheet88, and the first conductor pattern83, and heat can be transmitted from the first conductor pattern83to the top cover52more efficiently.

The plurality of first vias87connect the first conductor layer82and the first conductor pattern83. That is, since a plurality of heat transmission paths is provided between the first conductor layer82and the first conductor pattern83, the heat generated from the flash memory43can be transmitted to the top cover52more efficiently. Thus, the heat generated from the flash memory43is radiated by the top cover52and a rise in the temperature inside the case41is suppressed.

The gap G is formed between at least a portion of the controller cover111of the top cover52thermally connected to the controller44that generates a larger amount of heat and the memory cover112thermally connected to the flash memory43. Due to this, the heat transmitted from the controller44to the controller cover111is suppressed from being transmitted to the flash memory43via the memory cover112.

The controller cover111has the fins127provided on the outer face111b. Due to this, the heat transmitted from the controller44to the controller cover111is more easily cooled by the outside air in the module case21, and the heat of the controller cover111is suppressed from being transmitted to the flash memory43via the memory cover112.

The fin127extends in the direction along the flow of air created by the fan25. Due to this, the heat transmitted from the controller44to the controller cover111is cooled more efficiently, and the heat of the controller cover111is suppressed from being transmitted to the flash memory43via the memory cover112.

The memory cover112is attached to the controller cover111. Due to this, during assembling of the SSD26, for example, the memory cover112and the controller cover111can be treated as an integrated member and the SSD26can be assembled easily.

The controller cover111that receives heat from the controller44that generates a larger amount of heat is disposed closer to the external connector47than the memory cover112. Due to this, the heat of the controller cover111is likely to be transmitted to the module substrate22and the module case21via the external connector47. As a result, the heat transmitted from the controller44to the controller cover111is further suppressed from being transmitted to the flash memory43via the memory cover112.

The controller cover111overlaps the external connector47in the thickness direction of the circuit board42. Due to this, the heat of the controller cover111is more easily transmitted to the module substrate22and the module case21via the external connector47. As a result, the heat transmitted from the controller44to the controller cover111is further suppressed from being transmitted to the flash memory43via the memory cover112.

The protruding portion123of the top cover52passes through the opening106of the first circuit board71and is thermally connected to the controller44that generates a larger amount of heat than the flash memory43by the fourth heat conduction sheet125. The heat generated from the controller44is transmitted to the top cover52via the fourth heat conduction sheet125. As a result, the heat generated from the controller44is radiated by the top cover52. Further, the controller44can be mounted on the third surface72aof the second circuit board72. Thus, a decrease in the degree of freedom in the arrangement of the flash memories43and the controller44in the SSD26is suppressed and an increase in the thickness of the SSD26is suppressed.

The controller44is longer than the flash memory43in the direction in which the third surface72aof the second circuit board72faces. The opening106is formed at the position overlapping the controller44. Due to this, the first circuit board71is suppressed from interfering the controller44, and limiting the distance between the first circuit board71and the second circuit board72is suppressed.

When seen in a plan view from the direction in which the third surface72afaces, the controller44is surrounded by the edges of the first circuit board71, which form the opening106. Thus, the first circuit board71is suppressed from interfering the controller44and limiting the distance between the first circuit board71and the second circuit board72is suppressed.

At least one of the flash memories43is thermally connected to the bottom cover53by the sixth heat conduction sheet141. The heat generated from the flash memory43is transmitted to the bottom cover53. As a result, the heat generated from the flash memory43is radiated by the bottom cover53.

The fifth heat conduction sheet135connects the flash memory43and the case41thermally. As a result, the heat generated from the flash memory43is also radiated by the case41.

The first and second circuit boards71and72are attached to the frame51and the top cover52is also attached to the frame51. Due to this, when external force is applied to the top cover52, deformation of the first and second circuit boards71and72is suppressed.

Some of the plurality of flash memories43mounted on the first circuit board71are adjacent to the controller44in the plan view from the thickness direction of the first circuit board71. However, since the first circuit board71is separated from the second circuit board72in the thickness direction of the first circuit board71(the direction along the Z-axis), the temperature of the flash memories43mounted on the first circuit board71is rarely increased by the controller44.

The first and second substrate connectors101and102are interposed between the controller44and the flash memory43on the third surface72aof the second circuit board72. In other words, the first and second substrate connectors101and102separate the region in which the controller44is mounted from the region in which the flash memory43is mounted. Due to this, the heat generated from the controller44is suppressed from heating the flash memory43via the air inside the case41.

The controller44is disposed closer to the external connector47than the flash memory43. Further, the controller cover111is disposed closer to the external connector47than the memory cover112. That is, portions of which the temperature is more likely to increase are disposed at positions close to the external connector47. Thus, the heat generated from the controller44, for example, is suppressed from being transmitted to the flash memory43by being transmitted to the module case21via the external connector47.

The plurality of capacitors46extend in the direction in which the first circuit board71extends (the direction along the Y-axis). Due to this, it is easy to further decrease the thickness of the SSD26(the length in the direction along the Z-axis).

In the second surface71bof the first circuit board71, the plurality of pads75on which the flash memory43is not mounted are exposed. In this manner, the second surface71bmay be selected with the highest priority as a face on which the flash memory43is not mounted and the exposed pads75are provided among the first to fourth surfaces71a,71b,72a, and72bof the first and second circuit boards71and72. Further, the third surface72amay be selected with the next highest priority as the face on which the exposed pads75are provided. Since the first and fourth surfaces71aand72bface the outer side of the SSD26, the first and fourth surfaces71aand72bare thermally connected to the case41easily by the fifth and sixth heat conduction sheets135and141, for example. Due to this, the flash memories43mounted on the first and fourth surfaces71aand72bcan be more easily cooled than the flash memories43mounted on the second and third surfaces71band72a.

In the first embodiment, the fins127are provided on the outer face111bof the controller cover111. However, the fins127may be provided on at least one of the outer face111bof the controller cover111and the outer face131hof the covering member131of the memory cover112without being limited to the surface.

FIG. 7is a perspective view illustrating a disk array storage7as a modified example of the first embodiment. In the first embodiment, the SSD26is provided in the server module5of the data center1. However, the SSD26may be provided in another system and apparatus such as the disk array storage7.

The plurality of SSDs26are inserted in the disk array storage7. The disk array storage7is used as an integrated storage system or storage apparatus having the plurality of SSDs26. That is, the disk array storage7is a storage system having a plurality of flash memories43provided in each of the plurality of SSDs26.

Hereinafter, a second embodiment will be described with reference toFIG. 8. In description of following embodiments, constituent elements having the same functions as the constituent elements that have been described already may be denoted by the same reference numerals as the already-described constituent elements, and description thereof may be omitted. Moreover, a plurality of constituent elements denoted by the same reference numeral may not have the same functions and properties but may have different functions and properties depending on the respective embodiments.

FIG. 8is a cross-sectional view illustrating the SSD26according to the second embodiment. As illustrated inFIG. 8, the first conductor pattern83of the first circuit board71of the second embodiment is provided substantially in the central portion of the first surface71a. The first conductor pattern83is formed at a position overlapping the first substrate connector101in the thickness direction of the first circuit board71.

The second projected portion132cof the protruding member132of the memory cover112makes contact with the first conductor pattern83provided substantially in the central portion of the first surface71awith an insulating heat conduction sheet interposed, for example. In other words, the second projected portion132cis thermally connected to the position of the first surface71aoverlapping the first substrate connector101in the direction in which the first surface71afaces (the direction along the Z-axis).

In the SSD26of the second embodiment, the first conductor pattern83is provided at the position overlapping the first substrate connector101that connects the first circuit board71to the second circuit board72in the thickness direction of the first circuit board71. Due to this, the heat of the second circuit board72is transmitted to the first circuit board71via the first and second substrate connectors101and102. The heat transmitted to the first circuit board71is transmitted to the top cover52from the first conductor layer82via the first conductor pattern83. As a result, the heat generated from the second circuit board72is radiated by the top cover52, and a rise in the temperature inside the case41is suppressed.

The second projected portion132cof the case41is thermally connected to the position of the first surface71aoverlapping the first substrate connector101in the direction in which the first surface71afaces. Due to this, the heat generated from the controller44is transmitted to the second projected portion132cvia the second circuit board72, the second substrate connector102, the first substrate connector101, and the first circuit board71. As a result, the heat generated from the controller44is radiated by the case41via the first and second substrate connectors101and102.

The first circuit board71and the first substrate connector101are held between the second projected portion132cand the second substrate connector102. As a result, the first circuit board71is suppressed from bending at the position at which the first substrate connector101is disposed.

The first substrate connector101is disposed substantially in the central portion of the first circuit board71in the direction in which the first circuit board71extends. The first substrate connector101and the first circuit board71are held between the second projected portion132cand the second substrate connector102. That is, substantially the central portion of the first circuit board71is held. Therefore, bending of the first circuit board71is further suppressed. Further, a each length of wiring between the plurality of flash memories43mounted on the first and second circuit boards71and72and the controller44mounted on the second circuit board72is suppressed from varying greatly.

At least one of the flash memories43is mounted at the position of the fourth surface72bof the second circuit board72overlapping the second substrate connector102in the direction in which the fourth surface72bfaces. Due to this, the heat generated from the flash memory43is transmitted to the second projected portion132cvia the second circuit board72, the second substrate connector102, the first substrate connector101, and the first circuit board71. As a result, the heat generated from the flash memory43is radiated by the case41via the first and second substrate connectors101and102.

Hereinafter, a third embodiment will be described with reference toFIG. 9.FIG. 9is a cross-sectional view illustrating the SSD26according to the third embodiment. As illustrated inFIG. 9, the top cover52of the third embodiment includes the controller cover111, the memory cover112, and a heat insulating material171. The heat insulating material171may be also referred to as an interposed portion, an intermediate portion, an isolating portion, a sealing portion, a portion, and a member, for example.

The heat insulating material171is made of a synthetic resin, for example. The heat insulating material171is not limited to this, and for example, may be made of another material such as ceramics. A heat conductivity of the heat insulating material171is lower than a heat conductivity of the controller cover111. Further, the heat conductivity of the heat insulating material171is lower than the heat conductivity of the memory cover112.

The heat insulating material171is interposed between the controller cover111and the memory cover112. For example, the heat insulating material171is interposed between the outer face111bof the controller cover111and the second edge portion131cof the memory cover112and closes the gap G between the controller cover111and the memory cover112. The heat insulating material171may be attached to the controller cover111and the memory cover112by a heat insulating adhesive, for example, and may be fixed to the controller cover111and the memory cover112by the screws113.

In the SSD26of the third embodiment, the heat insulating material171having a lower heat conductivity than the memory cover112and the controller cover111is interposed between the memory cover112and the controller cover111. Due to this, the heat transmitted from the controller44to the controller cover111is further suppressed from being transmitted to the flash memory43via the memory cover112.

Hereinafter, a fourth embodiment will be described with reference toFIG. 10.FIG. 10is a cross-sectional view illustrating the SSD26according to the fourth embodiment. As illustrated inFIG. 10, the first heat radiating portion121of the controller cover111of the fourth embodiment has a thermal connecting portion121b.

The thermal connecting portion121bis provided in one end portion of the first heat radiating portion121in the direction along the Y-axis. The end portion of the first heat radiating portion121in which the thermal connecting portion121bis provided faces the same direction as the direction in which the external connector47faces. The arrangement of the thermal connecting portion121bis not limited to this.

The external connector47of the SSD26is connected to a module connector181that is provided in the front panel27of the module case21, for example. The SSD26connected to the module connector181is supported by the module connector181and a supporting portion provided in the module case21, for example.

The thermal connecting portion121bof the first heat radiating portion121extends along the front panel27. A seventh heat conduction sheet183is interposed between the thermal connecting portion121band the front panel27. The seventh heat conduction sheet183may be also referred to as a heat transfer member, for example. The seventh heat conduction sheet183connects the thermal connecting portion121bof the controller cover111and the front panel27of the module case21thermally. The seventh heat conduction sheet183has higher elasticity than the controller cover111and has higher elasticity than the front panel27. The seventh heat conduction sheet183is elastically compressed between the controller cover111and the front panel27and is stuck to the controller cover111and the front panel27.

In the data center1of the fourth embodiment, the controller cover111of the case41of the SSD26is thermally connected to the module case21of the data center1. Due to this, the heat transmitted from the controller44to the controller cover111is easily cooled by the outside air of the server module5via the module case21, and the heat of the controller cover111is suppressed from being transmitted to the flash memory43via the memory cover112.

According to at least one embodiment described hereinabove, a protruding portion provided in a housing is configured to pass through an opening provided in a first substrate so as to be thermally connected to an electronic component mounted on a second substrate. Due to this, the heat generated from the electronic component is radiated by a portion of the housing, which covers the first substrate.