1. Field of the Invention
The present invention relates to a semiconductor device including a multi-layered structure mounted on a package board, the multi-layered structure including a semiconductor chip and a print wiring board fixed to the semiconductor chip through an insulating layer.
Priority is claimed on Japanese Patent Application No. 2009-019931, filed Jan. 30, 2009, the content of which is incorporated herein by reference.
2. Description of the Related Art
Recently, demands for smaller and thinner semiconductor devices have been increasing with the recent high-density packaging. To meet the demands, a semiconductor device having a multi-layered structure in which multiple semiconductor chips are stacked on a package board has been proposed.
As an example of a general multi-layered structure of semiconductor chips,
On the other hand, in a case of DRAM (Dynamic Random Access Memory) having a structure in which electrode pads are aligned in the center region of a semiconductor chip, the electrode pads on the semiconductor chip have to be connected to connection lands on a package board using relatively long wires. For this reason, the spacer 102 cannot be provided between the upper and lower semiconductor chips 101a and 101b.
Japanese Patent Laid-Open Publication No. 2004-312008 discloses such a multi-layered structure of semiconductor chips in which electrode pads are aligned in the center region of the semiconductor chip. Specifically, as shown in
Japanese Patent Laid-Open Publication No. 2001-085609 discloses a similar structure. Specifically, as shown in
In this case, a circuit is formed on the bottom surface of the package board 300 using wires thicker than the wires 305a and 305b. However, the signal and power electrode pads 302b on the top surface of the semiconductor chip 301b are connected to the connection lands 304b using the long wires 305b, thereby causing the larger impedance, noises, or a voltage drop, and preventing high-speed operation.
Japanese Patent Laid-Open Publication No. 2006-165303 discloses a multi-layered structure for reducing the power impedance. Specifically, as shown in
Electrode pads 406 on a top surface of each semiconductor chip 400 are connected by flip-chip connection to connection lands 407 on a lower surface of the corresponding print wiring board 402. Connection lands 409 aligned along opposing sides of each print wiring board 402 are connected by wire-bonding to connection lands 410 on the package board 400 using wires 411.
In this case, signal and power wirings on the bottom surface of the print wiring board 402 are extended from the center region to the peripheral region of the print wiring board 402. Consequently, the power impedance can be further reduced than when the electrode pads 203 and 302b on the semiconductor chips 202a, 202b, and 301b shown in
Regarding the signal impedance, however, wires are present close to the circuit on the top surface of the semiconductor chip 400, thereby causing larger capacity, and therefore causing an operational problem with respect to signal wirings.
Japanese Patent Laid-Open Publication No. 2004-071997 discloses a multi-chip package in which a silicon board having a metal film on a top surface thereof is provided between two stacked semiconductor chips so that a potential is applied to a bottom surface of the upper semiconductor chip through the metal film.
For the above reasons, a multi-layered structure of semiconductor chips achieving faster operation by reducing resistance and inductance for a power wiring circuit requiring a reduction in impedance and by reducing capacity for a signal wiring circuit requiring a reduction in capacity is required.
In one embodiment, a semiconductor device includes a package board, first connectors, and a first multi-layered structure. The package board has first and second regions. The first connectors are in the first region. The first multi-layered structure includes a first semiconductor chip, a wiring board, and second to fifth connectors. The first semiconductor chip has first and second surfaces. The first surface covers the second region. The wiring board has third and fourth surfaces. The third surface is fixed to the second surface. The second to fourth connectors are in the center regions of the second to fourth surfaces, respectively. The fifth connectors are aligned along two opposing sides of the fourth surface. The second connectors electrically connect to the third connectors. The third connectors electrically connect to the fourth and fifth connectors. The first connectors electrically connect to the fourth and fifth connectors.
Accordingly, the semiconductor device can reduce the capacity for a signal wiring circuit requiring a reduction in capacity, and reduce the resistance and the inductance for a power wiring circuit requiring a reduction in impedance, thereby preventing noises and a voltage drop, and therefore achieving faster operation.
The above features and advantages of the present invention will be more apparent from the following description of certain preferred embodiments taken in conjunction with the accompanying drawings, in which:
The present invention will now be described herein with reference to illustrative embodiments. The accompanying drawings explain a semiconductor device and a method of manufacturing the semiconductor device in the embodiments. The size, the thickness, and the like of each illustrated portion might be different from those of each portion of an actual semiconductor device.
Those skilled in the art will recognize that many alternative embodiments can be accomplished using the teachings of the present invention and that the present invention is not limited to the embodiments illustrated herein for explanatory purposes.
Hereinafter, a semiconductor device 1 according to a first embodiment of the present invention is explained.
The semiconductor device 1 includes: a package board 2; a multi-layered structure 3 on the package board 2; a seal 4 made of mold resin covering the multi-layered structure 3 and an upper surface of the package board 2; and solder balls 5 on a bottom surface of the package board 2. Thus, the semiconductor device 1 has a BGA (Ball Grid Array) structure.
The package board 2 is made of a print wiring board that is rectangular in plane view (i.e., when viewed in a direction perpendicular to the top and bottom surfaces thereof). The top surface of the package substrate 2 has a mounting region 2a in which the multi-layered structure 3 is mounted. Multiple signal and power connection lands 6a and 6b are aligned along the mounting region 2a.
The connection lands 6a and 6b are aligned in straight lines along two opposing sides of the multi-layered structure 3 as shown in
Although not shown, vias, a wiring pattern, and the like for electrically connecting the connection lands 6a and 6b to the corresponding solder balls 5 are provided in the package board 2.
The multi-layered structure 3 includes: a semiconductor chip 7 fixed to the mounting region 2a of the package board 2 through an insulating adhesive 10; and a print wiring board 9 fixed to the semiconductor chip 7 through an insulating resin layer 8.
The semiconductor chip 7 is rectangular in the plane view. The semiconductor chip 7, the print wiring board 9, and the insulating resin layer 8 have substantially the same size in the plane view. The semiconductor chip 7 is connected by a flip-chip connection to the print wiring board 9, thereby reducing the size of the multi-layered structure 3 in the height direction.
Specifically, multiple signal electrode pads 11a and multiple power electrode pads 11b are aligned in a straight line in the center region of the top surface of the semiconductor chip 7. Since the signal electrode pads 11a and the power (VDD, VDDQ, VSS, VSSQ) electrode pads 11b that are aligned in a straight line cannot be simultaneously illustrated in
Multiple signal connection lands 12a and multiple power connection lands 12b are aligned in a straight line in the center region of the bottom surface of the print wiring board 9 so as to face the electrode pads 11a and 11b on the top surface of the semiconductor chip 7, respectively, as shown in
As shown in
As shown in
The power connection lands 14b are aligned in straight lines along two opposing sides of the print wiring board 9. Since the signal-and-power connection lands 14a and 14b cannot be simultaneously illustrated in
The signal connection pads 14a on the top surface of the print wiring board 9 are electrically connected to the signal connection lands 12a on the bottom surface of the print wiring board 9 through conductors 15 called vias penetrating the print wiring board 9 (this structure is called a “pad-on-via structure”). Thus, the signal wiring circuit is formed.
The power connection lands 14b are aligned in straight lines along two opposing sides of the print wiring board 9. The power connection lands 14b are electrically connected (inter-layer connection) to a wiring portion 17 on the bottom surface of the print wiring board 9 through conductors 16 called vias penetrating the print wiring board 9.
Specifically, as shown in
The power connection lands 14b on the top surface of the print wiring board 7 are electrically connected to the power connection lands 12b on the bottom surface of the print wiring board 9 through the conductors 16 and the wiring portion 17. Thus, the power wiring circuit is formed.
As shown in
On the other hand, regarding the power wiring circuit, the power connection lands 14b aligned along the two opposing sides of the print wiring board 9 are electrically connected (wire-bonding connection) to the power connection lands 6b aligned along the two opposing sides of the package board 2 using relatively short wires 18b.
Although it is illustrated in
In
According to the semiconductor device 1, regarding the signal wiring circuit of the multi-layered structure 3, the connection lands 14a in the center region of the print wiring board 9 are connected to the connection lands 6a on the package board 2 using the relatively long wires 18a, thereby enabling a reduction in capacity.
On the other hand, regarding the power wiring circuit of the multi-layered structure 3, the connection lands 14b aligned along the two opposing sides of the print wiring board 9 are connected to the connection lands 6b on the package board 2 using the relatively short wires 18b while the wiring portion 17 (conductive patterns 17a and 17b) on the bottom surface of the print wiring board 9 has a large width, thereby enabling a reduction in the resistance and in the inductance.
Accordingly, the semiconductor device 1 can reduce the capacity for the signal wiring circuit requiring a reduction in capacity, and reduce the resistance and the inductance for the power wiring circuit requiring a reduction in the impedance, thereby preventing noises and a voltage drop, and therefore achieving faster operation.
Hereinafter, a semiconductor device 20 according to a second embodiment of the present invention is explained with reference to
Each of the multi-layered structures 21A and 21B has the same structure as that of the multi-layered structure 3. Other elements have substantially the same structures as those of the semiconductor device 1.
For this reason, explanations of the same elements as those of the semiconductor device 1 are omitted hereinafter, and like reference numerals denote like elements between the first and second embodiments.
Similar to the semiconductor device 1, according to the semiconductor device 20, regarding the signal wiring circuit of the multi-layered structures 21A and 21B, the connection lands 14a in the center region of the print wiring board 9 are connected to the connection lands 6a on the package board 2 using the relatively long wires 18a, thereby enabling a reduction in capacity.
On the other hand, regarding the power wiring circuit of the multi-layered structures 21A and 21B, the connection lands 14b aligned along the two opposing sides of the print wiring board 9 are connected to the connection lands 6b on the package board 2 using the relatively short wire 18b while the wiring portion 17 (conductive patterns 17a and 17b) on the bottom surface of the print wiring board 9 has a large width, thereby enabling a reduction in the resistance and in the inductance.
Accordingly, the semiconductor device 20 can reduce the capacity for the signal wiring circuit requiring a reduction in capacity, and reduce the resistance and the inductance for the power wiring circuit requiring a reduction in the impedance, thereby preventing noises and a voltage drop, and therefore achieving faster operation.
Hereinafter, a semiconductor device 30 according to a third embodiment of the present invention is explained with reference to
The semiconductor device 30 has substantially the same structure as those of the semiconductor devices 1 and 20 except that the wiring portion 17A is provided on the top surface of the print wiring board 9 while the wiring portion 17 of the semiconductor devices 1 and 20 is provided on the bottom surface of the print wiring board 9.
For this reason, explanations of the same elements as those of the semiconductor devices 1 and 20 are omitted hereinafter, and like reference numerals denote like elements among the first to third embodiments.
Although not shown, the wiring portion 17A on the top surface of the print wiring board 9 includes conductive patterns corresponding to the power wirings (VDD and VDDQ) and conductive patterns corresponding to the ground wirings (VSS and VSSQ).
The power connection lands 14b aligned along two opposing sides of the print wiring board 9 are electrically connected (inter-layer connection) to the power connection lands 12b through conductors called vias penetrating the print wiring board 9. On the other hand, the signal connection pads 14a are electrically connected (inter-layer connection) to the signal connection lands 12a through conductors called vias penetrating the print wiring board 9.
Similar to the semiconductor devices 1 and 20, according to the semiconductor device 30, regarding the signal wiring circuits of the multi-layered structures 31A and 31B, the connection lands 14a in the center region of the print wiring board 9 are connected to the connection lands 6a on the package board 2 using the relatively long wires 18a, thereby enabling a reduction in capacity.
On the other hand, regarding the power wiring circuits of the multi-layered structures 31A and 31B, the connection lands 14b aligned along the two opposing sides of the print wiring board 9 are connected to the connection lands 6b on the package board 2 using the relatively short wire 18b while the wiring portion 17A on the top surface of the print wiring board 9 has a large width, thereby enabling a reduction in the resistance and in the inductance.
Accordingly, the semiconductor device 30 can reduce the capacity for the signal wiring circuit requiring a reduction in capacity, and reduce the resistance and the inductance for the power wiring circuit requiring a reduction in the impedance, thereby preventing noises and a voltage drop, and therefore achieving faster operation.
Hereinafter, a semiconductor device 40 according to a fourth embodiment of the present invention is explained with reference to shown in
The semiconductor device 40 has substantially the same structures as those of the semiconductor devices 1, 20, and 30 except that wiring portions 17A and 17B are provided on both top and bottom surfaces of the print wiring board 9, respectively. For this reason, explanations of the same elements as those of the semiconductor devices 1, 20, and 30 are omitted hereinafter, and like reference numerals denote like elements among the first to fourth embodiments.
Similar to the semiconductor devices 1, 20, and 30, according to the semiconductor device 40, regarding the signal wiring circuits of the multi-layered structures 41A and 41B, the connection lands 14a in the center region of the print wiring board 9 are connected to the connection lands 6a on the package board 2 using the relatively long wires 18a, thereby enabling a reduction in capacity.
On the other hand, regarding the power wiring circuits of the multi-layered structures 41A and 41B, the connection lands 14b aligned along the two opposing sides of the print wiring board 9 are connected to the connection lands 6b on the package board 2 using the relatively short wire 18b while the wiring portions 17A and 17B on the top and bottom surfaces of the print wiring board 9 have a large width, thereby enabling a reduction in the resistance and in the inductance.
Accordingly, the semiconductor device 40 can reduce the capacity for the signal wiring circuit requiring a reduction in capacity, and reduce the resistance and the inductance for the power wiring circuit requiring a reduction in the impedance, thereby preventing noises and a voltage drop, and therefore achieving faster operation.
Hereinafter, a semiconductor device 50 according to a fifth embodiment of the present invention is explained with reference to
The semiconductor device 50 has substantially the same structures as those of the semiconductor devices 1 and 20 except for the following. Each of the multi-layered structures 51A and 51B includes the signal connection lands 14a aligned in two straight lines in the center region of the top surface of the print wiring board 9.
Additionally the two lines of the signal connection lands 14a are electrically connected to a wiring portion 17C on the bottom surface of the print wiring board 9 through conductors 15A. Further, the two lines of the signal connection lands 14a are electrically connected to the signal connection lands 12a through the wiring portion 17C.
For this reason, explanations of the same elements as those of the semiconductor devices 1 and 20 are omitted hereinafter, and like reference numerals denote like elements among the first, second, and fifth embodiments.
Similar to the semiconductor devices 1 and 20, according to the semiconductor device 50, regarding the signal wiring circuits of the multi-layered structures 51A and 51B, the connection lands 14a in the center region of the print wiring board 9 are connected to the connection lands 6a on the package board 2 using the relatively long wires 18a, thereby enabling a reduction in capacity.
On the other hand, regarding the power wiring circuits of the multi-layered structures 51A and 51B, the connection lands 14b aligned along the two opposing sides of the print wiring board 9 are connected to the connection lands 6b on the package board 2 using the relatively short wire 18b while the wiring portion 17 (conductive patterns 17a and 17b) on the bottom surface of the print wiring board 9 has a large width, thereby enabling a reduction in the resistance and in the inductance.
Accordingly, the semiconductor device 50 can reduce the capacity for the signal wiring circuit requiring a reduction in capacity, and reduce the resistance and the inductance for the power wiring circuit requiring a reduction in the impedance, thereby preventing noises and a voltage drop, and therefore achieving faster operation.
Hereinafter, a semiconductor device 60 according to a sixth embodiment of the present invention is explained with reference to
Additionally, signal-and-power connection pads 62 are provided on a bottom surface of the lower semiconductor chip 7b, while connecting to signal-and-power connection pads 63 on the bottom surface of the package board 2 through wires 64 passing through an opening in the package board 2. Other elements have the same structure as those of the semiconductor device 1.
For this reason, explanations of the same elements as those of the semiconductor device 1 are omitted hereinafter, and like reference numerals denote like elements among the first and sixth embodiments.
Similar to the semiconductor device 1, according to the semiconductor device 60, regarding the signal wiring circuit of the multi-layered structure 61, the connection lands 14a in the center region of the print wiring board 9 are connected to the connection lands 6a on the package board 2 using the relatively long wires 18a, thereby enabling a reduction in capacity.
On the other hand, regarding the power wiring circuit of the multi-layered structure 61, the connection lands 14b aligned along the two opposing sides of the print wiring board 9 are connected to the connection lands 6b on the package board 2 using the relatively short wire 18b while the wiring portion 17 (conductive patterns 17a and 17b) on the bottom surfaces of the print wiring board 9 has a large width, thereby enabling a reduction in the resistance and in the inductance.
Accordingly, the semiconductor device 60 can reduce the capacity for the signal wiring circuit requiring a reduction in capacity, and reduce the resistance and the inductance for the power wiring circuit requiring a reduction in the impedance, thereby preventing noises and a voltage drop, and therefore achieving faster operation.
It is apparent that the present invention is not limited to the above embodiments, but may be modified and changed without departing from the scope and spirit of the invention.
For example, the number of multi-layered structures stacked on the package board 2, and the number of semiconductor chips stacked in each of the multi-layered structures can be appropriately modified.
The present invention is applicable to a semiconductor device, such as DRAM, which includes a multi-layered structure mounted on a package board, the multi-layered structure including a semiconductor chip and a print wiring board fixed to the semiconductor chip through an insulating layer.
Additionally, the present invention is applicable to various semiconductor devices, such as a data processor or ROM (Read Only Memory).
Number | Date | Country | Kind |
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2009-019931 | Jan 2009 | JP | national |