1. Field of the Invention
The present invention relates to a semiconductor chip and a semiconductor device having the semiconductor chip.
2. Description of Related Art
In recent years, along with downsizing of electronic devices or the like having a semiconductor device incorporated therein, there has been a strong demand for downscaling of semiconductor devices. In connection to this demand, there has been a development of a semiconductor device in which a plurality of semiconductor chips are stacked and these semiconductor chips are connected by using through silicon vias. For example, Japanese Patent Application Laid-open No. 2011-82450 discloses a semiconductor device in which a plurality of semiconductor chips are connected by through silicon vias (TSVs) each penetrating a silicon semiconductor substrate.
In some of semiconductor devices in which a plurality of semiconductor chips are connected by through silicon vias, an area where a plurality of through silicon vias are arranged in an array manner is provided. Such an area is called as a through-silicon-via array area in the following explanation. The through-silicon-via array area includes an insulation layer or a wiring layer which has a possibility that cracks are generated therein at the time of stacking the semiconductor chips. Since such cracks can be a cause of a failure of the semiconductor device, it is necessary to detect the presence of cracks in the through-silicon-via array area before shipment of semiconductor devices as products.
As a technique of detecting cracks that are generated on semiconductor chips, there has been proposed a semiconductor device in which a wire for detecting cracks is arranged along the entire outer periphery of a semiconductor chip. Each ends of the wire is connected to a pad which an external tester is brought into contact with. According to the semiconductor device, it becomes possible to detect cracks generated on the semiconductor chips by detecting a variation of a resistance value between the pads (see, for example, Japanese Patent Application Laid-open No. 2009-54862).
However, what the method described in Japanese Patent Application Laid-open No. 2009-54862 can detect are only cracks generated on an outer periphery part of a semiconductor chip, that is, an edge part of the semiconductor chip, and the method cannot detect cracks generated at portions other than an outer periphery part of a semiconductor chip.
The above-mentioned through-silicon-via array area is occasionally formed on a position other than an outer periphery part of a semiconductor chip, such as a central part of the semiconductor chip. Therefore, there has been a demand of a technique of detecting cracks generated on a position other than an outer periphery part of the semiconductor chip in order to detect cracks generated on the through-silicon-via array area.
In one embodiment, there is provided a semiconductor device that includes at least one semiconductor chip, the semiconductor chip including: a plurality of penetration electrodes each penetrating between main and back surfaces of the semiconductor chip, the penetration electrodes including a plurality of first penetration electrodes, a second penetration electrode and a third penetration electrode; and a wiring structure including at least one first wiring segment configured to intersect with a plurality of regions, each of the regions being defined as a region between corresponding two of the first penetration electrodes, one end of the first wiring segment being electrically coupled to the second penetration electrode, the other end of the first wiring segment being electrically coupled to the third penetration electrode such that an electrical current flows between the second and third penetration electrodes through the first wiring segment of the wiring structure.
In another embodiment, there is provided a semiconductor device that includes at least one semiconductor chip, the semiconductor chip including: a plurality of penetration electrodes each penetrating between main and back surfaces of the semiconductor chip, the penetration electrodes including a plurality of first penetration electrodes, a second penetration electrode and a third penetration electrode; and a wiring structure including a first terminal coupled to the second penetration electrode, a second terminal coupled to the third penetration electrode and a plurality of middle wirings coupled in series between the first and second terminals to make an electrical path between the second and third penetration electrodes, each of the middle wirings elongating such that each of the middle wirings threads its way through corresponding ones of the first penetration electrodes.
The following detailed description refers to the accompanying drawings that show, by way of illustration, specific aspects and embodiments in which the present invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the present invention. Other embodiments may be utilized, and structure, logical and electrical changes may be made without departing from the scope of the present invention. The various embodiments disclosed herein are not necessarily mutually exclusive, as some disclosed embodiments can be combined with one or more other disclosed embodiments to form new embodiments.
A semiconductor chip and a semiconductor device according to the present invention will be explained below with reference to the drawings. The drawings used in the following explanations are for explaining configurations of embodiments of the present invention, and the size, thickness, and dimensions of respective elements shown in the drawings may be shown differently from an actual dimensional relationship between these elements. Furthermore, materials or the like exemplified in the following explanations are only examples. The present invention is not necessarily limited to these examples, and these examples can be modified as appropriate without changing the scope of the invention.
As shown in
As the package substrate 2, a circuit substrate made of resin in which a re-wiring layer is formed, such as an interposer, can be used. The external terminals 7 formed on the rear face of the package substrate 2 are electrically connected to the corresponding group of terminals of the semiconductor chips C0 to C4 stacked on the surface of the package substrate 2 via the re-wiring layer formed in the package substrate 2. As shown in
The semiconductor chip C0 that is arranged nearest to the package substrate 2 is a controller chip (System On Chip; SOC) that controls the semiconductor device 1. The semiconductor chips C1, C2, C3, and C4 stacked on the semiconductor chip C0 are memory chips including a DRAM for example. Each of the semiconductor chips C1 to C4 is greater in size than the semiconductor chip C0.
The semiconductor device 1 shown in
It is possible to configure that the semiconductor chips C1 to C4 communicate with each other under control of the semiconductor chip C0. For example, this configuration is useful for copying of data between the chips and for data processing between the chips that is related to data processing in the semiconductor chip C0. Furthermore, each of the semiconductor chips C1 to C4 can be connected with outside via the semiconductor chip C0 and the external terminal 7 under control of the semiconductor chip C0.
In the first embodiment, explanations have been made with an example of a stacked semiconductor device constituted by five semiconductor chips, that is, the semiconductor chip C0 and four semiconductor chips C1, C2, C3, and C4 stacked thereon. However, it suffices as far as the semiconductor device according to the present invention is a semiconductor device in which a plurality of semiconductor chips including the semiconductor chip according to the present invention are electrically connected to each other via through silicon vias, and the semiconductor device is not limited to the example shown in
Electrical connection among the semiconductor chips C0, C1, C2, C3, and C4 in the semiconductor device 1 according to the first embodiment is explained next with reference to
The through silicon via TSV1 shown in
Therefore, an input signal (a command signal, an address signal, a clock signal, and the like) supplied to the current path from outside via the bottom surface C1a of the semiconductor chip C1 is commonly input to the internal circuits 5 of the semiconductor chips C1 to C4. Furthermore, an output signal (data and the like) supplied to the current path from the internal circuit 5 of each of the semiconductor chips. C1 to C4 undergoes a wired-OR operation, and is output to outside from the bottom surface C1a of the semiconductor chip C1.
The through silicon via TSV2 shown in
As described above, the through silicon vias 15 provided in the semiconductor chips C1 to C4 include two types of through silicon vias shown in
Next, an outline of a crack check control circuit, which generates a crack check enable signal TE used at the time of conducting an operation for detecting whether cracks are generated around the through silicon vias 15, is explained with reference to
For the brevity of explanations, as signals input to each of the semiconductor chips, only a test command tCMD, a test address signal tADD, a test clock signal tCK, a test-chip select signal tCS1-tCS4, and a test-clock enable signal tCKE1-tCKE4, which are signals related to the crack check enable signal TE, are shown in
As shown in
Furthermore, each of the semiconductor chips C1 to C4 includes a plurality of control-signal input terminals tIT2 that receive the test-chip select signal tCS1-tCS4. The control-signal input terminals tIT2 of the semiconductor chips C1 to C4 are connected to each other via the through silicon via TSV2 of the type shown in
Each of the semiconductor chips C1 to C4 further includes a plurality of control-signal input terminals tIT3 that receive the test-clock enable signal tCKE1-tCKE4. The control-signal input terminals tIT3 of the semiconductor chips C1 to C4 are connected to each other via the through silicon via TSV2 of the type shown in
The crack check enable signals TE1 to TE4 of the semiconductor chips C1 to C4 are configured to be selectively activated (supplied) only when the corresponding semiconductor chip is a check target. This configuration is realized by supplying the test command tCMD that indicates generation of the crack check enable signal TE, the test address signal tADD, and the test clock signal tCK in a state where the test-chip select signal tCS and the test-clock enable signal tCKE are selectively supplied to a semiconductor chip as a check target.
According to the semiconductor device 1 of the first embodiment, because the crack check enable signal TE can be selectively supplied to a semiconductor chip as a check target, it is possible to conduct a check only on the semiconductor chip as a check target even if the test terminals (first terminals), each of which is an end of a crack check wire 18 (details thereof will be described later) provided in each of the plurality of semiconductor chips, is connected each other, that is, the test terminals are connected to each other by the through silicon via TSV1 of the type shown in
In a state where only the semiconductor chips C1 to C4 as memory chips are stacked, the test command tCMD, the test address signal tADD, the test clock signal tCK, the test-chip select signal tCS, and the test-clock enable signal tCKE can be supplied from a predetermined testing pad provided on the semiconductor chip C1.
Furthermore, in a state where the semiconductor chips C1 to C4 and the semiconductor chip C0 as a controller chip are stacked, the test command tCMD, the test address signal tADD, the test clock signal tCK, the test-chip select signal tCS, and the test-clock enable signal tCKE can be supplied from the external terminal 7 via the semiconductor chip C0. In this case, it is possible to supply the test command tCMD, the test address signal tADD, the test clock signal tCK, the test-chip select signal tCS, and the test-clock enable signal tCKE to the semiconductor chips C1 to C4 as memory chips after performing predetermined arithmetic processing on a signal supplied from outside on the semiconductor chip C0. Alternatively, it is possible to supply the semiconductor chips C1 to C4 with signals supplied from outside directly, as the test command tCMD, the test address signal tADD, the test clock signal tCK, the test-chip select signal tCS, and the test-clock enable signal tCKE.
Incidentally, although explanations are made with an example of a case of using a crack check switch TSW (described later) in the first embodiment, it is also possible to configure such that test terminals of the semiconductor chips C1 to C4 as memory chips are connected to each other by a through silicon via TSV2 of the type shown in
Next, the semiconductor chip C1 as a memory chip included in the semiconductor device shown in
In
The semiconductor chip C1 has a configuration of a so-called “wide IODRAM”. As shown in
As shown in
In the first embodiment, the plurality of through silicon vias 15 provided on the semiconductor chip C1 include a plurality of through silicon vias as data terminals that transmit and receive data Data to and from outside of the semiconductor chip C1, a plurality of through silicon vias as normal control signal terminals that transmit and receive a command CMD, an address signal ADD, a clock signal CK, a chip select signal CS, and a clock enable signal CKE to and from outside of the semiconductor chip C1, a plurality of through silicon vias as power-supply terminals to which power-supply voltages VDD and VSS and the like are supplied, and a plurality of through silicon vias as test terminals that transmit and receive the test command tCMD, the test address signal tADD, the test clock signal tCK, the test-chip select signal tCS1-4, and the test-clock enable signal tCKE1-4, which are control signals for testing.
Among the through silicon vias mentioned above, the through silicon vias as data terminals and the through silicon vias as normal control signal terminals are provided for each of the channels 21A to 21D individually. Meanwhile, the through silicon vias as power-supply terminals and the through silicon vias as test terminals are provided commonly to the channels 21A to 21D. Furthermore, the semiconductor chip C1 includes a through silicon via as a check terminal DA (described later). It is possible to configure such that this through silicon via as the check terminal DA is formed not to be included in any one of the through silicon via groups 22A to 22D, or formed to be included in any one of the through silicon via groups 22A to 22D.
Various operations such as a read operation, a write operation, and a refresh operation can be controlled by a control circuit on the semiconductor chip C0 as a controller chip individually for each of the channels 21A to 21D shown in
In an area between the through silicon via groups 22A and 22D and between the through silicon via groups 22B and 22C, that is, in a central area of the through-silicon-via array area 22, a plurality of testing pads 17 are arranged linearly in an X direction (first direction) shown in
Next, a cross-sectional configuration of the semiconductor chip C1 is explained with reference to
As shown in
As shown in
Each of the wiring layers L0 to L3 having a multilayer wiring structure is configured such that the resistance on a wiring layer at the lower-layer side is equal to or higher than that on a wiring layer on the upper-layer side. In other words, the resistance value of each of the wiring layers L0 to L3 is set to be equal to or less than resistance values of one or more wiring layers at a farther side from the semiconductor substrate 31 than the corresponding layer. As an example, in the first embodiment, the wiring layer L0 on the lowermost layer is made of tungsten W, the wiring layers L1 to L3 are made of aluminum Al, and the thickness of the wiring layer L3 on the uppermost layer is made thicker than those of the wiring layers L1 and L2, so that the resistance of the wiring layer L3 becomes low. Accordingly, as for the resistance values of the wiring layers L0 to L3, a relationship of L0>L1≧L2>L3 is established. However, interrelationships among the resistance values of the respective layers having a multilayer wiring structure are not limited to that mentioned above.
The wiring layers L0 to L3 constitutes various wires such as a signal wire and a power-supply wire. Specifically, pads P0 to P3 connected to through-hole electrodes 1TH to 3TH shown in
As shown in
The substrate penetrating conductors 44 penetrate the semiconductor substrate 31 and the interlayer dielectric film 32 and are electrically connected to the wiring layer L0, and the rear-face bump electrodes 12 electrically connected to the substrate penetrating conductors 44 are exposed to the rear face (the other face) of the semiconductor substrate 31.
The surface bump electrodes 9 and the rear-face bump electrodes 12 function as terminals of the semiconductor chip C1.
Furthermore, the insulating ring 43 is formed in the semiconductor substrate 31 to surround each of the substrate penetrating conductors 44. The insulating ring 43 has a function of insulating each of the through silicon vias 15 from an area (a transistor area) in the semiconductor substrate 31 having various circuit elements formed thereon.
As shown in
Next, a planar configuration in the through-silicon-via array area 22 is explained in detail with reference to
As shown in
In the first embodiment, as shown in
To be specific, as shown in
As shown in
In other words, in each of the through silicon via groups 22A to 22D in each of the through-silicon-via array areas 22, the crack check wire 18 is arranged in the following manner. That is, the crack check wire 18 extends in the Y direction along one of the penetrating conductor arrays 2a. The crack check wire 18 is then bent towards the X direction at a position where it has passed by a through silicon via 15 at one end of the one penetrating conductor array 2a. The crack check wire 18 is bent again towards the Y direction at a position where it has passed by this through silicon via 15 and extends in a direction the reverse of the Y direction along the one penetrating conductor array 2a. The crack check wire 18 is then bent again towards the X direction at a position where it has passed by a through silicon via 15 at another end of the one penetrating conductor array 2a, and then passes by another penetrating conductor array 2a which is adjacent to the one penetrating conductor array 2a.
It is preferable that the crack check wire 18 is formed as a part of the wiring layer L0 on the lowermost layer shown in
The crack check wire 18 is configured to form a conductive path that passes through the through silicon via group 22A, the through silicon via group 22B, the through silicon via group 22C, and the through silicon via group 22D in this order and electrically connects the check terminal DA (first terminal) and the power-supply terminal VSS (second terminal) when the crack check switch TSW is in a conductive state. The crack check switch TSW is a switch which enters in a conductive state when the crack check enable signal TE at an active level is supplied. The crack check switch TSW may include a transistor inserted in the crack check wire 18, for example.
In the semiconductor chip C1 according to the first embodiment, whether cracks are generated in the through-silicon-via array area 22 can be detected by a method described below, for example. That is, as shown in
When a current flows into the check terminal DA, because the crack check wire 18 is in a conductive state, it can be determined that cracks are not generated around the crack check wire 18. With regard to the semiconductor chip C1 according to the first embodiment, because the crack check wire 18 is arranged to pass through adjacent penetrating conductor arrays 2a in all the through silicon via groups 22A to 22D in the through-silicon-via array area 22, it can be determined that cracks are not generated in the through-silicon-via array area 22.
On the other hand, when any current does not flow into the check terminal DA, it can be determined that a part of the crack check wire 18 is disconnected due to the presence of cracks around the crack check wire 18. Therefore, it can be determined that cracks are generated in the through-silicon-via array area 22.
As described above, with regard to the semiconductor chip C1 according to the first embodiment, whether cracks are generated in the through-silicon-via array area 22 can be detected based on a conduction state between the check terminal DA and the power-supply terminal VSS when a control signal (voltage potential difference) is supplied between the check terminal DA and the power-supply terminal VSS via the crack check wire 18.
In the first embodiment, as shown in
Turning to
In the semiconductor chip shown in
As shown in
The reference voltage Vref is a static signal and is input to each gate of the internal power-supply generation circuits 19A to 19D, and thus there is no electric charge consumption. Therefore, the reference-voltage generation circuit 29 that generates the reference voltage Vref has a small drive capability and an excessively large fan-out. Accordingly, the reference voltage Vref is considerably susceptible to the effect of noise from adjacent wires. Once the reference voltage Vref is superimposed by noise, the level of the reference voltage Vref fluctuates and it takes some time for the level to return to a normal level. Therefore, malfunctions may occur in the internal power-supply generation circuits 19A to 19D.
In the semiconductor chip shown in
The crack check wire 18A shown in
In the semiconductor chip shown in
Although explanations have been made with an example of a case where, in the semiconductor chip shown in
Turning to
In the first embodiment, forming the crack check wire 18 as a part of the wiring layer L0 on the lowermost layer is preferable in terms of that cracks generated on layers close to semiconductor substrates such as the interlayer dielectric films 32 and 33 and the wiring layer L0 shown in
However, depending to the behavior of generated cracks, forming the crack check wire 18 as a part of the wiring layer L0 on the lowermost layer may rather cause insufficient accuracy of detecting cracks. Such cracks are, for example, cracks generated only on a wiring layer on an upper-layer of a semiconductor chip and not reaching the lowermost layer of the wiring layer. More specific examples of such cracks include cracks generated around a solder-bonded part formed by solder-bonding the surface bump electrodes 9 of the semiconductor chip C1 and the rear-face bump electrodes of the semiconductor chip C2. Since this kind of cracks are formed away from the crack check wire 18, even if the cracks are generated, the disconnection of the crack check wire 18 may not occur. In that case, it is impossible to detect the crack using the crack check wire 18.
Meanwhile, forming the crack check wire 18 as a part of the wiring layer L3 on the uppermost layer in order to detect cracks generated on an upper-layer of a wiring layer of a semiconductor chip with high accuracy may cause that the accuracy of detecting cracks generated on a layer closer to a semiconductor substrate is not sufficient.
That is, in either case of forming the crack check wire 18 as a part of the wiring layer L3 on the uppermost layer or of the wiring layer L0 on the lowermost layer, there is a possibility that cracks cannot be detected with high accuracy.
On the other hand, according to the second embodiment, as shown in
That is, in the crack check wire 18B shown in
In the second embodiment, the first crack check wire 18C (shown by a solid line in
Furthermore, in the crack check wire 18B shown in
In the second embodiment, similarly to the first embodiment described above, the crack check wire 18B is configured to form a conductive path that passes through the through silicon via group 22A, the through silicon via group 22B, the through silicon via group 22C, and the through silicon via group 22D in this order and electrically connects the check terminal DA (first terminal) and the power-supply terminal VSS (second terminal) when the crack check switch TSW is in a conductive state.
Furthermore, similarly to the first embodiment described above, with regard to the semiconductor chip according to the second embodiment, whether cracks are generated in the through-silicon-via array area 22 can be detected based on a conduction state between the check terminal DA and the power-supply terminal VSS when a control signal (voltage potential difference) is supplied between the check terminal DA and the power-supply terminal VSS via the crack check wire 18B.
In the second embodiment, because the crack check wire 18B is configured to include the first crack check wire 18C that is formed on one wiring layer selected from a plurality of wiring layers, the second crack check wire 18D that is formed on a wiring layer different from the wiring layer on which the first crack check wire 18C is formed, and the contact electrode 18E that electrically connects the first crack check wire 18C and the second crack check wire 18D, cracks can be detected simultaneously on two wiring layers, which are a wiring layer on which the first crack check wire 18C is formed and a wiring layer on which the second crack check wire 18D is formed. As compared to a case where a crack check wire is formed on any one of the wiring layer L3 on the uppermost layer or the wiring layer L0 on the lowermost layer, in the second embodiment, the distance between cracks and the crack check wire 18B is closer regardless of where the cracks are generated, and therefore detection of cracks can be made with high accuracy.
In the second embodiment, the first crack check wire 18C is formed on the wiring layer L0 on the lowermost layer and the second crack check wire 18D is formed on the wiring layer L3 on the uppermost layer. Therefore, both cracks generated around the through silicon via 15 and cracks generated only on a wiring layer on an upper-layer of a semiconductor chip, such as cracks around the aforementioned solder-bonded part can be detected with high accuracy.
In the second embodiment, although explanations have been made with an example of a case where the first crack check wire 18C is formed on the wiring layer L0 on the lowermost layer and the second crack check wire 18D is formed on the wiring layer L3 on the uppermost layer, wiring layers on which the first crack check wire 18C and the second crack check wire 18D are formed can be any wiring layers as far as these crack check wires are formed on a different layer.
Turning to
Similarly to the crack check wire 18B shown in
However, the crack check wire 18F shown in
More specifically, in the crack check wire 18F shown in
Furthermore, similarly to the crack check wire 18B shown in
Furthermore, the extending length of the second crack check wire 18H which is formed on the wiring layer L3 on the uppermost layer is shorter than that of crack check wire 18B shown in
In the crack check wire 18F shown in
Furthermore, cracks generated on a semiconductor chip often have a size larger than a gap between adjacent through silicon vias 15, which is normally approximately 50 μm. Therefore, in the crack check wire 18F shown in
Next, a modification of the first and second embodiments of the present invention is explained. In
Because the semiconductor chip C4 is a semiconductor chip on the uppermost part of the semiconductor device 1, it suffices that the semiconductor chip C4 can take in signals and power supplied from the rear-face bump electrodes 12 on the semiconductor chip C3 via the surface bump electrodes 9 on the semiconductor chip C4, and it is not necessary to supply the signals supplied from the rear-face bump electrodes 12 on the semiconductor chip C3 to other semiconductor chips.
As described above, when the substrate penetrating conductors 44 and the rear-face bump electrodes 12 are not formed on the semiconductor chip C4, it is not necessary to have the semiconductor chip C4 made thin so as to facilitate the formation of the substrate penetrating conductors 44 and the rear-face bump electrodes 12, and thus the semiconductor chip C4 can be thicker than the semiconductor chips C1 to C3. As a result, it is possible to suppress deformation of chips due to thermal stress at the time of manufacturing the semiconductor device 1, specifically, at the time of stacking the semiconductor chips C1 to C4.
In
While not specifically claimed in the claim section, the applicant reserves the right to include in the claim section of the application at any appropriate time the following semiconductor chip and semiconductor devices:
A1. A semiconductor chip comprising:
a substrate;
a plurality of penetration electrodes penetrating the substrate, the penetration electrodes including first and second penetration electrodes provided in adjacent to each other;
a crack check wire connected between a first terminal and a second terminal, the crack check wire being arranged between the first and second penetration electrodes; and
a plurality of wiring layers including first and second wiring layers, wherein
the crack check wire includes:
the first crack check wire and the second crack check wire are arranged in respectively different positions,
the penetration electrodes are arranged in a predetermined direction between the first crack check wire and the second crack check wire such that a penetration electrodes array is formed, and
the contact electrode is arranged on an outer side with respect to the penetration electrodes array.
A2. A semiconductor device comprising a plurality of semiconductor chips, at least one of the semiconductor chips includes:
a substrate;
a plurality of penetration electrodes penetrating the substrate, the penetration electrodes including first and second penetration electrodes provided in adjacent to each other; and
a crack check wire connected between a first terminal and a second terminal, the crack check wire being arranged between the first and second penetration electrodes.
A3. A semiconductor device comprising:
an array area including a plurality of penetration electrodes; and
a crack check wire connected between a first terminal and a second terminal in response to a control signal,
wherein at least a part of the crack check wire is arranged in the array area.
A4. The semiconductor device as A3, further comprising a multilayer wiring structure that is formed in the array area, wherein
the multilayer wiring structure includes a first wiring layer and a second wiring layer that is formed on an upper-layer side of the first wiring layer, and
at least a part of the crack check wire includes a first part formed as the first wiring layer and a second part formed as the second wiring layer.
A5. The semiconductor device as A3, further comprising:
a first channel region including a first channel and a second channel each of which includes a storage area and a control circuit that controls an access to the storage area, the first and second channels being arranged in a first direction; and
a second channel region including a third channel and a fourth channel each of which includes a storage area and a control circuit that controls an access to the storage area, the third and fourth channels being arranged in the first direction, wherein
the first and second channel regions are arranged in a second direction that intersects with the first direction, and
the array area is arranged between the first channel region and the second channel region.
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