Semiconductor device
11227915 · 2022-01-18
Assignee
Inventors
- Ryuta Tezuka (Yokohama Kanagawa, JP)
- Mitsuhiro Noguchi (Yokohama Kanagawa, JP)
- Tomoaki Shino (Kamakura Kanagawa, JP)
Cpc classification
H01L2224/48147
ELECTRICITY
H01L25/18
ELECTRICITY
H01L2924/00014
ELECTRICITY
H01L2224/05186
ELECTRICITY
H01L29/0684
ELECTRICITY
H01L2224/05186
ELECTRICITY
H01L2924/00014
ELECTRICITY
H01L2224/04042
ELECTRICITY
H01L2224/06135
ELECTRICITY
H01L2224/48463
ELECTRICITY
H01L2224/05686
ELECTRICITY
H01L2224/05686
ELECTRICITY
International classification
H01L29/06
ELECTRICITY
Abstract
According to one embodiment, a semiconductor device includes a first semiconductor layer on a semiconductor substrate and a second semiconductor layer on the first semiconductor layer. The first semiconductor layer is between the second semiconductor layer and the semiconductor substrate in a first direction. A first conductive layer is on the second semiconductor layer and contacting the second semiconductor layer. A third semiconductor layer is spaced from the second semiconductor layer in a second direction and connected to the first semiconductor layer. A second conductive layer is spaced from the first conductive layer in the second direction and connected to the third semiconductor layer. Each of the first semiconductor layer, the second semiconductor layer, and the third semiconductor layer extends lengthwise in a third direction intersecting the first direction and the second direction.
Claims
1. A semiconductor device, comprising: a first semiconductor layer on a semiconductor substrate; a second semiconductor layer on the first semiconductor layer, the first semiconductor layer being between the second semiconductor layer and the semiconductor substrate in a first direction; a first conductive layer on the second semiconductor layer and contacting the second semiconductor layer; a third semiconductor layer spaced from the second semiconductor layer in a second direction intersecting the first direction and connected to the first semiconductor layer; and a second conductive layer spaced from the first conductive layer in the second direction and connected to the third semiconductor layer, wherein each of the first semiconductor layer, the second semiconductor layer, and the third semiconductor layer extends lengthwise in a third direction intersecting the first direction and the second direction.
2. The semiconductor device according to claim 1, further comprising: a fourth semiconductor layer spaced from the third semiconductor layer in the second direction, the third semiconductor layer being between the second and fourth semiconductor layers in the second direction; and a third conductive layer spaced from the second conductive layer in the second direction and connected to the fourth semiconductor layer, the second conductive layer being between the first and third conductive layers, wherein the fourth semiconductor layer extends lengthwise in the third direction.
3. The semiconductor device according to claim 1, further comprising: a fifth semiconductor layer connected to an end of the third semiconductor layer in the third direction, the fifth semiconductor layer extending lengthwise in the second direction; and a fourth conductive layer connected to an end of the second conductive layer in the third direction and extending lengthwise in the second direction.
4. The semiconductor device according to claim 1, further comprising: a bonding pad, wherein each of the first semiconductor layer, the second semiconductor layer, and the third semiconductor layer includes a first part overlapped by the bonding pad, when viewed from the first direction, and a second part not overlapped by the bonding pad, when viewed from the first direction.
5. The semiconductor device according to claim 4, further comprising: a plurality of first contact electrodes connected to the first conductive layer or the second conductive layer, wherein the first contact electrodes are at positions not overlapped by the bonding pad when viewed from the first direction.
6. The semiconductor device according to claim 1, further comprising: an N-well containing an N-type impurity in the semiconductor substrate in a region below the first semiconductor layer in the first direction.
7. The semiconductor device according to claim 6, further comprising: a bonding pad; and a second contact electrode connected to the N well, wherein the second contact electrode is at a position overlapped by the bonding pad when viewed from the first direction.
8. The semiconductor device according to claim 7, further comprising: a bonding wire attached to a circular portion of the bonding pad.
9. A semiconductor device, comprising: a semiconductor substrate including a plurality of shallow trench isolation (STI) features extending into the semiconductor substrate in a first direction and spaced from each other in a second direction, the STI features each extending lengthwise in a third direction orthogonal to the first and second directions and dividing the semiconductor substrate into a plurality of first regions of a first conductivity type; a first insulation film on an upper surface of each first region, each first insulation film being between an adjacent pair of shallow trench insulation features in the second direction; a first semiconductor layer on an upper surface of each first insulation film, each first semiconductor layer being between the adjacent pair of shallow trench insulation features in the second direction; a second insulation film on an upper surface of each first semiconductor layer and an upper surface of the adjacent pair of shallow trench insulation features, the second insulation film including an opening exposing a portion of the upper surface of the first semiconductor layer; a second semiconductor layer on the second insulation film, the second insulation film being between the second semiconductor layer and the first semiconductor layer in the first direction; a first conductive layer on the second semiconductor layer and contacting the second semiconductor layer; a third semiconductor layer spaced from the second semiconductor layer in the second direction and contacting the first semiconductor layer via the opening in the second insulation film; and a second conductive layer spaced from the first conductive layer in the second direction and contacting the third semiconductor layer, wherein each of the first semiconductor layer, the second semiconductor layer, and the third semiconductor layer extends lengthwise in the third direction.
10. The semiconductor device according to claim 9, further comprising: a fourth semiconductor layer spaced from the third semiconductor layer in the second direction, the third semiconductor layer being between the second and fourth semiconductor layers in the second direction, the second insulating film being between the fourth semiconductor layer and the first semiconductor layer in the first direction; and a third conductive layer spaced from the second conductive layer in the second direction and contacting the fourth semiconductor layer, the second conductive layer being between first and third conductive layers in the second direction, wherein the fourth semiconductor layer extends lengthwise in the third direction.
11. The semiconductor device according to claim 9, further comprising: a fifth semiconductor layer connected to an end of the third semiconductor layer in the third direction, the fifth semiconductor layer extending lengthwise in the second direction; and a fourth conductive layer connected to an end of the second conductive layer in the third direction and extending lengthwise in the second direction.
12. The semiconductor device according to claim 9, further comprising: a bonding pad, wherein each of the first semiconductor layer, the second semiconductor layer, and the third semiconductor layer includes a first part overlapped by the bonding pad, when viewed from the first direction, and a second part not overlapped by the bonding pad, when viewed from the first direction.
13. The semiconductor device according to claim 12, further comprising: a bonding wire attached to a circular portion of the bonding pad.
14. The semiconductor device according to claim 12, further comprising: a plurality of first contact electrodes connected to the first conductive layer or the second conductive layer, wherein the first contact electrodes are at positions not overlapped by the bonding pad, when viewed from the first direction.
15. The semiconductor device according to claim 9, wherein the plurality of first regions is in a well of the first conductivity type, the well extending below and between the STI features to connect the plurality of first regions.
16. The semiconductor device according to claim 15, further comprising: a bonding pad; and a second contact electrode connected to the well.
17. The semiconductor device according to claim 16, wherein the second contact electrode is at a position overlapped by the bonding pad when viewed from the first direction.
18. A semiconductor device including a plurality of decoupling capacitors, the semiconductor device comprising: a bonding pad on a semiconductor substrate; a first semiconductor layer on the semiconductor substrate and including a first portion below the bonding pad in a first direction and a second portion not below the bonding pad in the first direction; a second semiconductor layer on the first portion of the first semiconductor layer, the first semiconductor layer being between the second semiconductor layer and the semiconductor substrate in the first direction; a first conductive layer on the second semiconductor layer and contacting the second semiconductor layer; a third semiconductor layer spaced from the second semiconductor layer in a second direction intersecting the first direction and connected to the first semiconductor layer, the third semiconductor layer including a first portion below the bonding pad and a second portion not below the bonding pad; and a second conductive layer spaced from the first conductive layer in the second direction and connected to the third semiconductor layer, wherein each of the first semiconductor layer, the second semiconductor layer, and the third semiconductor layer extends lengthwise in a third direction intersecting the first direction and the second direction beyond an outer edge of the bonding pad.
19. The semiconductor device according to claim 18, further comprising: a fourth semiconductor layer spaced from the third semiconductor layer in the second direction, the third semiconductor layer being between the second and fourth semiconductor layers in the second direction; and a third conductive layer spaced from the second conductive layer in the second direction and connected to the fourth semiconductor layer, the second conductive layer being between the first and third conductive layers, wherein the fourth semiconductor layer extends lengthwise in the third direction beyond the outer edge of the bonding pad.
20. The semiconductor device according to claim 18, further comprising: a fifth semiconductor layer connected to an end of the third semiconductor layer in the third direction, the fifth semiconductor layer extending lengthwise in the second direction; and a fourth conductive layer connected to an end of the second conductive layer in the third direction and extending lengthwise in the second direction, wherein the fifth semiconductor layer and the fourth conductive layer are not below the bonding pad.
Description
DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
(32) Embodiments provide a semiconductor device that operates at a high speed.
(33) In general, according to one embodiment, a semiconductor device includes a first semiconductor layer on a semiconductor substrate and a second semiconductor layer on the first semiconductor layer. The first semiconductor layer is between the second semiconductor layer and the semiconductor substrate in a first direction. A first conductive layer is on the second semiconductor layer and contacting the second semiconductor layer. A third semiconductor layer is spaced from the second semiconductor layer in a second direction and connected to the first semiconductor layer. A second conductive layer is spaced from the first conductive layer in the second direction intersecting the first direction. The second conductive layer is connected to the third semiconductor layer. Each of the first semiconductor layer, the second semiconductor layer, and the third semiconductor layer extends lengthwise in a third direction intersecting the first direction and the second direction.
(34) Next, a semiconductor device according to various example embodiments will be described with reference to drawings. The following embodiments are merely examples, and are not intended to limit the disclosure.
(35) In the specification, one direction parallel to a surface of a semiconductor substrate is referred to as an X direction, another direction parallel to the surface of the semiconductor substrate and perpendicular to the X direction is referred to as a Y direction, and a direction orthogonal to the surface of the semiconductor substrate is referred to as a Z direction.
(36) In the specification, a direction along a particular plane may be referred to as a first direction, a direction intersecting the first direction along the plane may be referred to as a second direction, and a direction intersecting the plane may be referred to as a third direction. Anyone of the first direction, the second direction, and the third direction may or may not correspond to any one of the X direction, the Y direction, and the Z direction.
(37) In the specification, expressions such as “upper” and “lower” are generally taking the semiconductor substrate as a reference. For example, a direction going further away from the semiconductor substrate along the Z direction is referred to as an upward or upper direction, and a direction approaching the semiconductor substrate along the Z direction is referred to as lower or lower direction. When referring to a lower surface or a lower end part of an element, component, or other structural aspect, it means a surface or an end part on a semiconductor substrate side of the element, component, or other structural aspect, and when referring to an upper surface or an upper end part, it means a surface or an end part on a side opposite to the semiconductor substrate. A surface intersecting the plane of X direction and the Y direction is referred to as a side surface or the like.
(38) In the present specification, when a first element is referred to as being “electrically connected” to a second element, the first element may be directly connected to the second element, or the first element may be connected to the second element via a wiring, a semiconductor member, a transistor or the like. For example, when three transistors are connected in series, a first transistor in the series may still be referred to as “electrically connected” to a third transistor in the series even when a second transistor in the series is in an OFF state.
(39) In the present specification, when the first element is said to be “connected between” the second element and the third element, it may mean that the first element, the second element, and the third element are connected in series, and the first element is provided in a current path between the second element and the third element.
(40) In the present specification, when a circuit is said to “electrically conduct” between two wirings, it may mean for example, that the circuit includes a transistor, the transistor is provided in a current path between the two wirings, and the transistor is in an ON state.
(41) Furthermore, in the present specification, in some instances, portions of the same initial layer which get divided into separate portions, may each be referred to as a layer or a portion thereof depending on context.
First Embodiment
(42)
(43) As shown in
(44) As shown in
(45)
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(47) Some of the bonding pad electrodes P are connected to input and output signal lines W.sub.IO0, W.sub.IO1 W.sub.IO2 W.sub.IO3 . . . that transfer input signals and output signals. The plurality of input and output signal lines W.sub.Io0, W.sub.IO1, W.sub.IO2, W.sub.IO3 . . . are connected to a comparator or the like in the internal circuit IC.
(48) Some of the bonding pad electrodes P are connected to a voltage transfer line W.sub.VSS that supplies a ground voltage VSS to each element in the memory die MD. The voltage transfer line W.sub.VSS is connected to the internal circuit IC. A pull-down circuit PD is connected between the voltage transfer line W.sub.vss and each of the input and output signal lines W.sub.IO0, W.sub.IO1, W.sub.IO2, W.sub.IO3 . . . . Each pull-down circuit PD includes a plurality of NMOS transistors connected in parallel with each other between the voltage transfer line W.sub.VSS and each of the input and output signal lines W.sub.IO0, W.sub.IO1, W.sub.IO2, W.sub.IO3 . . . .
(49) Some of the bonding pad electrodes P are connected to a voltage transfer line W.sub.VCCQ that supplies a drive voltage VCCQ to each element in the memory die MD. The voltage transfer line W.sub.VCCQ is connected to the internal circuit IC. A pull-up circuit PU is connected between the voltage transfer line W.sub.VCCQ and each of the input and output signal lines W.sub.IO0, W.sub.IO1, W.sub.IO2, W.sub.IO3 . . . . Each pull-up circuit PU includes a plurality of PMOS transistors connected in parallel with each other between the voltage transfer line W.sub.VCCQ and each of the input and output signal lines W.sub.IO0, W.sub.IO1, W.sub.IO2, W.sub.IO3 . . . .
(50) The plurality of decoupling capacitors C.sub.D are connected in parallel with each other between the voltage transfer line W.sub.VSS and the voltage transfer line W.sub.VCCQ.
(51) The internal circuit IC includes the memory cell arrays MCA and the peripheral circuit PC (described with reference to
(52) Next, a configuration example of the memory die MD will be described with reference to
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(54) As shown in
(55)
(56)
(57) A substantially circular insulating region RI and a substantially rectangular conductive region RC surrounding the substantially circular insulating region RI are provided in a region in the wiring layer MX overlapping the bonding pad electrode P when viewed from the Z direction. The insulating region RI is, for example, a region embedded with an insulating layer 51 such as silicon oxide (SiO.sub.2) and does not include a conductive member or the like. The bonding region BB corresponding to a contact surface of the bonding pad electrode P and the bonding wire B is provided inside the insulating region RI. The conductive region RC includes, for example, a plurality of conductive members 52 extending in the X direction and arranged in the Y direction, and a plurality of conductive members 53 extending in the Y direction and arranged in the X direction. The conductive members 52 and 53 are a part of the plurality of wirings mX described above. An insulating layer 54 such as silicon oxide (SiO.sub.2) is provided between the conductive members 52 and 53.
(58) Six wiring groups WG arranged in the X direction and the Y direction are provided in a region in the wiring layer MX not overlapping the bonding pad electrode P when viewed from the Z direction. Each of the six wiring groups WG includes a plurality of wirings mX extending in the X direction and arranged in the Y direction. Each of the plurality of wirings mX functions as apart of the voltage transfer line W.sub.VSS or the voltage transfer line W.sub.VCCQ described above. A wiring mX is provided around the six wiring groups WG such that the wiring mX surrounds the six pairs of wiring groups WG and the conductive members 52 and 53. The wiring mX functions as a part of the voltage transfer line W.sub.VSS.
(59) Although detailed configuration is omitted, the wiring layer M0 (see
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(62) An impurity region S.sub.N is provided in a region corresponding to the decoupling capacitor C.sub.D in the semiconductor substrate region SS. The impurity region S.sub.N contains, for example, an N-type impurity such as phosphorus (P) or arsenic (As). An impurity region S.sub.N+ is provided at one end of the impurity region S.sub.N in the Y direction. The impurity region S.sub.N+ contains, for example, an N-type impurity such as phosphorus (P) or arsenic (As). An impurity concentration in the impurity region S.sub.N+ is higher than an impurity concentration in the impurity region S.sub.N.
(63) The P-well region S.sub.PW contains, for example, a P-type impurity such as boron (B). An impurity concentration in the P-well region S.sub.PW is higher than an impurity concentration in the semiconductor substrate region S.sub.S. An impurity region S.sub.P+ is provided in a region corresponding to the plurality of contact electrodes CS.sub.VSS in the P-well region S.sub.PW. The impurity region S.sub.P+ includes, for example, a P-type impurity such as boron (B). An impurity concentration in the impurity region S.sub.P+ is higher than the impurity concentration in the P-well region S.sub.PW.
(64)
(65) As shown in
(66) The insulating layer 101 contains, for example, silicon oxide (SiO.sub.2).
(67) The semiconductor layer 102 contains polycrystalline silicon containing an N-type impurity such as phosphorus (P) or arsenic (As), or a P-type impurity such as boron (B). As shown in
(68) As shown in
(69) The insulating layer 103 contains, for example, silicon oxide (SiO.sub.2). As shown in
(70) The semiconductor layer 104 (
(71) As shown in
(72) As shown in
(73) As shown in
(74) As shown in
(75) The conductive layer 105 (
(76) The conductive layer 105a has a longitudinal dimension in the Y direction. A lower surface of the conductive layer 105a is connected to an upper surface of the semiconductor layer 104a. As shown in
(77) The conductive layer 105b has a longitudinal dimension in the Y direction. A lower surface of the conductive layer 105b is connected to an upper surface of the semiconductor layer 104b. As shown in
(78) The conductive layer 105c has a longitudinal dimension in the Y direction. A lower surface of the conductive layer 105c is connected to an upper surface of the semiconductor layer 104c. As shown in
(79) The conductive layer 105d has a longitudinal dimension in the X direction. A lower surface of the conductive layer 105d is connected to an upper surface of the semiconductor layer 104d.
(80) The contact electrodes CS.sub.VSS are electrically connected to the bonding pad electrodes P to which the ground voltage VSS is supplied. The contact electrodes CS.sub.VSS are via contact electrodes extending in the Z direction, and contains, for example, titanium nitride (TiN) and tungsten (W). A plurality of contact electrodes CS.sub.VSS exemplified in
(81) The contact electrodes CS.sub.VCCQ are electrically connected to the bonding pad electrodes P to which the drive voltage VCCQ is supplied. The contact electrodes CS.sub.VCCQ are via contact electrodes extending in the Z direction, and contains, for example, titanium nitride (TiN) and tungsten (W).
(82) Some contact electrodes CS.sub.VCCQ in
(83) As shown in more clearly in
Comparative Example
(84) Next, a memory die according to a comparative example will be described with reference to
(85) Unlike the memory die according to the first embodiment, the memory die according to the comparative example does not include the decoupling capacitors C.sub.D. Instead, the memory die according to the comparative example includes decoupling capacitors C.sub.D′.
(86) As shown in
(87) The insulating layer 103′ (
(88) A semiconductor layer 104′ (
(89) The conductive layer 105′ contains tungsten silicide (WSi) or the like. The conductive layer 105′ includes a conductive layer 105a′ and a conductive layer 105d′ that are two parts arranged in the Y direction. A lower surface of the conductive layer 105a′ is connected to an upper surface of the semiconductor layer 104a′. A lower surface of the conductive layer 105d′ is connected to the upper surface of the semiconductor layer 104a′.
(90) A plurality of contact electrodes CS.sub.VSS exemplified in
(91) Effect
(92) When the bonding wires B (see
(93) Here, the plurality of contact electrodes CS.sub.VSS and CS.sub.VCCQ connected to the decoupling capacitors C.sub.D′ are connected to the wirings mX in the wiring groups WG (described with reference to
(94) A resistivity of the semiconductor layer 102 is higher than a resistivity of the conductive layer 105′ (
(95) As described with reference to
(96) According to such a configuration, the entire semiconductor layer 102 can be brought close to the conductive layer 105d via the conductive layer 105c. Accordingly, charging and discharging of the semiconductor layer 102 can be accelerated still without disposing the contact electrodes CS.sub.VSS or the like in the bonding region BB (see
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(98) When the signal frequency is relatively low, the capacitance value of the decoupling capacitor C.sub.D′ is larger than the capacitance value of the decoupling capacitor C.sub.D. A possible reason for the relationship is considered to be that in the decoupling capacitor C.sub.D, charges are not accumulated since the semiconductor layer 104 does not face the semiconductor layer 102c (
(99) When the signal frequency is relatively high, the capacitance value of the decoupling capacitor C.sub.D is larger than the capacitance value of the decoupling capacitor C.sub.D′. One possible reason for the relationship is considered to be that in the decoupling capacitor C.sub.D′, a partial region of the semiconductor layer 102 is far from the conductive layer 105d′, and the charging and discharging speed in such a part is low. Another possible reason for the relationship is considered to be that in the decoupling capacitor C.sub.D, the entire semiconductor layer 102 is provided in the vicinity of the conductive layer 105d, and charging and discharging are performed at a high speed in the regions 102a and 102b of the semiconductor layer 102.
Second Embodiment
(100) Next, a memory die according to a second embodiment will be described with reference to
(101) The memory die according to the second embodiment is similar to the memory die MD according to the first embodiment. However, instead of including the decoupling capacitors C.sub.D, the memory die according to the second embodiment includes decoupling capacitors C.sub.D2. Each decoupling capacitor C.sub.D2 is similar to the decoupling capacitor C.sub.D according to the first embodiment. However, instead of including the insulating layer 103, the semiconductor layer 104, and the conductive layer 105, the decoupling capacitor C.sub.D2 include an insulating layer 203, a semiconductor layer 204, and a conductive layer 205.
(102) The insulating layer 203 is similar to the insulating layer 103. However, the insulating layer 203 does not have the opening OP.sub.103 (
(103) The semiconductor layer 204 is similar to the semiconductor layer 104. However, the semiconductor layer 204 only includes a semiconductor layer 204a corresponding to the semiconductor layer 104a, a semiconductor layer 204c corresponding to the semiconductor layer 104c, and a semiconductor layer 204d corresponding to the semiconductor layer 104d, and does not include a semiconductor layer 204b corresponding to the semiconductor layer 104b. The semiconductor layer 204c is connected to an upper surface of a part of the semiconductor layer 102 not covered by the insulating layer 203.
(104) The conductive layer 205 is similar to the conductive layer 105. However, the conductive layer 205 only includes a conductive layer 205a corresponding to the conductive layer 105a, a conductive layer 205c corresponding to the conductive layer 105c, and a conductive layer 205d corresponding to the conductive layer 105d, and does not include a conductive layer 205b corresponding to the conductive layer 105b.
(105) As shown in
Third Embodiment
(106) Next, a memory die according to a third embodiment will be described with reference to
(107) The memory die according to the third embodiment is configured similarly to the memory die according to the second embodiment. However, instead of including the decoupling capacitors C.sub.D2, the memory die according to the third embodiment includes decoupling capacitors C.sub.D3. Each decoupling capacitor C.sub.D3 is configured similarly to the decoupling capacitor C.sub.D2 according to the second embodiment. However, instead of including the semiconductor layer 204 and the conductive layer 205, the decoupling capacitor C.sub.D3 include a semiconductor layer (not separately depicted) and a conductive layer 305.
(108) The semiconductor layer of this third embodiment is configured similarly to the semiconductor layer 204. That is, the semiconductor layer includes a semiconductor layer corresponding to the semiconductor layer 204a, a semiconductor layer corresponding to the semiconductor layer 204c, and a semiconductor layer corresponding to the semiconductor layer 204d. However, in this embodiment, the part corresponding to the semiconductor layer 204c does not cover an end part on one side in the Y direction of the impurity region S.sub.N. Therefore, in the third embodiment, the corner part S.sub.NE (
(109) The conductive layer 305 is similar to the conductive layer 205. That is, the conductive layer 305 includes a conductive layer 305a corresponding to the conductive layer 205a, a conductive layer 305c corresponding to the conductive layer 205c, and a conductive layer 305d corresponding to the conductive layer 205d. However, the conductive layer 305c does not cover one end part in the Y direction of the impurity region S.sub.N. Therefore, in the third embodiment, as shown in
(110) Electric field concentration may occur in the corner part S.sub.NE of the impurity region S.sub.N. In such a case, if the corner part S.sub.NE of the impurity region S.sub.N is covered with a conductive layer or the like, dielectric breakdown is likely to occur in the vicinity of the corner part, and a life of the decoupling capacitor may be shortened. Therefore, in the first embodiment, the semiconductor layer 104 and the conductive layer 105 are arranged in a manner of not overlapping the corner part S.sub.NE of the impurity region S.sub.N. Similarly, in the third embodiment, the semiconductor layer and the conductive layer 305 are arranged in such a manner so as to not overlap the corner part S.sub.NE of the impurity region S.sub.N. According to such a configuration, a memory die having a long life compared with the second embodiment can be provided.
(111) In a comparative example shown in
Fourth Embodiment
(112) Next, a memory die according to a fourth embodiment will be described with reference to
(113) The memory die according to the fourth embodiment is configured similarly to the memory die according to the first embodiment. However, instead of including the decoupling capacitors C.sub.D, the memory die according to the fourth embodiment includes decoupling capacitors C.sub.D4. Each decoupling capacitor C.sub.D4 is configured similarly as the decoupling capacitor C.sub.D according to the first embodiment. However, instead of including the semiconductor layer 104 and the conductive layer 105, the decoupling capacitor C.sub.D4 include a conductive layer 405 and a semiconductor layer.
(114) The conductive layer 405 is configured similarly as the conductive layer 105. That is, the conductive layer 405 includes a conductive layer 405a corresponding to the conductive layer 105a, a conductive layer 405b corresponding to the conductive layer 105b, a conductive layer 405c corresponding to the conductive layer 105c, and a conductive layer 405d corresponding to the conductive layer 105d. However, the conductive layer 405d does not extend in the X direction.
(115) The semiconductor layer provided between the insulating layer 103 and the conductive layer 405 is configured similarly to the semiconductor layer 104. However, a planar shape of the semiconductor layer is formed in the same manner as the conductive layer 405.
Fifth Embodiment
(116) Next, a memory die according to a fifth embodiment will be described with reference to
(117) The memory die according to the fifth embodiment is configured similarly to the memory die according to the first embodiment. However, instead of including the semiconductor substrate S, the memory die according to the fifth embodiment includes a semiconductor substrate S.sub.5. The semiconductor substrate S.sub.5 is basically configured similarly to the semiconductor substrate S according to the first embodiment. However, as described with reference to
(118) Each decoupling capacitor C.sub.D5 according to the fifth embodiment is configured similarly to the decoupling capacitor C.sub.D according to the first embodiment. However, as shown in
(119)
(120) When the signal frequency is relatively low, the capacitance values of the decoupling capacitors C.sub.D5 and C.sub.D′ are approximately the same. On the other hand, when the signal frequency is relatively high, the capacitance value of the decoupling capacitor C.sub.D5 is larger than the capacitance value of the decoupling capacitor C.sub.D′. A reason for this relationship is resistivity of an upper surface of the semiconductor substrate S.sub.5 is reduced by the N-well region S.sub.NW.
(121) As described above, according to the fifth embodiment, the resistivity of the upper surface of the semiconductor substrate S.sub.5 is reduced by the N-well region S.sub.NW, and the capacitance value attenuation accompanying the increase of the signal frequency can be further suitably prevented.
(122) According to the fifth embodiment, a parasitic capacitance is generated by a depletion layer between the N-well region S.sub.NW of the semiconductor substrate S.sub.5 and the semiconductor substrate region S.sub.S provided below the N-well region S.sub.NW. Therefore, the capacitance value of the decoupling capacitor C.sub.D5 can be increased by the parasitic capacitance.
Sixth Embodiment
(123) Next, a memory die according to a sixth embodiment will be described with reference to
(124) The memory die according to the sixth embodiment is configured similarly to the memory die according to the fifth embodiment. However, instead of including the semiconductor substrate S.sub.5 and the decoupling capacitors C.sub.D5, the memory die according to the sixth embodiment includes a semiconductor substrate S.sub.6 and decoupling capacitors C.sub.D6.
(125) Each decoupling capacitor C.sub.D6 is basically configured similarly to the decoupling capacitor C.sub.D5 according to the fifth embodiment. However, the decoupling capacitor C.sub.D6 includes a plurality of through via holes OP.sub.CD by which the upper surface of the semiconductor substrate S.sub.6 is exposed. That is, the decoupling capacitor C.sub.D6 includes an insulating layer 601 instead of the insulating layer 101, as shown in
(126) The semiconductor substrate S.sub.6 is basically configured similarly to the semiconductor substrate S.sub.5 according to the fifth embodiment. However, for example, as shown in
(127) While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.