This application is based upon and claims the benefit of Japanese Patent Application No. 2021-030397, filed on Feb. 26, 2021, the entire contents of which are incorporated herein by reference.
Embodiments herein relate to a semiconductor device and a method of manufacturing the same.
There is known technology for forming a plurality of bonding electrodes on two wafers, bonding these two wafers via these plurality of bonding electrodes, and dicing these two wafers by the likes of a dicing blade, thereby forming a plurality of dies.
A semiconductor device according to an embodiment comprises a first chip and a second chip bonded via a plurality of bonding electrodes. The first chip comprises: a first substrate; a first semiconductor element; and a first bonding electrode which is one of the plurality of bonding electrodes and is electrically connected to the first semiconductor element. The second chip comprises: a second substrate; a second semiconductor element; and a second bonding electrode which is one of the plurality of bonding electrodes and is electrically connected to the second semiconductor element. The second substrate comprises: a pair of first regions which are provided in both end portions in a first direction and extend in a second direction intersecting with the first direction; and a pair of second regions which are provided in both end portions in the second direction and extend in the first direction. Viewed from a third direction intersecting with a surface of the second substrate, portions provided in the first region and the second region of the second substrate do not overlap the first substrate.
A semiconductor device according to an embodiment comprises a first chip and a second chip bonded via a plurality of bonding electrodes. The first chip comprises: a first substrate; a first semiconductor element; and a first bonding electrode which is one of the plurality of bonding electrodes and is electrically connected to the first semiconductor element. The second chip comprises: a second substrate; a second semiconductor element; and a second bonding electrode which is one of the plurality of bonding electrodes and is electrically connected to the second semiconductor element. When a roughness of at least one end portion in at least one of a first direction and a second direction intersecting with the first direction, of the first substrate is assumed to be a first roughness, and a roughness of at least one end portion in at least one of the first direction and the second direction of the second substrate is assumed to be a second roughness, the first roughness is smaller than the second roughness.
In a method of manufacturing a semiconductor device according to an embodiment, a first wafer comprising a first substrate and a second wafer comprising a second substrate are bonded. Moreover, a portion provided on a dicing line, of the first substrate is removed, whereby the first substrate is divided into a plurality of portions corresponding to a plurality of dies. Moreover, the first wafer and the second wafer are divided along the dicing line, whereby the plurality of dies are formed.
Next, semiconductor devices according to embodiments will be described in detail with reference to the drawings. Note that the following embodiments are merely examples, and are not shown with the intention of limiting the present invention. Moreover, the following drawings are schematic, and, for convenience of description, some configurations, and so on, thereof will sometimes be omitted. Moreover, portions that are common to a plurality of embodiments will be assigned with the same symbols, and descriptions thereof will sometimes be omitted.
Moreover, in the present specification, when a first configuration is said to be “electrically connected” to a second configuration, the first configuration may be connected to the second configuration directly, or the first configuration may be connected to the second configuration via the likes of a wiring, a semiconductor member, or a transistor. For example, even when, in the case of three transistors having been serially connected, the second transistor is in an OFF state, the first transistor is still “electrically connected” to the third transistor.
Moreover, in the present specification, when a first configuration is said to be “connected between” a second configuration and a third configuration, it will sometimes mean that the first configuration, the second configuration, and the third configuration are serially connected, and the second configuration is connected to the third configuration via the first configuration.
Moreover, in the present specification, when a circuit, or the like, is said to “make electrically continuous” two wirings, or the like, this will sometimes mean, for example, that this circuit, or the like, includes a transistor, or the like, that this transistor, or the like, is provided in a current path between the two wirings, and that this transistor, or the like, is in an ON state.
Moreover, in the present specification, a certain direction parallel to an upper surface of a substrate will be called an X direction, a direction parallel to the upper surface of the substrate and perpendicular to the X direction will be called a Y direction, and a direction perpendicular to the upper surface of the substrate will be called a Z direction.
Moreover, in the present specification, sometimes, a direction lying along a certain plane will be called a first direction, a direction intersecting with the first direction along this certain plane will be called a second direction, and a direction intersecting this certain plane will be called a third direction. These first direction, second direction, and third direction may correspond to any of the X direction, the Y direction, and the Z direction, but need not do so.
Moreover, when expressions such as “up” or “down” are used in the present specification, the semiconductor substrate provided with a bonding pad electrode, of two semiconductor substrates included in a die may be assumed to be an upper semiconductor substrate, and the semiconductor substrate not provided with a bonding pad electrode, of the two semiconductor substrates included in the die may be assumed to be a lower semiconductor substrate, for example. Furthermore, when a configuration included in the die is referred to, an orientation of coming closer to the upper semiconductor substrate along the above-described Z direction may be called up, and an orientation of coming closer to the lower semiconductor substrate along the Z direction may be called down, for example. Moreover, when a lower surface or a lower end is referred to for a certain configuration, this may be assumed to mean a surface or end portion on a lower semiconductor substrate side of this configuration, and when an upper surface or an upper end is referred to for a certain configuration, this may be assumed to mean a surface or end portion on an upper semiconductor substrate side of this configuration. Moreover, a surface intersecting with the X direction or the Y direction may be called a side surface, and so on.
Moreover, in the present specification, when the likes of a “width”, a “length”, or a “thickness” in a certain direction is referred to for a configuration, a member, and so on, this will sometimes mean a width, a length, or a thickness, and so on, in a cross section observed by the likes of SEM (Scanning Electron Microscopy) or TEM (Transmission Electron Microscopy), and so on.
[Memory System 10]
The memory system 10 performs read, write, erase, and so on, of user data, in response to a signal transmitted from a host computer 20. The memory system 10 is a memory chip, a memory card, an SSD, or another system capable of storing user data, for example. The memory system 10 comprises: a plurality of memory dies MD storing user data; and a controller die CD connected to these plurality of memory dies MD and to the host computer 20. The controller die CD comprises the likes of a processor and a RAM, for example, and performs processing, such as conversion of a logical address and a physical address, bit error detection/correction, garbage collection (compaction), and wear leveling.
As shown in
As shown in
Note that the configuration shown in
[Structure of Memory Die MD]
An upper surface of the chip CM is provided with a plurality of the bonding pad electrodes PX. Moreover, a lower surface of the chip CM is provided with a plurality of bonding electrodes PI1. Moreover, an upper surface of the chip CP is provided with a plurality of bonding electrodes PI2. Hereafter, regarding the chip CM, a surface thereof provided with the plurality of bonding electrodes PI1 will be called a front surface, and a surface thereof provided with the plurality of bonding pad electrodes PX will be called a back surface. Moreover, regarding the chip CP, a surface thereof provided with the plurality of bonding electrodes PI2 will be called a front surface, and a surface thereof on an opposite side to the front surface thereof will be called a back surface. In the example illustrated, the front surface of the chip CP is provided above the back surface of the chip CP, and the back surface of the chip CM is provided above the front surface of the chip CM.
The chip CM and the chip CP are disposed so that the front surface of the chip CM faces the front surface of the chip CP. The plurality of bonding electrodes PI1 are provided respectively correspondingly to the plurality of bonding electrodes PI2, and are disposed in positions enabling them to be bonded to the plurality of bonding electrodes PI2. The bonding electrodes PI1 and the bonding electrodes PI2 function as bonding electrodes for bonding and making electrically continuous the chip CM and the chip CP.
Note that in the example of
[Structure of Chip CM]
As shown in
As shown in
[Structure of Substrate Layer LSB of Chip CM]
As shown in
The semiconductor substrate 100 is a semiconductor substrate of the likes of silicon (Si) implanted with an N type impurity such as phosphorus (P) or a P type impurity such as boron (B), for example.
As shown in
These four regions R1 may be configured electrically independently from each other by a well structure, for example. In the case where, for example, the semiconductor substrate 100 is a P type semiconductor substrate including a P type impurity, the region R2 may be an N type well including an N type impurity. Moreover, the region R1 may be a P type well including a P type impurity.
Moreover, these four regions R1 may be configured electrically independently from each other by an insulating layer, for example. For example, the region R2 may have STI (Shallow Trench Isolation) including an insulating layer of the likes of silicon oxide (SiO2).
Moreover, these four regions R1 may be physically divided from each other, for example. For example, the semiconductor substrate 100 may comprise: four portions corresponding to the four region R1; and one portion corresponding to a region other than the four regions R1. Moreover, the region R2 may be a trench dividing these five portions.
Moreover, the semiconductor substrate 100 is provided with a plurality of contact holes, correspondingly to the plurality of input/output circuit regions RIO. As shown in
Moreover, the semiconductor substrate 100 is not provided in the edge region RE. Hence, in the case of the memory die MD being viewed from the Z direction, as shown in
Note that a roughness of side surfaces in the X direction and the Y direction of the semiconductor substrate 100 is smaller than a roughness of side surfaces in the X direction and the Y direction of the semiconductor substrate 200 in the chip CP.
Note that the semiconductor substrate 100 undergoes layer-thinning from a back surface side (an upper side in
The insulating layer 101 (
The insulating layer 102 is a passivation layer configured from an insulating material of the likes of a polyimide, for example. As shown in
The bonding pad electrode PX includes a conductive material such as aluminum (Al), for example. As shown in
The external connection region 104 is a region connected to the bonding wire B (
The internal connection region 105 is a region connected to a contact 112 included in the memory cell array layer LMCA. The internal connection region 105 covers the upper surface of the insulating layer 103 of the likes of silicon oxide (SiO2) included in the memory cell array layer LMCA, at the bottom surface of the contact hole provided in the semiconductor substrate 100.
Note that as shown in
[Structure of Memory Cell Array Layer LMCA of Chip CM]
As shown in
The memory block BLK comprises: a plurality of conductive layers 110 arranged in the Z direction; a plurality of semiconductor layers 120 extending in the Z direction; and a plurality of gate insulating films 130 (
The conductive layer 110 is a substantially plate-like conductive layer extending in the X direction. The conductive layer 110 may include a stacked film of a barrier conductive film of the likes of titanium nitride (TiN) and a metal film of the likes of tungsten (W), or the like. Moreover, the conductive layer 110 may include the likes of polycrystalline silicon including an impurity such as phosphorus (P) or boron (B), for example. An insulating layer of the likes of silicon oxide (SiO2) is provided between the plurality of conductive layers 110 arranged in the Z direction. These plurality of conductive layers 110 function for example as word lines and as gate electrodes of a plurality of memory cells connected to these word lines, and so on.
The semiconductor layer 120 functions for example as channel regions of the plurality of memory cells, and so on.
The semiconductor layer 120 is a semiconductor layer of the likes of polycrystalline silicon (Si), for example. The semiconductor layer 120 has a substantially circular columnar shape, for example. Moreover, an outer peripheral surface of the semiconductor layer 120 is surrounded by respective ones of the conductive layers 110, and faces the conductive layers 110.
A lower end portion of the semiconductor layer 120 is provided with an unillustrated impurity region including an N type impurity such as phosphorus (P). This impurity region is connected to a bit line BL via a contact 121 and a contact 122.
An upper end portion of the semiconductor layer 120 is provided with an unillustrated impurity region including an N type impurity such as phosphorus (P) or a P type impurity such as boron (B). This impurity region is connected to the semiconductor substrate 100.
Note that the semiconductor layer 120 exemplified in
The gate insulating film 130 (
Note that
Moreover, as shown in
The contact 112 includes for example a stacked film of a barrier conductive film of the likes of titanium nitride (TiN) and a metal film of the likes of tungsten (W), or the like. The contact 112 has a substantially cylindrical shape, for example. Upper ends of these plurality of contacts 112 are respectively connected to lower surfaces of the internal connection regions 105 of the bonding pad electrodes PX. Moreover, the plurality of contacts 112 are each connected at their lower ends to a wiring 141.
[Structure of Wiring Layers 140, 150, 160 of Chip CM]
A plurality of wirings included in the wiring layers 140, 150, 160 are electrically connected to at least one of configurations in the memory cell array layer LMCA and configurations in the chip CP, for example.
The wiring layer 140 includes a plurality of the wirings 141. These plurality of wirings 141 may include for example a stacked film of a barrier conductive film of the likes of titanium nitride (TiN) and a metal film of the likes of copper (Cu), or the like. Note that some of the plurality of wirings 141 function as the bit lines BL. The bit lines BL are arranged in the X direction and extend in the Y direction, for example. Moreover, these plurality of bit lines BL are respectively connected to the plurality of semiconductor layers 120.
The wiring layer 150 includes a plurality of wirings 151. These plurality of wirings 151 may include for example a stacked film of a barrier conductive film of the likes of titanium nitride (TiN) and a metal film of the likes of copper (Cu), or the like.
The wiring layer 160 includes a plurality of the bonding electrodes PI1. These plurality of bonding electrodes PI1 may include for example a stacked film of a barrier conductive film of the likes of titanium nitride (TiN) and a metal film of the likes of copper (Cu), or the like.
[Structure of Chip CP]
The chip CP comprises, for example: the semiconductor substrate 200; a transistor layer LTR provided above the semiconductor substrate 200; and a plurality of wiring layers 220, 230, 240, 250 provided above the transistor layer LTR. Moreover, the insulating layer 203 of the likes of silicon oxide (SiO2) is embedded between configurations in the transistor layer LTR and the wiring layers 220, 230, 240, 250. Note that it is possible too to employ as a material of the insulating layer 203 a material having a lower dielectric constant than a material of the insulating layer 103.
[Structure of Semiconductor Substrate 200 of Chip CP]
The semiconductor substrate 200 is a semiconductor substrate configured from P type silicon (Si) including a P type impurity such as boron (B), for example. A surface of the semiconductor substrate 200 is provided with a semiconductor substrate region 200S and an insulating region 200I.
The semiconductor substrate 200 is provided over all of the regions in the memory die MD including the edge region RE.
[Structure of Transistor Layer LTR of Chip CP]
The semiconductor substrate 200 has its upper surface provided with an electrode layer 210 via an insulating layer 200G. The electrode layer 210 includes a plurality of electrodes 211 that face the surface of the semiconductor substrate 200. Moreover, each of regions of the semiconductor substrate 200 and the plurality of electrodes 211 included in the electrode layer 210 are respectively connected to contacts 201.
The semiconductor substrate region 200S of the semiconductor substrate 200 functions as channel regions of a plurality of transistors Tr configuring the peripheral circuit, and so on.
The plurality of electrodes 211 included in the electrode layer 210 respectively function as gate electrodes of the plurality of transistors Tr configuring the peripheral circuit, and so on. The electrode 211 comprises: a semiconductor layer of the likes of polycrystalline silicon (Si) including an N type impurity such as phosphorus (P) or a P type impurity such as boron (B), for example; and a metal layer of the likes of tungsten (W) provided on an upper surface of this semiconductor layer.
The contact 201 extends in the Z direction and has its lower end connected to an upper surface of the semiconductor substrate 200 or electrode 211. The contact 201 may include for example a stacked film of a barrier conductive film of the likes of titanium nitride (TiN) and a metal film of the likes of tungsten (W), or the like.
Note that the plurality of transistors Tr provided in the semiconductor substrate 200 each configure part of the peripheral circuit.
[Structure of Wiring Layers 220, 230, 240, 250 of Chip CP]
A plurality of wirings included in the wiring layers 220, 230, 240, 250 are electrically connected to at least one of configurations in the transistor layer LTR and configurations in the chip CM, for example.
The wiring layer 220 includes a plurality of wirings 221. These plurality of wirings 221 may include for example a stacked film of a barrier conductive film of the likes of titanium nitride (TiN) and a metal film of the likes of copper (Cu), or the like.
The wiring layer 230 includes a plurality of wirings 231. These plurality of wirings 231 may include for example a stacked film of a barrier conductive film of the likes of titanium nitride (TiN) and a metal film of the likes of copper (Cu), or the like.
The wiring layer 240 includes a plurality of wirings 241. These plurality of wirings 241 may include for example a stacked film of a barrier conductive film of the likes of titanium nitride (TiN) and a metal film of the likes of copper (Cu), or the like.
The wiring layer 250 includes a plurality of the bonding electrodes PI2. These plurality of bonding electrodes PI2 may include for example a stacked film of a barrier conductive film of the likes of titanium nitride (TiN) and a metal film of the likes of copper (Cu), or the like.
[Method of Manufacturing Memory Die MD]
Next, a method of manufacturing the memory die MD will be described with reference to
In this method of manufacturing, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Note that, for example, when the step described with reference to
Next, a method of manufacturing a semiconductor memory device according to a comparative example will be described with reference to
In the method of manufacturing a semiconductor memory device according to the first embodiment, as described with reference to
Moreover, as shown in
In such a method, configurations between the semiconductor substrates 100A, 200A are readily subjected to stress by the dicing blade DB, and, sometimes, as exemplified in
[Advantages]
In the method of manufacturing a semiconductor memory device according to the first embodiment, as described with reference to
Moreover, in the method of manufacturing a semiconductor memory device according to the first embodiment, in the step described with reference to
Next, a configuration of a semiconductor memory device according to a second embodiment will be described with reference to
The semiconductor memory device according to the second embodiment is basically configured similarly to the semiconductor memory device according to the first embodiment. However, as described with reference to
Next, a method of manufacturing a semiconductor memory device according to the second embodiment will be described with reference to
In the method of manufacturing a semiconductor memory device according to the second embodiment, steps up to the step described with reference to
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Next, as described with reference to
The method of manufacturing a semiconductor memory device according to the second embodiment makes it possible for occurrence of a crack or film-peeling, and so on, to be more suitably suppressed compared to in the method of manufacturing according to the comparative example, similarly to in the first embodiment.
Moreover, in the method of manufacturing a semiconductor memory device according to the second embodiment, the metal layer ME is not left on the side surfaces in the X direction and the Y direction of the semiconductor substrate 100 when the wafers WM, WP are cut along the dicing line DL. Hence, the dicing line DL and the edge region RE can be made comparatively small. As a result, the number of memory dies MD manufacturable from one wafer can be increased, and manufacturing costs can thereby be reduced.
Next, a configuration of a semiconductor memory device according to a third embodiment will be described with reference to
The semiconductor memory device according to the third embodiment is basically configured similarly to the semiconductor memory device according to the second embodiment. However, as described with reference to
Next, a method of manufacturing a semiconductor memory device according to the third embodiment will be described with reference to
In the method of manufacturing a semiconductor memory device according to the third embodiment, steps up to the step described with reference to
Next, as shown in
Next, as shown in
Next, as shown in
Next, as described with reference to
The method of manufacturing a semiconductor memory device according to the third embodiment makes it possible for occurrence of a crack or film-peeling, and so on, to be more suitably suppressed compared to in the method of manufacturing according to the comparative example, similarly to in the first embodiment.
Moreover, the method of manufacturing a semiconductor memory device according to the third embodiment makes it possible for manufacturing costs to be reduced, similarly to in the second embodiment.
That concludes description of the semiconductor memory devices and methods of manufacturing the same according to the first through third embodiments. However, the semiconductor memory devices according to these embodiments are merely exemplifications, and specific configurations, methods, and so on, thereof may be appropriately adjusted.
For example, in the method of manufacturing according to the third embodiment, as described with reference to
Note that when such a method is executed, sometimes, as shown in
Note that a roughness of the surfaces 103a, 103b of the insulating layer 103 will sometimes be smaller than a roughness of side surfaces 103c in the X direction and the Y direction (for example, surfaces cut by the dicing blade DB) of the insulating layer 103.
Moreover, the mold resin 302 may be an insulating layer of the likes of a polyimide or an epoxy resin, for example. Moreover, the mold resin 302 may include a filler. Moreover, the bonding pad electrode PX of the structures shown in
Moreover, in the methods of manufacturing according to the first through third embodiments, for example, during dicing of the wafers WM, WP, the wafers WM, WP were cut by the dicing blade DB, as described with reference to
For example, it is conceivable too for a laser to be utilized during dicing of the wafers WM, WP. For example, it is conceivable for parts of configurations in the wafers WM, WP to be removed along the dicing line DL by the laser, and for cutting by the dicing blade DB to be subsequently performed. Moreover, it is conceivable too for damage to be caused to the configurations in the wafers WM, WP along the dicing line DL by the laser, and for the wafers WM, WP to be diced not by a dicing blade, but by a mechanical adaptive force.
Now, in the case of such a method employing a laser being adopted, there will be required a step in which one of the semiconductor substrates 100A, 200A is priorly removed along the dicing line DL. It is possible too for this step to be executed by a similar method to in the methods of manufacturing according to the first through third embodiments. In other words, in the methods of manufacturing according to the first through third embodiments, the above-mentioned kind of method employing a laser may be adopted instead of the step of the kind exemplified in
Moreover, in the semiconductor memory devices according to the first through third embodiments, the edge region RE of the memory cell array layer LMCA may be provided with the insulating layer 103 alone, as shown in
The plurality of insulating layers 110A or plurality of semiconductor layers are arranged in the Z direction correspondingly to the plurality of conductive layers 110, for example. Moreover, these plurality of insulating layers 110A may include the likes of silicon nitride (Si3N4), for example. Moreover, these plurality of semiconductor layers may include the likes of silicon (Si), for example. Moreover, an insulating layer of the likes of silicon oxide (SiO2), for example, may be provided between these plurality of insulating layers 110A or plurality of semiconductor layers.
The structure 120′ has a substantially circular columnar shape, for example. Moreover, an outer peripheral surface of the structure 120′ is surrounded by respective ones of the plurality of insulating layers 110A or plurality of semiconductor layers, and faces the plurality of insulating layers 110A or plurality of semiconductor layers. An upper end portion of the structure 120′ is connected to the semiconductor substrate 100. The structure 120′ may include the likes of silicon oxide (SiO2), may include the likes of silicon (Si), or may include another material, for example.
Note that the structure 120′ exemplified in
Moreover, in the first through third embodiments, a semiconductor memory device was exemplified as an aspect of the semiconductor device. However, it is possible for the configurations and methods of manufacturing of the kind exemplified in the first through third embodiments to be applied also to a semiconductor device other than a semiconductor memory device. As examples of such a semiconductor device, there may be cited the likes of an image sensor, sound sensor, or other sensor, a CPU (Central Processing Unit), GPU (Graphic Processing Unit), FPGA (Field Programmable Gate Array), or other arithmetic device, or a communication circuit, for example.
Moreover, in the first through third embodiments, a semiconductor substrate was exemplified as the substrate included in the two chips CM, CP. However, the substrate included in the two chips to be bonded may be a substrate other than a semiconductor substrate.
While certain embodiments have been described, these embodiments have been presented byway of example only, and are not intended to limit the scope of the inventions. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms: furthermore, various omissions, substitutions and changes in the form of the methods and systems 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.
Number | Date | Country | Kind |
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2021-030397 | Feb 2021 | JP | national |