US20080048327A1 - Electronic circuit with embedded memory - Google Patents

Abstract

Circuitry includes first and second circuits spaced apart by an interconnect region. The interconnect region includes a first interconnect and the second circuit includes a stack of semiconductor layers. The first interconnect extends between the first and second circuits to provide communication therebetween. The second circuit operates as a memory circuit.

Description

CROSS REFERENCE TO RELATED APPLICATIONS
• This application is a divisional of application Ser. No. 11/092,521, entitled “ELECTRONIC CIRCUIT WITH EMBEDDED MEMORY”, filed on Mar. 29, 2005, which claims priority to U.S. Pat. No. 7,052,941 filed on Jun. 21, 2004, the contents of both of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
• 1. Field of the Invention
• The present invention relates generally to semiconductor circuitry and, more particularly, to circuitry which includes memory devices.
• 2. Description of the Related Art
• Advances in semiconductor manufacturing technology have provided computer chips with integrated circuits that include many millions of active and passive electronic devices, along with the interconnects to provide the desired circuit connections. As is well-known, most integrated circuits include laterally oriented active and passive electronic devices that are carried on a single major surface of a substrate. Active devices typically include transistors and passive devices typically include resistors, capacitors, and inductors. However, these laterally oriented devices consume significant amounts of chip area.
• For example, a typical computer system includes a main computer chip with a processor circuit, a control circuit, and a memory cache that are carried on a single major surface of a substrate. The typical computer system also includes main memory which is positioned on a separate memory chip outside the main computer chip. Since the memory cache is positioned on the same substrate as the processor and control circuits in the main computer chip, it is often referred to as embedded memory.
• The memory cache typically includes fast and expensive memory cells, such as Static Random Access Memory (SRAM) cells, and the main memory typically includes slower and less expensive Dynamic Random Access Memory (DRAM) cells. Both SRAM and DRAM cells are larger than the devices included in the processor and control circuits, with SRAM cells being much larger than DRAM cells. As is well-known in the art, cache memory (L1 cache or L2 cache, for example) is used to store information from a slower storage medium or subsystem, such as the main memory or peripherals like hard disks and CD-ROMs, that is accessed frequently to increase the operation of the main computer chip.
• One reason the operation of the main computer chip is increased because its idle time is reduced. For example, when the processor circuit accesses the main memory, it does so in about 60 nanoseconds (ns). However, a typical processor circuit can have cycle times of about 2 nanoseconds. Hence, there are about 30 wasted cycles while the processor circuit accesses the main memory. As a result, the processor circuit is idle for many cycle times while it accesses the main memory.
• The processor circuit, however, can access the cache memory in about 10 ns to 30 ns, so the idle time is significantly reduced if the information needed is stored in the cache memory. The access time of the processor circuit to a hard disk is even slower at about 10 milliseconds (ms) to 12 ms, and the access time to a CD-ROM drive is about 10 times greater than this. Hence, cache memory uses a small amount of fast and expensive memory to allow the processor circuit faster access to information normally stored by a large amount of slower, less-expensive memory.
• With this in mind, it seems like the operation of the computer system can be speeded up even more by increasing the size of the cache memory so that it operates as the main memory or by embedding the main memory on the same substrate as the processor and control circuit and eliminating the cache memory altogether. However, there are several problems with doing this.
• One problem with doing this is cost. As mentioned above, the SRAM cells included in cache memory are larger and expensive, so increasing the size of the cache memory would significantly increase the cost of the computer chip. DRAM cells are less expensive and smaller, but to embed them with the main computer chip will still significantly increase the cost. One reason the cost increases for both embedded SRAM and DRAM cells is because the number of masks needed to fabricate the main computer chip increases. For example, to embed SRAM and DRAM memory cells with the main computer chip would require about 3-4 and 6-8 extra masks, respectively. This is because the masks used to fabricate the processor and control circuitry are not compatible with the masks used to fabricate SRAM and DRAM memory cells. Another reason the cost increases is because, as discussed below, the yield in manufacturing computer chips decreases as the size of the computer chip increases.
• Another problem is that in today's computer systems, the size of the main memory is much larger than the size of the cache memory. For example, in current state of the art systems, the main memory can store 256 MB to 1 GB in a single memory chip, but the cache memory can only store about 1 MB to 2 MB. This is because the size of the memory circuitry needed to store information in SRAM is much larger than that needed for DRAM. A conventional SRAM circuit includes six transistors to store one bit of information and a conventional DRAM circuit includes one transistor and one capacitor, which tend to be large, to store one bit of information.
• For example, the size of a conventional embedded SRAN cell is about 70-120 F²and the size of a conventional DRAM memory cell is about 15 F². As is known in the art, 1 F is the minimum photolithographic feature size. Hence, if the computer chip is being fabricated using 90 nm lithography, then 1 F corresponds to 90 nm and 1 F²corresponds to an area that it 90 nm by 90 nm in size. If the computer chip is being fabricated using 60 nm lithography, then 1 F corresponds to 60 nm and 1 F²corresponds to an area that it 60 nm by 60 nm in size. Thus, to increase the size of the cache memory by increasing the number of SRAM cells included therein would significantly increase the size of the computer chip and decrease its yield. Further, most of the area on the computer chip will be occupied by memory circuitry instead of processor and control circuitry.
• This presents several problems. As mentioned above, one problem is that the yield of computer chips in a manufacturing run decreases as their size increases. As is well-known in the art, several computer chips are fabricated from a single large wafer in a run. The individual computer chips carried by the wafer are typically referred to as die. Once the computer chips are fabricated, the die in the wafer are diced to provide separate chips. A wafer, however, has defects distributed throughout it surface which can negatively impact the operation of the computer chips. If the computer chip is larger in size, then it is more likely to include a defect from the wafer and if the computer chip is smaller in size, then it is less likely to include a defect from the wafer. Hence, smaller computer chips are less likely to be defective. Further, if the computer chip is smaller in size, then more of them can be fabricated from a single wafer, which also decreases costs. Hence, smaller computer chips increase the yield and decrease the costs.
• Another problem is that it is typically desirable to increase the number of devices included in the processor and control circuitry so that the processor can operate faster and perform more complicated operations. It is desirable for computer chips to be fast so they can process more data in a given amount of time. The speed of operation of a computer chip is typically measured in the number of instructions per second it can perform.
• Computer chips can be made to process more data in a given amount of time in several ways. In one way, the computer chip can include devices which are smaller, but this requires advances in lithography and increasingly expensive manufacturing equipment. As discussed above, they can also be made faster by decreasing the time it takes to perform certain tasks, such as storing or retrieving information to and from memory or other peripherals and subsystems.
• Computer chips can also be made faster by increasing the number of devices included therein so that more information can be processed in a given period of time. For example, if one processor operates on 32-bit data, then another processor that operates on 64-bit data can process information twice as fast because it can perform more instructions per second. However, the 64-bit processor will need more devices since there are more bits to process at a given time. Hence, if most of the area on the computer chip is occupied by memory cells, then there is less area for the processor and control circuitry to process data with a higher number of bits. The total area of the computer chip can be increased, but as discussed above, this decreases the yield and increases the cost.
• Accordingly, it is highly desirable to provide new structures and methods for fabricating computer chips which operate faster and cost effective to fabricate.
BRIEF SUMMARY OF THE INVENTION
• The present invention provides circuitry which includes first and second circuits and an interconnect region. A first interconnect is included in the interconnect region. The first interconnect extends above and between the first and second circuits to provide communication therebetween. A third circuit is positioned on the interconnect region and a second interconnect is included in the interconnect region. The second interconnect extends between the third circuit and at least one of the first and second circuits to provide communication therebetween.
• The present invention also provides circuitry which includes control and digital circuitry positioned on a substrate. An interconnect region is positioned on surfaces of the control and digital circuitry to provide communication therebetween. Memory circuitry is positioned on the interconnect region so that the interconnect region provides communication between the memory circuitry and the control circuitry.
• The present invention further provides circuitry which includes a substrate and first and second processor circuits carried by the substrate. A control circuit is carried by the substrate and positioned near the first and second processor circuits. An interconnect region is carried by and extends from the substrate. The interconnect region allows the first and second processor circuits to communicate with each other and the control circuit. A memory circuit is positioned on the interconnect region so that the memory circuit is electrically coupled to the control circuit through the interconnect region.
• These and other features, aspects, and advantages of the present invention will become better understood with reference to the following drawings, description, and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a simplified top view of a computer chip, in accordance with the present invention, with one processor positioned near a control circuit, the sectional view being taken along a cut line1-1′ ofFIG. 2.
• FIG. 2 is a simplified sectional view of the computer chip ofFIG. 1 taken along a cut-line2-2′ ofFIG. 1.
• FIG. 3ais a perspective view of a computer chip with memory devices positioned on the same substrate as the processor and control circuits.
• FIGS. 3b-3dare simplified perspective views of different computer chips in which the memory circuit is positioned above the processor and/or control circuits in accordance with the present invention.
• FIG. 4 is a more detailed view of a memory circuit shown inFIGS. 2 and 6.
• FIG. 5 is a simplified top view of a computer chip, in accordance with the present invention, with multiple processors separated by a control circuit, the sectional view being taken along a cut line5-5′ ofFIG. 6.
• FIG. 6 is a simplified sectional view of the computer chip ofFIG. 5 taken along a cut-line6-6′ ofFIG. 5.
• FIG. 7 is a simplified top view of another embodiment of a computer chip, in accordance with the invention, with multiple processor circuits and multiple control circuits.
• FIG. 8 is a simplified top view of another embodiment of a computer chip, in accordance with the present invention, with multiple processor circuits surrounded by a control circuit.
• FIG. 9 is a simplified top view of another embodiment of a computer chip, in accordance with the present invention, with multiple processors partially surrounded by multiple control circuits.
DETAILED DESCRIPTION OF THE INVENTION
• FIGS. 1 and 2 show simplified top and cross sectional views of acomputer chip100 which includes circuitry, in accordance with the present invention.FIG. 1 is a top view taken along a cut-line1-1′ ofFIG. 2 andFIG. 2 is a sectional view taken along a cut-line2-2′ ofFIG. 1. It should be noted that in the following figures, like reference characters indicate corresponding elements throughout the several views.
• In this embodiment,computer chip100 includes processor and control circuits which are carried by a substrate and coupled together so that signals can flow between them.Computer chip100 also includes a memory circuit positioned above the processor and control circuits. The memory circuit is spaced apart from the processor and control circuits by an interconnect region. The memory circuit is also coupled to the control circuit through the interconnect region so that signals can flow therebetween. In this way, the control circuit can receive output signals from the processor circuit and, in response, provide signals to and receive signals from the memory circuit. In response, the control circuit provides input signals to the processor circuit. It should be noted that a memory circuit is discussed here and throughout the disclosure for illustrative purposes and that, in other embodiments, the memory circuit can be replaced with other circuitry which can be fabricated in the same or a similar manner.
• A processor circuit typically executes a series of machine instructions to process data. It usually includes an ALU (Arithmetic/Logic Unit) to perform mathematical operations like addition, subtraction, multiplication and division. Modern processor circuits typically include floating point processors that can perform extremely sophisticated operations on large floating point numbers. A processor circuit provide commands to the control circuit to move data from one memory location to another in the memory circuit. A processor circuit can also make decisions and jump to a new set of instructions based on those decisions.
• One advantage ofcomputer chip100 is that the memory circuit is positioned above the control and processor circuits which is desirable since the memory circuit typically occupies much more area than the control and processor circuits. In some examples of a typical computer chip where the processor, control, and memory circuits are positioned on the same substrate, the memory circuit can occupy50% or more of the total area of the chip. An example of this is shown inFIG. 3a, which is a perspective view of acomputer chip110 with amemory circuit221 positioned on thesame substrate111 as processor andcontrol circuits144 and143. In this particular example,processor circuit144 andcontrol circuit143 occupy 30% and 20%, respectively, of the total area of the chip, andmemory circuit221 occupies 50%. It should be noted, however, that they can occupy different amounts of area than that shown here.
• FIGS. 3b-3dare simplified perspective views ofcomputer chips114,115, and116, respectively, which are similar or identical tocomputer chip100. InFIGS. 3b-3d,computer chips114,115, and116 each include asubstrate142 which carriesprocessor circuit144 andcontrol circuit143.Chip100 also includesmemory circuit121 positioned above and separated fromsubstrate142 by an interconnect region, which is not shown for simplicity. In the example shown inFIG. 3b,processor circuit144 andcontrol circuit143 include more electronic devices and occupy twice the area than they do incomputer chip110 shown inFIG. 3a. This may be desirable so thatcomputer chip114 can operate with data represented by a higher number of bits. This may also be desired so thatchip114 can perform more complicated operations, such as more accurate computations or pipelining. Further,memory circuit121 also occupies twice the area so that it can store more information, which speeds up the operation ofcomputer chip114.
• InFIG. 3c, the area ofcomputer chip115 is half the size ofcomputer chip110 shown inFIG. 3abecauseprocessor144 andcontrol circuit143 are the same size as that shown inFIG. 3a.Memory circuit121 is positioned abovesubstrate142 and extends over the same area asprocessor circuit144 andcontrol circuit143 combined. In this way,computer chip115 inFIG. 3coccupies half the area aschip110 and, consequently, is less expensive to fabricate because it has a higher yield and more chips can be fabricated on a single wafer.
• InFIG. 3d, the area ofcomputer chip116 is the same ascomputer chip110 shown inFIG. 3a, butprocessor144 andcontrol circuit143 are the same size as that shown inFIG. 3b.Memory circuit121 is positioned abovesubstrate142 and extends over the same area ascontrol circuit143, so its size is less than that shown inFIG. 3b. This may be useful in applications where a lot of memory is not needed. It should be noted thatmemory circuit121 can also be positioned overprocessor circuit142 or it can extend over both processor andcontrol circuits144 and143.
• It should also be noted that in some embodiments, the processor in the computer chip discussed herein can address memory devices on a separate chip positioned outside the computer chip. Further, in some embodiments, the computer chip can include embedded memory cells on the same surface as the control and processor circuits, in addition to the memory devices positioned above them. These memory devices can include a cache memory and/or ROM devices. For example the ROM devices can operate as a BIOS (Basic Input/Output System) for the computer system.
• Another advantage ofcomputer chip100 is that the memory circuit is positioned closer to the control and processor circuits so that signals can flow therebetween in less time. This speed up operation ofcomputer chip100 because the access time is reduced andcomputer chip100 is idle for fewer cycle times. Still another advantage ofcircuit100 is that the control and processor circuits are fabricated with a different mask set than the memory circuit. Hence, the masks are less complicated and less expensive to make. A further advantage is that the memory devices are fabricated from blanket semiconductor layers after they have been bonded to the interconnect region. Hence, the memory devices do not need to be aligned with the processor and/or control circuitry, which is a complicated and expensive process.
• In this embodiment,computer chip100 includescontrol circuit143 andprocessor circuit144 carried by substrate142 (FIG. 2).Computer chip100 also includesmemory circuit121 spaced apart fromprocessor circuit144 andcontrol circuit143 by aninterconnect region131. In this way,memory circuit121 is positioned aboveprocessor circuit144 andcontrol circuit143 as discussed above.Memory circuit121 is coupled to controlcircuit143 throughinterconnect region131 so that signals can flow therebetween.
• In this embodiment,substrate142 includes silicon, although it can include other materials which can support the subsequent structures positioned thereon. Other suitable substrate materials include gallium arsenide, indium phosphide, and silicon carbide, among others. It should be noted thatsubstrate142 can have portions doped n-type or p-type and some portions ofsubstrate142 can even be undoped. The preferred material forsubstrate142 in this invention is single crystalline material which can have defects, but is generally better material quality compared to amorphous or polycrystalline material.
• In this example,control circuit143 andprocessor circuit144 include digital circuitry known in the art. However, the digital circuitry is not shown in FIGS.1 or2 for simplicity and ease of discussion. The digital circuitry can include electronic devices, such as transistors, which extend intosubstrate142 and/or out ofsubstrate142 through asurface142a(FIG. 2).Processor circuit144 can operate in many different ways. For example,processor circuit144 can operate as a central processing unit, such as those commonly found in a computer chip, a signal processor, such as those commonly found in communication systems, or a microcontroller. In other examples,processor circuit144 can include analog circuitry, such as amplifiers and/or converters, for analog-to-digital converter applications.Control circuit143 includes circuitry typically found in periphery logic circuits which read, write, and erase semiconductor memory devices. This circuitry typically includes a sense amplifier, column selector, and/or a row selector which are used to communicate with memory devices, as will be discussed in more detail below.
• As shown inFIG. 2,interconnect region131 is positioned onsurface142aofsubstrate142.Interconnect region131 and regions subsequently positioned thereon are not shown inFIG. 1 for simplicity. Here,interconnect region131 includes an interlayer dielectric region (ILD)133 with interconnects extending betweensurface142aand asurface131aofregion131 so that signals can flow therethrough. Each interconnect typically includes one ormore interconnect lines135 and/or one ormore vias134.Interconnect region131 also typically includes one ormore contacts132 coupled to the electronic devices included incontrol circuit143 orprocessor circuit144.
• In accordance with the invention, the interconnects included ininterconnect region131 can be formed so that signals, such as signal S_a, can flow between the various devices included inprocessor circuit144. The interconnects can also be coupled together so that signals can flow betweencontrol circuit143 andprocessor circuit144. The interconnects, vias, and contacts can include conductive materials known in the art, such as aluminum (Al), copper (Cu), tungsten (W), titanium (Ti), or a doped semiconductor, among others.
• For example, signal S_acan flow betweenprocessor circuit144 andcontrol circuit143 through aninterconnect138aincluded ininterconnect region131, as shown inFIG. 2. Interconnect138aincludescontacts132aand132band aninterconnect line135a. Ends ofcontacts132aand132bare coupled toprocessor circuit144 andcontrol circuit143, respectively, and extend upwardly therefromsurface142a.Interconnect line135aextends between opposed ends ofcontacts132aand132b. Here,control circuit143 is positioned nearprocessor circuit144 so that the distance traveled by signals S_aflowing therebetween is reduced.
• In this embodiment, amemory circuit121 is positioned oninterconnect region131 and bonded to surface131a. The bonding can be done in many different ways. For example, the bonding can be done byheating bonding surface131aandcoupling memory circuit121 thereto. Sincememory circuit121 is bonded to interconnectregion131 instead of deposited thereon, it can include better quality semiconductor material. One reason the material is better quality is because it is more crystalline. It is more crystalline than polycrystalline material which is typically deposited on dielectric regions when wafer bonding is not used. More information about wafer bonding can be found in co-pending U.S. patent applications titled “SEMICONDUCTOR LAYER STRUCTURE AND METHOD OF MAKING THE SAME,” “SEMICONDUCTOR BONDING AND LAYER TRANSFER METHOD,” and “WAFER BONDING METHOD” filed on an even date herewith by the same inventor and incorporated herein by reference.
• Memory circuit121 includes abit line120apositioned onsurface131a. Adielectric region123 is positioned onsurface131aandbit line120a. Bit line vias124aextend upwardly therefrombit line120aand throughdielectric region123. The number of bit line vias124adepends on the number of devices it is desired to form inmemory circuit121. Each bit line via124ais coupled to anelectronic device124.
• Electronic device124 is typically a transistor or a memory device, although it can include other devices. The transistor can be a metal oxide semiconductor field effect transistor (MOSFET) and the memory device can be a negative differential resistance (NDR) static random access memory (SRAM) cell. An NDR SRAM includes a layer structure that operates as a transistor and a layer structure that operates as a thyristor. The transistor and thyristor are coupled together to operate as the NDR SRAM cell. More information regarding the NDR SRAM cell can be found in co-pending U.S. patent application titled “SEMICONDUCTOR MEMORY DEVICE” filed on the same date herewith by the same inventor and incorporated herein by reference.
• A reference line via124bis coupled to the opposite end of eachdevice124. Each reference line via124bextends upwardly from itscorresponding device124 where it connects to areference line120b. In this way, eachdevice124 is coupled between bit line and reference lines vias124aand124b. It should be noted, however, that in other embodiments,line120acan be used as a reference line andline120bcan be used as a bit line. Adielectric region148 is positioned ondielectric region123 andreference line120b.
• Memory circuit121 andinterconnect region131 include interconnects so that signals can flow betweencontrol circuit143 andbit line120aandreference line120b. In this particular example, areference interconnect136 extends throughregions133 and123 so that one end is coupled to controlcircuit143 and the opposite end is coupled toreference line120b. Similarly, abit interconnect137 extends throughregion133 so that one end is coupled to controlcircuit143 and the other end is coupled tobit line120a. Hence,control circuit143 can provide a bit signal tobit line120athroughinterconnect137 and a reference signal toreference line120bthroughinterconnect136. In this way,control circuit143 can communicate with the devices included indevice structure124. In other examples, thereference line120bcan be connected to an outside contact (not shown) which provides a reference voltage or current from outside of thecircuit100.
• In operation, various signals, such as signal S_a, can flow betweenprocessor circuit144 andcontrol circuit143. In response,control circuit143 provides signals to and receives signals frommemory circuit121 throughinterconnects136 and137. The signals can be to read, write, and/or erase information inmemory circuit121.Control circuit143 then provides input signals toprocessor circuit144. The input signals can be data values stored bymemory circuit121 thatprocessor circuit144 desires to process.
• FIG. 4 shows a more detailed sectional view ofmemory circuit121. In this particular example, eachelectronic device124 is a single transistor capacitorless dynamic random access memory (DRAM) device, althoughdevices124 can include other devices, such as a SONOS (Semiconductor Oxide Nitride Oxide Semiconductor) type nonvolatile memory device with a ONO (Oxide Nitride Oxide) dielectric. Here,device124 includes an n⁺pn⁻ stack of layers, although it can include other layer structures, such as a npn stack, a p⁺np⁺ stack, or a pnp stack. The n⁺pn⁺ stack includes an n⁺-type dopedregion125apositioned on bit line via124aand a p-type dopedregion125bpositioned onregion125b. An n⁺-type dopedregion125cis positioned onregion125cso that it is coupled betweenregion125band reference line via124b. Aninsulating region125dis positioned around the outer periphery of the stack ofregions125a,125b, and125c. Acontrol terminal125eis positioned around the outer periphery of insulatingregion125d.
• In this way, the conductivity ofregions125a,125b, and/or125ccan be adjusted in response to a word signal provided to control terminal125e. The word signal is provided bycontrol circuit143 through aword interconnect139.Word interconnect139 is coupled betweencontrol circuit143 and control terminal125eand extends throughdielectric regions123 and133 similar tointerconnects136 and137.Interconnect139,insulator region125d, and control terminal125eare not shown inFIG. 2 for simplicity.
• FIGS. 5 and 6 show simplified top and sectional views of acomputer chip101 in accordance with the present invention.FIG. 5 is a top view taken along a cut-line5-5′ ofFIG. 6 andFIG. 6 is a sectional view taken along a cut-line6-6′ ofFIG. 5. In this embodiment,chip101 includes multiple processors which can communicate with the control circuit and the memory circuit as discussed above in conjunction withFIGS. 1-2,3b-3d, and4. In this embodiment, however, the processors can also communicate with each other using an interface circuit (not shown) which provides better data flow between processors. The data flow is better because it can happen faster and with less noise so there are fewer errors in the signal.
• Computer chip102 includescontrol circuit143 andprocessors144a-144dwhich are carried by substrate142 (FIG. 6). Here,control circuit143 is positioned in a region that is cross-shaped from a top view (FIG. 5) so that it extends betweenprocessors144a-144d. In this way, the processors are separated from each other bycontrol circuit143. It should be noted that in this example,processors144a-144dcan be the same or similar toprocessor circuit144 discussed above in conjunction withFIGS. 1-2,3b-3d, and4.Interconnect region131 is positioned onsurface142aofsubstrate142 so that it coverscontrol circuit143 as well asprocessors144a-144d. However, in other embodiments,interconnect region131 can be positioned so that it covers only a portion oflogic circuit143,processor circuit144a,processor circuit144b,processor circuit144c, and/orprocessor circuit144d.
• Inchip101, various signals can flow betweenprocessors144a-144dandcontrol circuit143. For example, signal S_a, S_b, S_c, and S_dcan flow betweenprocessor circuit144a,144b,144c, and144d, respectively, andcontrol circuit143, as shown inFIG. 5. Signals can also flow betweenprocessors144a-144dwithout flowing throughcontrol circuit143. For example, signals S_ab, S_ac, S_bd, and S_cdcan flow betweenprocessors144a-144b,144a-144c,144b-144d, and144c-144d, respectively, as shown inFIG. 5. Signals S_ab, S_ac, S_bd, and S_cdcan flow through interconnects which extend throughinterconnect region131. The interconnects can be similar to interconnect138, but are not shown for simplicity.
• In a particular example, signal S_acan flow betweenprocessor circuit144aandcontrol circuit143 through aninterconnect138a, as shown inFIG. 6. Interconnect138aincludescontacts132aand132bandinterconnect line135a, as described above in conjunction withFIG. 2. Similarly, signal S_bcan flow betweenprocessor circuit144bandcontrol circuit143 through an interconnect138_b. Interconnect138_bincludescontacts132cand132dandinterconnect line135b. Ends ofcontacts132cand132dare coupled toprocessor circuit144bandcontrol circuit143, respectively, and extend upwardly therefrom.Interconnect line135bextends between opposed ends ofcontacts132cand132dso that signal S_bcan flow betweenprocessor circuit144bandcontrol circuit143. Signals S_cand S_dcan flow betweencontrol circuit143 andcorresponding processors144cand144dwith similar interconnects included ininterconnect region131.
• One advantage ofchip101 is that the distance betweencontrol circuit143 andprocessors144a-144dis reduced so that they can communicate with each other faster. This increases the speed ofcomputer chip100. Another advantage is that the design ofchip101 is convenient because eachprocessor circuit144a-144dcan have the same or a similar design which simplifies its fabrication.
• FIG. 7 is a top view of acomputer chip102 in accordance with the present invention.Chip102 includesprocessors144a-144dpositioned near each other in a manner similar to that ofchip101 shown inFIG. 5. Here, however, the control circuit includesseparate control circuits143a-143d. In this example,processors144aand144bare spaced apart bycontrol circuit143a,processors144band144dare spaced apart bycontrol circuit143b,processors144aand144care spaced apart bycontrol circuit143c, andprocessors144cand144dare spaced apart bycontrol circuit143d. It should be noted that eachcontrol circuit143a-143dcan be the same or similar tocontrol circuit143 shown inFIG. 4.
• Here, signals S_a1and S_b1flow betweencontrol circuit143aandprocessors144aand144b, respectively. Signals S_a2and S_c1flow betweencontrol circuit143candprocessors144aand144c, respectively. Signals S_b2and S_d1flow betweencontrol circuit143bandprocessors144band144_d, respectively. Signals S_c2and S_d2flow betweencontrol circuit143dandprocessors144cand144d, respectively.
• Signals S_a1, S_b1, S_a2, S_c1, S_b2, S_d1, S_c2, and S_d2flow between corresponding control circuits and processors through interconnects, similar tointerconnects138aand138b, as described above, in conjunction withFIG. 6. Signals S_ab, S_ac, S_bd, S_ad, S_bc, and S_cdflow betweencorresponding processors144a-144dthrough conductive lines which extend throughsubstrate142 or on itssurface142a. However, these conductive lines are not shown for simplicity. One advantage ofchip102 is that signals S_ab, S_ac, S_bd, S_cd, S_ad, and S_bc, can flowtherebetween processors144a-144dfaster so thatchip102 can operate faster. One reason the signals can flow faster is because the interconnects are shorter so the distance of travel is shorter and their capacitance is smaller.
• FIG. 8 is a top view of acomputer chip103 in accordance with the present invention.Chip103 includesprocessors144a-144dpositioned adjacent to each other. However, in this example,control circuit143 extends around an outer periphery ofprocessors144a-144d. In this way,processors144a-144dare surrounded bycontrol circuit143. Signals S_a, S_b, S_c, and S_dcan flow betweencontrol circuit143 andcorresponding processors144a-144dthrough interconnects, similar tointerconnects138aand138_b, as described above, in conjunction withFIG. 6. Similarly,processors144a-144dare coupled together so that signals S_ab, S_ac, S_bd, S_ad, S_bc, and S_cdcan flow therebetween as described above in conjunction withFIG. 7 above.
• FIG. 9 is a top view of acomputer chip104 in accordance with the present invention.Chip104 includesprocessors144a-144dpositioned near each other in a manner similar to that ofchip103 shown inFIG. 8. Here, however,control circuit143aextends along an outer periphery ofprocessors144aand144b. Similarly,control circuit143bextends along an outer periphery ofprocessors144band144d.Control circuit143cextends along an outer periphery ofprocessors144aand144candcontrol circuit143dextends along an outer periphery ofprocessors144cand144d.
• Signals S_a1, S_a2, S_b1, S_b2, S_c1, S_c2, S_d1, and S_d2can flow betweencorresponding control circuits143a-143dandcorresponding processors144a-144dthrough interconnects, similar tointerconnects138aand138b, as described above, in conjunction withFIG. 6. Similarly,processors144a-144dare coupled together so that signals S_ab, S_ac, S_bd, S_ad, S_bc, and S_cdcan flow therebetween as described above in conjunction withFIG. 6 above.
• The present invention is described above with reference to preferred embodiments. However, those skilled in the art will recognize that changes and modifications may be made in the described embodiments without departing from the nature and scope of the present invention. Various further changes and modifications will readily occur to those skilled in the art. To the extent that such modifications and variations do not depart from the spirit of the invention, they are intended to be included within the scope thereof.
• Having fully described the invention in such clear and concise terms as to enable those skilled in the art to understand and practice the same, the invention claimed is:

Claims (20)

1. Circuitry comprising:

a first circuit;

an interconnect region;

a first interconnect included in the interconnect region; and

a second circuit spaced apart from the first circuit by the interconnect region, the second circuit including a stack of semiconductor layers; and

wherein the first interconnect extends between the first and second circuits to provide communication therebetween.

2. The circuitry ofclaim 1, wherein the stack of semiconductor layers operates as a vertically oriented memory device.

3. The circuitry ofclaim 1, further including a third circuit positioned near the first circuit so that the second circuit is spaced apart from the first and third circuits by the interconnect region.

4. The circuitry ofclaim 3, further including a second interconnect extending through the interconnect region to provide communication between the first and third circuits.

5. The circuitry ofclaim 1, wherein the stack of semiconductor layers operates as a vertically oriented negative differential resistance static random access memory device.

6. The circuitry ofclaim 1, wherein at least a portion of the second circuit includes a crystalline semiconductor material region.

7. Circuitry comprising:

first and second circuits, the second circuit including a vertically oriented semiconductor device which includes a stack of semiconductor layers; and

an interconnect region which includes a first interconnect, the interconnect region extending between the first and second circuits;

wherein the first and second circuits are in communication with each other through the first interconnect.

8. The circuitry ofclaim 7, further including a third circuit positioned near the first circuit so that the second circuit is spaced apart from the first and third circuits by the interconnect region.

9. The circuitry ofclaim 8, wherein the interconnect region includes a second interconnect extending between the second and third circuits.

10. The circuitry ofclaim 8, further including a third interconnect which extends between the first and third circuits.

11. The circuitry ofclaim 7, wherein the vertically oriented semiconductor device operates as a memory device.

12. The circuitry ofclaim 7, wherein the vertically oriented semiconductor device operates as a negative differential resistance static random access memory device.

13. The circuitry ofclaim 7, wherein at least a portion of the third circuit includes a crystalline semiconductor material region.

14. The circuitry ofclaim 7, wherein the stack of semiconductor layers is bonded to the interconnect region.

15. Circuitry comprising:

an interconnect region which includes a first interconnect; and

first and second circuits in communication with each other through the first interconnect, the second circuit including a stack of semiconductor layers;

wherein the second circuit is bonded to the interconnect region.

16. The circuitry ofclaim 15, wherein the interconnect region extends between the first and second circuits.

17. The circuitry ofclaim 16, further including a third circuit, wherein the interconnect region extends between the second and third circuits.

18. The circuitry ofclaim 17, wherein first and third circuits include laterally oriented semiconductor devices.

19. The circuitry ofclaim 15, wherein second circuit does not include laterally oriented semiconductor devices.

20. The circuitry ofclaim 15, wherein second circuit includes a vertically oriented semiconductor device.

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