Composite Electrode Material Chemistry

Abstract

The present application relates to composite electrode material chemistry. A memory device may include: an access line; a memory element, the memory element including a chalcogenide; and an electrode, the electrode coupled to the memory element and the access line. The electrode may be made of a composition of a first material doped with a second material. The second material may include a tantalum-carbon compound. In some cases, the second material may be operable to be chemically inert relative to the memory element. The second material may include a thermally stable resistivity and have a lower resistance to signals transmitted between the access line and the memory element across an operating temperature range of the memory element compared to the resistance of the first material.

Description

[0001] Cross-references

[0002] This patent application claims priority to U.S. patent application No. 16 / 788,204, filed on February 11, 2020 by Zheng et al., entitled “COMPOSITE ELECTRODE MATERIAL CHEMISTRY,” which is assigned to the assignee of this application and is expressly incorporated herein by reference in its entirety.

[0003] The technical field relates to composite electrode material chemistry. Background Art

[0004] The following relates generally to one or more memory systems, and more particularly to composite electrode material chemistry.

[0005] Memory devices are widely used to store information in various electronic devices such as computers, wireless communication devices, cameras, digital displays, etc. Information is stored by programming memory cells within the memory device to various states. For example, a binary memory cell can be programmed to one of two supported states, usually represented by a logical 1 or a logical 0. In some instances, a single memory cell can support more than two states, any of which can be stored. In order to access the stored information, the component can read or sense at least one storage state in the memory device. In order to store information, the component can write or program a state in the memory device.

[0006] There are various types of memory devices and memory cells, including magnetic hard disks, random access memory (RAM), read-only memory (ROM), dynamic RAM (DRAM), synchronous dynamic RAM (SDRAM), ferroelectric RAM (FeRAM), magnetic RAM (MRAM), resistive RAM (RRAM), flash memory, phase change memory (PCM), self-selective memory, chalcogenide memory technology, etc. Memory cells can be volatile or non-volatile. Summary of the invention

[0007] A device is described. The device may include: an access line; a memory element including a storage element including a chalcogenide; and an electrode coupled to the memory element and the access line and including a composition of a first material doped with a second material, the second material including a tantalum-carbon compound, the second material operable to be chemically inert relative to the storage element of the memory element, the second material including a thermally stable resistivity and having a lower resistance to signals transmitted between the access line and the memory element across an operating temperature range of the storage element compared to a resistance of the first material.

[0008] A method is described. The method may include sputtering a composition of a tantalum-carbon compound with a first sputtering target and forming an electrode, the electrode comprising a composition of a first material doped with a second material, the second material comprising the composition of a tantalum-carbon compound, the second material operable to be chemically inert with respect to a memory element comprising a chalcogenide of the memory element, the second material comprising a thermally stable resistivity compared to a resistance of the first material and having a lower resistance to signals transmitted between an access line and the memory element across an operating temperature range of the memory element comprising the chalcogenide.

[0009] Another device is described. The device may include: a memory element including a memory element including a chalcogenide; a first electrode coupled to the memory element and a first access line and including a composition of a first material doped with a second material, the second material including a tantalum-carbon compound, the second material operable to be chemically inert relative to the memory element of the memory element, the second material including a thermally stable resistivity compared to a resistance of the first material and having a lower resistance to signals transmitted between the first access line and the memory element across an operating temperature range of the memory element; and a second electrode coupled to the memory element and a second access line and including a composition of a third material doped with a fourth material including carbon, the fourth material operable to be chemically inert relative to the memory element of the memory element, the fourth material including a thermally stable resistivity compared to a resistance of the third material and having a lower resistance to signals transmitted between the second access line and the memory element across an operating temperature range of the memory element. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 Examples of systems supporting composite electrode material chemistries according to examples disclosed herein are presented.

[0011] Figure 2Examples of memory dies supporting composite electrode material chemistries according to examples disclosed herein are shown.

[0012] Figure 3 Examples of memory cells supporting composite electrode material chemistries according to examples disclosed herein are presented.

[0013] Figure 4 Examples of compositions supporting composite electrode material chemistries according to examples disclosed herein are presented.

[0014] Figure 5 Examples of property maps supporting composite electrode material chemistry according to examples disclosed herein are shown.

[0015] Figure 6 Examples of property maps supporting composite electrode material chemistry according to examples disclosed herein are shown.

[0016] Figure 7 Examples of property maps supporting composite electrode material chemistry according to examples disclosed herein are shown.

[0017] Figure 8 Examples of property maps supporting composite electrode material chemistry according to examples disclosed herein are shown.

[0018] Fig. 9 Examples of property maps supporting composite electrode material chemistry according to examples disclosed herein are shown.

[0019] Fig. 10A -J shows an example of a memory device supporting composite electrode material chemistry according to the examples disclosed herein.

[0020] Fig.11 A flow chart is shown that illustrates one or more methods of supporting composite electrode material chemistry according to examples disclosed herein. DETAILED DESCRIPTION

[0021] Chalcogenide material compositions may be used in components or elements of memory devices that use chalcogenide materials to form storage elements. In some cases, memory cells having chalcogenide-based materials may experience high temperatures and large temperature fluctuations during operation. Chalcogenide materials with a higher tendency for large temperature fluctuations may limit the practicality and performance of devices that employ those compositions. For example, changes in temperature may affect the resistivity of electrodes coupled to chalcogenide materials. In some instances, affecting the resistivity of the electrodes may change the chemical bonding between the chalcogenide material and the electrode material, thereby causing the chalcogenide material to mix with the electrode material. In such cases, the effectiveness of the chalcogenide material and the overall performance of the memory device may be reduced.

[0022] The effects of temperature changes and resistivity changes of the electrode can be mitigated by introducing elements that increase stability into the electrode material. For example, the electrode can be formed by a material composition comprising a tantalum-carbon compound. The material comprising a tantalum-carbon compound can be chemically inert relative to a chalcogenide-based storage element. In some instances, the material comprising a tantalum-carbon compound can exhibit a relatively constant resistivity across a temperature range (e.g., elevated temperature) over which the chalcogenide-based material can operate. During the manufacturing process, the material can include an adjustable resistivity. The material can include increased thermal stability and thermally stable resistivity, thereby increasing the effectiveness and overall performance of the memory device. Incorporating tantalum-carbon compounds into the material composition of the electrode can stabilize the memory device to allow technology scaling and increased cross-point technology development (e.g., three-dimensional cross-point architecture, random access memory (RAM) deployment, storage deployment, etc.).

[0023] First, in the reference Figure 1-3 Features of the present disclosure are described in the context of the described systems, memory dies, and memory cells. Figure 4-1 The features of the present disclosure are described in the context of the figures described in FIG. Fig.11 These and other features of the present disclosure are further illustrated by and described with reference to the described flow charts relating to composite electrode material chemistry.

[0024] Figure 1 An example of a system 100 supporting composite electrode material chemistry according to examples disclosed herein is shown. The system 100 may include a host device 105, a memory device 110, and a plurality of channels 115 coupling the host device 105 to the memory device 110. The system 100 may include one or more memory devices, but aspects of the one or more memory devices 110 may be described in the context of a single memory device (e.g., memory device 110).

[0025] The system 100 may include portions of an electronic device such as a computing device, a mobile computing device, a wireless device, a graphics processing device, a vehicle, or other system. For example, the system 100 may illustrate aspects of a computer, a laptop computer, a tablet computer, a smart phone, a cellular phone, a wearable device, an Internet-connected device, a vehicle controller, etc. The memory device 110 may be a component of the system that is operable to store data for one or more other components of the system 100.

[0026] At least a portion of system 100 may be an instance of host device 105. Host device 105 may be an instance of a processor or other circuitry within a device that uses memory to perform processing, such as a computing device, a mobile computing device, a wireless device, a graphics processing device, a computer, a laptop computer, a tablet computer, a smart phone, a cellular phone, a wearable device, an Internet-connected device, a vehicle controller, or some other fixed or portable electronic device, among other instances. In some instances, host device 105 may refer to hardware, firmware, software, or a combination thereof that implements the functionality of external memory controller 120. In some instances, external memory controller 120 may be referred to as a host or host device 105.

[0027] The memory device 110 may be a stand-alone device or component operable to provide a physical memory address / space that may be used or referenced by the system 100. In some instances, the memory device 110 may be configured to work with one or more different types of host devices 105. Signaling between the host device 105 and the memory device 110 may be operable to support one or more of the following: modulation schemes for modulating signals, various pin configurations for transmitting signals, various form factors for physical packaging of the host device 105 and the memory device 110, clock signal delivery and synchronization between the host device 105 and the memory device 110, timing conventions, or other factors.

[0028] The memory device 110 may be operable to store data of components of the host device 105. In some instances, the memory device 110 may act as a slave device of the host device 105 (e.g., responding to and executing commands provided by the system 105 through the external memory controller 120). Such commands may include one or more of a write command for a write operation, a read command for a read operation, a refresh command for a refresh operation, or other commands.

[0029] Host device 105 may include one or more of an external memory controller 120, a processor 125, a basic input / output system (BIOS) component 130, or other components such as one or more peripheral components or one or more input / output controllers. The components of the host device may be coupled to each other using a bus 135.

[0030] The processor 125 can be operated to provide control or other functions for at least a portion of the system 100 or at least a portion of the host device 105. The processor 125 can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or a combination of these components. In such instances, the processor 125 can be an instance of a central processing unit (CPU), a graphics processing unit (GPU), a general-purpose GPU (GPGPU), or a system on a chip (SoC), among other instances. In some instances, the external memory controller 120 can be implemented by the processor 125 or be part of the processor.

[0031] The BIOS component 130 may be a software component including a BIOS operating as firmware that may initialize and run various hardware components of the system 100 or host device 105. The BIOS component 130 may also manage the flow of data between the processor 125 and the various components of the system 100 or host device 105. The BIOS component 130 may include a program or software stored in one or more of a read-only memory (ROM), flash memory, or other non-volatile memory.

[0032] The memory device 110 may include a device memory controller 155 and one or more memory dies 160 (e.g., memory chips) to support a desired capacity or specified capacity for data storage. Each memory die 160 may include a local memory controller 165 (e.g., local memory controller 165-a, local memory controller 165-b, local memory controller 165-N) and a memory array 170 (e.g., memory array 170-a, memory array 170-b, memory array 170-N). The memory array 170 may be a collection of memory cells (e.g., one or more grids, one or more libraries, one or more tiles, one or more segments), each of which is operable to store at least one bit of data. A memory device 110 including two or more memory dies may be referred to as a multi-die memory or a multi-die package or a multi-chip memory or a multi-chip package.

[0033] The memory die may include electrodes having a composite material chemistry. In some cases, the composition of the electrode of the nonvolatile phase change memory cell may have beneficial properties that may produce performance improvements relative to other memory architectures. For example, incorporating a tantalum-carbon compound into the material of the electrode may improve the performance of the memory device by allowing an adjustable resistivity of the electrode during the manufacturing process of the electrode material. In such cases, the electrode may provide a lower resistance to a signal transmitted between an access line and a memory element across the operating temperature range of the memory element, compared to the resistance of an electrode without the tantalum-carbon compound. In some cases, the material comprising the tantalum-carbon compound may be chemically inert relative to the storage element of the memory element, thereby increasing the effectiveness of the memory element.

[0034] The memory die 160 may be an example of a two-dimensional (2D) array of memory cells, or may be an example of a three-dimensional (3D) array of memory cells. A 2D memory die 160 may include a single memory array 170. A 3D memory die 160 may include two or more memory arrays 170, which may be stacked on top of each other or positioned adjacent to each other (e.g., relative to a substrate). In some examples, the memory arrays 170 in a 3D memory die 160 may be referred to as stacks, levels, layers, or dies. A 3D memory die 160 may include any number of stacked memory arrays 170 (e.g., two high, three high, four high, five high, six high, seven high, eight high). In some 3D memory dies 160, different stacks may share at least one common access line, such that some stacks may share one or more of the row lines or column lines.

[0035] The device memory controller 155 may include circuitry, logic, or components operable to control the operation of the memory device 110. The device memory controller 155 may include hardware, firmware, or instructions that enable the memory device 110 to perform various operations and may be operable to receive, transmit, or execute commands, data, or control information related to the components of the memory device 110. The device memory controller 155 may be operable to communicate with one or more of the external memory controller 120, the one or more memory dies 160, or the processor 125. In some examples, the device memory controller 155 may be combined with the local memory controller 165 of the memory die 160 to control the operation of the memory device 110 described herein.

[0036] A local memory controller 165 (e.g., local to the memory die 160) may be operable to control the operation of the memory die 160. In some instances, the local memory controller 165 may be operable to communicate (e.g., receive or transmit data or commands or both) with the device memory controller 155. In some instances, the memory device 110 may not include a device memory controller 155, and the local memory controller 165 or the external memory controller 120 may perform the various functions described herein. As such, the local memory controller 165 may be operable to communicate with the device memory controller 155, with other local memory controllers 165, or directly with the external memory controller 120 or the processor 125, or a combination thereof. Examples of components that may be included in the device memory controller 155 or the local memory controller 165, or both, may include a receiver for receiving signals (e.g., from the external memory controller 120), a transmitter for transmitting signals (e.g., to the external memory controller 120), a decoder for decoding or demodulating received signals, an encoder for encoding or modulating signals to be transmitted, or various other circuits or controllers operable to support the described operations of the device memory controller 155 or the local memory controller 165, or both.

[0037] The external memory controller 120 may be operable to enable communication of one or more of information, data, and / or commands between a component of the system 100 or host device 105 (e.g., the processor 125) and the memory device 110. The external memory controller 120 may convert or translate communications exchanged between a component of the host device 105 and the memory device 110. In some instances, the external memory controller 120 or other components of the system 100 or host device 105, or the functions thereof described herein, may be implemented by the processor 125. For example, the external memory controller 120 may be hardware, firmware, or software, or some combination thereof, implemented by the processor 125 or other components of the system 100 or host device 105. Although the external memory controller 120 is depicted as being external to the memory device 110, in some instances, the external memory controller 120 or the functions thereof described herein may be implemented by one or more components of the memory device 110 (e.g., the device memory controller 155, the local memory controller 165), or vice versa.

[0038] Components of the host device 105 can exchange information with the memory device 110 using one or more channels 115. The channels 115 can operate to support communication between the external memory controller 120 and the memory device 110. Each channel 115 can be an example of a transmission medium that carries information between the host device 105 and the memory device. Each channel 115 can include one or more signal paths or transmission media (e.g., conductors) between terminals associated with components of the system 100. A signal path can be an example of a conductive path that can be operated to carry a signal. For example, a channel 115 can include a first terminal that includes one or more pins or pads at the host device 105 and one or more pins or pads at the memory device 110. A pin can be an example of a conductive input or output point of a device of the system 100, and the pin can operate to act as part of a channel.

[0039] Channel 115 (and associated signal paths and terminals) can be dedicated to transmitting one or more types of information. For example, channel 115 can include one or more command and address (CA) channels 186, one or more clock signal (CK) channels 188, one or more data (DQ) channels 190, one or more other channels 192, or a combination thereof. In some instances, signaling can be transmitted through channel 115 using single data rate (SDR) signaling or double data rate (DDR) signaling. In SDR signaling, one signal modulation symbol (e.g., signal level) can be registered for each clock cycle (e.g., on the rising edge or falling edge of the clock signal). In DDR signaling, two signal modulation symbols (e.g., signal levels) can be registered for each clock cycle (e.g., on both the rising edge and the falling edge of the clock signal).

[0040] Figure 2 An example of a memory die 200 supporting a composite electrode material chemistry according to examples disclosed herein is shown. The memory die 200 may be a reference Figure 1 1. An example of a memory die 160 is described. In some examples, the memory die 200 may be referred to as a memory chip, a memory device, or an electronic memory device. The memory die 200 may include one or more memory cells 205 that may each be programmable to store a different logic state (e.g., a programmed one of a set of two or more possible states). For example, the memory cell 205 may be operable to store one bit of information at a time (e.g., a logical 0 or a logical 1). In some examples, the memory cell 205 (e.g., a multi-level memory cell 205) may be operable to store more than one bit of information at a time (e.g., a logical 00, a logical 01, a logical 10, a logical 11). In some examples, the memory cell 205 may be operable to store more than one bit of information at a time (e.g., a logical 00, a logical 01, a logical 10, a logical 11). Figure 1 The memory array 170 and the like are described as being arranged in an array.

[0041] The memory cell 205 may use a configurable material to store a logic state, and the configurable material may be referred to as a memory element, a memory storage element, a material element, a material storage element, a material portion, or a polarity write material portion, etc. The configurable material of the memory cell 205 may refer to a chalcogenide-based storage component, such as reference 200. Figure 3 205. For example, the chalcogenide memory element may be used in a phase change memory (PCM) cell, a threshold memory cell, or a self-selective memory cell. In some cases, the electrode material in contact with the chalcogenide memory element may be configured to be chemically inert relative to the material of the chalcogenide memory element of the memory cell 205.

[0042] The memory die 200 may include access lines (e.g., row lines 210 and column lines 215) arranged in a pattern such as a grid pattern. The access lines may be formed of one or more conductive materials. In some instances, the row lines 210 may be referred to as word lines. In some instances, the column lines 215 may be referred to as digit lines or bit lines. References to access lines, row lines, column lines, word lines, digit lines or bit lines, or the like, are interchangeable without loss of understanding or operation. The memory cells 205 may be positioned at the intersections of the row lines 210 and the column lines 215.

[0043] Operations such as reading and writing can be performed on the memory cell 205 by activating or selecting an access line, such as one or more of the row line 210 or the column line 215. By biasing the row line 210 and the column line 215 (e.g., applying a voltage to the row line 210 or the column line 215), a single memory cell 205 can be accessed at the intersection of the row line and the column line. In a two-dimensional or three-dimensional configuration, the intersection of the row line 210 and the column line 215 can be referred to as the address of the memory cell 205. The access line can be a conductive line coupled to the memory cell 205 and can be used to perform access operations on the memory cell 205.

[0044] Access to the memory cells 205 may be controlled by a row decoder 220 or a column decoder 225. For example, the row decoder 220 may receive a row address from the local memory controller 260 and activate the row lines 210 based on the received row address. The column decoder 225 may receive a column address from the local memory controller 260 and activate the column lines 215 based on the received column address.

[0045] The sensing component 230 can be operated to detect the state of the memory cell 205 (e.g., material state, resistance, threshold state) and determine the logic state of the memory cell 205 based on the stored state. The sensing component 230 can include one or more sense amplifiers for amplifying or otherwise converting the signal generated by accessing the memory cell 205. The sensing component 230 can compare the signal detected from the memory cell 205 with a reference 235 (e.g., a reference voltage). The detected logic state of the memory cell 205 can be provided as an output of the sensing component 230 (e.g., provided to the input / output 240) and the detected logic state can be indicated to another component of the memory device including the memory die 200.

[0046] The local memory controller 260 can control access to the memory cell 205 through various components (e.g., the row decoder 220, the column decoder 225, and the readout component 230). The local memory controller 260 can be a reference Figure 1 1. The local memory controller 165 of FIG. 1 is an example of a local memory controller 165 described herein. In some examples, one or more of the row decoder 220, the column decoder 225, and the readout component 230 can be co-located with the local memory controller 260. The local memory controller 260 can be operated to receive one or more of commands or data from one or more different memory controllers (e.g., an external memory controller 120 associated with the host device 105, another controller associated with the memory die 200), translate the commands or data (or both) into information that can be used by the memory die 200, perform one or more operations on the memory die 200, and transmit data from the memory die 200 to the host device 105 based on performing the one or more operations. The local memory controller 260 can generate row address signals and column address signals to activate the target row line 210 and the target column line 215. The local memory controller 260 can also generate and control various voltages or currents used during operations on the memory die 200. In general, the amplitude, shape, or duration of the applied voltage or current discussed herein may be varied and may be different for the various operations discussed in operating the memory die 200 .

[0047] The local memory controller 260 may be operable to perform one or more access operations on one or more memory cells 205 of the memory die 200. Examples of access operations may include write operations, read operations, refresh operations, precharge operations, or activate operations, among others. In some examples, access operations may be performed or otherwise coordinated by the local memory controller 260 in response to various access commands (e.g., from the host device 105). The local memory controller 260 may be operable to perform other access operations not listed here or other operations related to operating the memory die 200 that are not directly related to accessing the memory cells 205.

[0048] Figure 3 An example of a memory cell supporting a composite electrode material chemistry according to an example disclosed herein is shown. The memory array 300 may be a reference Figure 1 and 2 Memory array 300 may include a first stack 305 of memory cells positioned above a substrate and a second stack 310 of memory cells located on top of the first array or stack 305. Although the example of memory array 300 includes two stacks 305, 310, memory array 300 may include any number (e.g., one or more than two) of stacks.

[0049] The memory array 300 may further include row lines 210-a, row lines 210-b, row lines 210-c, row lines 210-d, column lines 215-a, and column lines 215-b, which may be examples of row lines 210 and column lines 215, as described with reference to FIG. Figure 2 In the pillars between the access lines, one or more memory cells of the first stack 305 and the second stack 310 may include one or more chalcogenide materials. For example, a single stack between the access lines may include one or more of a first electrode, a first chalcogenide material (e.g., a selector component), a second electrode, a second chalcogenide material (e.g., a storage element), or a third electrode. Although Figure 3 Some of the elements contained in the drawings are labeled with numerical indicators, but other corresponding elements are not labeled, but the other corresponding elements are the same or will be understood to be similar, in order to increase visibility and clarity of the depicted features.

[0050] One or more memory cells of the first stack 305 may include one or more of an electrode 325-a, a storage element 320-a, or an electrode 325-b. One or more memory cells of the second stack 310 may include an electrode 325-c, a storage element 320-b, or an electrode 325-d. The storage element 320 may be an example of a chalcogenide material, such as a phase change storage element, a threshold storage element, or a self-selective storage element. In some examples, the memory cells of the first stack 305 and the second stack 310 may have a common conductive line so that the corresponding memory cells of one or more stacks 305 and one or more stacks 310 may share a column line 215 or a row line 210. For example, the first electrode 325-c of the second stack 310 and the second electrode 325-b of the first stack 305 may be coupled to the column line 215-a so that the column line 215-a may be shared by vertically adjacent memory cells.

[0051] In some cases, electrode 325-a, electrode 325-b, electrode 325-c, electrode 325-d, or a combination thereof may include a tantalum-carbon compound. The material of electrode 325-a, electrode 325-b, or both may be chemically inert relative to storage element 320-a. The material of electrode 325-c, electrode 325-d, or both may be chemically inert relative to storage element 320-b. In some examples, the material of electrode 325-a, electrode 325-b, or both may provide a lower resistance to signals transmitted between access lines (e.g., row lines 210-c and column lines 215-a) and storage element 320-a across the operating temperature range of storage element 320-a compared to the resistance of the material of electrode 325-a, electrode 325-b, or both without the tantalum-carbon compound. In some instances, the material of electrode 325-c, electrode 325-d, or both can provide a lower resistance to signals transmitted between an access line (e.g., column line 215-a and row line 210-d) and a storage element 320-b across an operating temperature range of the storage element 320-b compared to the resistance of the material of electrode 325-c, electrode 325-d, or both without the tantalum-carbon compound.

[0052] In some examples, the material of the storage element 320 may include a chalcogenide material or other alloy, including selenium (Se), tellurium (Te), arsenic (As), antimony (Sb), carbon (C), germanium (Ge), silicon (Si) or indium (IN) or various combinations thereof. In some examples, a chalcogenide material having mainly selenium (Se), arsenic (As) and germanium (Ge) may be referred to as a SAG alloy. In some examples, the SAG alloy may also include silicon (Si), and such chalcogenide materials may be referred to as SiSAG alloys. In some examples, the SAG alloy may include silicon (Si) or indium (In) or a combination thereof, and such chalcogenide materials may be referred to as SiSAG alloys or InSAG alloys or a combination thereof, respectively. In some examples, the chalcogenide glass may include additional elements, such as hydrogen (H), oxygen (O), nitrogen (N), chlorine (Cl) or fluorine (F), each in the form of atoms or molecules.

[0053] In some examples, the storage element 320 may be an example of a phase change memory cell. In such examples, the material used in the storage element 320 may be based on an alloy (such as the alloys listed above) and may be operated so as to undergo a phase change or change to a different physical state during normal operation of the memory cell. For example, a phase change memory cell may have an amorphous state (e.g., a relatively disordered atomic configuration) and a crystalline state (e.g., a relatively ordered atomic configuration).

[0054] Phase change memory cells may exhibit observable differences between crystalline and amorphous resistances in phase change materials (which may be chalcogenide materials). Materials in a crystalline state may have atoms arranged in a periodic structure, which may result in relatively low resistance. In contrast, materials in an amorphous state may have no periodic atomic structure or a relatively small periodic atomic structure, which may have a relatively high resistance.

[0055] The difference in resistance values ​​between the amorphous and crystalline states of a material may be significant. For example, the resistance of a material in an amorphous state may be one or more orders of magnitude greater than the resistance of a material in a crystalline state. In some examples, a material may be partially amorphous and partially crystalline, and the resistance may be a value somewhere between the resistance of a material in a fully crystalline state or a fully amorphous state. In such examples, the material may be used to store more than two logical states (e.g., three or more logical states).

[0056] During a programming (writing) operation of a phase change memory cell (e.g., electrode 325-a, storage element 320-a, electrode 325-b), various parameters of the programming pulse can affect (e.g., determine, set, program) a specific behavior or characteristic of the material of the storage element 320, such as the threshold voltage of the material or the resistance of the material. In order to program a low resistance state (e.g., a relatively crystalline state) in a phase change memory cell, a programming pulse can be applied that heats or melts the material of the storage element 320, which can be associated with at least temporarily forming a relatively disordered (e.g., amorphous) atomic arrangement. The amplitude of the programming pulse can be reduced over a certain duration (e.g., relatively slowly) to allow the material to form a crystalline structure as it cools, thereby forming a stable crystalline material state. In order to program a high resistance state (e.g., a relatively amorphous state) in a phase change memory cell, a programming pulse can be applied that heats and / or melts the material of the storage element 320. The amplitude of the programming pulse can be reduced faster than the programming pulse for the low resistance state. In such a scenario, the material may be cooled with atoms in a more disordered atomic arrangement because the atoms cannot form a crystalline structure until the material reaches a stable state, thereby forming a stable amorphous material state. The difference in the threshold voltage or resistance of the material of the storage element 320 according to the logical state stored by the material of the storage element 320 may correspond to a readout window of the storage element 320. In some cases, a portion of the storage element may undergo a material change associated with a logical state.

[0057] In some instances, such as for a threshold memory cell or a self-selective memory cell, some or all of the logic states in the set of logic states supported by the memory cell may be associated with an amorphous state of a chalcogenide material (e.g., a material in a single state may be operable to store different logic states). In some instances, the storage element 320 may be an instance of a self-selective memory cell. In such instances, the material used in the storage element 320 may be an alloy (such as the alloys listed above) and may be operated so as not to undergo a phase change during normal operation of the memory cell (e.g., may not undergo a change between a relatively crystalline state and a relatively amorphous state). For example, the material of the storage element 320 may include a chemical element such as arsenic, which inhibits the chalcogenide material from changing state and may therefore remain in a single state (e.g., an amorphous state or a crystalline state). In some instances, such as for a self-selective memory cell, some or all of the logic states in the set of logic states supported by the memory cell may be associated with an amorphous state of a chalcogenide material (e.g., a material in a single state may be operable to store different logic states). For example, both logic state "0" and logic state "1" may be associated with an amorphous state of a chalcogenide material.

[0058] During a programming (writing) operation of a self-selective memory cell (e.g., comprising electrode 325-a, storage element 320-a, and electrode 325-b), the polarity used for the write operation can affect (determine, set, program) a particular behavior or characteristic of the material of storage element 320, such as the threshold voltage of the material. The difference in the threshold voltage of the material of storage element 320 according to the logical state stored by the material of storage element 320 (e.g., the difference in threshold voltage when the material is storing a logical state "0" versus a logical state "1") can correspond to a read window of storage element 320.

[0059] In some examples, the architecture of the memory array 300 may be referred to as a cross-point architecture, in which memory cells are formed at the topological intersections between the row lines 210 and the column lines 215. Such cross-point architectures may provide relatively high density data storage at a lower production cost than other memory architectures. For example, a cross-point architecture may have memory cells with reduced area and thus increased memory cell density compared to other architectures. For example, the memory cell area of ​​the architecture may be 4F2, where F is the minimum feature size, compared to other architectures (such as an architecture with a three-terminal selector element) having a memory cell area of ​​6F2, where F is the minimum feature size. For example, a DRAM may use a transistor as a three-terminal device as a selector element for each memory cell, and the memory cell area may be larger than that of a cross-point architecture.

[0060] Although Figure 3 The example of shows two memory stacks, but other configurations are possible. In some examples, memory cells of a single memory stack can be constructed above a substrate, which can be referred to as a two-dimensional memory. In some examples, memory cells of two or more stacks can be configured in a similar manner in a three-dimensional cross-point architecture. Further, in some cases, Figure 3 The elements shown in or described with reference to the figures may be electrically coupled to each other as shown or described, but may be physically rearranged (e.g., the storage element 320 and possible selection element or electrode 325 may be electrically connected in series between the row line 210 and the column line 215 but not necessarily in a pillar or stacked configuration).

[0061] Figure 4 An example of a material 400 supporting a composite electrode material chemistry according to an example disclosed herein is shown. The material 400 can include carbon 405, tantalum 410, and a tantalum-carbon compound 415. In some cases, the material 400 can be an example material of an electrode (e.g., see Figure 3 The material 400 may include a composite material, a doped material, a composite material, or a combination thereof.

[0062] In some systems, a pure carbon electrode can result in an irreversible resistivity through thermal cycling (e.g., changing temperature). In some cases, the resistivity of the electrode can be based on temperature. Chalcogenide-based memory elements can operate within a temperature range during normal operation. As the temperature changes, the resistivity of the electrode may change, which may affect the performance of the memory device more generally. If the pure carbon electrode reaches a temperature higher than the deposition temperature of the pure carbon, the reduction in resistivity may not be recoverable. For example, as the temperature of the electrode is repeatedly increased and then decreased, the resistivity of the carbon electrode may decrease over time. Once the electrode reaches a temperature range of 400-500 degrees Celsius, the resistivity of the carbon electrode can remain at the corresponding resistivity until the electrode is heated above the temperature range of 400-500 degrees Celsius.

[0063] During the temperature range of 400-500 degrees Celsius, aging may occur. Aging can be an example of the time and current required to reach a stable threshold voltage of the memory cell and / or a stable resistivity of the electrode. For example, when the memory cell is first manufactured, temperature changes initially cause several changes, and the memory cell becomes "aged" or reaches a stable state of performance after extended use. In some cases, changes in resistivity may result in increased cost and reduced reliability of the memory cell. In other instances, changes in the resistivity of the electrode can produce inconsistent thermal annealing and spike current effects during aging, thereby causing changes in voltage thresholds through cycling. In some cases, changes in resistivity may cause changes in threshold voltage during operating cycles. Cycling can be an example of a programming cycle that can change the threshold voltage when programming the memory cell.

[0064] In some cases, the top electrode and bottom electrode with thermally stable resistivity in the desired low resistivity range can be used for efficient aging (e.g., reducing aging current and circulation) to reduce the voltage threshold difference. In some cases, the manufacturing cost and production cost can be reduced by reducing the aging cycle time. However, in order to obtain a carbon or carbon nitride-based electrode with lower resistance, an electrode including a carbon or carbon nitride material with similar properties may cause damage to the cell material due to high temperature dependence and high deviation process. In some cases, the temperature dependence and thermal evolution of the electrode resistivity based on carbon and carbon nitride may cause the voltage threshold to change through circulation. The electrode can act as a protective element that protects the memory element from damage to the cell material. Therefore, it is desirable to improve the material and properties of the electrode.

[0065] In some examples, the material 400 of the electrode may include carbon 405, tantalum 410, and tantalum-carbon compound 415 (e.g., carbon 405 forms a bond with tantalum 410). For example, a first material (e.g., carbon 405 and tantalum 410) may be doped with tantalum-carbon compound 415 to form a second material. In other examples, the material 400 of the electrode may include carbon 405 and tantalum-carbon compound 415. For example, a first material (e.g., carbon 405) may be doped with tantalum-carbon compound 415 to form a second material.

[0066] Carbon 405 may be an example of amorphous carbon. Due to the opposite thermal dependencies of tantalum 410 and carbon 405, the resistivity of material 400 may be thermally stable (e.g., having high stability under electrothermal stress). For example, the opposite thermal dependencies may be an example of different temperature dependencies of the resistivity of tantalum 410 and carbon 405. Due to the resistivity of carbon 405 and the different resistivity ranges of carbon 405 (e.g., 100-5000 μ Ohm cm), material 400 may also be thermally stable. For example, material 400 may include a stable resistivity across the operating temperature range. In such cases, material 400 may include a material having a low resistivity (e.g., 10-100 μ Ohm-cm) of a metal (e.g., tantalum 410) or a metal carbide (e.g., tantalum-carbon compound 415).

[0067] Material 400 can be chemically inert relative to the material of the memory element while allowing thermal stability and reduced resistivity. For example, carbon 405 can make material 400 chemically inert relative to the material of the memory element. Material 400 can be chemically stable so as to prevent reaction with the cell material (e.g., the chalcogenide material of the memory element). As the temperature of the memory cell (e.g., during a programming pulse) increases, the cell material may become more reactive. The absence of carbon 405 may cause a reaction between the material of the electrode and the material of the memory element. In such cases, the memory device can form new compounds based on the reaction, thereby changing the electrical properties of the cell material, changing the resistivity, and changing the volume of the cell material. In such cases, the cell material may lose the ability to store data and reduce the efficiency of the memory device. Therefore, the presence of carbon 405 in material 400 can expand the positioning of electrons, thereby increasing the conductivity and overall performance of the memory device.

[0068] The material 400 can provide a lower resistance to a signal transmitted between an access line and a memory element across an operating temperature range of the memory element compared to the resistance of a composition without the tantalum-carbon compound 415. In order to provide a low resistance to the signal, the material 400 can include an increased amount of tantalum 410 relative to carbon 405 to reduce the resistance. In some examples, the material 400 can include a large amount of carbon 405 relative to tantalum 410. In some cases, the ratio of carbon to tantalum can be 1:1 or 2:1 or much more (e.g., tantalum can include 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5% or other percentages of the composition). The material 400 (e.g., carbon 405) can be adjusted by adding tantalum 410 to adjust the resistivity of the material 400. The material 400 including a composition of carbon 405 and tantalum-carbon compound 415 can allow for adjustable resistivity across the operating temperature of the memory device during the manufacturing process to provide optimal resistivity characteristics at different operating temperatures during operation. In such cases, material 400 may be formed to have a desired resistivity for operation.

[0069] In some cases, the amount of tantalum 410 in material 400 can vary. For example, the amount of tantalum-carbon compound 415 can be less than or equal to 10 atomic percent (at.%) of material 400. The amount of tantalum-carbon compound 415 can be less than or equal to 94.8 at.% of material 400. The amount of tantalum 410 can be equal to 3.2 at.% of material 400. In other examples, the amount of tantalum 410 can be equal to 3.4 at.% of material 400. In some cases, the amount of tantalum in material 400 can range between 2.6 at.% and 4.0 at.%, between 2.7 at.% and 3.9 at.%, between 2.8 at.% and 3.8 at.%, between 2.9 at.% and 3.7 at.%, between 3 at.% and 3.6 at.%, between 3.1 at.% and 3.5 at.%, or about 3.2 at.%, or about 3.3 at.%, or about 3.4 at.%.

[0070] The resistivity of the material 400 can be reduced by the presence of the tantalum-carbon compound 415 while also maintaining the high thermal stability of the material 400. Tantalum-based compounds (e.g., tantalum-carbon compounds 415) can contain higher cohesive energy values, where cohesive energy can be an example of energy required for bonds and structures. In such cases, the tantalum-carbon compound 415 can contain high bond energy associated with the bond formation between the tantalum 410 and the carbon 405. High thermal stability may be associated with an increase in bond strength. In some instances, the tantalum-carbon compound 415 can provide optimal resistivity characteristics at different operating temperatures compared to carbon-based electrodes, thereby mitigating the impact of temperature evolution on cell performance. For example, adding the tantalum-carbon compound 415 to the material 400 can also enable the electrode to operate in the range of 0.1-10mohm-cm at cell aging and cycling temperatures of 450 degrees Celsius.

[0071] The resistivity of material 400 may depend on the amount of tantalum 410 in material 400. For example, the resistivity of material 400 may increase as the amount of tantalum 410 decreases. In such cases, the resistivity of material 400 including tantalum 410 in an amount equal to 94.8 at. % of material 400 may be lower than the resistivity of material 400 including tantalum 410 in an amount less than or equal to 10 at. % of material 400.

[0072] In some cases, the surface peak fitting results can be studied for the amount of tantalum 410 and carbon 405 in the material 400. For example, the surface tantalum peak fitting can show both tantalum 410 and tantalum-carbon compound 415 with increased bond energy. The tantalum-carbon compound 415 can include tantalum carbide in a ratio of 1:1 (e.g., one tantalum to one carbon). In some cases, the tantalum-carbon compound 415 or tantalum 410 can oxidize at the surface of the material 400 after exposure to air or annealing. The surface carbon peak fitting can show both carbon 405 and tantalum-carbon compound 415.

[0073] In other examples, the transition metal can be bonded to carbon (e.g., to form a transition metal carbide) to reduce resistivity. Transition metal carbides or transition metal nitrides can be a class of refractory materials suitable for having high thermal stability, low resistivity, and high melting temperatures. In some examples, the resistivity of the carbide can increase with increasing temperature. For example, the resistivity of carbides such as TiC, W2C, HfC, TaC, ZrC, and NbC can increase with increasing temperature to 2,000 degrees Celsius. In other examples, the resistivity of Mo2C can increase with increasing temperature to 800 degrees Celsius. The resistivity of Mo2C can be maintained as the temperature increases from 800 degrees Celsius to 2,000 degrees Celsius.

[0074] Transition metals combined with carbon, nitrogen, or both may include high thermal stability due to high bond energy and metal-like capabilities. In such cases, the resistivity of the material containing the transition metal combined with carbon, nitrogen, or both may include an optimal resistivity at various operating temperatures. In some cases, the electrode material (e.g., comprising a transition metal) may produce the results identified in Table 1.

[0075]

[0076] Table 1

[0077] As shown in Table 1, the enthalpy column heading may represent the internal energy of the system plus the product of its pressure and volume. For example, the enthalpy of TaN may be 6.33 eV / atom. As shown in Table 1, the melting point (T m ) column headings can represent the temperature at which a material changes from a solid to a liquid. For example, TaN may have a melting point of 3,090 degrees Celsius.

[0078] Figure 5 An example of a property plot 500 supporting a composite electrode material chemistry according to an example disclosed herein is shown. Plot 500 may include line 505, which may represent a material comprising 6.2 at.% tantalum. Line 510 may represent a material comprising 6.4 at.% tantalum. Line 515 may represent a material comprising 35.7 at.% tantalum. Line 520 may represent a material comprising 86.1 at.% tantalum. Line 525 may represent a material comprising 94.8 at.% tantalum. Plot 500 may show the state of an electrode after a heat treatment (e.g., represented on the x-axis) is applied to the electrode.

[0079] In some cases, the resistivity of the material can be reduced by the presence of tantalum-carbon compounds. In such cases, the material can maintain high thermal stability while reducing resistivity. In some cases, the resistivity of the electrode material across the operating temperature range of the memory element can be in the range of 0.1-10mohm-cm. The resistivity of the electrode material can be adjusted during the manufacturing process. In such cases, the desired target resistivity can be achieved by selecting the composition of the electrode. In some instances, the electrode material increases the thermal stability of the electrode across the operating temperature range of the memory element.

[0080] The electrode material maintains a low resistivity as the electrode temperature increases. For example, as the temperature of an electrode including a material containing 6.2 at.% tantalum increases, the resistivity of the electrode can be maintained. As the temperature of an electrode including a material containing 6.4 at.% tantalum increases, the resistivity of the electrode can be maintained. Similarly, as the temperature of an electrode including a material containing 35.7 at.% tantalum, 86.1 at.% tantalum, or 94.8 at.% tantalum increases, the resistivity of each electrode can be maintained. In such cases, the resistivity shown in plot 500 can show minimal temperature dependence within a temperature range of up to 750 degrees Celsius.

[0081] In some cases, the resistivity can vary based on the application of the heat treatment. For example, plot 500 can show a heat treatment at 350 degrees Celsius, a heat treatment at 1150 degrees Celsius, and a heat treatment at 750 degrees Celsius. The resistivity of a material containing 35.7 at.% tantalum under a heat treatment at 750 degrees Celsius can be higher than the resistivity of a material containing 35.7 at.% tantalum under a heat treatment at 350 degrees Celsius. In other examples, the resistivity of a material containing 6.4 at.% tantalum under a heat treatment at 750 degrees Celsius can be higher than the resistivity of a material containing 6.4 at.% tantalum under a heat treatment at 1150 degrees Celsius.

[0082] As illustrated by plot 500, the material can be thermally stable (e.g., maintain a stable resistivity) through standard heat treatment and aggressive heat treatment. For example, the resistivity of a material comprising 94.8 at. % tantalum can be stable across heat treatments at 350 degrees Celsius, 1150 degrees Celsius, and 750 degrees Celsius. In other examples, the resistivity of a material comprising 6.2 at. % tantalum can be stable across heat treatments at 350 degrees Celsius, 1150 degrees Celsius, and 750 degrees Celsius.

[0083] Figure 6 An example of a property plot 600 supporting a composite electrode material chemistry according to an example disclosed herein is shown. Plot 600 can include line 605, which can represent a material comprising 3.6 at.% tantalum during a first heating process. Line 610 can represent a material comprising 3.6 at.% tantalum during a first cooling process. Line 615 can represent a material comprising 3.6 at.% tantalum during a second heating process. Line 620 can represent a material comprising 3.6 at.% tantalum during a second cooling process.

[0084] In some cases, the resistivity of a material doped with a tantalum-carbon compound may result in minimal temperature dependence. For example, for a material doped with a tantalum-carbon compound and including tantalum in an amount equal to 3.6 at.% of the material, the resistivity may remain stable (e.g., resist increasing or decreasing) as the temperature of the material increases. In such cases, the resistivity of a material doped with a tantalum-carbon compound and including tantalum in an amount equal to 3.6 at.% of the material may maintain a lower resistivity (e.g., less than 0.01 ohm-cm) over an operating temperature range compared to the resistivity of the material without the tantalum-carbon compound.

[0085] Figure 7 An example of a property plot 700 supporting a composite electrode material chemistry according to an example disclosed herein is shown. Plot 700 can include line 705, which can represent a material comprising 3.2 at.% tantalum during a first heating process. Line 710 can represent a material comprising 3.2 at.% tantalum during a first cooling process. Line 715 can represent a material comprising 3.2 at.% tantalum during a second heating process. Line 720 can represent a material comprising 3.2 at.% tantalum during a second cooling process.

[0086] In other examples, for a material doped with a tantalum-carbon compound and including tantalum in an amount equal to 3.2 at.% of the material, the resistivity may remain stable (e.g., resist increasing or decreasing) as the temperature of the material increases. In such cases, the resistivity of the material doped with a tantalum-carbon compound and including tantalum in an amount equal to 3.2 at.% of the material may maintain a lower resistivity (e.g., less than 0.01 ohm-cm) over the operating temperature range compared to the resistivity of the material without the tantalum-carbon compound. In some cases, the resistivity of the material may be independent of temperature.

[0087] Figure 8 An example of a characteristic plot 800 of a supporting composite electrode material chemistry according to an example disclosed herein is shown. Curve 800 may include region 805 and region 810. Region 805 may represent the ratio of tantalum-carbon target power to carbon target power for a range of compositions (e.g., based on the atomic percentage of tantalum). The compositions in region 805 may include a composition including 8.4 at.% tantalum, a composition including 7.3 at.% tantalum, a composition including 35.7 at.% tantalum, and a composition including 94.8 at.% tantalum. Region 810 may represent the ratio of tantalum-carbon target power to carbon target power for a range of compositions (e.g., based on the atomic percentage of carbon). The compositions in region 810 may include a composition including approximately 93 at.% carbon, a composition including approximately 91 at.% carbon, a composition including approximately 83 at.% carbon, and a composition including approximately 2 at.% carbon.

[0088] The substrate may be sputtered with a composition of a tantalum-carbon compound using a first sputtering target. In such cases, an electrode may be formed that includes a first material doped with a second material that includes a composition of a tantalum-carbon compound. The second material (e.g., including a tantalum-carbon compound) may be chemically inert relative to a chalcogenide material of the memory element, include a thermally stable resistivity, and include a lower resistance to signals transmitted between an access line and the memory element across an operating temperature range of the memory element compared to the resistance of the first material (e.g., without the tantalum-carbon compound).

[0089] In some cases, the substrate can be co-sputtered with carbon and tantalum-carbon compounds. Co-sputtering can occur during a physical vapor deposition (PVD) process to provide composition and bond control. For example, the co-sputtering technique can include applying a PVD process to a provided substrate to control bond formation between carbon and the tantalum-carbon compound. Co-sputtering of the tantalum-carbon compound and carbon can be deposited without bias at low temperatures (e.g., less than 100 degrees Celsius) by PVD sputtering to minimize the impact on the unit material in the layer below the electrode.

[0090] For example, a substrate can be sputtered (e.g., co-sputtered) with carbon using a second sputtering target that is different from the first sputtering target. In some cases, the first sputtering target can sputter a composition of a tantalum-carbon compound after the second sputtering target can sputter carbon. In other examples, the first sputtering target can sputter a composition of a tantalum-carbon compound before the second sputtering target can sputter carbon. Alternating sputtering with the first sputtering target and the second sputtering target can form a multilayer electrode composition that can depend on the sputtering time. For example, co-sputtering can allow a user to change the composition of a material without breaking a vacuum using a target set. In some cases, co-sputtering can be performed by sputtering with the first sputtering target and the second sputtering target simultaneously.

[0091] As illustrated in plot 800, the target power ratio of tantalum-carbon to carbon can be adjusted to obtain different bonding percentages (e.g., different compositions) to control the bonds formed. Controlling the bonding percentage by optimizing the power density of the respective compositions deposited with each target can produce a composition including a tantalum-carbon compound in which the amount of carbon can be greater than the amount of tantalum. In such cases, the atomic percentage of tantalum (e.g., the ratio of tantalum to carbon) can be controlled.

[0092] In some cases, sputtering the composition of the tantalum-carbon compound can include a first power density for depositing the composition with a first sputtering target, and sputtering the carbon can include a second power density different from the first power density for depositing the carbon with a second sputtering target. When applying the tantalum-carbon compound and the carbon to the substrate, the target can be an example of a source. The stoichiometry (e.g., bonding percentage) can be controlled by optimizing the power density for depositing the tantalum-carbon compound and the carbon with each target, respectively. The power density can be an example of the power for applying the tantalum-carbon compound and the carbon to the substrate.

[0093] The two or more targets may have different power ratios. The power ratio may be an example of a ratio of the power at the output of the amplifier to the power at the input of the amplifier. In such cases, the ratio of the tantalum-carbon target power to the carbon target power may be the ratio of the power output at the tantalum-carbon compound sputtering target (e.g., the first sputtering target) to the power output at the carbon sputtering target (e.g., the second sputtering target). In region 805, the ratio of the tantalum-carbon target power to the carbon target power may increase with an increase in the atomic percentage of tantalum in the electrode material. In region 810, the ratio of the tantalum-carbon target power to the carbon target power may increase with an increase in the atomic percentage of carbon in the electrode material.

[0094] Fig. 9 An example of a property plot 900 supporting composite electrode material chemistry according to examples disclosed herein is shown. Plot 900 can include region 905 and region 910. Region 905 can represent tantalum carbon versus power. Region 910 can represent resistivity versus power. Plot 900 can also include representations of sputtering electrode materials using a direct current (DC) power source 915, a pulsed direct current (PDC) power source 920, and a radio frequency (RF) power source.

[0095] Tantalum-carbon compounds can be sputtered at a substrate with a single target. The target can be powered by different power sources such as a DC power source or a PDC power source to control the composition of the material doped with the tantalum-carbon compound, thereby controlling the resistivity. For example, sputtering tantalum-carbon compounds with different power sources may result in different tantalum-carbon ratios. For example, in region 905, as the DC power source 915 increases, the tantalum-to-carbon ratio increases. In some cases, as the PDC power source 920 increases, the tantalum-to-carbon ratio increases. As the RF power source 925 increases, the tantalum-to-carbon ratio increases.

[0096] The target can be powered by different power sources such as a DC power supply or a PDC power supply to control the resistivity of the electrode material. In such cases, increasing the power supplied to the power supply can reduce the resistivity of the material doped with the tantalum-carbon compound. For example, in region 910, as the power supplied to the DC power supply 915 decreases, the resistivity of the material doped with the tantalum-carbon compound decreases. In some cases, as the power supplied to the PDC power supply 920 decreases, the resistivity of the material doped with the tantalum-carbon compound decreases. As the power supplied to the RF power supply 925 decreases, the resistivity of the material doped with the tantalum-carbon compound decreases.

[0097] The material may be sputtered with a sputtering target to form an electrode including a second material including a tantalum-carbon compound. In such cases, the second material may be chemically inert relative to the chalcogenide material of the memory element, include a thermally stable resistivity, and include a lower resistance to signals transmitted between an access line and the memory element across an operating temperature range of the memory element compared to a material without the tantalum-carbon compound. For example, the sputtering technique may include depositing carbon on a substrate and depositing tantalum on the substrate simultaneously with the carbon deposition.

[0098] In some cases, the sputtering target is powered by a DC power supply. A DC power supply can be used with a conductive target material (e.g., a substrate). In contrast to other power supplies (e.g., a PDC power supply, an RF power supply, etc.), using a DC power supply can be cost effective and easier to control deposition. For example, using a DC power supply can control bond formation by depositing carbon and tantalum simultaneously with a current power supply.

[0099] In some cases, the sputtering target is powered by a PDC power supply. The PDC power supply can be configured to adjust the frequency of depositing carbon and tantalum. For example, the PDC power supply can include a variable frequency. Voltage regulation is achieved by changing the on-off time ratio (e.g., duty cycle). In some cases, a bipolar PDC power supply can use two pulses to deposit carbon and tantalum. In some cases, the PDC power supply can be sputtered by PVD technology to control bond formation. For sputtering of metals (e.g., tantalum) and dielectric coatings that are insulating non-conductive materials that can obtain charge, sputtering with a PDC power supply may be effective. In some cases, sputtering technology can be detected under cross-sectional TEM / EELS / EDX.

[0100] Fig. 10A An example of a memory device 1000-a supporting a composite electrode material chemistry according to an example disclosed herein is shown. The memory device 1000-a may be a reference Figure 1 Memory device 1000-a includes access line 1005-a, which may be as shown in FIG. Figure 2 and 3The memory device 1000-a may also include an electrode 1010-a, an electrode 1025-a, and a memory element 1020-a, which may be examples of the electrode 325 and the memory element 320, respectively, as described in reference Figure 3 The memory device 1000 - a further includes an interface layer 1015 - a .

[0101] Memory device 1000-a can be manufactured by various combinations of material formation and removal. For example, material layers corresponding to access line 1005-a, electrode 1010-a, interface layer 1015-a, memory element 1020-a, and electrode 1025-a can be deposited. Materials can be selectively removed to produce desired features, such as Fig. 10A The column structure depicted.

[0102] The access line 1005-a may be made of tungsten, tungsten silicon nitride, or both. The electrode 1010-a may be coupled to the interface layer 1015-a and the access line 1005-a. In some cases, the electrode 1010-a may include a material including a tantalum-carbon compound, wherein the material may be operated to be chemically inert relative to the memory element 1020-a. The material may include a thermally stable resistivity and have a lower resistance to signals transmitted between the access line 1005-a and the memory element 1020-a across the operating temperature range of the memory element 1020-a compared to the resistance of the material without the tantalum-carbon compound. For example, the composition of the electrode material may prevent a chemical reaction from occurring between the electrode 1010-a and the memory element 1020-a.

[0103] The interface layer 1015-a can be coupled between the electrode 1010-a and the memory element 1020-a. In such cases, the interface layer 1015-a can operate to provide a lower resistance to signals transmitted between the access line 1005-a and the memory element 1020-a across an operating temperature range of the memory element 1020-a, compared to the resistance of a material without the tantalum-carbon compound. In some examples, the interface layer 1015-a can include carbon (e.g., without tantalum).

[0104] The memory element 1020-a can be positioned between the interface layer 1015-a and the electrode 1025-a. The memory element 1020-a can be an example of a self-selective memory component. For example, the memory element 1020-a can be an example of a storage element with a variable resistance. In such cases, the memory element 1020-a can include a metal oxide, a chalcogenide, etc. The chalcogenide material can be a material or alloy containing at least one of the elements sulfur (S), tellurium (Te), or Se. Many chalcogenide alloys are possible - for example, germanium-antimony (Sb)-tellurium alloy (Ge-Sb-Te) is a chalcogenide material. Other chalcogenide alloys not explicitly described herein can also be used.

[0105] Electrode 1025-a can be coupled to memory element 1020-a and an access line. In some examples, electrode 1025-a can be formed of carbon (e.g., without tantalum). In some cases, carbon can operate to be chemically inert relative to memory element 1020-a and provide a lower resistance to signals transmitted between access lines and memory element 1020-a across an operating temperature range of memory element 1020-a compared to the resistance of a material without a tantalum-carbon compound. For example, carbon can prevent a chemical reaction from occurring between electrode 1025-a and memory element 1020-a.

[0106] In some cases, a memory device 1000-a including an electrode 1010-a having a material including a tantalum-carbon compound and an electrode 1025-a having carbon can adjust the resistivity of the entire memory device 1000-a. In some cases, it may be beneficial for the electrode 1010-a to include a material including a tantalum-carbon compound, as opposed to the electrode 1025-a, because aging may include a higher impact on the bottom electrode (e.g., the electrode 1010-a). In such cases, the electrode 1010-a may include a resistivity lower than the resistivity of the electrode 1025-a to account for aging. In some cases, it may be preferred to have carbon adjacent to the memory element 1020-a (e.g., a combination of the interface layer 1015-a and the electrode 1025-a).

[0107] Fig. 10B An example of a memory device 1000-b supporting a composite electrode material chemistry according to an example disclosed herein is shown. The memory device 1000-b may be a reference Figure 1 and 10A Memory device 1000-b includes access line 1005-b, which may be an example of an access line, such as reference Figure 2 , 310A. The memory device 1000-b may also include an electrode 1010-b, an electrode 1025-b, and a memory element 1020-b, which may be examples of the electrode 325 and the memory element 320, respectively, as described in reference Figure 3 described.

[0108] The access line 1005-b may be made of tungsten, tungsten silicon nitride, or both. The electrode 1010-b may be coupled to the access line 1005-b and the memory element 1020-b. In some cases, the electrode 1010-b may include a material including a tantalum-carbon compound, wherein the material may be operable to be chemically inert relative to the memory element 1020-b. The material may include a thermally stable resistivity and have a lower resistance to signals transmitted between the access line 1005-b and the memory element 1020-b across the operating temperature range of the memory element 1020-b than the resistance of the material without the tantalum-carbon compound. For example, the electrode material may prevent a chemical reaction from occurring between the electrode 1010-b and the memory element 1020-b.

[0109] Memory element 1020-b may be positioned between electrode 1010-b and electrode 1025-b. Memory element 1020-b may be a reference Fig. 10A 1020-a. An electrode 1025-b can be coupled to the memory element 1020-b and the access line. In some examples, the electrode 1025-b can include carbon (e.g., without tantalum). In some cases, the carbon can operate to be chemically inert relative to the memory element 1020-b and provide a lower resistance to signals transmitted between the access line and the memory element 1020-b across the operating temperature range of the memory element 1020-b compared to the resistance of the material without the tantalum-carbon compound. For example, the carbon can prevent a chemical reaction from occurring between the electrode 1025-b and the memory element 1020-b.

[0110] In some cases, a memory device 1000-b including an electrode 1010-b having a material including a tantalum-carbon compound and an electrode 1025-b having carbon can adjust the resistivity of the entire memory device 1000-b. In some cases, it may be beneficial for electrode 1010-b to include a material including a tantalum-carbon compound as opposed to electrode 1025-b because aging may include a higher impact on the bottom electrode (e.g., electrode 1010-b). In such cases, electrode 1010-b may include a lower resistivity than the resistivity of electrode 1025-b to account for aging.

[0111] Fig. 10CAn example of a memory device 1000-c supporting a composite electrode material chemistry according to an example disclosed herein is shown. The memory device 1000-c may be a reference Figure 1 and 10A Memory device 1000-c includes access line 1005-c, which may be an example of an access line, such as reference Figure 2 , 3 10A. The memory device 1000-c may also include an electrode 1010-c, an electrode 1025-c, and a memory element 1020-c, which may be examples of the electrode 325 and the memory element 320, respectively, as described in reference Figure 3 The memory device 1000 - c also includes an interface layer 1015 - b .

[0112] The access line 1005-c may be made of tungsten, tungsten silicon nitride, or both. The electrode 1010-c may be coupled to the interface layer 1015-b and the access line 1005-c. In some cases, the electrode 1010-c may include a material including a tantalum-carbon compound, wherein the material may be operable to be chemically inert relative to the memory element 1020-c. The material may include a thermally stable resistivity and have a lower resistance to signals transmitted between the access line 1005-c and the memory element 1020-c across the operating temperature range of the memory element 1020-c than the resistance of the material without the tantalum-carbon compound. For example, the composition of the electrode material may prevent a chemical reaction from occurring between the electrode 1010-c and the memory element 1020-c.

[0113] The interface layer 1015-b can be coupled between the electrode 1010-c and the memory element 1020-c. In such cases, the interface layer 1015-b can operate to provide a lower resistance to signals transmitted between the access line 1005-c and the memory element 1020-c across the operating temperature range of the memory element 1020-c, compared to the resistance of the material without the tantalum-carbon compound. In some examples, the interface layer 1015-b can include carbon (e.g., without tantalum). In some cases, it may be preferred to have carbon adjacent to the memory element 1020-c (e.g., the composition of the interface layer 1015-b).

[0114] The memory element 1020-c may be positioned between the interface layer 1015-b and the electrode 1025-c. The memory element 1020-c may be a reference Fig. 10A1020-a. The electrode 1025-c can be coupled to the memory element 1020-c and the interface layer 1030-a. In some examples, the electrode 1025-c can include a material including a tantalum-carbon compound, wherein the material can be operated to be chemically inert relative to the memory element 1020-c. The material can include a thermally stable resistivity and have a lower resistance to signals transmitted between the access line and the memory element 1020-c across the operating temperature range of the memory element 1020-c than the resistance of the material without the tantalum-carbon compound. For example, the composition of the electrode material can prevent a chemical reaction from occurring between the electrode 1025-c and the memory element 1020-c.

[0115] In some examples, the memory device 1000-c can include an interface layer 1030-a. The interface layer 1030-a can be coupled between the electrode 1025-c and the access line. In such cases, the interface layer 1030-a can operate to provide a lower resistance to signals transmitted between the access line and the memory element 1020-c across an operating temperature range of the memory element 1020-c, compared to the resistance of a material without the tantalum-carbon compound. In some examples, the interface layer 1030-a can include carbon (e.g., without tantalum).

[0116] Fig. 10D An example of a memory device 1000-d supporting a composite electrode material chemistry according to an example disclosed herein is shown. The memory device 1000-d may be a reference Figure 1 and 10A Memory device 1000-d includes access line 1005-d, which may be an example of an access line, such as reference Figure 2 , 3 The memory device 1000-d may also include an electrode 1010-d, an electrode 1025-d, and a memory element 1020-d, which may be examples of the electrode 325 and the memory element 320, respectively, as described in reference to Figure 3 The memory device 1000 - d further includes an interface layer 1030 - b .

[0117] The access line 1005-d may be made of tungsten, tungsten silicon nitride, or both. The electrode 1010-d may be coupled to the access line 1005-d and the memory element 1020-d. In some cases, the electrode 1010-d may include a material including a tantalum-carbon compound, wherein the material may be operable to be chemically inert relative to the memory element 1020-d. The material may include a thermally stable resistivity and have a lower resistance to signals transmitted between the access line 1005-d and the memory element 1020-d across the operating temperature range of the memory element 1020-d compared to the resistance of the material without the tantalum-carbon compound. For example, the composition of the electrode material may prevent a chemical reaction from occurring between the electrode 1010-d and the memory element 1020-d.

[0118] Memory element 1020-d may be positioned between electrode 1010-d and electrode 1025-d. Memory element 1020-d may be a reference Fig. 10A 1020-a. An electrode 1025-d can be coupled to the memory element 1020-d and the interface layer 1030-b. In some examples, the electrode 1025-d can include a material including a tantalum-carbon compound, wherein the material can be operated to be chemically inert relative to the memory element 1020-d. The material can include a thermally stable resistivity and have a lower resistance to signals transmitted between the access line and the memory element 1020-d across the operating temperature range of the memory element 1020-d compared to the resistance of the material without the tantalum-carbon compound. For example, the composition of the electrode material can prevent a chemical reaction from occurring between the electrode 1025-d and the memory element 1020-d.

[0119] In some examples, memory device 1000-d can include interface layer 1030-b. Interface layer 1030-b can be coupled between electrode 1025-d and an access line. In such cases, interface layer 1030-b can operate to provide a lower resistance to signals transmitted between access line and memory element 1020-d across an operating temperature range of memory element 1020-d compared to the resistance of a material without the tantalum-carbon compound. In some examples, interface layer 1030-b can include carbon (e.g., without tantalum).

[0120] Fig. 10E An example of a memory device 1000-e supporting a composite electrode material chemistry according to an example disclosed herein is shown. The memory device 1000-e may be a reference Figure 1 and 10A Memory device 1000-e includes access line 1005-e, which may be an example of an access line, such as reference Figure 2 , 3The memory device 1000-e may also include an electrode 1010-e, an electrode 1025-e, and a memory element 1020-e, which may be examples of the electrode 325 and the memory element 320, respectively, as described in reference to Figure 3 The memory device 1000 - e further includes an interface layer 1030 - c .

[0121] The access line 1005-e can be made of tungsten, tungsten silicon nitride, or both. The electrode 1010-e can be coupled to the access line 1005-e and the memory element 1020-e. In some cases, the electrode 1010-e can include carbon (e.g., without tantalum). The carbon can operate to be chemically inert relative to the memory element 1020-e and provide a lower resistance to signals transmitted between the access line 1005-e and the memory element 1020-e across the operating temperature range of the memory element 1020-e compared to the resistance of the material without the tantalum-carbon compound. For example, the carbon can prevent a chemical reaction from occurring between the electrode 1010-e and the memory element 1020-e.

[0122] The memory element 1020-e may be positioned between the electrode 1010-e and the electrode 1025-e. The memory element 1020-e may be a reference Fig. 10A 1020-a. The electrode 1025-e may be coupled to the memory element 1020-e and the interface layer 1030-c. In some examples, the electrode 1025-e may include a material including a tantalum-carbon compound, wherein the material may be operated to be chemically inert relative to the memory element 1020-e. The material may include a thermally stable resistivity and have a lower resistance to signals transmitted between the access line and the memory element 1020-e across the operating temperature range of the memory element 1020-e compared to the resistance of the material without the tantalum-carbon compound. For example, the composition of the electrode material may prevent a chemical reaction from occurring between the electrode 1025-e and the memory element 1020-e. In some cases, a memory device 1000-e including an electrode 1025-e having a material including a tantalum-carbon compound and an electrode 1010-e having carbon may adjust the resistivity of the entire memory device 1000-e.

[0123] In some examples, the memory device 1000-e can include an interface layer 1030-c. The interface layer 1030-c can be coupled between the electrode 1025-e and the access line. In such cases, the interface layer 1030-c can operate to provide a lower resistance to signals transmitted between the access line and the memory element 1020-e across an operating temperature range of the memory element 1020-e, compared to the resistance of a material without the tantalum-carbon compound. In some examples, the interface layer 1030-c can include carbon (e.g., without tantalum).

[0124] Fig.10F An example of a memory device 1000-f supporting a composite electrode material chemistry according to an example disclosed herein is shown. The memory device 1000-f may be a reference Figure 1 and 10A Memory device 1000-f includes access line 1005-f, which may be an example of an access line, such as reference Figure 2 , 3 The memory device 1000-f may also include an electrode 1010-f, an electrode 1025-f, and a memory element 1020-f, which may be examples of the electrode 325 and the memory element 320, respectively, as described in reference to Figure 3 The memory device 1000 - f also includes an interface layer 1030 - d .

[0125] The access line 1005-f can be made of tungsten, tungsten silicon nitride, or both. The electrode 1010-f can be coupled to the access line 1005-f and the memory element 1020-f. In some cases, the electrode 1010-f can include carbon (e.g., without tantalum). The carbon can operate to be chemically inert relative to the memory element 1020-f and provide a lower resistance to signals transmitted between the access line 1005-f and the memory element 1020-f across the operating temperature range of the memory element 1020-f compared to the resistance of the material without the tantalum-carbon compound. For example, the carbon can prevent a chemical reaction from occurring between the electrode 1010-f and the memory element 1020-f.

[0126] Memory element 1020-f may be positioned between electrode 1010-f and electrode 1025-f. Memory element 1020-f may be a reference Fig. 10A1020-a. An electrode 1025-f can be coupled to the memory element 1020-f and the interface layer 1030-d. In some examples, the electrode 1025-f can include a material including a tantalum-carbon compound, wherein the material can be operated to be chemically inert relative to the memory element 1020-f. The material can include a thermally stable resistivity and have a lower resistance to signals transmitted between the access line and the memory element 1020-f across the operating temperature range of the memory element 1020-f than the resistance of the material without the tantalum-carbon compound. For example, the composition of the electrode material can prevent a chemical reaction from occurring between the electrode 1025-f and the memory element 1020-f.

[0127] In some cases, the material of the electrode 1025-f may also include carbon. For example, the electrode 1025-f may include a carbon gradient in which carbon is concentrated at the interface of the interface layer 1030-d and dispersed at the interface layer of the memory element 1020-f. For example, the material of the electrode 1025-f may include a mixture of pure carbon at the interface between the interface layers 1030 and pure carbon and tantalum-carbon compounds at the interface between the memory elements 1020-f. Compared to the electrode 1025-f containing only tantalum-carbon compounds or carbon, the composite electrode 1025-f composition of tantalum-carbon compounds and carbon can reduce resistivity. In such cases, the material of the electrode 1025-f can improve the aging efficiency and reliability of the memory device 1000-f by producing consistent thermal properties and spike current annealing effects.

[0128] In some examples, memory device 1000-f can include interface layer 1030-d. Interface layer 1030-d can be coupled between electrode 1025-f and an access line. In such cases, interface layer 1030-d can operate to provide a lower resistance to signals transmitted between access line and memory element 1020-f across an operating temperature range of memory element 1020-f compared to the resistance of a material without the tantalum-carbon compound. In some examples, interface layer 1030-d can include carbon (e.g., without tantalum).

[0129] Figure 10G An example of a memory device 1000-g supporting a composite electrode material chemistry according to an example disclosed herein is shown. The memory device 1000-g may be a reference Figure 1 and 10A Memory device 1000-g includes access line 1005-g, which may be an example of an access line, such as reference Figure 2 , 310A. The memory device 1000-b may also include an electrode 1010-g, an electrode 1025-g, and a memory element 1020-g, which may be examples of the electrode 325 and the memory element 320, respectively, as described in reference Figure 3 described.

[0130] The access line 1005-g may be made of tungsten, tungsten silicon nitride, or both. The electrode 1010-g may be coupled to the access line 1005-g and the memory element 1020-g. In some cases, the electrode 1010-g may include carbon (e.g., without tantalum). In some cases, the carbon may operate to be chemically inert relative to the memory element 1020-g and provide a lower resistance to signals transmitted between the access line 1005-g and the memory element 1020-g across the operating temperature range of the memory element 1020-g compared to the resistance of the material without the tantalum-carbon compound. For example, the carbon may prevent a chemical reaction from occurring between the electrode 1010-g and the memory element 1020-g.

[0131] Memory element 1020-g may be positioned between electrode 1010-g and electrode 1025-g. Memory element 1020-g may be a reference Fig. 10A 1020-a. The electrode 1025-g may be coupled to the memory element 1020-b and the access line. In some cases, the electrode 1025-g may include a material including a tantalum-carbon compound, wherein the material may be operated to be chemically inert relative to the memory element 1020-g. The material may include a thermally stable resistivity and have a lower resistance to signals transmitted between the access line and the memory element 1020-g across the operating temperature range of the memory element 1020-g compared to the resistance of the material without the tantalum-carbon compound. For example, the composition of the electrode material may prevent a chemical reaction from occurring between the electrode 1025-g and the memory element 1020-g. In some cases, a memory device 1000-g including an electrode 1010-g having carbon and an electrode 1025-g having a material including a tantalum-carbon compound may adjust the resistivity of the entire memory device 1000-g.

[0132] Fig. 10H An example of a memory device 1000-h supporting a composite electrode material chemistry according to an example disclosed herein is shown. The memory device 1000-h may be a reference Figure 1 and 10A Memory device 1000-h includes access line 1005-h, which may be an example of an access line, such as reference Figure 2 , 3and 10A. The memory device 1000-h may also include an electrode 1010-h, an electrode 1025-h, and a memory element 1020-h, which may be examples of the electrode 325 and the memory element 320, respectively, as described in reference Figure 3 described.

[0133] The access line 1005-h may be made of tungsten, tungsten silicon nitride, or both. The electrode 1010-h may be coupled to the access line 1005-h and the memory element 1020-h. In some cases, the electrode 1010-h may include a material including a tantalum-carbon compound, wherein the material may be operable to be chemically inert relative to the memory element 1020-h. The material may include a thermally stable resistivity and have a low resistance to signals transmitted between the access line 1005-h and the memory element 1020-h across the operating temperature range of the memory element 1020-h compared to the resistance of the material without the tantalum-carbon compound. For example, the composition of the electrode material may prevent a chemical reaction from occurring between the electrode 1010-h and the memory element 1020-h.

[0134] Memory element 1020-h may be positioned between electrode 1010-h and electrode 1025-h. Memory element 1020-h may be a reference Fig. 10A 1020-a. An electrode 1025-h can be coupled to the memory element 1020-h and the access line. In some examples, the electrode 1025-h can include a material including a tantalum-carbon compound, wherein the material can be operated to be chemically inert relative to the memory element 1020-h. The material can include a thermally stable resistivity and have a lower resistance to signals transmitted between the access line 1005-h and the memory element 1020-h across the operating temperature range of the memory element 1020-h compared to the resistance of the material without the tantalum-carbon compound. For example, the composition of the electrode material can prevent a chemical reaction from occurring between the electrode 1025-h and the memory element 1020-h.

[0135] In some cases, a memory device 1000-h including an electrode 1010-h having a material including a tantalum-carbon compound and an electrode 1025-h having a material including a tantalum-carbon compound can adjust the resistivity of the entire memory device 1000-h. In some cases, it may be beneficial for both the electrode 1010-h and the electrode 1025-h to include a material including a tantalum-carbon compound, as opposed to the electrode 1025-b or the electrode 1010-h.

[0136] Fig.10IAn example of a memory device 1000-i supporting a composite electrode material chemistry according to an example disclosed herein is shown. The memory device 1000-i may be a reference Figure 1 and 10A Memory device 1000-i includes access line 1005-i, which may be an example of an access line, such as reference Figure 2 , 3 The memory device 1000-i may also include an electrode 1010-i, an electrode 1025-i, and a memory element 1020-i, which may be examples of the electrode 325 and the memory element 320, respectively, as described in reference to Figure 3 The memory device 1000 - i further includes an interface layer 1015 - c and an interface layer 1030 - i.

[0137] The access line 1005-i may be made of tungsten, tungsten silicon nitride, or both. The electrode 1010-i may be coupled to the interface layer 1015-c and the access line 1005-i. In some cases, the electrode 1010-i may include a material including a tantalum-carbon compound that is operable to be chemically inert relative to the memory element 1020-i. The material may include a thermally stable resistivity and have a lower resistance to signals transmitted between the access line 1005-i and the memory element 1020-i across the operating temperature range of the memory element 1020-i compared to the resistance of the material without the tantalum-carbon compound. For example, the electrode material may prevent a chemical reaction from occurring between the electrode 1010-i and the memory element 1020-i.

[0138] The interface layer 1015-c can be coupled between the electrode 1010-i and the memory element 1020-i. In such cases, the interface layer 1015-c can operate to provide a lower resistance to signals transmitted between the access line 1005-i and the memory element 1020-i across the operating temperature range of the memory element 1020-i compared to the resistance of the material without the tantalum-carbon compound. In some examples, the interface layer 1015-c can include carbon (e.g., without tantalum). In some cases, it may be preferred to have carbon adjacent to the memory element 1020-i (e.g., the composition of the interface layer 1015-c).

[0139] Memory element 1020-i may be positioned between interface layer 1015-i and interface layer 1035-a. Memory element 1020-i may be a reference Fig. 10AAn example of a memory element 1020-a described herein. An interface layer 1035-a can be coupled between the electrode 1025-i and the memory element 1020-i. In such cases, the interface layer 1035-a can operate to provide a lower resistance to signals transmitted between the access line and the memory element 1020-i across an operating temperature range of the memory element 1020-i, compared to the resistance of a material without the tantalum-carbon compound. In some examples, the interface layer 1035-a can include carbon (e.g., without tantalum).

[0140] Electrode 1025-i can be coupled to interface layer 1035-a. In some examples, electrode 1025-i can include a material including a tantalum-carbon compound, wherein the material can operate to be chemically inert relative to memory element 1020-i and provide a lower resistance to signals transmitted between an access line and memory element 1020-i across an operating temperature range of memory element 1020-i. For example, the composition of the electrode material can prevent a chemical reaction from occurring between electrode 1025-i and memory element 1020-i.

[0141] Fig.10J An example of a memory device 1000-j supporting a composite electrode material chemistry according to an example disclosed herein is shown. The memory device 1000-j may be a reference Figure 1 and 10A Memory device 1000-j includes access line 1005-j, which may be an example of an access line, such as reference Figure 2 , 3 10A. The memory device 1000-j may also include an electrode 1010-j, an electrode 1025-j, and a memory element 1020-j, which may be examples of the electrode 325 and the memory element 320, respectively, as described in reference Figure 3 The memory device 1000 - j further includes an interface layer 1015 - d , an interface layer 1017 - a , an interface layer 1030 - e , and an interface layer 1035 - b .

[0142] Access line 1005-j may be made of tungsten, tungsten silicon nitride, or both. Interface layer 1017-a may be coupled to access line 1005-j. Electrode 1010-j may be coupled to interface layer 1015-d and interface layer 1017-a. Interface layer 1017-a may operate to provide a lower resistance to signals transmitted between access line 1005-j and memory element 1020-j across an operating temperature range of memory element 1020-j, compared to the resistance of a material without the tantalum-carbon compound. In some examples, interface layer 1017-a may include carbon (e.g., without tantalum).

[0143] In some cases, electrode 1010-j can include a material including a tantalum-carbon compound, wherein the material can be operated to be chemically inert relative to memory element 1020-j. The material can include a thermally stable resistivity and have a lower resistance to signals transmitted between access line 1005-j and memory element 1020-j across an operating temperature range of memory element 1020-j, compared to the resistance of the material without the tantalum-carbon compound. For example, the composition of the electrode material can prevent a chemical reaction from occurring between electrode 1010-j and memory element 1020-j.

[0144] The interface layer 1015-d can be coupled between the electrode 1010-j and the memory element 1020-j. In such cases, the interface layer 1015-d can operate to provide a lower resistance to signals transmitted between the access line 1005-j and the memory element 1020-j across the operating temperature range of the memory element 1020-j, compared to the resistance of the material without the tantalum-carbon compound. In some examples, the interface layer 1015-d can include carbon (e.g., without tantalum). In some cases, it may be preferred to have carbon adjacent to the memory element 1020-j (e.g., the composition of the interface layer 1015-d).

[0145] Memory element 1020-j may be positioned between interface layer 1015-d and interface layer 1035-b. Memory element 1020-j may be a reference Fig. 10A 1020-a. An interface layer 1035-b can be coupled between the electrode 1025-j and the memory element 1020-j. In such cases, the interface layer 1035-b can operate to provide a lower resistance to signals transmitted between the access line and the memory element 1020-j across the operating temperature range of the memory element 1020-j, compared to the resistance of the material without the tantalum-carbon compound. In some examples, the interface layer 1035-b can include carbon (e.g., without tantalum).

[0146] Electrode 1025-j can be coupled to interface layer 1035-b and interface layer 1030-e. In some examples, electrode 1025-j can be a material including a tantalum-carbon compound, wherein the material can be operated to be chemically inert relative to memory element 1020-j. The material can include a thermally stable resistivity and have a lower resistance to signals transmitted between an access line and memory element 1020-j across an operating temperature range of memory element 1020-j compared to the resistance of the material without the tantalum-carbon compound. For example, the composition of the electrode material can prevent a chemical reaction from occurring between electrode 1025-j and memory element 1020-j.

[0147] In some examples, the memory device 1000-j can include an interface layer 1030-e. The interface layer 1030-e can be coupled between the electrode 1025-j and the access line. In such cases, the interface layer 1030-e can operate to provide a lower resistance to signals transmitted between the access line and the memory element 1020-j across an operating temperature range of the memory element 1020-jv, compared to the resistance of a material without the tantalum-carbon compound. In some examples, the interface layer 1030-e can include carbon (e.g., without tantalum).

[0148] Figures 10A-10J Various electrode configurations of memory cells are shown, including different configurations of top electrodes and bottom electrodes. Some electrode configurations also include one or more interfaces. Some electrode interfaces may include a composition having a material gradient from a first end to a second end, such that the composition of carbon and tantalum at the first end is different from the composition of carbon and tantalum at the second end. Any electrode configuration in the electrode configuration (whether top electrode or bottom electrode) can be combined to form a column of a memory cell. The present disclosure is not limited to the explicit column configuration shown. Additionally or alternatively, any electrode configuration in the electrode configuration can be rotated or changed. In some cases, using a configuration of a bottom electrode shown for a top electrode may cause the structure to rotate or flip relative to the configuration shown.

[0149] Fig.11 A flow chart is shown, which illustrates one or more methods 1100 of supporting composite electrode material chemistry according to examples disclosed herein. The operation of method 1100 can be implemented by a manufacturing system or one or more controllers associated with a manufacturing system. In some examples, one or more controllers can execute a set of instructions to control one or more functional elements of a manufacturing system to perform the described functions. Additionally or alternatively, one or more controllers can use dedicated hardware to perform various aspects of the described functions.

[0150] At 1105, method 1100 can include sputtering a tantalum-carbon compound composition with a first sputtering target. The operation of 1105 can be performed according to the methods described herein.

[0151] At 1110, method 1100 may include forming an electrode including a composition of a first material doped with a second material, the second material including a composition of a tantalum-carbon compound, the second material operable to be chemically inert with respect to a memory element including a chalcogenide of the memory element, the second material including a thermally stable resistivity compared to the resistance of the first material and having a lower resistance to signals transmitted between an access line and the memory element across an operating temperature range of the memory element including the chalcogenide. The operations of 1110 may be performed according to methods described herein.

[0152] In some examples, method 1100 may include features, components, or instructions (e.g., a non-transitory computer-readable medium storing instructions executable by a processor) for: sputtering a composition of a tantalum-carbon compound with a first sputtering target; and forming an electrode comprising a composition of a first material doped with a second material, the second material comprising a composition of a tantalum-carbon compound, the second material being operable to be chemically inert relative to a memory element comprising a chalcogenide of the memory element, the second material comprising a thermally stable resistivity and having a lower resistance to signals transmitted between an access line and the memory element across an operating temperature range of the memory element comprising the chalcogenide compared to the resistance of the first material.

[0153] In some examples, sputtering the composition of tantalum-carbon compound can further include operations, features, components, or instructions for depositing carbon on the substrate and depositing tantalum on the substrate simultaneously with the carbon. Some examples of method 1100 can further include operations, features, components, or instructions for sputtering carbon with a second sputtering target different from the first sputtering target, wherein the first material of the composition of the electrode includes carbon.

[0154] In some examples of method 1100, sputtering the composition of tantalum-carbon compound includes depositing the composition with a first sputtering target at a first power density, and sputtering carbon includes depositing carbon with a second sputtering target at a second power density different from the first power density. Some examples of method 1100 may further include operations, features, components, or instructions for applying a PVD process to a provided substrate to control bond formation between carbon and the composition of tantalum-carbon compound.

[0155] In some examples of method 1100, the first sputtering target can be powered by a DC power supply. In some examples of method 1100, the first sputtering target can be powered by a pulsed DC power supply, wherein the pulsed DC power supply can be configured to adjust the frequency of depositing the tantalum-carbon compound composition. It should be noted that the methods described herein are possible embodiments, and operations or steps can be rearranged or otherwise modified, and other embodiments are possible. In addition, portions of two or more of the methods can be combined.

[0156] A device is described. The device may include: an access line; a memory element including a storage element including a chalcogenide; and an electrode coupled to the memory element and the access line and including a composition doped with a first material, the second material including a tantalum-carbon compound, the second material operable to be chemically inert relative to the storage element of the memory element, the second material including a thermally stable resistivity and having a lower resistance to signals transmitted between the access line and the memory element across an operating temperature range of the storage element compared to the resistance of the first material.

[0157] In some examples, the resistivity of the composition of the electrode across the operating temperature range of the storage element can be in the range of 0.1-10 mohm-cm. In some examples, the first material comprises carbon. In some examples, the first material comprises carbon and tantalum. In some examples, the amount of tantalum-carbon compound can be less than or equal to 10 at.% of the composition. In some examples, the amount of tantalum can be equal to 3.2 at.% of the composition. In some examples, the amount of tantalum can be equal to 3.4 at.% of the composition. In some examples, the amount of tantalum-carbon compound can be less than or equal to 94.8 at.% of the composition.

[0158] Some instances of the device can include a second electrode coupled to the memory element and the access line and comprising a composition of a third material doped with a fourth material, the fourth material comprising carbon, the tantalum-carbon compound, or both, the fourth material operable to be chemically inert relative to the memory element comprising the chalcogenide of the memory element, the fourth material comprising a thermally stable resistivity compared to the resistance of the third material and having a lower resistance to signals transmitted between the access line and the memory element across the operating temperature range of the memory element.

[0159] Some examples of the device can include an interface layer coupled to the electrode and including carbon, the interface layer operable to provide a lower resistance to signals transmitted between the access line and the memory element across the operating temperature range of the memory element compared to the resistance of the first material. In some examples, the interface layer can be coupled between the memory element and the electrode. In some examples, the interface layer can be coupled between the memory element and the access line.

[0160] A device is described. The device may include: a memory element including a storage element including a chalcogenide; a first electrode coupled to the memory element and a first access line and including a composition of a first material doped with a second material, the second material including a tantalum-carbon compound, the second material operable to be chemically inert relative to the storage element of the memory element, the second material including a thermally stable resistivity compared to a resistance of the first material and having a lower resistance to signals transmitted between the first access line and the memory element across an operating temperature range of the memory element; and a second electrode coupled to the memory element and a second access line and including a composition of a third material doped with a fourth material including carbon, the fourth material operable to be chemically inert relative to the storage element of the memory element, the fourth material including a thermally stable resistivity compared to a resistance of the third material and having a lower resistance to signals transmitted between the second access line and the memory element across an operating temperature range of the memory element.

[0161] The information and signals described herein may be represented using any of a variety of different processes and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof. Some of the figures may show a signal as a single signal; however, one of ordinary skill in the art will appreciate that a signal may represent a signal bus, where the bus may have various bit widths.

[0162] The terms "electronic communication," "conductive contact," "connection," and "coupling" may refer to a relationship between components that supports the flow of electrons between the components. Components are considered to be in electronic communication with each other (or in conductive contact, connected, or coupled to each other) if there is any conductive path between the components that can support the flow of signals between the components at any time. At any given time, based on the operation of the device containing the connected components, the conductive path between the components that are in electronic communication with each other (or in conductive contact or connected or coupled to each other) may be an open circuit or a closed circuit. The conductive path between the connected components may be a direct conductive path between the components, or the conductive path between the connected components may be an indirect conductive path that may include intermediate components, such as switches, transistors, or other components. In some instances, the signal flow between the connected components may be interrupted for a period of time, for example, using one or more intermediate components (such as switches or transistors).

[0163] As used herein, the term "layer" or "level" refers to a stratum or sheet of a geometric structure (e.g., relative to a substrate). Each layer or level can have three dimensions (e.g., height, width, and depth) and can cover at least a portion of a surface. For example, a layer or level can be a three-dimensional structure in which two dimensions are greater than the third dimension, e.g., a thin film. A layer or level can contain different elements, components, and / or materials. In some instances, a layer or level may be composed of two or more sub-layers or sub-levels.

[0164] As used herein, the term "electrode" may refer to an electrical conductor and, in some instances, may be used as an electrical contact to a memory cell or other component of a memory array. An electrode may include a trace, a wire, a conductive line, a conductive layer, etc., that provides a conductive path between elements or components of a memory array.

[0165] The devices including memory arrays discussed herein may be formed on a semiconductor substrate such as silicon, germanium, silicon-germanium alloys, gallium arsenide, gallium nitride, etc. In some instances, the substrate is a semiconductor wafer. In other instances, the substrate may be a silicon-on-insulator (SOI) substrate such as silicon-on-glass (SOG) or silicon-on-sapphire (SOS) or an epitaxial semiconductor material layer on another substrate. The conductivity of the substrate or a sub-region of the substrate may be controlled by doping with various chemicals including but not limited to phosphorus, boron, or arsenic. Doping may be performed by ion implantation during the initial formation or growth of the substrate or by any other doping means.

[0166] The chalcogenide material may be a material or alloy containing at least one of the elements S, Se and Te. The phase change material discussed herein may be a chalcogenide material. The chalcogenide material may include an alloy of S, Se, Te, Ge, As, Al, Sb, Au, indium (In), gallium (Ga), tin (Sn), bismuth (Bi), palladium (Pd), cobalt (Co), oxygen (O), silver (Ag), nickel (Ni), platinum (Pt). Example chalcogenide materials and alloys may include, but are not limited to: Ge-Te, In-Se, Sb-Te, Ga-Sb, In-Sb, As-Te, Al-Te, Ge-Sb-Te, Te-Ge- As, In-Sb-Te, Te-Sn-Se, Ge-Se-Ga, Bi-Se-Sb, Ga-Se-Te, Sn-Sb-Te, In-Sb-Ge, Te-Ge-Sb-S, Te-Ge-Sn-O, Te-Ge-Sn-Au, Pd-Te-Ge-Sn, In-Se-Ti-Co, Ge-Sb-Te-Pd, Ge-Sb-Te-Co, Sb-Te- Bi-Se, Ag-In-Sb-Te, Ge-Sb-Se-Te, Ge-Sn-Sb-Te, Ge-Te-Sn-Ni, Ge-Te-Sn-Pd or Ge-Te-Sn-Pt. As used herein, chemical composition symbols connected by hyphens indicate the elements contained in a particular compound or alloy and are intended to represent all stoichiometric amounts containing the indicated elements. For example, Ge-Te may contain Ge x Te y , where x and y can be any positive integer. Other examples of variable resistance materials can include binary metal oxide materials or mixed valence oxides including two or more metals, such as transition metals, alkaline earth metals, and / or rare earth metals. Embodiments are not limited to specific variable resistance materials or materials associated with memory elements of memory cells. For example, other examples of variable resistance materials can be used to form memory elements and can include chalcogenide materials, giant magnetoresistive materials, or polymer-based materials, etc.

[0167] The transistor discussed herein may represent a field effect transistor (FET) and may include a three-terminal device including a source, a drain and a gate. The terminals may be connected to other electronic components by conductive materials such as metals. The source and drain may be conductive and may include heavily doped, for example, degenerate semiconductor regions. The source and drain may be separated by a lightly doped semiconductor region or a channel. If the channel is n-type (i.e., most carriers are electrons), the FET may be referred to as an n-type FET. If the channel is p-type (i.e., most carriers are holes), the FET may be referred to as a p-type FET. The channel may be capped by an insulating gate oxide. Channel conductivity may be controlled by applying a voltage to the gate. For example, applying a positive voltage or a negative voltage to an n-type FET or a p-type FET, respectively, may make the channel conductive. When a voltage greater than or equal to the threshold voltage of the transistor is applied to the transistor gate, the transistor may be "turned on" or "activated". When a voltage less than or equal to the threshold voltage of the transistor is applied to the transistor gate, the transistor may be "turned off" or "deactivated".

[0168] The description set forth herein describes example configurations in conjunction with the accompanying drawings and does not represent all instances that may be implemented within the scope of the claims or that are within the scope of the claims. The term "exemplary" as used herein means "serving as an example (example / instance) or illustration", rather than "preferred" or "better than other instances". The detailed description contains specific details for providing an understanding of the described techniques. However, these techniques may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described instances.

[0169] In the accompanying drawings, similar components or features may have the same reference number. Further, various components of the same type may be distinguished by following the reference number with a dash and a second reference number that distinguishes the similar components. If only the first reference number is used in the specification, the description applies to any component in the similar components having the same first reference number, regardless of the second reference number.

[0170] The information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0171] The various illustrative blocks and modules described in conjunction with the disclosure herein may be implemented or performed with a general purpose processor, a DSP, an ASIC, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0172] The functions described herein can be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the function can be stored in a computer-readable medium in the form of one or more instructions or codes or transmitted by a computer-readable medium. Other examples and embodiments are within the scope of the present disclosure and the appended claims. For example, due to the nature of the software, the above functions can be implemented using software, hardware, firmware, hard wiring, or any combination thereof executed by a server. The features of the implementation functions can also be physically located at various locations, and the various locations include being distributed so that the various parts of the functions are implemented at different physical locations. And, as used herein (included in the claims), as used in a list of items (e.g., a list of items ending with phrases such as "at least one of ..." or "one or more of ..."), "or" indicates an inclusive list, so that, for example, at least one of the lists A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). And, as used herein, the phrase "based on" should not be interpreted as a reference to a conditional closed set. For example, without departing from the scope of the present disclosure, the exemplary steps described as "based on condition A" may be based on both condition A and condition B. In other words, as used herein, the phrase "based on" should be interpreted in the same manner as the phrase "based at least in part on."

[0173] Computer-readable media includes non-transitory computer storage media and communication media including any media that promotes the transmission of computer programs from one place to another.Non-transitory storage media can be any available media that can be accessed by a general-purpose computer or a special-purpose computer.By way of example and not limitation, non-transitory computer-readable media can include RAM, ROM, electrically erasable programmable read-only memory (EEPROM), compact disk (CD) ROM or other optical disk storage device, magnetic disk storage device or other magnetic storage device or can be used for carrying or storing desired program code devices in the form of instructions or data structures and can be accessed by a general-purpose computer or a special-purpose computer or a general-purpose processor or a special-purpose processor.And, any connection is appropriately referred to as computer-readable media.For example, if coaxial cable, optical fiber cable, twisted pair, digital subscriber line (DSL) or wireless technologies such as infrared, radio and microwave are used to transmit software from a website, a server or other remote source, the coaxial cable, optical fiber cable, twisted pair, digital subscriber line (DSL) or wireless technologies such as infrared, radio and microwave are included in the definition of media. Disk or disc as used herein includes CD, laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc, where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.

[0174] The description herein is provided to enable those skilled in the art to make or use the present disclosure. Various modifications to the present disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the scope of the present disclosure. Therefore, the present disclosure is not limited to the examples and designs described herein, but is intended to conform to the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. A memory device, comprising: Access line; a memory element, the memory element comprising a memory element including a chalcogenide; as well as An electrode coupled to the memory element and the access line and comprising a composition of a first material doped with a second material, the second material comprising a tantalum-carbon compound, the second material operable to be chemically inert relative to the memory element of the memory element, the second material comprising a thermally stable resistivity compared to the resistance of the first material and having a lower resistance to signals transmitted between the access line and the memory element across an operating temperature range of the memory element, wherein the first material comprises carbon or the first material comprises carbon and tantalum.

2. The memory device of claim 1, wherein the composition of the electrode has a resistivity in the range of 0.1-10 mohm-cm across the operating temperature range of the storage element.

3. The memory device of claim 1, wherein the amount of the tantalum-carbon compound is less than or equal to 10 atomic percent at. % of the composition.

4. The memory device of claim 1, wherein the amount of tantalum is equal to 3.2 at. % of the composition.

5. The memory device of claim 1, wherein the amount of tantalum is equal to 3.4 at. % of the composition.

6. The memory device of claim 1, wherein an amount of the tantalum-carbon compound is less than or equal to 94.8 at. % of the composition.

7. The memory device of claim 1, further comprising: a second electrode coupled to the memory element and the access line and comprising a composition of a third material doped with a fourth material, the fourth material comprising carbon, the tantalum-carbon compound, or both, the fourth material operable to be chemically inert relative to the memory element comprising the chalcogenide of the memory element, the fourth material comprising a thermally stable resistivity compared to the resistance of the third material and having a lower resistance to signals transmitted between the access line and the memory element across the operating temperature range of the memory element, wherein the third material comprises carbon or the third material comprises carbon and tantalum.

8. The memory device of claim 1, further comprising: An interfacial layer coupled to the electrode and comprising carbon, the interfacial layer being operable to provide a lower resistance to signals transmitted between the access line and the memory element across the operating temperature range of the memory element compared to the resistance of the first material.

9. The memory device of claim 8, wherein the interface layer is coupled between the memory element and the electrode.

10. The memory device of claim 8, wherein the interface layer is coupled between the memory element and the access line.

11. A method of forming a memory device, comprising: sputtering a tantalum-carbon compound composition using a first sputtering target; as well as An electrode is formed, the electrode comprising a composition of a first material doped with a second material, the second material comprising the composition of the tantalum-carbon compound, the second material being operable to be chemically inert relative to a memory element comprising a chalcogenide of the memory element, the second material comprising a thermally stable resistivity compared to the resistance of the first material and having a lower resistance to signals transmitted between an access line and the memory element across an operating temperature range of the memory element comprising the chalcogenide, wherein the first material comprises carbon or the first material comprises carbon and tantalum.

12. The method of claim 11, wherein sputtering the composition of the tantalum-carbon compound further comprises: depositing carbon on a substrate; as well as Tantalum is deposited on the substrate simultaneously with the deposition of the carbon.

13. The method according to claim 11, further comprising: Carbon is sputtered with a second sputtering target different from the first sputtering target, wherein the first material of the composition of the electrode includes the carbon.

14. The method of claim 13, wherein sputtering the composition of the tantalum-carbon compound comprises a first power density for depositing the composition with the first sputtering target, and wherein sputtering the carbon comprises a second power density for depositing the carbon with the second sputtering target that is different from the first power density.

15. The method according to claim 13, further comprising: A physical vapor deposition (PVD) process is applied to a substrate configured to control bond formation between the carbon and the composition of the tantalum-carbon compound.

16. The method of claim 15, wherein the first sputtering target is powered by a DC power supply.

17. The method of claim 15, wherein the first sputtering target is powered by a pulsed DC power supply, wherein the pulsed DC power supply is configured to adjust a frequency at which the composition of the tantalum-carbon compound is deposited.

18. A memory device comprising: a memory element, the memory element comprising a memory element including a chalcogenide; a first electrode coupled to the memory element and a first access line and comprising a composition of a first material doped with a second material, the second material comprising a tantalum-carbon compound, the second material operable to be chemically inert relative to the memory element of the memory element, the second material comprising a thermally stable resistivity compared to the resistance of the first material and having a lower resistance to signals transmitted between the first access line and the memory element across an operating temperature range of the memory element, wherein the first material comprises carbon or the first material comprises carbon and tantalum; as well as a second electrode coupled to the memory element and a second access line and comprising a composition of a third material doped with a fourth material comprising carbon, the fourth material operable to be chemically inert relative to the memory element of the memory element, the fourth material comprising a thermally stable resistivity compared to the resistance of the third material and having a lower resistance to signals transmitted between the second access line and the memory element across the operating temperature range of the memory element, wherein the third material comprises carbon or the third material comprises carbon and tantalum.

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