SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD OF THE SEMICONDUCTOR DEVICE
20230101919 · 2023-03-30
Assignee
Inventors
Cpc classification
H10B43/23
ELECTRICITY
H10B43/27
ELECTRICITY
International classification
H10B43/23
ELECTRICITY
H10B43/27
ELECTRICITY
Abstract
A semiconductor device and a method of manufacturing the semiconductor device are provided. The semiconductor device includes a source structure formed on a base, an etch prevention layer formed on the source structure, bit lines, a stack structure located between the etch prevention layer and the bit lines and including conductive layers and insulating layers that are alternately stacked on each other; and a source contact structure extending into the stack structure in a vertical direction to be coupled to the source structure, wherein the source contact structure includes polysilicon.
Claims
1. A semiconductor device, comprising: a source structure formed over a base; an etch prevention layer formed over the source structure; bit lines; a stack structure located between the etch prevention layer and the bit lines and including conductive layers and insulating layers that are alternately stacked on each other; and a source contact structure extending into the stack structure in a vertical direction to be coupled to the source structure, wherein the source contact structure includes polysilicon.
2. The semiconductor device of claim 1, wherein the polysilicon includes a dopant.
3. The semiconductor device of claim 2, wherein the source contact structure includes the dopant of one of an N-type and a P-type.
4. The semiconductor device of claim 1, further comprising a source contact pad disposed over the source contact structure.
5. The semiconductor device of claim 4, wherein the source contact pad includes a polysilicon layer including a dopant of one of an N-type and a P-type.
6. The semiconductor device of claim 5, wherein the source contact structure and the source contact pad include a same dopant.
7. The semiconductor device of claim 1, wherein the source structure includes a polysilicon layer including a dopant of one of an N-type and a P-type.
8. The semiconductor device of claim 7, wherein a type of the dopant included in the source structure is the same as or different from a type of a dopant included in the source contact structure.
9. The semiconductor device of claim 1, further comprising a barrier layer surrounding a sidewall of the source contact structure.
10. The semiconductor device of claim 9, wherein the barrier layer is a Ti/TiN layer.
11. The semiconductor device of claim 1, further comprising a slit passing through the stack structure and the etch prevention layer, wherein the source contact structure is disposed in the slit.
12. The semiconductor device of claim 11, further comprising a spacer filling the slit and surrounding a sidewall of the source contact structure.
13. The semiconductor device of claim 1, further comprising a channel structure extending into and disposed in the stack structure in the vertical direction, the channel structure extending into the source structure.
14. The semiconductor device of claim 13, wherein the source structure comprises: a first source layer formed over the base; and a second source layer located between the first source layer and the etch prevention layer and in direct contact with a lower portion of the channel structure.
15. The semiconductor device of claim 1, wherein the etch prevention layer includes silicon carbonitride (SiCN).
16. A method of manufacturing a semiconductor device, the method comprising: forming a first source layer over a base; forming a sacrificial layer over the first source layer; forming an etch prevention layer over the sacrificial layer; forming a stack structure including first material layers and second material layers that are alternately stacked on each other over the etch prevention layer; forming a channel structure passing through the stack structure, the etch prevention layer, and the sacrificial layer and extending into the first source layer; forming a slit passing through the stack structure and the etch prevention layer and exposing the sacrificial layer; forming a second source layer directly coupled to the channel structure by removing the sacrificial layer exposed through the slit and filling a space from which the sacrificial layer is removed with a conductive material; and forming a source contact structure including a dopant in the slit.
17. The method of claim 16, wherein the source contact structure includes a polysilicon layer including the dopant of one of an N-type and a P-type.
18. The method of claim 17, wherein the second source layer includes the conductive material including a dopant of a same type as the dopant of the source contact structure or the conductive material including a dopant of a different type from the dopant of the source contact structure.
19. The method of claim 16, further comprising, after forming a recess region by etching an upper portion of the source contact structure by a predetermined thickness, forming a source contact pad in the recess region.
20. The method of claim 19, wherein the source contact pad includes a dopant of a same type as the dopant of the source contact structure or a dopant of a different type from the dopant of the source contact structure.
21. The method of claim 16, further comprising, after forming the second source layer, forming a barrier layer on a sidewall of the slit.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0010]
[0011]
[0012]
[0013]
[0014]
[0015]
DETAILED DESCRIPTION
[0016] Hereinafter, various embodiments are described with reference to the accompanying drawings. In the drawings, thicknesses and distances of components may be exaggerated compared to the actual physical thicknesses and distances for convenience of illustration. In the following description, a description of known related functions and constitutions may be omitted for simplicity and conciseness. Like reference numerals refer to like elements throughout the specification and drawings.
[0017] It is also noted that in this specification, “connected/coupled” refers to one component not only directly connected/coupled to another component but also indirectly connected/coupled to another component through an intervening component. When an element is referred to as being “directly on,” “directly connected to” or “directly coupled to” another element or layer, there are no intervening elements or layers present. It is also understood that when a layer is referred to as being “on” another layer or substrate, it can be directly on the other or substrate, or intervening layers may also be present. In the specification, when an element is referred to as “comprising” or “including” a component, it does not exclude the inclusion of other additional components unless a description to the contrary is specifically pointed out in context.
[0018] Various embodiments may be directed to a semiconductor device with improved electrical characteristics and a method of manufacturing the semiconductor device.
[0019]
[0020] Referring to
[0021] The source structure S may be a conductive layer including polysilicon, metal, or the like, and may be a single layer or a multilayer film. The source structure S may be located between a base 10 and the stack structure ST. The base 10 may be a semiconductor substrate, an insulating layer, or the like.
[0022] The source structure S may include a first source layer 11A and a second source layer 11B. The first source layer 11A may be located adjacent to the base 10 and the second source layer 11B may be located adjacent to the stack structure ST. The second source layer 11B may be in physical contact with a sidewall of a lower portion of the channel structure CH, and more specifically, may be in direct contact with a channel layer 15 of the lower portion of the channel structure CH. The first source layer 11A may be in contact with the lower portion of the channel structure CH, and more specifically, may be in direct contact with a memory layer 16 of the lower portion of the channel structure CH. The second source layer 11B may include a polysilicon layer including an N-type or P-type dopant.
[0023] The stack structure ST may be located between the source structure S and the bit lines BL. The stack structure ST may include conductive layers 13 and insulating layers 14 alternately stacked on each other. The conductive layers 13 may be select lines, word lines, or the like. The insulating layers 14 may be provided to insulate the stacked conductive layers 13 from each other and may include an insulating material such as an oxide or a nitride.
[0024] The etch prevention layer 12 may be located in an interface between the source structure S and the stack structure ST. The etch prevention layer 12 may include silicon carbonitride (SiCN). The etch prevention layer 12 may prevent the stack structure ST from being etched during an etching process for exposing the channel layer 15 of the lower portion of the channel structure CH.
[0025] The channel structure CH may be coupled between the bit lines BL and the source structure S. The channel structure CH may pass through the stack structure ST and extend into the source structure S. The channel structure CH may include the channel layer 15, and may further include at least one of the memory layer 16 and a gap-fill layer 17. The channel layer 15 located in the lower portion of the channel structure CH may be physically coupled to the source structure S through the sidewall thereof. For example, the channel layer 15 located in the lower portion of the channel structure CH may be physically coupled to the second source layer 11B through the sidewall of the channel layer 15. The channel layer 15 may include a semiconductor material such as silicon (Si) or germanium (Ge). The memory layer 16 may surround the sidewall of the channel layer 15. The memory layer 16 may include at least one of a charge blocking layer 16A, a data storage layer 16B, and a tunnel insulating layer 16C. The data storage layer 16B may include a floating gate, a charge trapping material, polysilicon, a nitride, a variable resistance material, a phase-change material, nanodots, or the like. The gap-fill layer 17 may be formed in the channel layer 15. The gap-fill layer 17 may include an oxide layer.
[0026] A select transistor or a memory cell may be located in each of intersections of the channel structure CH and the conductive layers 13. A select transistor and a memory cell sharing the single channel layer 15 may form a single memory string. The memory string may include at least one drain select transistor, a plurality of memory cells, and at least one source select transistor coupled in series with each other.
[0027] The source contact structure 19 may pass through the stack structure ST to be coupled to the source structure S. The source contact structure 19 may be a conductive layer including polysilicon, metal, or the like. For example, the source contact structure 19 may be a polysilicon layer including an N-type or P-type dopant. A type of the dopant included in the source contact structure 19 may be the same as or different from a type of the dopant included in the second source layer 11B. A barrier layer BA may be disposed on a sidewall of the source contact structure 19. The barrier layer BA may include a Ti/TiN layer. A source contact pad S_PAD may be disposed over the source contact structure 19. The source contact pad S_PAD may include a polysilicon layer including an N-type or P-type dopant. A type of the dopant included in the source contact pad S_PAD may be the same as or different from the type of the dopant included in the source contact structure 19.
[0028] The spacer 18 may be interposed between the source contact structure 19 and the stack structure ST. The spacer 18 may be formed on the inner wall of the slit SL and may surround the sidewall of the source contact structure 19. The spacer 18 may include an insulating layer and may be a single layer or a multilayer film.
[0029] Referring to
[0030] The first source layer 11A and the second source layer 11B may include a conductive layer such as a polysilicon layer, and may include an N-type or P-type dopant. For example, when an erase operation is performed by a Gate Induced Drain Leakage (GIDL) method, the first source layer 11A and the second source layer 11B may include an N-type dopant such as phosphorus (P).
[0031] The etch prevention layer 12 may be interposed in an interface between the second source layer 11B and the stack structure ST. The etch prevention layer 12 may include silicon carbonitride (SiCN). The etch prevention layer 12 may prevent the stack structure ST from being etched during an etching process for exposing the channel layer 15 of the lower portion of the channel structure CH. Accordingly, the thickness of the lowermost insulating layer 14 of the stack structure ST may be reduced. Accordingly, a distance d between the source structure S and the conductive layer 13 that serves as a select transistor may be reduced. Thus, a distance by which impurities doped to the source structure S diffuse may be minimized and a junction overlap region may be easily formed, such that a Gate Induced Drain Leakage (GIDL) current may be stably generated during an erase operation. In addition, off characteristics of the select transistor may be improved, such that the semiconductor device may be designed to minimize the number of select transistors to be disposed and the integration density of the semiconductor device may also be improved.
[0032] The channel structure CH may pass through the stack structure (i.e., conductive layers 13 and insulating layers 14) and the etch prevention layer 12 and extend into the source structure S. For example, the lower portion of the channel structure CH may pass through the second source layer 11B and penetrate the first source layer 11A by a predetermined thickness.
[0033] A select transistor or a memory cell may be located in each of intersections of the channel structure CH and the conductive layers 13. A select transistor and a memory cell sharing the single channel layer 15 may form a single memory string. A memory string may include at least one drain select transistor, a plurality of memory cells, and at least one source select transistor coupled in series with each other.
[0034] The spacer 18 may be a multilayer film including a first spacer 18A and a second spacer 18B. The first spacer 18A may include a material having a different etch rate from the second spacer 18B. For example, the first spacer 18A may include an oxide layer and the second spacer 18B may include a nitride layer. A thickness of the second spacer 18B may be smaller than a thickness of the first spacer 18A. The second spacer 18B may be interposed between the first spacer 18A and the source contact structure 19.
[0035] The semiconductor device may further include memory layers 19A. The memory layers 19A may be interposed between the conductive layers 13 and the insulating layers 14 and between the conductive layers 13 and the channel structure CH.
[0036]
[0037] Referring to
[0038] Subsequently, an upper portion of the sacrificial layer 23 may be planarized by performing a planarization process and an etch prevention layer 24 may be formed on the sacrificial layer 23. The etch prevention layer 24 may include silicon carbonitride (SiCN).
[0039] Referring to
[0040] Subsequently, the channel structures CH passing through the stack structure ST, the etch prevention layer 24, the sacrificial layer 23, the buffer layer 22, and the first source layer 21 may be formed. The channel structures CH may pass through the first source layer 21 to be in contact with the base 20 or may penetrate a part of the first source layer 21 by a predetermined thickness, such that the bottom surfaces of the channel structures CH may be located in the first source layer 21.
[0041] A method of forming the channel structures CH is as below. First, channel holes passing through the stack structure ST, the etch prevention layer 24, the sacrificial layer 23, and the buffer layer 22 and penetrating a part of the first source layer 21 by at least a predetermined thickness may be formed. Subsequently, memory layers 27 may be formed in the channel holes, respectively. Each of the memory layers 27 may include at least one of a charge blocking layer 27A, a data storage layer 27B, and a tunnel insulating layer 27C. Subsequently, channel layers 28 may be formed in the channel holes, respectively. The channel layers 28 may include gap-fill layers 29, respectively. Subsequently, an interlayer insulating layer 30 may be formed on the stack structure ST.
[0042] Referring to
[0043] Referring to
[0044] Referring to
[0045] Referring to
[0046] Referring to
[0047] Referring to
[0048]
[0049] Referring to
[0050] R1 with a conductive material. When the first recess region R1 is formed, the barrier layer 36 may also be etched. The source contact pad 37 may include a polysilicon layer, a metal layer, or the like. For example, the source contact pad 37 may include a polysilicon layer including a dopant. More specifically, the source contact pad 37 may be a polysilicon layer doped with an N-type or P-type dopant. For example, the source contact pad 37 and the source contact structure 35 may include the same type of dopant or different types of dopant.
[0051] In addition, a second recess region R2 may be formed by etching the interlayer insulating layer 30 to expose the channel layers 28 of the channel structures CH. Subsequently, a wire 38 for bit lines that is coupled to the channel layers 28 may be formed by filling the second recess region R2 with a conductive material.
[0052] According to the embodiments described above, an etch prevention layer may be formed in an interface between a sacrificial layer and the stack structure ST, such that the stack structure ST may be prevented from being etched during an etching process for exposing the channel layer 28 of the lower portion of the channel structure CH. Accordingly, the distance d between the conductive layer (32) that serves as a select transistor and the second source layer 34 may be reduced. Thus, a distance by which impurities, doped to a source structure, diffuse may be minimized and a junction overlap region may be easily formed, such that a GIDL current may be stably generated during an erase operation. In addition, off characteristics of the select transistor may be improved, such that the semiconductor device may be designed to minimize the number of select transistors to be disposed and the integration density of the semiconductor device may also be improved.
[0053]
[0054] Referring
[0055] The memory device 1200 may be used to store data information having various data formats such as a text format, a graphical format, and a software code format. The memory device 1200 may be a non-volatile memory device. Furthermore, the memory device 1200 may have the structures described above with reference to
[0056] The controller 1100 may be coupled to a host and the memory device 1200 and configured to access the memory device 1200 in response to a request from the host. For example, the controller 1100 may control read, write, erase, and background operations of the memory device 1200.
[0057] The controller 1100 may include Random Access Memory (RAM) 1110, a Central Processing Unit (CPU) 1120, a host interface 1130, an Error Correction Code (ECC) circuit 1140, a memory interface 1150, and the like.
[0058] The RAM 1110 may serve as operational memory of the CPU 1120, cache memory between the memory device 1200 and the host, buffer memory between the memory device 1200 and the host, or the like. The RAM 1110 may be replaced with Static Random Access Memory (SRAM), Read Only Memory (ROM), or the like.
[0059] The CPU 1120 may control the overall operations of the controller 1100. For example, the CPU 1120 may operate firmware such as a Flash Translation Layer (FTL) stored in the RAM 1110.
[0060] The host interface 1130 may interface with the host. For example, the controller 1100 may communicate with the host through at least one of various interface protocols such as a Universal Serial Bus (USB) protocol, a MultiMedia Card (MMC) protocol, a Peripheral Component Interconnection (PCI) protocol, a PCI-Express (PCI-E) protocol, an Advanced Technology Attachment (ATA) protocol, a Serial-ATA protocol, a Parallel-ATA protocol, a Small Computer System Interface (SCSI) protocol, an Enhanced Small Disk Interface (ESDI) protocol, an Integrated Drive Electronics (IDE) protocol, and a private protocol.
[0061] The ECC circuit 1140 may use an error correction code (ECC) to detect and correct errors in data read from the memory device 1200.
[0062] The memory interface 1150 may interface with the memory device 1200. For example, the memory interface 1150 may include a NAND interface or a NOR interface.
[0063] The controller 1100 may further include buffer memory (not shown) for temporarily storing data. The buffer memory may be used to temporarily store data to be transferred to an external device through the host interface 1130 or data to be transferred from the memory device 1200 through the memory interface 1150. The controller 1100 may further include ROM which stores code data to interface with the host.
[0064]
[0065] Referring to
[0066] The memory device 1200′ may be a non-volatile memory device. Furthermore, the memory device 1200′ may have the structures described above with reference to
[0067] Furthermore, the memory device 1200′ may be a multi-chip package including a plurality of memory chips. The plurality of memory chips may be divided into a plurality of groups, which may communicate with the controller 1100 through first to kth channels CH1 to CHk, respectively. In addition, memory chips included in a single group may be suitable for communicating with the controller 1100 through a common channel. The memory system 1000′ may be modified so that a single memory chip may be coupled to a single channel.
[0068] Because the memory device 1200′ is formed into a multi-chip package, data storage capacity and a driving speed of the memory system 1000′ may be increased.
[0069]
[0070] Referring to
[0071] The memory device 2100 may store data provided via the user interface 2400, data processed by the CPU 2200, and the like. The memory device 2100 may be electrically coupled to the CPU 2200, the RAM 2300, the user interface 2400, and the power supply 2500 through the system bus 2600. For example, the memory device 2100 may be coupled to the system bus 2600 through a controller (not shown), alternatively, directly coupled to the system bus 2600. When the memory device 2100 is directly coupled to the system bus 2600, functions of the controller may be performed by the CPU 2200 and the RAM 2300.
[0072] The memory device 2100 may be a non-volatile memory device. Furthermore, the memory device 2100 may have the structures described above with reference to
[0073] In addition, as described above with reference to
[0074] The computing system 2000 having the above-described configuration may be provided as a computer, an Ultra Mobile PC (UMPC), a workstation, a net-book, Personal Digital Assistants (PDAs), a portable computer, a web tablet, a wireless phone, a mobile phone, a smartphone, an e-book, a Portable
[0075] Multimedia Player (PMP), a portable game console, a navigation device, a black box, a digital camera, a 3-dimensional television, a digital audio recorder, a digital audio player, a digital picture recorder, a digital picture player, a digital video recorder, a digital video player, a device capable of transmitting/receiving information in an wireless environment, one of various electronic devices for forming a home network, one of various electronic devices for forming a computer network, one of various electronic devices for forming a telematics network, an RFID device, or the like.
[0076]
[0077] Referring to
[0078] The operating system 3200 may manage software and hardware resources of the computing system 3000. The operating system 3200 may control program execution of a central processing unit. The application 3100 may be various application programs executed in the computing system 3000. The application 3100 may be a utility executed by the operating system 3200.
[0079] The file system 3300 may refer to a logical structure configured to manage data and files present in the computing system 3000. The file system 3300 may organize files or data to be stored in the memory device 3500 according to given rules. The file system 3300 may be determined according to the operating system 3200 used in the computing system 3000. For example, when the operating system 3200 is a Microsoft Windows-based system, the file system 3300 may be a File Allocation Table (FAT), an NT file system (NTFS), or the like. In addition, when the operating system 3200 is a Unix/Linux-based system, the file system 3300 may be an extended file system (EXT), a Unix File System (UFS), a Journaling File System (JFS), or the like.
[0080]
[0081] The translation layer 3400 may translate an address into a suitable form for the memory device 3500 in response to a request from the file system 3300. For example, the translation layer 3400 may translate a logical address, generated by the file system 3300, into a physical address of the memory device 3500. Mapping information of the logical address and the physical address may be stored in an address translation table. For example, the translation layer 3400 may be a Flash Translation Layer (FTL), a Universal Flash Storage Link Layer (ULL), or the like.
[0082] The memory device 3500 may be a non-volatile memory device. Furthermore, the memory device 3500 may have the structures described above with reference to
[0083] The computing system 3000 having the above-described configurations may be divided into an operating system layer that is operated in an upper level region and a controller layer that is operated in a lower level region. The application 3100, the operating system 3200, and the file system 3300 may be included in the operating system layer, and may be driven by operational memory of the computing system 3000. The translation layer 3400 may be included in the operating system layer or the controller layer.
[0084] As described above, according to the present disclosure, the electrical characteristics of a semiconductor device may be improved by reducing a distance by which an impurity of a source structure coupled to a lower portion of a channel of the semiconductor device diffuses.
[0085] Embodiments have been disclosed herein, and although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for the purpose of limitation. Accordingly, it will be understood by a person of ordinary skill in the art to which the disclosure pertains that various changes in forms and details may be made without departing from the spirit and scope of the descriptions as set forth in the following claims.