Semiconductor Device

Abstract

To provide a semiconductor device having a high vertical height and including a channel structure extending in a vertical direction and capable of improving electric characteristics, and methods for operating and manufacturing the same.SOLUTION: A semiconductor device includes: a channel structure C140 arranged on a substrate 110 and extending in a first direction vertical to an upper surface of the substrate; a plurality of gate electrodes 130 arranged on the substrate and separated in a first direction on a sidewall of the channel structure; and a gate insulation layer 132 arranged between each of the plurality of gate electrodes and the channel structure. The channel structure includes a body gate layer 146 extending in the first direction, a charge conservation structure 144 surrounding a sidewall of the body gate layer, and a channel layer 142 surrounding a sidewall of the charge conservation structure.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a semiconductor device and a method for operating the same, and more particularly to a semiconductor device including a vertically extending channel structure and a method for operating the same, as well as a method for manufacturing the same. [Background technology]

[0002] As the integration density of memory devices increases, memory devices having a vertical transistor structure have been proposed instead of memory devices having existing planar transistor structures. A memory device having a vertical transistor structure includes a channel structure that extends vertically on a substrate. However, as the integration density of memory devices increases, the number of gate electrode layers stacked vertically increases, which increases the difficulty of the manufacturing process. Summary of the Invention [Problem to be solved by the invention]

[0003] An object of the present invention is to provide a semiconductor device that has a large vertical height and yet has improved electrical characteristics.

[0004] Another problem to be solved by the technical concept of the present invention is to provide a method for operating a semiconductor device that can improve electrical characteristics while having a large vertical height. [Means for solving the problem]

[0005] A semiconductor device according to the technical idea of ​​the present invention for solving the above problem includes a channel structure disposed on a substrate and extending in a first direction perpendicular to an upper surface of the substrate, the channel structure including a body gate layer extending in the first direction, a charge storage structure surrounding sidewalls of the body gate layer, and a channel layer surrounding sidewalls of the charge storage structure; a plurality of gate electrodes disposed on the substrate and spaced apart in the first direction on sidewalls of the channel structure; and a gate insulating layer disposed between each of the plurality of gate electrodes and the channel structure.

[0006] A semiconductor device according to the technical idea of ​​the present invention for solving the above problem includes: a plurality of gate electrodes disposed on a substrate and spaced apart in a first direction perpendicular to an upper surface of the substrate; a channel structure disposed in a channel hole extending in the first direction through the plurality of gate electrodes, the channel structure including a channel layer disposed on an inner wall of the channel hole and a charge storage structure disposed on the channel layer on the inner wall of the channel hole; and a gate insulating layer disposed between each of the plurality of gate electrodes and the channel layer and covering upper and bottom surfaces of each of the plurality of gate electrodes; the channel layer is disposed between each of the plurality of gate electrodes and the charge storage structure.

[0007] A semiconductor device according to the technical idea of ​​the present invention for solving the above problem includes: a channel structure disposed on a substrate and extending in a first direction perpendicular to an upper surface of the substrate, the channel structure including a body gate layer extending in the first direction, a charge storage structure surrounding sidewalls of the body gate layer, and a channel layer surrounding sidewalls of the charge storage structure; a plurality of gate electrodes disposed on the substrate and spaced apart in the first direction on sidewalls of the channel structure; a gate insulating layer disposed between each of the plurality of gate electrodes and the channel structure; a bit line pad formed at a higher level than an uppermost gate electrode among the plurality of gate electrodes and disposed on the channel layer; a bit line contact connected to the bit line pad; and a bit line connected to the bit line contact and extending in a second direction parallel to the upper surface of the substrate. [Brief description of the drawings]

[0008] [Figure 1] 1 is an equivalent circuit diagram of a memory cell array of a semiconductor device according to an exemplary embodiment. [Diagram 2] 1 is a plan view showing a representative configuration of a semiconductor device according to an exemplary embodiment; [Diagram 3] FIG. 3 is a schematic perspective view of a portion A1 of FIG. 2. [Figure 4A] FIG. 3 is an enlarged plan view of a portion A2 in FIG. [Figure 4B] FIG. 3 is an enlarged plan view of a portion A2 in FIG. [Diagram 5] 3 is a cross-sectional view taken along line B1-B1' in FIG. 2. [Figure 6] 3 is a cross-sectional view taken along line B2-B2' in FIG. 2. [Figure 7] FIG. 7 is an enlarged view of a portion CX1 in FIG. [Figure 8] 4 is a timing diagram of programming voltages applied to memory cells being programmed in an exemplary programming operation of a semiconductor device according to an exemplary embodiment. [Figure 9]FIG. 11 is a circuit diagram illustrating voltages applied to a program string, an inhibit string, and a body gate line in a programming operation according to an example embodiment. [Figure 10] 10 is a schematic energy band diagram of components included in a memory cell programmed in step 3 of FIG. 9; [Figure 11] 1 is a circuit diagram illustrating voltages applied to a string and body gate line from which a read is performed in an exemplary read operation of a semiconductor device according to an exemplary embodiment. [Figure 12] 1 is a circuit diagram illustrating voltages applied to a string and a body gate line to be erased in an exemplary erase operation of a semiconductor device according to an exemplary embodiment. [Figure 13] 1 is a cross-sectional view illustrating a semiconductor device according to an exemplary embodiment. [Figure 14] FIG. 14 is an enlarged cross-sectional view of a portion CX2 in FIG. 13. [Figure 15] 1 is a cross-sectional view illustrating a semiconductor device according to an exemplary embodiment. [Figure 16] FIG. 16 is an enlarged cross-sectional view of a portion CX3 in FIG. [Figure 17] 1 is a cross-sectional view illustrating a semiconductor device according to an exemplary embodiment. [Figure 18] FIG. 18 is an enlarged cross-sectional view of a portion CX4 in FIG. 17. [Figure 19] 1 is a cross-sectional view illustrating a semiconductor device according to an exemplary embodiment. [Figure 20] 1 is a cross-sectional view illustrating a semiconductor device according to an exemplary embodiment. [Figure 21] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Figure 22] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Figure 23] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Figure 24]1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Diagram 25] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Figure 26] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Figure 27] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Figure 28] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Figure 29] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Diagram 30] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Diagram 31] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Diagram 32] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Diagram 33] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Diagram 34] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Diagram 35] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Diagram 36] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Figure 37] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. [Figure 38] 1A to 1C are schematic diagrams illustrating a method for manufacturing a semiconductor device according to an exemplary embodiment in a process sequence. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the technical concept of the present invention will be described in detail with reference to the accompanying drawings.

[0010] An ingredient that is located "on" another ingredient will be understood to be located above or below the other ingredient. An ingredient that is located on another ingredient will be further understood to be located "directly" on the other ingredient, such that the ingredients can be in direct contact with each other, or located "indirectly" on the other ingredient, such that the ingredients are separated from direct contact with each other by one or more intervening spaces and / or structures.

[0011] Spatial comparison terms such as "below," "lower," "above," and "top" are used herein for convenience of description to describe the relationship of one component or feature to another component or feature as shown in the drawings. It will be understood that the spatial comparison terms are intended to include other orientations of the device in use or operation in addition to the orientation shown in the drawings. For example, if the device were turned upside down in the drawings, a component described as being located "below" another component or feature would be arranged "above" the other component or feature. Thus, the illustrative term "below" includes both an upside-down and upside orientation. Devices can be arranged differently (rotated 90 degrees or in other orientations) and the spatial comparison terms used herein will be interpreted accordingly. Furthermore, when an element is referred to as being "between" two elements, the element may be the only element between the two elements or there may be one or more other intervening elements.

[0012] FIG. 1 is an equivalent circuit diagram of a memory cell array MCA of a semiconductor device according to an exemplary embodiment, and in particular, an equivalent circuit diagram of a vertical NAND (VNAND) flash memory device having a vertical channel structure.

[0013] Referring to FIG. 1, the memory cell array MCA includes memory cell strings MCS11 to MCS33, word lines WL1 to WL8, ground selection lines GSL1 to GSL3, string selection lines SSL1 to SSL3, and a common source line CSL.

[0014] Memory cell strings MCS11, MCS21, and MCS31 are provided between a first bit line BL1, a first body gate line BGL1, and a common source line CSL, memory cell strings MCS12, MCS22, and MCS32 are provided between a second bit line BL2, a second body gate line BGL2, and a common source line CSL, and memory cell strings MCS13, MCS23, and MCS33 are provided between a third bit line BL3, a third body gate line BGL3, and a common source line CSL. For example, each memory cell string MCS11 includes a string selection transistor SST, a plurality of memory cells MCT1 to MCT8, and a ground selection transistor GST, which are connected in series.

[0015] The string selection transistors SST are connected to corresponding string selection lines SSL1 to SSL3. A plurality of memory cells MCT1 to MCT8 are connected to corresponding word lines WL1 to WL8, respectively. The ground selection transistors GST are connected to corresponding ground selection lines GSL1 to GSL3. The string selection transistors SST are connected to corresponding bit lines BL1 to BL3, and the ground selection transistors GST are connected to a common source line CSL.

[0016] In some embodiments, for example, the word lines WL1 of the same height are commonly connected to each other, the string select lines SSL1 to SSL3 are separated from each other, and the ground select lines GSL1 to GSL3 are also separated from each other. Although FIG. 1 shows three string select lines SSL1 to SSL3 sharing a word line of the same height, the present invention is not limited thereto. In some examples, two string select lines may share a word line of the same height. In other examples, four string select lines may share a word line of the same height.

[0017] FIG 2 is a plan view showing a representative configuration of a semiconductor device 100 according to an exemplary embodiment. FIG 3 is a schematic perspective view of the A1 portion of FIG 2, and FIG 4A and FIG 4B are enlarged plan views of the A2 portion of FIG 2. FIG 5 is a cross-sectional view taken along the B1-B1' line of FIG 2, FIG 6 is a cross-sectional view taken along the B2-B2' line of FIG 2, and FIG 7 is an enlarged view of the CX1 portion of FIG 6. In FIG 2 to FIG 4B, for convenience of illustration and understanding, only a part of the configuration of the semiconductor device 100 is shown in a schematic manner.

[0018] 2 to 7, the substrate 110 includes a memory cell region MCR, a connection region CON, and a peripheral circuit region PERI. A memory cell array MCA is disposed on the memory cell region MCR, and the memory cell array MCA is also a vertical channel structure NAND memory device that operates in the manner described with reference to FIG. 1. A peripheral circuit transistor 190T for driving the memory cell array MCA is disposed on the peripheral circuit region PERI. The peripheral circuit transistor 190T includes a peripheral circuit active region 192, a peripheral circuit gate electrode 194 disposed on the peripheral circuit active region 192, and a peripheral circuit contact 196 connected to the peripheral circuit active region 192 and the peripheral circuit gate electrode 194. The connection region CON is also a region in which a pad part PAD for connecting the memory cell array MCA disposed in the memory cell region MCR to the peripheral circuit transistor 190T is formed.

[0019] The substrate 110 has a main surface 110M extending in a first direction (X-direction) and a second direction (Y-direction). The substrate 110 includes a semiconductor material, such as a group IV semiconductor, a group III-V compound semiconductor, or a group II-VI oxide semiconductor. For example, the group IV semiconductor includes silicon (Si), germanium (Ge), or silicon-germanium. The substrate 110 may also be provided as a bulk wafer or an epitaxial layer. In other embodiments, the substrate 110 may include a silicon-on-insulator (SOI) substrate or a germanium-on-insulator (GeOI) substrate.

[0020] On the memory cell region MCR of the substrate 110, a plurality of first insulating layers 120 and a plurality of gate electrodes 130 are alternately arranged along a third direction (Z direction) perpendicular to the main surface 110M of the substrate 110. For example, the first insulating layers 120 and the gate electrodes 130 are alternately and repeatedly arranged on the substrate 110. A second insulating layer 122 is arranged on the uppermost gate electrode 130.

[0021] The plurality of gate electrodes 130 includes a metal layer 130M and a conductive barrier layer 130UB surrounding the top, bottom and side surfaces of the metal layer 130M. The conductive barrier layer 130UB includes titanium nitride (TiN), tantalum nitride (TaN), tungsten nitride (WN), ruthenium (Ru), titanium (Ti), tantalum (Ta), or a combination thereof. The metal layer 130M includes at least one of cobalt (Co), tungsten (W), nickel (Ni), ruthenium (Ru), copper (Cu), aluminum (Al), a silicide thereof, or an alloy thereof. In an exemplary embodiment, each of the plurality of gate electrodes 130 has a thickness along the third direction (Z direction) of about 1 to about 30 nm, or about 1 to about 15 nm, or about 15 to about 30 nm, or about 15 nm. However, the thickness of each of the plurality of gate electrodes 130 is not limited thereto.

[0022] When the term "about" or "approximately" is used herein in conjunction with a numerical value, the associated numerical value is intended to include a tolerance of ±10% around the stated numerical value. When a range is specified, the range includes all values ​​therebetween, such as in increments of 0.1%.

[0023] In an exemplary embodiment, the gate electrodes 130 correspond to the ground selection lines GSL1 to GSL3, the word lines WL1 to WL8, and the string selection lines SSL1 to SSL3 that constitute the memory cell strings MCS11 to MCS33 (FIG. 1). For example, the bottom gate electrode 130 functions as the ground selection lines GSL1 to GSL3, the top gate electrode 130 functions as the string selection lines SSL1 to SSL3, and the remaining gate electrodes 130 function as the word lines WL1 to WL8. In some embodiments, the gate electrode 130 disposed immediately below the top gate electrode 130 or the gate electrode 130 disposed immediately above the bottom gate electrode 130 may function as a dummy word line. Thereby, the memory cell strings MCS11 to MCS33 are provided in which the ground selection transistors GST, the selection transistors SST, and the memory cells MCT1 to MCT8 therebetween are connected in series.

[0024] The channel structures C140 extend in a vertical direction (Z direction) from the main surface 110M of the substrate 110 through the gate electrodes 130 in the memory cell region MCR. The channel structures C140 are arranged at predetermined intervals along a first direction (X direction), a second direction (Y direction), and a fourth direction (e.g., a diagonal direction). The channel structures C140 are arranged in a zigzag or staggered pattern.

[0025] Each of the channel structures C140 is disposed in a channel hole C140H penetrating the gate electrodes 130, the first insulating layers 120, and the second insulating layer 122. A channel layer 142, a charge storage structure 144, and a body gate layer 146 are sequentially disposed on an inner wall of the channel hole C140H.

[0026] The channel layer 142 is conformally formed on the inner wall of the channel hole C140H, and the channel layer 142 includes a bottom 142L that contacts the substrate 110. The bottom 142L of the channel layer 142 (or the bottom surface C142L of the channel structure C140) is disposed at a level lower than the main surface 110M of the substrate 110. For example, the bottom of the channel hole C140H is recessed from the main surface 110M of the substrate 110, and the bottom 142L of the channel layer 142 is disposed at the bottom of the channel hole C140H and contacts the upper surface of the substrate 110 that is disposed at the bottom of the channel hole C140H.

[0027] The charge storage structure 144 includes a tunneling dielectric layer 144A, a charge storage layer 144B, and a blocking dielectric layer 144C, which are sequentially formed on the sidewall 142IS of the channel layer 142. That is, the channel layer 142, the tunneling dielectric layer 144A, the charge storage layer 144B, and the blocking dielectric layer 144C are sequentially disposed on the inner wall of the channel hole C140H. The relative thicknesses of the tunneling dielectric layer 144A, the charge storage layer 144B, and the blocking dielectric layer 144C constituting the charge storage structure 144 are not limited to those illustrated in FIG. 7 and may be variously modified.

[0028] In an exemplary embodiment, the tunneling dielectric film 144A includes silicon oxide, hafnium oxide, aluminum oxide, zirconium oxide, tantalum oxide, etc. The charge storage film 144B is a region in which electrons passing through the tunneling dielectric film 144A from the channel layer 142 are stored, and includes silicon nitride, boron nitride, silicon boron nitride, or polysilicon doped with impurities. The blocking dielectric film 144C includes silicon oxide, silicon nitride, or a metal oxide having a higher dielectric constant than silicon oxide. The metal oxide includes hafnium oxide, aluminum oxide, zirconium oxide, tantalum oxide, or a combination thereof.

[0029] The body gate layer 146 fills the remaining space of the channel hole C140H above the charge storage structure 144. In an exemplary embodiment, the body gate layer 146 includes, but is not limited to, a doped polysilicon layer. When a data write operation, a read operation, or an erase operation is performed on the memory cells MCT1 through MCT8 (FIG. 1), a predetermined voltage (or signal) is applied to the body gate layer 146 from the body gate lines BGL1 through BGL3 (FIG. 1).

[0030] In an exemplary embodiment, the body gate layer 146 has a columnar shape extending vertically (Z direction) in the channel hole C140H. The top surface of the body gate layer 146 is disposed at the same level as the top surface of the second insulating layer 122, and the bottom surface of the body gate layer 146 is disposed at a lower level than the bottom surface of the bottom gate electrode 130. The sidewall 146S and bottom surface of the body gate layer 146 contact the charge storage structure 144. For example, as shown in FIG. 7, the sidewall 146S of the body gate layer 146 is surrounded by the charge storage structure 144, and the outer wall 144S of the charge storage structure 144 is surrounded by the channel layer 142. The outer wall of the channel layer 142 is surrounded by the gate electrode 130, and the inner wall 142IS of the channel layer 142 contacts the outer wall 144S of the charge storage structure 144.

[0031] A gate insulating layer 132 is disposed between the gate electrode 130 and the channel structure C140. The gate insulating layer 132 is interposed between the gate electrode 130 and the channel layer 142 and between the gate electrode 130 and the first insulating layer 120, and covers an upper surface 130U of the gate electrode 130 and a bottom surface 130L of the gate electrode 130. In an exemplary embodiment, the gate insulating layer 132 includes, but is not limited to, silicon oxide.

[0032] A bit line pad 150 is disposed on the channel structure C140 and electrically connected to the channel layer 142. For example, as shown in FIG. 4A, the bit line pad 150 has an annular shape, and an opening 150OP is defined by an inner wall of the bit line pad 150. The bit line pad 150 does not vertically overlap the body gate layer 146, so that the bit line pad 150 is not electrically connected to the body gate layer 146. For example, in a plan view, the outer wall of the bit line pad 150 has an oval shape, and the inner wall of the bit line pad 150 has a circular shape. In a plan view, the inner wall of the bit line pad 150 (e.g., the boundary of the opening 150OP) is disposed to surround the sidewall of the body gate layer 146 by a predetermined interval, so that the bit line pad 150 and the body gate layer 146 are spaced apart from each other. In some embodiments, the outer sidewall of the bit line pad 150 has one of a rounded square, a polygon, a circle, and an oval, and the inner sidewall of the bit line pad 150 has one of a rounded square, a polygon, a circle, and an oval.

[0033] A third insulating layer 124 is disposed on the second insulating layer 122, the third insulating layer 124 surrounding the sidewalls of the bit line pad 150 and disposed at the same vertical level as the bit line pad 150. A fourth insulating layer 126 is disposed on the third insulating layer 124.

[0034] A plurality of bit lines 164 extend in the second direction (Y direction) on the fourth insulating layer 126. Bit line contacts 162 are disposed in bit line contact holes 162H penetrating the fourth insulating layer 126, and the bit line contacts 162 electrically connect the bit line pads 150 and the bit lines 164. A plurality of body gate lines 168 extend in the second direction (Y direction) on the fourth insulating layer 126. Body gate contacts 166 are disposed in body gate contact holes 166H penetrating the fourth insulating layer 126 and the third insulating layer 124, and the body gate contacts 166 electrically connect the body gate lines 168 and the body gate layer 146. A fifth insulating layer 128 is disposed on the fourth insulating layer 126, surrounding sidewalls of the plurality of bit lines 164 and the plurality of body gate lines 168.

[0035] In an exemplary embodiment, as shown in FIG. 4A, the bit line contact 162 is offset or spaced apart from the center of the channel structure C140, for example, in a first direction (X direction). The bit line pad 150 has a first width w11 along the first direction (X direction) and a second width w12 narrower than the first width w11 along the second direction (Y direction). Thereby, the bit line contact 162 is disposed on the bit line pad 150 (for example, at a position spaced farther away from the center of the channel structure C140), the body gate contact 166 is disposed on the body gate layer 146 (for example, at a position spaced closer to the center of the channel structure C140 than the bit line contact 162), and the plurality of body gate lines 168 are disposed at the same level as the plurality of bit lines 164. The two bit lines 164 disposed side by side are alternately and repeatedly disposed with the two body gate lines 168 disposed side by side.

[0036] In an exemplary embodiment, when two channel structures C140 are disposed in the second direction (Y direction) between the string isolation insulating layer 184 (FIG. 2) and the word line cut region WLC (FIG. 2) as shown in FIG. 4A, a first bit line 164_1 and a first body gate line 168_1 connected to a first channel structure C140_1, which is one of the two channel structures C140, and a second bit line 164_2 and a second body gate line 168_2 connected to a second channel structure C140_2, which is the other of the two channel structures C140, extend parallel to each other along the second direction (Y direction). Thus, the first bit line 164_1, the first body gate line 168_1, the second body gate line 168_2, and the second bit line 164_2 are sequentially disposed in the first direction (X direction).

[0037] In some embodiments, as shown in FIG. 4B, a first bit line 164_1 and a first body gate line 168_1 connected to a first channel structure C140_1, which is one of two channel structures C140 arranged side by side in the second direction (Y direction), and a second bit line 164_2 and a second body gate line 168_2 connected to a second channel structure C140_2, which is the other of the two channel structures C140, extend parallel to each other along the second direction (Y direction), where the first bit line 164_1, the second body gate line 168_2, the first body gate line 168_1, and the second bit line 164_2 are sequentially arranged in the first direction (X direction). In such a case, since the separation distance between the first bit line contact 162 connected to the first bit line 164_1 and the first body gate contact 166 connected to the first body gate line 168_1 is relatively large, the process margin in the process of forming the bit line contact hole 162H and the body gate contact hole 166H can be increased.

[0038] In some embodiments, unlike those shown in Figures 4A and 4B, the body gate lines 168 may extend along the second direction (Y direction) at a different vertical level than the bit lines 164.

[0039] 2, on the substrate 110, a plurality of word line cut regions WLC extend along a first direction (X direction) parallel to the main surface 110M of the substrate 110. A plurality of gate electrodes 130 arranged between a pair of word line cut regions WLC constitute one block, and the pair of word line cut regions WLC limit the width of the plurality of gate electrodes 130 along the second direction (Y direction).

[0040] A plurality of common source lines 180 vertically overlapping with the plurality of word line cut regions WLC are arranged along a first direction (X direction) on the substrate 110. Insulating spacers 182 are arranged on both side walls of the plurality of common source lines 180. In FIG. 6, the plurality of common source lines 180 are shown as having bottom surfaces arranged at a level lower than the major surface 110M of the substrate 110, but in some embodiments, the plurality of common source lines 180 may have bottom surfaces arranged at the same level as the major surface 110M of the substrate 110.

[0041] A plurality of common source regions 112 are arranged in the first direction (X direction) inside the substrate 110 under the common source line 180. The plurality of common source regions 112 are impurity regions doped with a high concentration of n-type impurities. The plurality of common source regions 112 function as source regions that supply current to the memory cells. The plurality of common source regions 112 are arranged at positions overlapping with a plurality of word line cut regions WLC.

[0042] 2, within one block, the uppermost gate electrode 130 is divided into two parts in a plane by the string isolation insulating layer 184. Although not shown, the string isolation insulating layer 184 extends from the same level as the upper surface of the second insulating layer 122 to a level lower than the bottom surface of the uppermost gate electrode 130.

[0043] In the connection region CON, the multiple gate electrodes 130 extend to form a pad portion PAD. The multiple gate electrodes 130 extend so as to have a length that gradually shortens along the first direction (X direction) as they become farther from the main surface 110M of the substrate 110 (FIG. 5). The pad portion PAD refers to a portion of the multiple gate electrodes 130 arranged in a stepped manner. A second insulating layer 122 is arranged on the multiple gate electrodes 130 that form the pad portion PAD, and pad contacts 172 that penetrate the second insulating layer 122 and are connected to the multiple gate electrodes 130 are arranged in the connection region CON.

[0044] 5, the multiple dummy channel structures D140 are disposed in the connection region CON inside a dummy channel hole D140H penetrating the multiple gate electrodes 130, and extend in a third direction (Z direction) from the main surface 110M of the substrate 110. The dummy channel structure D140 is formed in the manufacturing process of the semiconductor device 100 to ensure the structural stability of the semiconductor device 100. Each of the multiple dummy channel structures D140 has the same structure as the channel structure C140. Each of the multiple dummy channel structures D140 has the same width as the channel structure C140 or a width larger than that of the channel structure C140.

[0045] In general, a semiconductor device uses a method of storing data by injecting charges into a charge storage structure disposed between a gate electrode and a channel layer using a Fowler-Nordheim (FN) tunneling method, and therefore the charge storage structure and the channel layer are sequentially formed in a channel hole. However, as the vertical height of the semiconductor device increases, the difficulty of forming a cell contact layer by selective epitaxial growth (SEG) at the bottom of the channel hole or etching the charge storage structure at the bottom of the channel hole in order to electrically connect the channel layer to a substrate increases significantly, so there is a restriction on increasing the vertical height of the semiconductor device.

[0046] However, according to the above-described exemplary embodiment, the channel layer 142, the charge storage structure 144, and the body gate layer 146 are sequentially formed in the channel hole C140H, and charges are injected into the charge storage structure 144 by voltages applied independently to the gate electrode 130 and the body gate layer 146, respectively, to store data. That is, a highly difficult manufacturing process such as a process of forming a cell contact by a SEG at the bottom of the channel hole C140H or a process of etching the charge storage structure 144 at the bottom of the channel hole C140H is not required. Therefore, the semiconductor device 100 can realize an increase in vertical height or a high integration density. In addition, as described below, by applying a programming voltage through the body gate layer 146, disturbance between word lines is significantly reduced, and therefore the semiconductor device 100 can have improved cell operating characteristics or improved electrical characteristics.

[0047] An exemplary method of driving the semiconductor device 100 will now be described with reference to FIGS.

[0048] FIG. 8 shows a timing diagram of programming voltages applied to a memory cell to be programmed in an exemplary programming operation of the semiconductor device 100. FIG. 9 shows a circuit diagram showing voltages applied to a program string, an inhibit string, and a body gate line in a programming operation. FIG. 10 shows a schematic energy band diagram of components included in a memory cell to be programmed in step 3 of FIG. 9. FIG. 11 shows a circuit diagram showing voltages applied to a string to be read and a body gate line in an exemplary read operation of the semiconductor device 100. FIG. 12 shows a circuit diagram showing voltages applied to a string to be erased and a body gate line in an exemplary erase operation of the semiconductor device 100.

[0049] 8 to 12 exemplarily illustrate programming, reading and erasing operations of one memory cell MCT1 (FIG. 1) provided between one bit line BL1 (FIG. 1), one body gate line BGL1 (FIG. 1), and one word line WL1 (FIG. 1).

[0050] 8 and 9, an exemplary programming operation of the semiconductor device 100 is performed according to a sequence including steps 1 to 3 in sequence.

[0051] In step 1, a voltage of 0V is applied to a string STRpg (hereinafter referred to as a "programming string") including a memory cell MCPG to be programmed through a bit line connected thereto. A power supply voltage Vcc is applied to a string STRin (hereinafter referred to as an "inhibit string") connected to the remaining bit lines except for the bit line connected to the programming string STRpg through a bit line. A pass voltage Vpass is applied to all word lines WL(Unsel), WL(Sel) (i.e., both the unselected word line WL(Unsel) and the selected word line WL(Sel)). A voltage of 0V is applied to a body gate line BGpg (hereinafter referred to as a "programming body gate line") disposed adjacent to the memory cell MCPG to be programmed. During step 1, electrons are charged in the channel of the programming string STRpg.

[0052] In step 2, a voltage of 0 V is applied to the unselected word line WL(Unsel) while a pass voltage Vpass is applied to the selected word line WL(Sel), and a voltage of 0 V is applied to the programming body gate line BGpg. During step 2, electrons are accumulated in the channel of the selected word line WL(Sel).

[0053] In step 3, a programming voltage Vpgm is applied to the programming body gate line BGpg, and a voltage of 0V is applied to the selected word line WL(Sel). Meanwhile, the bit lines connected to the programming string STRpg and the unselected word lines WL(Unsel) are floated. In an exemplary embodiment, the programming voltage Vpgm may have a value higher than the pass voltage Vpass. In step 3, as exemplarily shown in FIG. 10, electrons tunnel from the channel layer 142 of the memory cell MCPG formed by the selected word line WL(Sel) (e.g., the selected gate electrode 130) toward the body gate layer 146, and are injected into the charge storage structure 144 (e.g., the charge storage film 144B) disposed between the channel layer 142 and the body gate layer 146. In some embodiments, the programming voltage Vpgm has a value lower than the programming voltage applied to the selected word line in a typical semiconductor device, but is not limited thereto.

[0054] 11, an exemplary read operation of the semiconductor device 100 is performed in units of a page. For example, a sweep voltage Vsweep is applied to a selected word line WL(Sel) of the string STRread in which a read operation is performed, a read voltage Vread is applied to an unselected word line WL(Unsel), and a voltage of 0V is applied to a body gate line BGread in which a read operation is performed, thereby performing a read operation. At that time, a string selection voltage Vssl and a ground selection voltage Vgsl are applied to a string selection line SSL and a ground selection line GSL of the string STRread in which a read operation is performed, respectively.

[0055] 12, an exemplary erase operation of the semiconductor device 100 is performed in units of blocks. For example, an erase voltage Vers is applied to the well region PPW of the string STRers on which the erase operation is performed, a voltage of 0V is applied to the body gate line BGers on which the erase operation is performed, and all word lines WL are floated to perform the erase operation of the memory cell block.

[0056] According to the above-described exemplary embodiment, the semiconductor device 100 performs a programming operation of the memory cell MCPG by applying a programming voltage Vpgm to the programming body gate line BGpg according to a sequence including steps 1 to 3 in sequence, particularly during step 3. In a conventional semiconductor device, a programming operation is performed by applying a programming voltage to a selected word line and a pass voltage to an unselected word line. In such a case, a relatively large voltage difference is applied between adjacent word lines having a relatively short separation distance, and a cell operation failure occurs due to disturbance between the adjacent word lines. However, according to the exemplary embodiment, a relatively low voltage (e.g., a pass voltage) is applied to the word line compared to the programming voltage applied to the body gate line, so that the disturbance between the word lines is significantly reduced, and the semiconductor device 100 can have improved cell operation characteristics or improved electrical characteristics.

[0057] Fig. 13 is a cross-sectional view showing a semiconductor device 100A according to an exemplary embodiment, and Fig. 14 is an enlarged cross-sectional view of a portion CX2 in Fig. 13. In Figs. 13 and 14, reference numerals similar to those in Figs. 1 to 12 denote similar components.

[0058] 13 and 14, the channel structure C140A further includes a conductive barrier layer 148 disposed between the charge storage structure 144 and the body gate layer 146. Thus, a sidewall 146S of the body gate layer 146 is surrounded by the conductive barrier layer 148.

[0059] In an exemplary embodiment, the body gate layer 146 includes at least one of cobalt (Co), tungsten (W), nickel (Ni), ruthenium (Ru), copper (Cu), aluminum (Al), a suicide thereof, or an alloy thereof. The conductive barrier layer 148 includes titanium nitride (TiN), tantalum nitride (TaN), tungsten nitride (WN), ruthenium (Ru), titanium (Ti), tantalum (Ta), or a combination thereof. Optionally, a high dielectric constant (high-k) insulating film (not shown) may be further formed between the conductive barrier layer 148 and the charge storage structure 144.

[0060] Fig. 15 is a cross-sectional view showing a semiconductor device 100B according to an exemplary embodiment, and Fig. 16 is an enlarged cross-sectional view of a portion CX3 in Fig. 15. In Figs. 15 and 16, reference numerals similar to those in Figs. 1 to 14 denote similar components.

[0061] 15 and 16, a gate insulating layer 132B is disposed between a sidewall 140S of the channel structure C140B and the gate electrode 130B, and the gate insulating layer 132B is not interposed between the gate electrode 130B and the first insulating layer 120. An upper surface 130U and a bottom surface 130L of the gate electrode 130 contact the first insulating layer 120, and the first insulating layer 120 contacts a sidewall C140S of the channel structure C140B (e.g., an outer wall of the channel layer 142).

[0062] In an exemplary embodiment, the gate insulating layer 132B may include a thermal oxide film formed by a thermal oxidation process. For example, the gate insulating layer 132B is formed by removing the sacrificial layer 310 (FIG. 31) to form the gate space 130GS, and then performing a thermal oxidation process on the sidewall of the channel layer 142 exposed to the gate space 130GS, but is not limited thereto.

[0063] Fig. 17 is a cross-sectional view showing a semiconductor device 100C according to an exemplary embodiment, and Fig. 18 is an enlarged cross-sectional view of a portion CX4 in Fig. 17. In Figs. 17 and 18, reference numerals similar to those in Figs. 1 to 16 denote similar components.

[0064] 17 and 18, the bottom of the channel structure C140C is surrounded by a first semiconductor layer 174 and a second semiconductor layer 176. The first semiconductor layer 174 includes polysilicon doped with impurities or undoped polysilicon, and the second semiconductor layer 176 includes polysilicon doped with impurities or undoped polysilicon. The first semiconductor layer 174 serves as a common source line extension region and is a portion corresponding to the common source line CSL of FIG. 1. The second semiconductor layer 176 serves as a support layer for preventing the mold stack from collapsing or falling in a sacrificial layer removal process for forming the first semiconductor layer 174.

[0065] The channel structure C140C extends through the first semiconductor layer 174 and the second semiconductor layer 176 to a level lower than the main surface 110M of the substrate 110. The gate insulating layer 132C is disposed on the inner wall of the channel hole C140H, and is disposed so as to surround the entire side wall C140S and the entire bottom surface of the channel structure C140C, except for the portion of the side wall C140S of the channel structure C140C surrounded by the first semiconductor layer 174. Thereby, the gate insulating layer 132C is disposed between the channel layer 142 and the gate electrode 130B, and between the channel layer 142 and the first insulating layer 120, and the upper surface 130U and the bottom surface 130L of the gate electrode 130B are in contact with the first insulating layer 120.

[0066] 19 is a cross-sectional view showing a semiconductor device 100D according to an exemplary embodiment. In FIG. 19, the same reference numerals as in FIGS. 1 to 18 denote the same components.

[0067] 19, the body gate layer 146 has an upper surface disposed at a lower level than an upper surface of the second insulating layer 122, a sixth insulating layer 129 filling an upper entrance of the channel hole C140H is disposed on the body gate layer 146, and a body gate contact 166 is connected to the body gate layer 146 through the third insulating layer 124, the fourth insulating layer 126, and the sixth insulating layer 129. For example, since the upper surface of the body gate layer 146 is disposed at a lower level than the upper surface of the second insulating layer 122, even if misalignment occurs in the patterning process of the bit line pad 150, undesired electrical connection or short between the bit line pad 150 and the body gate layer 146 can be prevented or reduced.

[0068] 20 is a cross-sectional view showing a semiconductor device 200 according to an exemplary embodiment. In FIG. 20, the same reference numerals as in FIG. 1 to FIG.

[0069] 20, a lower substrate 210 is disposed at a vertical level lower than that of the substrate 110. An active region (not shown) is defined in the lower substrate 210 by an isolation film 222, and a plurality of driving transistors 230T are formed on the active region. The plurality of driving transistors 230T includes a driving circuit gate structure 232 and impurity regions 212 disposed in portions of the lower substrate 210 on both sides of the driving circuit gate structure 232.

[0070] Arranged on the lower substrate 210 are a plurality of wiring layers 242, a plurality of contact plugs 246 connecting between each of the plurality of wiring layers 242 or between the plurality of wiring layers 242 and the driving transistor 230T, and a lower interlayer insulating film 250 covering the plurality of wiring layers 242 and the plurality of contact plugs 246.

[0071] The substrate 110 is disposed on the lower interlayer insulating film 250. On the substrate 110, a plurality of first insulating layers 120, a plurality of gate electrodes 130, a channel structure C140, a bit line 164 (FIG. 5), and a body gate line 168 are disposed.

[0072] 21 to 30 are schematic diagrams showing a manufacturing method of the semiconductor device 100 according to an exemplary embodiment in a process sequence. Specifically, FIGs. 21 to 30 are cross-sectional views corresponding to the cross-section taken along line B2-B2' in FIG. 2. In FIGs. 21 to 30, the same reference numerals as in FIGs. 1 to 20 denote the same components.

[0073] 21, a plurality of first insulating layers 120 and a plurality of sacrificial layers 310 are alternately formed on a major surface 110M of a substrate 110. In an exemplary embodiment, the plurality of first insulating layers 120 may include an insulating material such as silicon oxide, silicon oxynitride, or the like, and the plurality of sacrificial layers 310 may include silicon nitride, silicon oxynitride, or polysilicon doped with impurities, or the like.

[0074] Thereafter, although not shown, the pad part PAD (FIG. 2) is formed by sequentially patterning the first insulating layers 120 and the sacrificial layers 310 in the connection region CON (FIG. 2). In an exemplary embodiment, the pad part PAD is formed in a stepped shape having a difference in upper surface level along the first direction (X direction).

[0075] Thereafter, a second insulating layer 122 is formed to cover the uppermost sacrificial layer 310 and the pad portion PAD. The second insulating layer 122 includes an insulating material such as silicon oxide or silicon oxynitride.

[0076] 22, a mask pattern (not shown) is formed on the second insulating layer 122, and a portion of the second insulating layer 122, the plurality of first insulating layers 120, and the plurality of sacrificial layers 310 is etched using the mask pattern as an etching mask to form a channel hole C140H. The channel hole C140H extends to a level lower than the main surface 110M of the substrate 110.

[0077] 23, a channel layer 142, a tunneling dielectric layer 144A, a charge storage layer 144B, a blocking dielectric layer 144C, and a body gate layer 146 are sequentially formed on the inner wall of the channel hole C140H. Then, a planarization process is further performed to remove the channel layer 142, the tunneling dielectric layer 144A, the charge storage layer 144B, the blocking dielectric layer 144C, and the body gate layer 146 formed on the second insulating layer 122. Here, the tunneling dielectric layer 144A, the charge storage layer 144B, and the blocking dielectric layer 144C are referred to as a charge storage structure 144. As a result of the planarization process, the body gate layer 146 has an upper surface that is substantially coplanar with the upper surfaces of the charge storage structure 144, the channel layer 142, and the second insulating layer 122.

[0078] In the exemplary embodiment, the bottom surface of the channel layer 142 contacts the upper surface of the substrate 110 exposed at the bottom of the channel hole C140H. Therefore, a highly difficult manufacturing process such as a conventionally required SEG process is not required, and the difficulty of the manufacturing process for forming the channel structure C140 is relatively low.

[0079] 24, a mask pattern (not shown) is formed on the second insulating layer 122 and the channel structure C140, and the sacrificial layer 310 and the first insulating layer 120 are removed using the mask pattern as an etching mask to form a word line cut opening 180H. The top surface of the substrate 110 is exposed at the bottom of the word line cut opening 180H.

[0080] 25, the sacrificial layers 310 (FIG. 24) exposed by the word line cut openings 180H are removed to form gate spaces 130GS at the positions where the sacrificial layers 310 have been removed. Sidewalls of the channel layer 142 are exposed in the gate spaces 130GS. In an exemplary embodiment, the process of removing the sacrificial layers 310 may be a wet etching process using a phosphoric acid solution as an etchant.

[0081] 26, a gate insulating layer 132 and a preliminary gate electrode layer 130P are formed on the inner walls of the word line cut opening 180H and the gate spaces 130GS. To form the preliminary gate electrode layer 130P, a conductive barrier layer 130UB (FIG. 7) and a metal layer 130M (FIG. 7) are sequentially formed.

[0082] Referring to FIG. 27, portions of the gate insulating layer 132 and the preliminary gate electrode layer 130P disposed on the second insulating layer 122 and on the inner walls of the word line cut opening 180H are removed, thereby forming the gate insulating layer 132 and the gate electrodes 130 within the multiple gate spaces 130GS.

[0083] Thereafter, impurities are implanted into the inside of the substrate 110 again exposed at the bottom of the word line cut opening 180H to form a common source region 112 in the portion of the substrate 110 disposed at the bottom of the word line cut opening 180H. Thereafter, an insulating spacer 182 is formed on the sidewall of the word line cut opening 180H, and a common source line 180 is formed on the insulating spacer 182 to fill the inside of the word line cut opening 180H.

[0084] 28, a conductive layer (not shown) is formed on the channel structure C140 and the second insulating layer 122, and the conductive layer is patterned to form a bit line pad 150. As shown in FIG. 4A, the bit line pad 150 is formed to have a ring shape, and an inner wall of the bit line pad 150 is spaced a predetermined distance from the body gate layer 146 and is disposed to surround the body gate layer 146. Since the bit line pad 150 is formed by patterning a conductive layer, the thickness of the second insulating layer 122 is relatively thin compared to a semiconductor device according to a comparative example in which a bit line pad is formed in a channel hole C140H.

[0085] 29, a third insulating layer 124 is formed on the bit line pad 150 and the second insulating layer 122, and the top surface of the third insulating layer 124 is planarized until the top surface of the bit line pad 150 is exposed. Then, a fourth insulating layer 126 is formed to cover the top surfaces of the third insulating layer 124 and the bit line pad 150. In some embodiments, the planarization process of the third insulating layer 124 may be omitted, and the third insulating layer 124 may have a top surface that is disposed at a higher level than the top surface of the bit line pad 150, in which case the fourth insulating layer 126 may not be formed.

[0086] Thereafter, a bit line contact hole 162H (FIG. 5) and a body gate contact hole 166H are formed penetrating the third insulating layer 124 and the fourth insulating layer 126. The insides of the bit line contact hole 162H and the body gate contact hole 166H are filled with a conductive material, and a bit line contact 162 and a body gate contact 166 are formed in the bit line contact hole 162H and the body gate contact hole 166H, respectively.

[0087] 30, a bit line 164 and a body gate line 168 connected to a bit line contact 162 and a body gate contact 166, respectively, are formed on the fourth insulating layer 126.

[0088] By carrying out the above-mentioned steps, the semiconductor device 100 is completed.

[0089] In the semiconductor device according to the comparative example, the charge storage structure 144 (i.e., the blocking dielectric layer 144C, the charge storage layer 144B, and the tunneling dielectric layer 144A) is first formed inside the channel hole C140H, and an anisotropic etching process or an etch-back process is performed to remove a portion of the charge storage structure 144 disposed at the bottom of the channel hole C140H and expose the top surface of the substrate 110. Then, a channel layer 142 is formed on the inner wall of the channel hole C140H. However, since the aspect ratio of the channel hole C140H increases as the vertical height of the semiconductor device 100 increases, the difficulty of the anisotropic etching process or the etch-back process for the bottom of the channel hole C140H becomes significantly high. In addition, if the top surface of the substrate 110 is not sufficiently exposed at the bottom of some of the channel holes C140H (if the bottom of the charge storage structure 144 is partially removed), the electrical characteristics of the channel structure C140 formed in such channel hole C140H are not excellent.

[0090] In addition, in the semiconductor device according to the comparative example, in order to obtain low contact resistance between the channel structure C140 and the substrate 110, a cell contact is formed by growing a semiconductor layer from the upper surface of the substrate 110 exposed at the bottom of the channel hole C140H using a selective epitaxial growth (SEG) process. However, it is very difficult to grow a semiconductor layer of uniform height using the SEG process, and as a result, the multiple channel structures C140 are likely to have non-uniform electrical characteristics.

[0091] However, according to the method for manufacturing the semiconductor device 100 according to the exemplary embodiment, the channel layer 142 is formed directly on the inner wall of the channel hole C140H, so that the manufacturing process having a high degree of difficulty as described above can be omitted. Also, the difficulty of the process for forming the bit line pad 150 can be reduced. Therefore, the semiconductor device 100 is advantageous in increasing the vertical height and improving the integration degree.

[0092] 31 and 32 are schematic diagrams showing a manufacturing method of the semiconductor device 100B according to the exemplary embodiment in the order of steps.

[0093] First, the steps described with reference to FIGS. 21 to 25 are performed to form the word line cut opening 180H and a plurality of gate spaces 130GS.

[0094] Referring to FIG. 31, a gate insulating layer 132B is formed on the surface of the channel layer 142 exposed to the plurality of gate spaces 130GS.

[0095] In an exemplary embodiment, the process for forming the gate insulating layer 132B is a thermal oxidation process, and the surface portion of the channel layer 142 is converted into silicon oxide by the thermal oxidation process to form the gate insulating layer 132B. Meanwhile, the gate insulating layer 132B may not be formed on the top and bottom surfaces of the first insulating layer 120 exposed to the gate space 130GS. For example, the gate insulating layer 132B may include a thermal oxide film formed by a thermal oxidation process and may include silicon oxide.

[0096] Referring to FIG. 32, a preliminary gate electrode layer 130P is formed on the word line cut opening 180H and the inner walls of the plurality of gate spaces 130GS.

[0097] Thereafter, the steps described with reference to FIGS. 27 to 30 are carried out to complete the semiconductor device 100B.

[0098] 33 to 38 are schematic diagrams showing a manufacturing method of the semiconductor device 100C according to an exemplary embodiment in a process sequence. Fig. 33 to Fig. 35 are cross-sectional views corresponding to the cross-section taken along line B2-B2' in Fig. 2, and Fig. 36 to Fig. 38 are enlarged cross-sectional views corresponding to the portion CX5 in Fig. 35.

[0099] 33, a first insulating layer 120 is formed on a main surface 110M of a substrate 110, a lower sacrificial layer 320 and a second semiconductor layer 176 are sequentially formed on the first insulating layer 120, and a plurality of first insulating layers 120 and a plurality of sacrificial layers 310 are alternately formed on the second semiconductor layer 176. The lower sacrificial layer 320 is formed using silicon nitride or silicon oxynitride, and the second semiconductor layer 176 is formed using polysilicon doped with impurities or undoped polysilicon.

[0100] Thereafter, the plurality of sacrificial layers 310, the plurality of first insulating layers 120, the second semiconductor layer 176 and a portion of the lower sacrificial layer 320 are etched to form a channel hole C140H. The gate insulating layer 132C, the channel layer 142, the tunneling dielectric layer 144A, the charge storage layer 144B, the blocking dielectric layer 144C and the body gate layer 146 are sequentially formed in the channel hole C140H, and a planarization process is performed to remove the portions of the channel layer 142, the tunneling dielectric layer 144A, the charge storage layer 144B, the blocking dielectric layer 144C and the body gate layer 146 formed on the second insulating layer 122. Thus, a channel structure C140C is formed.

[0101] 34, the plurality of sacrificial layers 310, the plurality of first insulating layers 120, the second semiconductor layer 176, and a portion of the lower sacrificial layer 320 are etched to form a word line cut opening 180H, and a cover insulating layer 330 is formed to cover the sidewall of the word line cut opening 180H. In an exemplary embodiment, the cover insulating layer 330 covers all the sidewalls of the plurality of sacrificial layers 310 exposed by the word line cut opening 180H and exposes the sidewall of the lower sacrificial layer 320. For example, the cover insulating layer 330 is formed using a material that does not have good step coverage characteristics, so that the cover insulating layer 330 is not formed on the bottom of the word line cut opening 180H and on the upper surface of the substrate 110.

[0102] 35 and 36, the lower sacrificial layer 320 (FIG. 34) exposed at the bottom of the word line cut opening 180H is removed, and a lower opening 174H is formed at the position where the lower sacrificial layer 320 was removed. The sidewall of the gate insulating layer 132C is exposed through the lower opening 174H. In an exemplary embodiment, the process of removing the lower sacrificial layer 320 may be a wet etching process using a phosphoric acid solution as an etchant.

[0103] 37, a portion of the gate insulating layer 132C exposed by the lower opening 174H is removed to expose a sidewall of the channel layer 142. The process of removing the gate insulating layer 132C is a wet etching process. In the wet etching process, a portion of the gate insulating layer 132C disposed between the channel layer 142 and the second semiconductor layer 176 is exposed by the lower opening 174H and removed together, and a portion of the gate insulating layer 132C disposed between the channel layer 142 and the lowermost first insulating layer 120 is exposed by the lower opening 174H and removed together. However, the technical idea of ​​the present invention is not limited thereto.

[0104] 38, the inside of the word line cut opening 180H (FIG. 35) and the inside of the lower opening 174H are filled with a first semiconductor layer 174. The first semiconductor layer 174 is formed to fill the inside of the lower opening 174H between the substrate 110 and the second semiconductor layer 176 and to contact the sidewall C140S of the channel structure C140C.

[0105] Then, a portion of the first semiconductor layer 174 formed on the inner wall of the word line cut opening 180H is removed by an etch-back process, so that the upper surface of the substrate 110 is exposed again at the bottom of the word line cut opening 180H.

[0106] Thereafter, the multiple sacrificial layers 310 (Figure 24) exposed by the word line cut openings 180H are removed, and multiple gate spaces 130GS are formed at the positions where the multiple sacrificial layers 310 have been removed, and preliminary gate electrode layers 130P are formed on the inner walls of the multiple gate spaces 130GS.

[0107] Thereafter, the steps described with reference to FIGS. 27 to 30 are carried out to complete the semiconductor device 100C.

[0108] As described above, exemplary embodiments have been disclosed in the drawings and the specification. Although specific terms have been used in the description of the embodiments, these terms are merely used for the purpose of describing the technical ideas of the present invention, and are not used to limit the meaning or the scope of the present invention described in the claims. Therefore, a person skilled in the art will understand that various modifications and equivalent other embodiments are possible. Therefore, the true technical scope of protection of the present invention should be determined by the technical ideas of the claims. [Industrial Applicability]

[0109] The present invention is applicable, for example, to technical fields related to memory devices. [Explanation of symbols]

[0110] 100 Semiconductor device 130 Gate electrode 132 Gate Insulation Layer C140 Channel Structure 142 Channel Layer 144 Charge storage structure 146 Body Gate Layer 150 bit line pad 164 bit lines 168 Body Gate Line

Claims

1. a channel structure disposed on a substrate and extending in a first direction perpendicular to an upper surface of the substrate, the channel structure including a body gate layer extending in the first direction, a charge storage structure surrounding a sidewall of the body gate layer, and a channel layer surrounding a sidewall of the charge storage structure; a plurality of gate electrodes disposed on the substrate and spaced apart in the first direction on sidewalls of the channel structure; a gate insulating layer disposed between each of the plurality of gate electrodes and the channel structure; the channel layer is disposed on an inner wall of a channel hole extending in the first direction through the plurality of gate electrodes, and the body gate layer fills the inside of the channel hole on the charge storage structure.

2. the charge storage structure is disposed between the body gate layer and the channel layer; The device of claim 1 , wherein the charge storage structure contacts an inner wall of the channel layer.

3. A semiconductor device as described in claim 1 or 2, characterized in that the charge storage structure is conformally arranged on the channel layer along the inner wall of the channel hole.

4. The charge storage structure comprises: a blocking dielectric layer disposed on the sidewalls of the body gate layer; a charge storage layer disposed on the blocking dielectric layer; 2. The device of claim 1, further comprising: a tunneling dielectric layer formed on the charge storage layer and in contact with the channel layer.

5. the channel layer includes a bottom portion in contact with a top surface of the substrate; 3. The semiconductor device of claim 1, wherein the entire bottom surface of the charge storage structure is covered by the channel layer, and the bottom surface of the charge storage structure is not in contact with the substrate.

6. Each of the gate electrodes further includes a plurality of insulating layers disposed between two adjacent gate electrodes of the plurality of gate electrodes; the gate insulating layer covers an upper surface and a lower surface of each of the gate electrodes; 6. The semiconductor device according to claim 1, wherein the insulating layers are in contact with the sidewalls of the channel structure.

7. Each of the gate electrodes further includes a plurality of insulating layers disposed between two adjacent gate electrodes of the plurality of gate electrodes; the gate insulating layer is disposed only between each of the plurality of gate electrodes and the channel structure; 6. The semiconductor device according to claim 1, wherein the insulating layers are in contact with the sidewalls of the channel structure.

8. Each of the gate electrodes further includes a plurality of insulating layers disposed between two adjacent gate electrodes of the plurality of gate electrodes; the gate insulating layer has a portion extending in the first direction along the sidewall of the channel structure; 6. The semiconductor device according to claim 1, wherein the insulating layers are not in contact with the sidewall of the channel structure.

9. a bit line pad formed at a higher level than a top gate electrode of the plurality of gate electrodes and disposed on the channel layer, an inner side wall of the bit line pad defining an opening; a bit line contact connected to the bit line pad; 6. The semiconductor device according to claim 1, further comprising: a body gate contact passing through the opening and coupled to the body gate layer.

10. 10. The semiconductor device of claim 9, wherein in a plan view, the opening vertically overlaps the body gate layer, and the inner sidewall of the bit line pad surrounds the body gate layer.

11. a bit line connected to the bit line contact and extending in a second direction parallel to an upper surface of the substrate; 10. The semiconductor device of claim 9, further comprising: a body gate line connected to the body gate contact and extending in the second direction.

12. 12. The semiconductor device according to claim 1, wherein an upper surface of the body gate layer is disposed at the same level as an upper surface of the channel layer.

13. 12. The semiconductor device according to claim 1, wherein an upper surface of the body gate layer is located at a lower level than an upper surface of the channel layer.

14. 14. The semiconductor device of claim 1, further comprising a conductive barrier layer disposed between the body gate layer and the charge storage structure.

15. a plurality of gate electrodes disposed on a substrate and spaced apart in a first direction perpendicular to a top surface of the substrate; a channel structure disposed in a channel hole extending in the first direction through the plurality of gate electrodes, the channel structure including: a channel layer disposed on an inner wall of the channel hole; a charge storage structure disposed on the channel layer on the inner wall of the channel hole; and a body gate layer on the charge storage structure filling an interior of the channel hole; a gate insulating layer disposed between each of the plurality of gate electrodes and the channel layer, the gate insulating layer covering an upper surface and a bottom surface of each of the plurality of gate electrodes; The channel layer is disposed between each of the gate electrodes and the charge storage structure.

16. A semiconductor device as described in Claim 15, characterized in that the charge storage structure is conformally positioned on the channel layer along the inner wall of the channel hole.

17. a bit line pad formed at a higher level than a top gate electrode of the plurality of gate electrodes and disposed on the channel layer, an inner side wall of the bit line pad defining an opening; a bit line contact connected to the bit line pad; The semiconductor device of claim 16 , further comprising: a body gate contact passing through the opening and coupled to the body gate layer.

18. a bit line connected to the bit line contact and extending in a second direction parallel to an upper surface of the substrate; 18. The semiconductor device of claim 17, further comprising: a body gate line connected to the body gate contact and extending in the second direction.

19. the charge storage structure is disposed between the body gate layer and the channel layer; the channel layer includes a bottom portion in contact with a top surface of the substrate; 17. The semiconductor device of claim 16, wherein an entire bottom surface of the charge storage structure is covered by the channel layer, and the bottom surface of the charge storage structure is not in contact with the substrate.

20. A channel structure disposed on a substrate and extending in a first direction perpendicular to an upper surface of the substrate, the channel structure including a body gate layer extending in the first direction, a charge storage structure surrounding a sidewall of the body gate layer, and a channel layer surrounding a sidewall of the charge storage structure; a plurality of gate electrodes disposed on the substrate and spaced apart in the first direction on sidewalls of the channel structure; a gate insulating layer disposed between each of the plurality of gate electrodes and the channel structure; a bit line pad formed at a level higher than a top gate electrode among the plurality of gate electrodes and disposed on the channel layer; a bit line contact connected to the bit line pad; a bit line connected to the bit line contact and extending in a second direction parallel to an upper surface of the substrate.

Images