Method of manufacturing magnetic memory device

Abstract

A method of manufacturing a magnetic memory device may include sequentially forming a first magnetic layer, a tunnel barrier layer, and a second magnetic layer on a substrate; performing a first etching process of sequentially etching the second magnetic layer, the tunnel barrier layer, and the first magnetic layer to form a magnetic tunnel junction pattern and an etching residual layer on a side surface of the magnetic tunnel junction pattern; performing a second etching process to remove at least a portion of the etch residual layer; and after the second etching process, performing a third etching process to remove a remaining portion of the etching residual layer. The third etching process may include: supplying a neutral gas onto the etch residual layer; and irradiating the first ion beam at a first inclination angle with respect to the top surface of the substrate.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10 - 2024 - 0013395, filed with the Korean Intellectual Property Office on January 29, 2024, the entire contents of which are incorporated herein by reference. Technical field

[0003] The present disclosure relates to a method of manufacturing a magnetic storage device. Background art

[0004] As the demand for faster and / or lower - power - consuming electronic devices continues to grow, the demand for semiconductor memory devices with faster operation speeds and / or lower operation voltages is also increasing. Magnetic storage devices have been proposed as semiconductor memory devices that can meet this demand. Due to their high - speed operation and / or non - volatility, magnetic storage devices are becoming the next - generation semiconductor memory devices. Generally, a magnetic storage device includes a magnetic tunnel junction (MTJ) pattern. The MTJ pattern includes two magnetic layers and an insulating layer therebetween. The resistance of the MTJ pattern can vary according to the magnetization directions of the magnetic layers. For example, when the magnetization directions of the magnetic layers are antiparallel to each other, the resistance of the MTJ pattern is higher than when the magnetization directions of the magnetic layers are parallel to each other. This resistance difference can be used for data write / read operations of the magnetic storage device. With the development of the electronics industry, the demand for magnetic storage devices with high integration density and / or low - power - consumption characteristics is increasing day by day, and in addition, many studies are being conducted to improve the reliability of magnetic storage devices. Summary of the invention

[0005] Embodiments of the inventive concept provide a method of manufacturing a magnetic storage device with improved reliability.

[0006] According to an embodiment of the inventive concept, a method of manufacturing a magnetic storage device may include: sequentially forming a first magnetic layer, a tunnel barrier layer, and a second magnetic layer on a substrate; performing a first etching process of sequentially etching the second magnetic layer, the tunnel barrier layer, and the first magnetic layer to form a magnetic tunnel junction pattern and an etched - residue layer on a side surface of the magnetic tunnel junction pattern; performing a second etching process to remove at least a part of the etched - residue layer; and after the second etching process, performing a third etching process to remove the remaining part of the etched - residue layer. The third etching process may include: supplying a neutral gas onto the etched - residue layer; and irradiating a first ion beam at a first tilt angle with respect to a top surface of the substrate.

[0007] According to an embodiment of the inventive concept, a method of manufacturing a magnetic storage device may include: sequentially forming a first magnetic layer, a tunnel barrier layer, and a second magnetic layer on a substrate; performing a first etching process of sequentially etching the second magnetic layer, the tunnel barrier layer, and the first magnetic layer to form a magnetic tunnel junction pattern and an etched residual layer on a side surface of the magnetic tunnel junction pattern; performing a second etching process to remove at least a part of the etched residual layer; and after the second etching process, performing a third etching process to remove a remaining part of the etched residual layer. The first etching process, the second etching process, and the third etching process may include a first ion beam etching process, a second ion beam etching process, and a third ion beam etching process, respectively. The third etching process may further include supplying a neutral gas onto the etched residual layer, and supplying the neutral gas and the third ion beam etching process may be performed simultaneously.

[0008] According to an embodiment of the inventive concept, a method of manufacturing a magnetic storage device may include: sequentially forming a first magnetic layer, a tunnel barrier layer, and a second magnetic layer on a substrate; performing a first etching process of sequentially etching the second magnetic layer, the tunnel barrier layer, and the first magnetic layer to form a magnetic tunnel junction pattern and an etched residual layer on a side surface of the magnetic tunnel junction pattern; performing a second etching process to remove at least a part of the etched residual layer; and performing a third etching process after the second etching process to remove a remaining part of the etched residual layer. The first etching process, the second etching process, and the third etching process may include a first ion beam etching process, a second ion beam etching process, and a third ion beam etching process, respectively. The third etching process may further include supplying a neutral gas onto the etched residual layer, and the first etching process, the second etching process, and the third etching process may be performed in the same process chamber. A vacuum pump connected to the process chamber may be operated during supplying the neutral gas and the third ion beam etching process. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 is a circuit diagram showing a unit storage cell of a magnetic storage device according to an embodiment of the inventive concept.

[0010] Figure 2A is a plan view showing a magnetic storage device according to an embodiment of the inventive concept.

[0011] Figure 2B is along Figure 2A sectional view taken along line I-I'.

[0012] Figure 3 is a schematic view showing a substrate processing apparatus for a process of operating with an ion beam and for manufacturing a magnetic storage device according to an embodiment of the inventive concept.

[0013] Figure 4Ais a flowchart showing a process of manufacturing a magnetic storage device according to an embodiment of the inventive concept.

[0014] Figure 4B is showing Figure 4A a flowchart of operation S4.

[0015] Figures 5A to 5F is a cross-sectional view taken along line I-I' for showing a method of manufacturing a magnetic storage device according to an embodiment of the inventive concept. Figure 2A

[0016] Figures 6A to 6C is a conceptual diagram showing a process of removing Figure 5D and Figure 5E etching residues shown in

[0017] Figures 7A to 7C is a conceptual diagram showing a process of removing Figure 5D and Figure 5E etching residues shown in DETAILED DESCRIPTION

[0018] Example embodiments of the inventive concept will now be described more fully with reference to the accompanying drawings, in which like reference numerals refer to like elements throughout. In the following drawings, for the sake of clarity, the thickness or size of each layer is exaggerated and thus the thickness or size of each layer may be slightly different from the actual shape and ratio. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. It should be noted that aspects described for one embodiment may be incorporated into different embodiments, although not specifically described herein. That is, the features of all embodiments and / or any embodiments may be combined in any way and / or combination.

[0019] Figure 1 is a circuit diagram of a unit storage cell of a magnetic storage device according to an embodiment of the inventive concept.

[0020] Referring to Figure 1 , the unit storage cell MC may include a storage element ME and a selection element SE. The storage element ME and the selection element SE may be electrically connected in series with each other. The storage element ME may be disposed between and connected to the bit line BL and the selection element SE. The selection element SE may be disposed between and connected to the storage element ME and the source line SL, and may be controlled by the word line WL. The selection element SE may include, for example, a bipolar transistor or a metal oxide semiconductor (MOS) field effect transistor.

[0021] ​The storage element ME may include a magnetic tunnel junction pattern MTJ, and the magnetic tunnel junction pattern MTJ may include a first magnetic pattern MP1, a second magnetic pattern MP2, and a tunnel barrier pattern TBP between the first magnetic pattern MP1 and the second magnetic pattern MP2. One of the first magnetic pattern MP1 and the second magnetic pattern MP2 may be a reference magnetic pattern having a fixed magnetization direction regardless of the presence of an external magnetic field generated in a typical usage environment. The other of the first magnetic pattern MP1 and the second magnetic pattern MP2 may be a free magnetic pattern whose magnetization direction may be changed to one of two stable magnetization directions by an external magnetic field. When the magnetization directions of the reference magnetic pattern and the free magnetic pattern are antiparallel to each other, the resistance of the magnetic tunnel junction pattern MTJ may be much larger than when they are parallel to each other. This means that the resistance of the magnetic tunnel junction pattern MTJ can be controlled by changing the magnetization direction of the free magnetic pattern. Therefore, the resistance difference of the magnetic tunnel junction pattern MTJ caused by the magnetization direction difference between the reference magnetic pattern and the free magnetic pattern can be used to change the data stored in the storage element ME of a unit memory cell MC.

[0022] Figure 2A is a plan view showing a magnetic storage device according to an embodiment of the inventive concept. Figure 2B is a cross-sectional view taken along line I-I' of Figure 2A .

[0023] Referring to Figure 2A and Figure 2B , a substrate 100 may be provided. In the present specification, a first direction D1 may be parallel to a top surface 100U of the substrate 100. A second direction D2 may be parallel to the top surface 100U of the substrate 100 and may be perpendicular to the first direction D1. A third direction D3 may be perpendicular to the top surface 100U of the substrate 100.

[0024] The substrate 100 may be a semiconductor substrate formed of or including silicon (Si), silicon germanium (SiGe), germanium (Ge), and / or gallium arsenide (GaAs), or may be a silicon-on-insulator (SOI) wafer. A select element (not shown) may be provided on the substrate 100. The select element may be a field effect transistor or a diode. The select element may be connected to the word line WL of Figure 1 . Each of the lower interconnects 102 may be electrically connected to a terminal (e.g., a drain terminal) of a corresponding select element in the select elements through a corresponding lower contact in the lower contacts 104.

[0025] A lower insulating layer may be provided on the substrate 100. The lower insulating layer may include a first interlayer insulating layer 106, an etch stop layer 105, and a second interlayer insulating layer 110. The second interlayer insulating layer 110 may be provided on the first interlayer insulating layer 106. The etch stop layer 105 may be provided between the first interlayer insulating layer 106 and the second interlayer insulating layer 110. Each of the first interlayer insulating layer 106 and the second interlayer insulating layer 110 may be formed of or include an oxide, a nitride, and / or an oxynitride material. Each of the first interlayer insulating layer 106 and the second interlayer insulating layer 110 may be formed of or include tetraethyl orthosilicate (TEOS). The etch stop layer 105 may include a material different from that of the first interlayer insulating layer 106 and the second interlayer insulating layer 110. The etch stop layer 105 may include a material having an etch selectivity with respect to the first interlayer insulating layer 106 and the second interlayer insulating layer 110. The etch stop layer 105 may be formed of or include one or more nitride materials (e.g., silicon nitride).

[0026] The lower interconnect structure 102 / 104 may be provided on the substrate 100. The lower interconnect structure 102 / 104 may be provided in the first interlayer insulating layer 106. The lower interconnect structure 102 / 104 may include lower interconnect lines 102 vertically (e.g., in a third direction D3) spaced apart from the substrate 100, and lower contacts 104 connected to the lower interconnect lines 102. The lower interconnect lines 102 may be spaced apart from the top surface 100U of the substrate 100 in the third direction D3. The lower contacts 104 may be provided between the substrate 100 and the lower interconnect lines 102, and each lower interconnect line 102 may be electrically connected to the substrate 100 through a corresponding one of the lower contacts 104. The lower interconnect lines 102 and the lower contacts 104 may be formed of or include one or more metal materials (e.g., copper).

[0027] The lower contact plug 150 may be provided to penetrate or extend through the second interlayer insulating layer 110 and the etch stop layer 105, and may be electrically connected to the substrate 100. The lower contact plug 150 may be electrically connected to the uppermost one of the lower interconnect lines 102, and may be electrically connected to a terminal of a select element (e.g., a source / drain terminal). The top surface of the lower contact plug 150 may be located at a height higher than the recessed top surface 110U of the second interlayer insulating layer 110 (e.g., in the third direction D3). The lower contact plug 150 may be formed of or include a doped semiconductor material (e.g., doped silicon), a metal material (e.g., tungsten, titanium, and / or tantalum), a metal-semiconductor compound (e.g., metal silicide), and / or a conductive metal nitride material (e.g., titanium nitride, tantalum nitride, and / or tungsten nitride).

[0028] The data storage structure DS may be disposed on the second lower interlayer insulating layer 110. When viewed in plan view, the data storage structure DS may be two-dimensionally arranged along a first direction D1 and a second direction D2. The data storage structure DS may be respectively connected to the second lower contact plug 120. Each data storage structure DS may include a bottom electrode BE, a magnetic tunnel junction pattern MTJ, and a top electrode TE. The bottom electrode BE may be in contact with each second lower contact plug 120. In an embodiment, the bottom electrode BE may be formed of or include one or more conductive metal nitride materials (e.g., TiN or TaN). The magnetic tunnel junction pattern MTJ may be disposed between the bottom electrode BE and the top electrode TE. The top electrode TE may be formed of a metal material (e.g., Ta, W, Ru, and Ir) and / or a conductive metal nitride material (e.g., TiN and TaN) or include a metal material and / or a conductive metal nitride material. The magnetic tunnel junction pattern MTJ may include a first magnetic pattern MP1, a second magnetic pattern MP2, and a tunnel barrier pattern TBP between the first magnetic pattern MP1 and the second magnetic pattern MP2. The first magnetic pattern MP1 may be disposed between the bottom electrode BE and the tunnel barrier pattern TBP, and the second magnetic pattern MP2 may be disposed between the top electrode TE and the tunnel barrier pattern TBP. In an embodiment, the tunnel barrier pattern TBP may include a magnesium oxide layer, a titanium oxide layer, an aluminum oxide layer, a magnesium zinc oxide layer, and / or a magnesium boride layer.

[0029] The upper insulating layer may be disposed on the data storage structure DS and may at least partially cover the data storage structure DS. The upper insulating layer may include a protective insulating layer 170 and an upper interlayer insulating layer 180.

[0030] The upper interlayer insulating layer 180 may be disposed on the second lower interlayer insulating layer 110. The upper interlayer insulating layer 180 may at least partially fill the space between the data storage structures DS. The upper interlayer insulating layer 180 may be formed of or include an oxide, a nitride, and / or an oxynitride material.

[0031] The protective insulating layer 170 may be interposed between the side surfaces of each data storage structure DS and the upper interlayer insulating layer 180 and may extend into the space between the recessed top surface 110U of the second lower interlayer insulating layer 110 and the upper interlayer insulating layer 180. The protective insulating layer 170 may include a material having an etching selectivity with respect to the upper interlayer insulating layer 180 and the second lower interlayer insulating layer 110. For example, the upper interlayer insulating layer 180 and the second lower interlayer insulating layer 110 may be formed of or include silicon oxide, and the protective insulating layer 170 may be formed of or include silicon nitride.

[0032] The upper interconnect line 200 may be disposed on the upper interlayer insulating layer 180 and may be connected to the top electrode TE. The upper interconnect line 200 may extend in the second direction D2. The upper interconnect line 200 may be connected to the magnetic tunnel junction pattern MTJ through the top electrode TE and may be used as Figure 1 the bit line BL. The upper interconnect line 200 may be formed of a metal material (e.g., copper) and / or a conductive metal nitride material or may include a metal material and / or a conductive metal nitride material.

[0033] Figure 3 FIG. is a schematic view of a substrate processing apparatus that uses an ion beam operation and is used for manufacturing a magnetic storage device according to an embodiment of the inventive concept.

[0034] Referring to Figure 3 , a substrate processing apparatus A may be provided. The substrate processing apparatus A may be a device configured to process a substrate using an ion beam. For example, the substrate processing apparatus A may be configured to perform an etching process on a substrate using an ion beam. In the present specification, the term "substrate" may refer to a silicon wafer, but the embodiments of the inventive concept are not limited thereto. The substrate processing apparatus A may include an ion beam source chamber 3, a process chamber 1, a substrate holder 9, a first gas supply part GS1, a second gas supply part GS2, and a vacuum pump VP.

[0035] The ion beam source chamber 3 may be configured to generate an ion beam. More specifically, the ion beam may be composed of ions extracted from a plasma by the ion beam source chamber 3. The ion beam emitted from the ion beam source chamber 3 may be incident on the process chamber 1. The ion beam may be used to process a substrate. To this end, the ion beam source chamber 3 may include a plasma chamber 31, a plasma generator 33, a grid 35, and a grid driving device.

[0036] The plasma chamber 31 may be configured to provide a plasma generation space 3h. The plasma generation space 3h may be connected to the first gas supply part GS1. In the plasma generation space 3h, a plasma may be generated from a part of the gas supplied from the first gas supply part GS1.

[0037] The plasma generator 33 may be coupled to the plasma chamber 31. The plasma generator 33 may be configured to generate plasma in the plasma generation space 3h. To this end, the plasma generator 33 may include an RF coil. The RF coil may be provided to surround the plasma chamber 31. The RF coil may be used to generate an electric field and / or a magnetic field in the plasma generation space 3h. In this case, the plasma may be generated from a part of the gas supplied to the plasma generation space 3h. In other words, the plasma may be generated in the plasma generation space 3h in the form of inductively coupled plasma (ICP). However, embodiments of the inventive concept are not limited to this example, and in an embodiment, the plasma generator 33 may be configured to include a device different from the RF coil.

[0038] The grid 35 may be connected to the plasma chamber 31. The grid 35 may be configured to extract ions from the plasma in the plasma generation space 3h. In an embodiment, a plurality of grids 35 may be provided. For example, a first grid 35a, a second grid 35b, and a third grid 35c may be provided, as Figure 3 shown. Each of the first grid 35a, the second grid 35b, and the third grid 35c may have a plate-like structure. For example, each of the first grid 35a, the second grid 35b, and the third grid 35c may be in the shape of a circular plate. The ions extracted from the plasma in the plasma generation space 3h may sequentially pass through the first grid 35a, the second grid 35b, and the third grid 35c, and may move into the process chamber 1. The third grid 35c may be grounded. For example, the third grid 35c may be a ground grid. The second grid 35b may be a screen grid. In an embodiment, the second grid 35b may be used to adjust the amount of ions passing through it. The first grid 35a may be an acceleration grid. The ion beam may be accelerated by the potential difference between the third grid 35c and the first grid 35a, and may be incident on the process target substrate WF.

[0039] The first gas supply part GS1 may be connected to the plasma generation space 3h. The first gas supply part GS1 may be configured to supply a plasma generation gas to the plasma chamber 31. In an embodiment, the plasma generation gas may include an inert gas (e.g., argon (Ar) gas). To this end, the first gas supply part GS1 may include a gas tank, a compressor, and a valve.

[0040] The process chamber 1 may be configured to provide a process space 1h. Processing may be performed on a process target substrate WF in the process space 1h. The process chamber 1 may be connected to an ion beam source chamber 3. For example, the ion beam source chamber 3 may be coupled to a side portion of the process chamber 1. The plasma generation space 3h and the process space 1h may be connected to each other through a grid 35. However, embodiments of the inventive concept are not limited to this example, and in an embodiment, the process chamber 1 may be arranged to surround the ion beam source chamber 3. In other embodiments, the process chamber 1 and the ion beam source chamber 3 may be arranged to be spaced apart from each other.

[0041] The substrate support part 5 may include a substrate holder 51 and a substrate holder adjusting device 55.

[0042] The substrate holder 51 may be placed in the process chamber 1. The substrate holder 51 may be spaced apart from the ion beam source chamber 3. For example, the substrate holder 51 may be spaced apart from the ion beam source chamber 3 in a downward direction, as Figure 3 shown. The substrate holder 51 may fasten the substrate to a specific position in the process space 1h. To this end, the substrate holder 51 may include an electrostatic chuck (ESC) and / or a vacuum chuck. However, embodiments of the inventive concept are not limited to this example, and the process target substrate WF may be set on the substrate holder 51 without additional fastening force.

[0043] The substrate holder adjusting device 55 may be configured to change the tilt angle of the substrate holder 51 and / or rotate the substrate holder 51. To this end, the substrate holder adjusting device 55 may include an actuator (e.g., a motor). The substrate driving device SD may be configured to change the tilt angle of the substrate support part 5 or rotate the substrate support part 5. More specifically, the substrate driving device SD may be configured to adjust the tilt angle of the substrate holder adjusting device 55 and apply rotational power to the substrate holder adjusting device 55, and in this case, the substrate holder adjusting device 55 may be used to change the tilt angle of the substrate holder 51 or rotate the substrate holder 51.

[0044] The second gas supply part GS2 may be connected to the process space 1h. The second gas supply part GS2 may be configured to supply a process gas into the process chamber 1. In an embodiment, the process gas may be an electrically neutral gas. For example, the neutral gas may include alcohol (e.g., CH3OH). To this end, the second gas supply part GS2 may include a gas tank, a compressor, and a valve.

[0045] The vacuum pump VP may be connected to the process space 1h. During this process, the vacuum pump VP may maintain the process space 1h in a substantially vacuum state. The vacuum pump VP may operate during the supply of the plasma generation gas and the process gas.

[0046] Figure 4Ais a flowchart showing a method of manufacturing a magnetic storage device according to an embodiment of the inventive concept. Figure 4B is a flowchart showing Figure 4A operation S4. Figures 5A to 5F is a cross-sectional view taken along line I-I' of Figure 2A showing a method of manufacturing a magnetic storage device according to an embodiment of the inventive concept.

[0047] Referring to Figure 4A and Figure 5A a magnetic tunnel junction (MTJ) layer (MTJL) can be formed on a substrate 100 (in S1). First, the substrate 100 can be prepared. Figure 3 A select element SE of

[0048] Referring to Figure 3 , Figure 4A and Figure 5B the substrate 100 having the magnetic tunnel junction layer MTJL can be disposed in Figure 3On the substrate holder 51. Hereinafter, the substrate 100 on which the magnetic tunnel junction layer MTJL or the magnetic tunnel junction pattern MTJ is formed will be referred to as the process target substrate WF. In an embodiment, before forming the conductive mask pattern 190, the process target substrate WF may be placed in the substrate processing apparatus. The magnetic tunnel junction layer MTJL and the conductive mask pattern 190 may face the ion beam source chamber 3 and may be spaced apart from the ion beam source chamber 3 in an inclined shape. The substrate holder 51 may be configured to fix the process target substrate WF to a specific position. For example, the substrate holder 51 may be configured to fix the process target substrate WF to a specific position in the process space 1h using electrostatic force and / or vacuum pressure. The process target substrate WF provided on the substrate holder 51 may be spaced apart from the ion beam source chamber 3.

[0049] A first etching process may be performed to form the magnetic tunnel junction pattern MTJ from the magnetic tunnel junction layer MTJL (in Figure 4A S2). A first etching process may be performed to form the bottom electrode BE from the bottom electrode layer BEL. Specifically, Figure 3 a plasma generating gas may be supplied from the first gas supply part GS1 to the plasma chamber 31. The plasma generating gas may include one of argon (Ar), neon (Ne), xenon (Xe), krypton (Kr), helium (He), oxygen (O2), hydrogen (H2), and ammonia (NH3). In an embodiment, the plasma generating gas may be argon (Ar). The plasma may be generated by the plasma generator 33 from a part of the plasma generating gas in the plasma generating space 3h. Emitting an ion beam from the ion beam source chamber 3 may include extracting ions from the plasma using the grid 35. The ions may be supplied to the process space 1h through the grid 35. The ion beam may be incident on the process target substrate WF, and in this case, the magnetic tunnel junction layer MTJL and the bottom electrode layer BEL may be sequentially etched using the conductive mask pattern 190 as an etching mask to form the magnetic tunnel junction pattern MTJ and the bottom electrode BE.

[0050] During the first etching process, the first ion beam IB1 can be incident on the process target substrate WF or substrate 100 at a first tilt angle Θ1. The range of the first tilt angle Θ1 can be from 60° to 70°. In this specification, the tilt angle can be the angle between the top surface 100U of the substrate 100 and the ion beam, or the angle between the horizontal surface (i.e., the surface in the plane defined by the D1 and D2 directions) and the ion beam. The first ion beam IB1 can be accelerated by a first potential difference. The first potential difference can be greater than or equal to 1000V. In this specification, the potential difference can represent the potential difference between the third grid 35c and the first grid 35a. The second magnetic layer ML2, the tunnel barrier layer TBL, the first magnetic layer ML1, and the bottom electrode layer BEL can be etched sequentially to form a second magnetic pattern MP2, a tunnel barrier pattern TBP, a first magnetic pattern MP1, and a bottom electrode BE, respectively. After etching the magnetic tunnel junction layer MTJL and the bottom electrode layer BEL, the remaining portion of the conductive mask pattern 190 remaining on the magnetic tunnel junction pattern MTJ can be referred to as the top electrode TE. The top electrode TE, the second magnetic pattern MP2, the tunnel barrier pattern TBP, the first magnetic pattern MP1, and the bottom electrode BE can be referred to as the data storage structure DS. The top surface 110U of the second interlayer insulating layer 110 between the data storage structures DS can be recessed by the first etching process.

[0051] Etching residues EB may be generated during the first etching process. The magnetic tunnel junction pattern MTJ, the bottom electrode BE, and the top electrode TE may contain a large amount of metal material. Therefore, compared with the etching process on a silicon layer or an insulating layer, the etching process for forming the data storage structure DS may have a lower etching rate and a risk of generating a large amount of etching residues EB. The etching residues EB may remain on the side surface of the magnetic tunnel junction pattern MTJ to form an etching residue layer EBL. Since the etching residue layer EBL is redeposited, it can also be referred to as a redeposited layer. For example, the etching residues EB can be formed of or include a metal material. In the case where the etching residue layer EBL adheres to the side surface of the tunnel barrier pattern TBP, a short - circuit problem may occur between the first magnetic pattern MP1 and the second magnetic pattern MP2 during the operation of the magnetic storage device. During the first etching process, Figure 3 the vacuum pump VP can be continuously operated to discharge the removed etching residues EB to the outside of the chamber.

[0052] Referring to Figure 3 、 Figure 4A and Figure 5C ,a second etching process (in S3) can be performed on the etching residue layer EBL. At least a part of the etching residue layer EBL can be removed by the second etching process. The second etching process can be referred to as a trimming process. The plasma - generating gas can be from Figure 3The first gas supply part GS1 is supplied into the plasma chamber 31, and the plasma generating gas can be the same gas as that in the first etching process. For example, the plasma generating gas can contain argon (Ar). The second etching process can be performed in the same process chamber (i.e., process chamber 1) as the first etching process. During the second etching process, the second ion beam IB2 can be incident on the process target substrate WF or substrate 100 at a second tilt angle Θ2. The second tilt angle Θ2 of the second ion beam IB2 can be smaller than the first tilt angle Θ1 of the first ion beam IB1. For example, the range of the second tilt angle Θ2 can be from 30° to 50°. The ion beam IB can be accelerated by a second potential difference. The second potential difference can be smaller than the first potential difference. The second potential difference can be less than or equal to 300V. As an example, the range of the second potential difference can be from 20V to 300V. As another example, the range of the second potential difference can be from 200V to 300V. The second etching process can increase the recess depth of the top surface 110U of the second interlayer insulating layer 110 between the data storage structures DS. In the first etching process, the etching residue EB can adhere to the top surface 110U of the second interlayer insulating layer 110 between the data storage structures DS. Alternatively, during the second etching process, a part of the etching residue layer EBL can be separated from the side surface of the data storage structure DS and can adhere to the top surface 110U of the second interlayer insulating layer 110 between the data storage structures DS again. In the case where the etching residue layer EBL remains between adjacent data storage structures in the data storage structure DS, the adjacent data storage structures in the data storage structure DS may be inadvertently connected to each other. During the second etching process, the etching residue layer EBL may be partially removed from the side surface of the data storage structure DS and the top surface 110U of the second interlayer insulating layer 110 between the adjacent data storage structures DS. However, since the spacing between adjacent data storage structures in the data storage structure DS is small (e.g., less than 100nm), the etching residue layer EBL may not be sufficiently removed. During the second etching process, Figure 3 the vacuum pump VP can continuously operate to discharge the removed etching residue EB to the outside of the chamber.

[0053] Referring to Figure 3 , Figure 4A , Figure 4B , Figure 5C and Figure 5D , a third etching process can be performed to remove the etching residue layer. The third etching process can include supplying a neutral gas to the etching residue layer (in S41), and irradiating an ion beam to activate the neutral gas (in S42). Activating the neutral gas may mean forming a new compound, which is caused by the reaction between the neutral gas and the etching residue.

[0054] A neutral gas can be supplied from Figure 3 the second gas supply part GS2 to the process chamber 1. In an embodiment, the neutral gas can be an uncharged gas in which there are no positive charges or negative charges. The neutral gas can include organic compounds containing a hydroxyl group (-OH). The neutral gas can include methanol (CH3OH), ethanol (C2H5OH), acetic acid (CH3COOH), 1-propanol (CH3CH2CH2OH), 2-propanol (CH3CHOHCH3), butanol (C4H9OH), aminomethanol (NH2CH2OH), glycerol (C3H8O3), and / or ethylene glycol (C2H6O2). As Figure 5C shown, the neutral gas can be adsorbed and diffused onto the top surface and side surfaces of the data storage structure DS and onto the top surface 110U between adjacent data storage structures in the data storage structure DS of the second interlayer insulating layer 110 to form an adsorption layer 160. The adsorption layer 160 can be located on the remaining part of the etch residue layer EBL and at least partially cover the remaining part.

[0055] When gas is supplied from the second gas supply part GS2, a third ion beam IB3 can be incident from the ion beam source chamber 3 into the process target substrate WF or the substrate 100. The plasma generating gas can be supplied from Figure 3 the first gas supply part GS1 to the plasma chamber 31, and the plasma generating gas can be the same gas as the gas in the first etching process. For example, the plasma generating gas can contain argon. The third etching process can be performed in the same process chamber (i.e., the process chamber 1) as the first etching process. The third ion beam IB3 can be incident at a third tilt angle Θ3. The third tilt angle Θ3 can be less than the first tilt angle Θ1. For example, the range of the third tilt angle Θ3 can be from 30° to 50°. The ion beam IB can be accelerated by a third potential difference. The third potential difference can be less than the first potential difference. The third potential difference can be less than or equal to 300V. As an example, the range of the third potential difference can be from 100V to 300V. As another example, the range of the third potential difference can be from 200V to 300V. The third potential difference and the third tilt angle Θ3 associated with the third ion beam IB in the third etching process can be the same as or similar to the second potential difference and the second tilt angle Θ2 associated with the second ion beam IB2 in the second etching process. In an embodiment, the third etching process can be performed when the process space 1h of the process chamber 1 has an internal pressure in the range of 0.2 mT to 0.5 mT.

[0056] The adsorption layer 160 and the etch residue layer EBL can be further removed by a third etching process. In some embodiments, the adsorption layer 160 and the etch residue layer EBL can be completely removed. In other embodiments, a portion of the adsorption layer 160 and / or the etch residue layer EBL can be retained. Specifically, ions of the third ion beam IB3 (e.g., argon ions) can collide with the adsorption gas to activate the gas. Due to the reaction between the activated gas and the etch residue EB, the etch residue EB can be oxidized and replaced by the volatile material VM.

[0057] During the supply of the neutral gas and the irradiation of the third ion beam IB3, Figure 3 the vacuum pump VP can be continuously operated to discharge the unadsorbed and remaining neutral gas and the volatile material VM to the outside of the chamber.

[0058] According to an embodiment of the inventive concept, the irradiation of the third ion beam IB3 can be performed after the supply of the neutral gas.

[0059] Referring to Figure 5F , the protective insulating layer 170 can be formed on the second interlayer insulating layer 110. The protective insulating layer 170 can be conformally disposed on the top surface and the side surfaces of each data storage structure DS and at least partially cover the top surface and the side surfaces of each data storage structure DS, and can extend along the recessed top surface 110U of the second interlayer insulating layer 110. Next, the upper interlayer insulating layer 180 can be formed to at least partially fill the space between the data storage structures DS and cover the protective insulating layer 170 and the data storage structures DS.

[0060] Returning to the reference Figure 2B , the upper interlayer insulating layer 180 and the protective insulating layer 170 can be partially removed to expose the top surface of the top electrode TE. The partial removal of the upper interlayer insulating layer 180 and the protective insulating layer 170 can include performing a planarization process to expose the top surface of the top electrode TE. In an embodiment, the planarization process can include a chemical mechanical polishing (CMP) process or an etch-back process.

[0061] The upper interconnect 200 can be formed on the upper interlayer insulating layer 180. The upper interconnect 200 can be located on the exposed top surface of the top electrode TE and at least partially cover the exposed top surface. Accordingly, the upper interconnect 200 can be electrically connected to the top electrode TE.

[0062] Figures 6A to 6C is a conceptual diagram showing a process of removing Figure 5D and Figure 5E the etch residue shown in

[0063] Referring to Figure 5D and Figure 6A, the neutral gas NG can be adsorbed on the etching residue EB provided on the side surface of the tunnel barrier pattern TBP. For example, the etching residue EB can be titanium (Ti) particles. In an embodiment, the neutral gas NG can be methanol (CH3OH) gas.

[0064] Referring to Figure 5E and Figure 6B , the third ion beam IB3 can be irradiated onto the adsorbed neutral gas, and in this case, the energy of argon ions (Ar + ) can be provided to the adsorbed neutral gas. During this process, the O-H bond of methanol (CH3OH) may be broken, and H may be removed to form Ti-O-CH3 molecules. Some of the Ti-O-CH3 molecules may volatilize.

[0065] Referring to Figure 5E and Figure 6C , the third ion beam IB3 can be continuously irradiated to provide ion energy to the non-volatile Ti-O-CH3 molecules, and in this case, H may be removed to form Ti-O-C molecules. That is, the etching residue may be oxidized.

[0066] Figures 7A to 7C is a conceptual diagram showing the process of removing Figure 5D and Figure 5E the etching residue shown in

[0067] Referring to Figure 5D and Figure 7A , the neutral gas NG can be adsorbed on the etching residue EB provided on the side surface of the tunnel barrier pattern TBP. The etching residue EB can be, for example, tantalum (Ta) particles. The neutral gas NG can be, for example, methanol (CH3OH) gas.

[0068] Referring to Figure 5D and Figure 7B , the third ion beam IB3 can be irradiated onto the adsorbed neutral gas, and in this case, the energy of argon ions (Ar + ) can be provided to the adsorbed neutral gas. During this process, the CH3-OH bond of methanol (CH3OH) may be broken, and -OH may be removed to form Ta-CH3 molecules.

[0069] Referring to Figure 5E and Figure 6C , the third ion beam IB3 can be continuously irradiated, and in this case, the highly volatile Ta-CH3 molecules may be exposed to the energy of the ions and may volatilize.

[0070] According to an embodiment of the inventive concept, by adsorbing a neutral gas on an etch residue layer and activating the neutral gas using an ion beam, the etch residue can be effectively removed in whole or in part.

[0071] According to an embodiment of the inventive concept, the third etch process may be performed in the same process chamber as the first etch process and the second etch process. In addition, except for supplying a neutral gas, the third etch process may be performed under the same or similar conditions as the second etch process. Each of the first to third etch processes may be an ion beam etch process. Accordingly, the entire etch process can be effectively performed.

[0072] According to an embodiment of the inventive concept, in the third etch process, supplying the neutral gas and irradiating the third ion beam may be performed simultaneously. Accordingly, the etch process can be effectively performed compared to performing these operations separately. In addition, since the vacuum pump also operates simultaneously, the etch process can be effectively performed.

[0073] According to an embodiment of the inventive concept, in the third etch process, a gas containing an organic compound having a hydroxyl group may be supplied in a neutral state rather than in a radical or ionic form to perform an ion beam etch process. Accordingly, compared to a reactive ion etch (RIE) process in which a gas containing an organic compound having a hydroxyl group is supplied in a radical or ionic form, damage to the magnetic tunnel junction pattern can be prevented and an undesired by-product generated by reacting with the magnetic tunnel junction pattern can be prevented.

[0074] According to an embodiment of the inventive concept, since the second etch process is performed between the first etch process and the third etch process, the etch residue can be more effectively removed in the third etch process.

[0075] According to an embodiment of the inventive concept, in the third etch process, the ion beam may be irradiated at a third tilt angle smaller than the first tilt angle, and in this case, the etch residue can be effectively removed.

[0076] In a method of manufacturing a magnetic storage device according to an embodiment of the inventive concept, conductive etch residues generated during a process of forming a magnetic tunnel junction pattern can be effectively removed. Accordingly, the reliability of the magnetic storage device can be improved.

[0077] Although example embodiments of the inventive concept have been specifically shown and described, those of ordinary skill in the art will understand that changes in form and detail may be made therein without departing from the spirit and scope of the appended claims.

Claims

1. A method of manufacturing a magnetic storage device, comprising: sequentially forming a first magnetic layer, a tunnel barrier layer, and a second magnetic layer on a substrate; performing a first etching process of sequentially etching the second magnetic layer, the tunnel barrier layer, and the first magnetic layer to form a magnetic tunnel junction pattern and an etched residue layer on a side surface of the magnetic tunnel junction pattern; performing a second etching process to remove at least a part of the etched residue layer; and after the second etching process, performing a third etching process to remove a remaining part of the etched residue layer, wherein the third etching process comprises: supplying a neutral gas onto the etched residue layer; and irradiating a first ion beam at a first tilt angle with respect to a top surface of the substrate.

2. The method according to claim 1, wherein The neutral gas includes methanol CH3OH, ethanol C2H5OH, acetic acid CH3COOH, 1-propanol CH3CH2CH2OH, 2-propanol CH3CHOHCH3, butanol C4H9OH, aminomethanol NH2CH2OH, glycerol C3H8O3, ethylene glycol C2H6O2, or a combination thereof.

3. The method according to claim 1, wherein, The first etching process, the second etching process, and the third etching process are performed in the same process chamber.

4. The method according to claim 3, wherein Supplying the neutral gas further comprises adsorbing the neutral gas onto the etched residue layer.

5. The method according to claim 1, wherein The range of the first tilt angle is from 30° to 50°.

6. The method according to claim 1, wherein, The first ion beam is accelerated by a first potential difference, and wherein the first potential difference is less than or equal to 300V.

7. The method according to claim 1, wherein The first etching process comprises irradiating a second ion beam at a second tilt angle with respect to the top surface of the substrate, and wherein the second tilt angle is greater than the first tilt angle.

8. The method according to claim 7, wherein The range of the second tilt angle is from 60° to 70°.

9. The method according to claim 7, wherein The second ion beam is accelerated by a second potential difference, and wherein the second potential difference is greater than or equal to 1000V.

10. The method according to claim 1, wherein, Supplying the neutral gas and irradiating the first ion beam are performed simultaneously.

11. The method according to claim 1, wherein, Irradiating the first ion beam is performed after supplying the neutral gas.

12. A method of manufacturing a magnetic storage device, comprising: sequentially forming a first magnetic layer, a tunnel barrier layer, and a second magnetic layer on a substrate; performing a first etching process of sequentially etching the second magnetic layer, the tunnel barrier layer, and the first magnetic layer to form a magnetic tunnel junction pattern and an etched residue layer on a side surface of the magnetic tunnel junction pattern; performing a second etching process to remove at least a part of the etched residue layer; and after the second etching process, performing a third etching process to remove a remaining part of the etched residue layer, wherein the first etching process, the second etching process, and the third etching process respectively comprise a first ion beam etching process, a second ion beam etching process, and a third ion beam etching process, wherein the third etching process further comprises supplying a neutral gas onto the etched residue layer, and wherein supplying the neutral gas and the third ion beam etching process are performed simultaneously.

13. The method according to claim 12, wherein, The neutral gas includes methanol CH3OH, ethanol C2H5OH, acetic acid CH3COOH, 1-propanol CH3CH2CH2OH, 2-propanol CH3CHOHCH3, butanol C4H9OH, aminomethanol NH2CH2OH, glycerol C3H8O3, ethylene glycol C2H6O2, or a combination thereof.

14. The method according to claim 12, wherein, The first ion beam etching process includes irradiating a first ion beam onto the substrate at a first tilt angle with respect to the top surface of the substrate. Wherein, the second ion beam etching process includes irradiating a second ion beam onto the substrate at a second tilt angle with respect to the top surface of the substrate. Wherein, the third ion beam etching process includes irradiating a third ion beam onto the substrate at a third tilt angle with respect to the top surface of the substrate, and wherein, the second tilt angle and the third tilt angle are less than the first tilt angle.

15. The method according to claim 14, wherein, The range of the first tilt angle is from 60° to 70°, and wherein, the range of the second tilt angle and the third tilt angle is from 30° to 50°.

16. The method according to claim 14, wherein The first ion beam is accelerated by a first potential difference. Wherein, the second ion beam is accelerated by a second potential difference. Wherein, the third ion beam is accelerated by a third potential difference, and wherein, the second potential difference and the third potential difference are less than the first potential difference.

17. The method according to claim 16, wherein, The first potential difference is greater than or equal to 1000V, and wherein, the second potential difference and the third potential difference are less than or equal to 300V.

18. A method of manufacturing a magnetic storage device, comprising: Sequentially forming a first magnetic layer, a tunnel barrier layer, and a second magnetic layer on a substrate; Performing a first etching process of sequentially etching the second magnetic layer, the tunnel barrier layer, and the first magnetic layer to form a magnetic tunnel junction pattern and an etched residue layer on a side surface of the magnetic tunnel junction pattern; Performing a second etching process to remove at least a portion of the etched residue layer; And After the second etching process, performing a third etching process to remove the remaining portion of the etched residue layer. Wherein, the first etching process, the second etching process, and the third etching process respectively include a first ion beam etching process, a second ion beam etching process, and a third ion beam etching process. Wherein, the third etching process further includes supplying a neutral gas onto the etched residue layer. Wherein, the first etching process, the second etching process, and the third etching process are performed in the same process chamber, and wherein, a vacuum pump connected to the process chamber operates during the supply of the neutral gas and the third ion beam etching process.

19. The method according to claim 18, wherein, The neutral gas includes methanol CH3OH, ethanol C2H5OH, acetic acid CH3COOH, 1-propanol CH3CH2CH2OH, 2-propanol CH3CHOHCH3, butanol C4H9OH, aminomethanol NH2CH2OH, glycerol C3H8O3, ethylene glycol C2H6O2, or a combination thereof.

20. The method according to claim 18, wherein, The supplied neutral gas is in an ion-free or radical-free state.

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