Sputtering apparatus and method of manufacturing magnetic memory device

Abstract

A sputtering apparatus and a method of manufacturing a magnetic memory device can be provided, the sputtering apparatus including: a chamber; a gas supply source configured to supply a first inert gas and a second inert gas to the chamber, the first inert gas and the second inert gas having first and second evaporation points, respectively, wherein the first evaporation point is higher than the second evaporation point; a plurality of sputtering guns in an upper portion of the chamber; a chuck in a lower portion of the chamber and facing the plurality of sputtering guns, the chuck configured to receive a substrate thereon; and a cooling unit connected to a lower portion of the chuck, the cooling unit configured to cool the chuck to a temperature lower than the first evaporation point and higher than the second evaporation point.

Description

Technical Field

[0001] The present invention relates to apparatus for manufacturing semiconductor devices and / or methods for manufacturing semiconductor devices using the apparatus, and more specifically, to sputtering apparatus and / or methods for manufacturing magnetic storage devices using the sputtering apparatus. Background Technology

[0002] As electronic products trend towards higher speeds and / or lower power consumption, there is an increasing demand for high speeds and low operating voltages for semiconductor memory devices integrated into these products. To meet these requirements, magnetic storage devices have been developed as semiconductor memory devices. Due to their relatively high operating speeds and non-volatile characteristics, magnetic storage devices have attracted considerable attention as next-generation semiconductor memory devices. Summary of the Invention

[0003] Some exemplary embodiments of the present invention provide sputtering apparatus and / or methods for manufacturing magnetic storage devices that can reduce surface roughness and improve the vertical magnetic anisotropy of magnetic metal layers.

[0004] According to some exemplary embodiments of the present invention, a sputtering apparatus may include: a chamber; a gas supply configured to supply a first inert gas and a second inert gas to the chamber, the first inert gas and the second inert gas having a first evaporation point and a second evaporation point, respectively, wherein the first evaporation point is higher than the second evaporation point; a plurality of sputtering guns in the upper part of the chamber; a chuck in the lower part of the chamber and facing the plurality of sputtering guns, the chuck being configured to receive a substrate thereon; and a cooling unit connected to the lower part of the chuck, the cooling unit being configured to cool the chuck to a temperature below the first evaporation point and above the second evaporation point.

[0005] According to some exemplary embodiments conceived in this invention, a sputtering apparatus may include: a chamber; a chuck, located in the lower portion of the chamber and loading a substrate; a cooling unit connected to the lower portion of the chuck, the cooling unit being configured to cool the chuck to a temperature below room temperature; a gas supply source configured to supply inert gas to the chamber; and a plurality of sputtering guns, located above the chuck and in the upper portion of the chamber. The plurality of sputtering guns may include a first sputtering gun on one side of the chuck and a second sputtering gun on the other side of the chuck, the second sputtering gun having nozzle orifices configured to eject inert gas.

[0006] According to some exemplary embodiments of the present invention, a method of manufacturing a magnetic storage device may include: forming a first magnetic metal layer on a substrate; forming a non-magnetic metal oxide layer on the first magnetic metal layer using a first sputtering process that keeps the substrate at room temperature or above room temperature; and forming a second magnetic metal layer on the non-magnetic metal oxide layer using a second sputtering process that cools the substrate to a temperature of 50K or lower. Attached Figure Description

[0007] Figure 1 A plan view is shown, illustrating an example of a sputtering apparatus according to an exemplary embodiment of a concept based on the present invention.

[0008] Figure 2 Show along Figure 1 A sectional view taken by line I-I'.

[0009] Figure 3 Show along Figure 1 The sectional view taken from line II-II'.

[0010] Figure 4 The graph shown illustrates the relationship between the roughness of the second magnetic metal layer and... Figure 1 The curve showing the relationship between the substrate temperature and the flow rate of the second inert gas.

[0011] Figure 5 A flowchart is shown, illustrating a method for manufacturing a magnetic storage device according to an exemplary embodiment of a concept based on the present invention.

[0012] Figures 6 to 14 A cross-sectional view is shown, illustrating a method for manufacturing a magnetic storage device according to an exemplary embodiment of the concept of the present invention.

[0013] Figure 15 The flowchart shows the formation Figure 9 An example of the steps for drawing the second magnetic metal layer.

[0014] Figure 16 The graph shown illustrates the relationship between perpendicular magnetic anisotropy and... Figure 9 The curve showing the relationship between the deposition temperature and thickness of the second magnetic metal layer is plotted in the figure.

[0015] Figure 17 A sectional view is shown, which shows Figure 11 Examples of the first vertical magnetic field in the first magnetic metal pattern and the second vertical magnetic field in the second magnetic pattern. Detailed Implementation

[0016] Although the terms “identical,” “equal,” or “the same” are used in the description of the exemplary embodiments, it should be understood that some imprecision may exist. Therefore, when an element is referred to as being identical to another element, it should be understood that the element or value is identical to the other element within the expected range of manufacturing or operational tolerances (e.g., ±10%).

[0017] When the terms “about” or “substantially” are used in conjunction with numerical values ​​in this specification, it is intended that the relevant numerical values ​​include manufacturing or operational tolerances (e.g., ±10%) near said numerical values. Furthermore, regardless of whether the numerical values ​​are modified to “about” or “substantially”, it will be understood that these values ​​should be interpreted as including manufacturing or operational tolerances (e.g., ±10%) near said numerical values ​​or shapes.

[0018] Figure 1 An example of a sputtering apparatus 100 according to an exemplary embodiment of the concept of the present invention is shown. Figure 2 Show along Figure 1 A sectional view taken by line I-I'.

[0019] Reference Figure 1 and Figure 2 According to an example embodiment of the present invention, a sputtering apparatus 100 may include a chamber 10, a chuck 20, a sputtering gun 30, a gas supply source 40, a power supply source 50, and a cooling unit 60.

[0020] Chamber 10 can provide a hermetically sealed space for housing the substrate W. For example, chamber 10 can be evacuated to approximately 1 × 10⁻⁶. -6 The high vacuum pressure of Torr. When chamber 10 is supplied with a first inert gas 46 or a second inert gas 48, chamber 10 can have a 1×10⁻⁶ vacuum pressure. -3 To about 1×10 -4 The low vacuum pressure of the chamber. Although not shown, multiple chambers 10 can be provided, and multiple chambers 10 can be connected in a cluster.

[0021] A chuck 20 may be disposed in the lower part of the chamber 10. The chuck 20 may hold a substrate W. The chuck 20 may electrostatically clamp or accommodate the substrate W using a voltage. A drive mechanism 22 may provide a rotational force to the chuck 20 to rotate the chuck 20 with the substrate W on it. The drive mechanism 22 may support the chuck 20. The drive mechanism 22 may include a shaft. The chuck 20 may have a coolant hole 24. The coolant hole 24 may be disposed on the top side of the chuck 20 and adjacent to the bottom surface of the substrate W. The chuck 20 may use a first coolant 72 in the coolant hole 24 to cool the substrate W. The first coolant 72 may include helium (He) gas.

[0022] The sputtering gun 30 may be positioned above the chuck 20 and in the upper part of the chamber 10. The sputtering gun 30 may generate a source for thin layers (e.g., metal layers and / or metal oxide layers). For example, the sputtering gun 30 may include a first sputtering gun 32, a second sputtering gun 34, a third sputtering gun 36, and a fourth sputtering gun 38.

[0023] The first sputtering gun 32 can be disposed on one side of the chuck 20. The first sputtering gun 32 can form a first non-magnetic metal layer on the substrate W using a first inert gas 46 and radio frequency power 52 (see...). Figure 6 (106). For example, the first sputtering gun 32 may include a first cathode 322, a first target 324, and a first shield 326. The first cathode 322 may use radio frequency power 52 to generate a first plasma P1 on the first target 324 using a first inert gas 46. Furthermore, the first cathode 322 may force the positive ions of the first inert gas 46 in the first plasma P1 to collide with the first target 324 to generate a source for the first nonmagnetic metal layer 106. The first target 324 may be disposed on the first cathode 322. The first target 324 may include a nonmagnetic rare earth metal. For example, the first target 324 may include ruthenium (Ru). The first shield 326 may surround the first target 324 and may protect the sidewalls of the first target 324 from the first plasma P1. The first shield 326 may include ceramic (e.g., Al2O3 and / or Y2O3).

[0024] The second sputtering gun 34 can be disposed on the other side of the chuck 20. The second sputtering gun 34 can form a first magnetic metal layer on the substrate W using a second inert gas 48 and radio frequency power 52 (see...). Figure 7 110) and the second magnetic metal layer (see 110) Figure 9(130). For example, the second sputtering gun 34 may include a second cathode 342, a second target 344, and a second shield 346. The second cathode 342 may use radio frequency power 52 to generate a second plasma P2 on the second target 344 using a second inert gas 48. Furthermore, the second cathode 342 may force positive ions of the second inert gas 48 in the second plasma P2 to collide with the second target 344 to generate a source for the first magnetic metal layer 110 and the second magnetic metal layer 130. The second target 344 may be disposed on the second cathode 342. For example, the second target 344 may include a magnetic metal (e.g., nickel (Ni), cobalt (Co), and / or iron (Fe)). The second shield 346 may be disposed on the outer edge of the second cathode 342 outside the second target 342. The second shield 346 may protect the sidewalls of the second target 344 from the second plasma P2. The second shield 346 may include ceramic (e.g., Al2O3 and / or Y2O3). The second shield 346 may have a nozzle orifice 348. Nozzle orifice 348 can be connected to a second gas supply source 44, which will be discussed below. A second target 344 can be supplied with a second inert gas 48 from nozzle orifice 348 in its vicinity, thus inducing a second plasma P2. The second plasma P2 can have a larger size than the first plasma P1. The second plasma P2 can have a higher density than the first plasma P1.

[0025] Figure 3 Show along Figure 1 The sectional view taken from line II-II'.

[0026] Reference Figure 3 The third sputtering gun 36 can be disposed on one side of the upper part of the chamber 10. The third sputtering gun 36 can form a non-magnetic metal oxide layer on the substrate W using the first inert gas 46 and radio frequency power 52 (see...). Figure 8 (120). For example, the third sputtering gun 36 may include a third cathode 362, a third target 364, and a third shield 366. The third cathode 362 may use radio frequency power 52 to generate a third plasma P3 of a first inert gas 46. The third plasma P3 may be different from the first plasma P1. The third cathode 362 may force positive ions in the third plasma P3 to collide with the third target 364 to generate a source for the nonmagnetic metal oxide layer 120. The third target 364 may be disposed on the third cathode 362. The third target 364 may include magnesium oxide (MgO). The third shield 366 may be disposed on the edge of the third cathode 362 outside the third target 364. The third shield 366 may protect the sidewalls of the third target 364 from the influence of the third plasma P3. The third shield 366 may include ceramic (e.g., Al2O3 and / or Y2O3).

[0027] The fourth sputtering gun 38 can be disposed on the other side of the upper part of the chamber 10. The fourth sputtering gun 38 can form a second non-magnetic metal layer on the substrate W using the first inert gas 46 and radio frequency power 52 (see...). Figure 10 (140). For example, the fourth sputtering gun 38 may include a fourth cathode 382, ​​a fourth target 384, and a fourth shield 386. The fourth cathode 382 may use radio frequency power 52 to generate a fourth plasma P4 of a first inert gas 46. The fourth plasma P4 may be the same as the first plasma P1 and the third plasma P3. The fourth target 384 may be disposed on the fourth cathode 382. The fourth target 384 may be a source of the second nonmagnetic metal layer 140 or may include a source of the second nonmagnetic metal layer 140. For example, the fourth target 384 may include a metal (e.g., tungsten (W), aluminum (Al), gold (Au), and / or silver (Ag)). The fourth shield 386 may surround the fourth target 384 and may protect the sidewalls of the fourth target 384 from the fourth plasma P4.

[0028] Return to reference Figure 2 The gas supply source 40 can supply one or more of a first inert gas 46 and a second inert gas 48 to the chamber 10. The first inert gas 46 and the second inert gas 48 can be supplied simultaneously or at different times. For example, the first inert gas 46 and the second inert gas 48 can be selectively supplied based on the temperature of the chuck 20 and the temperature of the substrate W. When the chuck 20 and the substrate W are at room temperature or a higher temperature than room temperature, the first inert gas 46 can be supplied to the chamber 10. When the chuck 20 and the substrate W are cooled by the cooling unit 60, the second inert gas 48 can be supplied to the chamber 10. The gas supply source 40 may include a first gas supply source 42 and a second gas supply source 44.

[0029] A first gas supply source 42 may be connected to the inner wall of chamber 10. The first gas supply source 42 may supply a first inert gas 46 to chamber 10. The first inert gas 46 may include, for example, argon (Ar). The first inert gas 46 may have an evaporation point of approximately 87.3 K. For example, the first gas supply source 42 may supply the first inert gas 46 at a flow rate between approximately 30 sccm and approximately 50 sccm.

[0030] The second gas supply source 44 can be connected to the nozzle orifice 348 in the second shield 346. The second gas supply source 44 can supply a second inert gas 48 to the nozzle orifice 348. The second inert gas 48 can have an atomic weight smaller than that of the first inert gas 46. The second inert gas 48 can include, for example, neon (Ne). The second inert gas 48 can have an evaporation point of about 27.7 K or lower. The second inert gas 48 can be supplied to the chamber 10 at a flow rate greater than that at which the first inert gas 46 is supplied to the chamber 10. For example, the second gas supply source 44 can supply the second inert gas 48 at a flow rate of about 200 sccm. If the second inert gas 48 is supplied at a flow rate less than about 200 sccm, the probability of electron collisions may be reduced, and therefore the second plasma P2 may not be generated properly.

[0031] A power supply 50 can be connected to a sputtering gun 30. The power supply 50 can supply radio frequency (RF) power 52 to the sputtering gun 30 to generate a first plasma P1, a second plasma P2, a third plasma P3, and a fourth plasma P4. The RF power 52 can be DC power, but the inventive concept is not limited thereto. The RF power 52 can be pulsed, and based on the frequency of the pulse, the RF power 52 can be classified as source power and bias power.

[0032] A cooling unit 60 may be disposed below the chuck 20. The cooling unit 60 may be coupled to or connected to the lower portion of the chamber 10. The cooling unit 60 can cool the chuck 20 and the substrate W on the chuck 20. For example, the cooling unit 60 can cool the chuck 20 and the substrate W to a temperature below the evaporation point of the first inert gas 46 (e.g., 87.3 K) and above the evaporation point of the second inert gas 48 (e.g., 27.7 K). The cooling temperature of the cooling unit 60 can be an extremely low temperature of about 50 K or lower. While the cooling unit 60 cools the chuck 20 and the substrate W, the second sputtering gun 34 can form a first magnetic metal layer 110 and a second magnetic metal layer 130 on the substrate W. When the cooling unit 60 cools the substrate W to an extremely low temperature, the second gas supply source 44 can supply a second inert gas 48 to the chamber 10. The second inert gas 48 can deposit the first magnetic metal layer 110 and the second magnetic metal layer 130 without condensation and / or freezing at the extremely low temperature. For example, when the first inert gas 46 is used to form the first magnetic metal layer 110 and the second magnetic metal layer 130, the first inert gas 46 may cause the first magnetic metal layer 110 and the second magnetic metal layer 130 to have increased deposition defects (e.g., surface roughness) caused by condensation at extremely low temperatures. Conversely, the second inert gas 48 can reduce the deposition defects (e.g., surface roughness) of the first magnetic metal layer 110 and the second magnetic metal layer 130.

[0033] Figure 4 The surface roughness of the second magnetic metal layer 130 is shown to be... Figure 1 The temperature of substrate W and Figure 1 The relationship curve between the flow rate of the second inert gas 48.

[0034] Reference Figure 4 The surface roughness of the second magnetic metal layer 130 can be reduced proportionally to the flow rate of the second inert gas 48 and the cooling temperature of the substrate W.

[0035] Reducing the flow rate of the second inert gas 48 can decrease the surface roughness of the second magnetic metal layer 130. For example, the first surface roughness G1 obtained by supplying the second inert gas 48 at a low flow rate of about 200 sccm can be less than the second surface roughness G2 obtained by supplying the second inert gas 48 at an intermediate flow rate of about 500 sccm and less than the third surface roughness G3 obtained by supplying the second inert gas 48 at a high flow rate of about 1000 sccm. The second surface roughness G2 can be obtained from the second magnetic metal layer 130 formed by supplying the second inert gas 48 at an intermediate flow rate of about 500 sccm. The third surface roughness G3 can be obtained from the second magnetic metal layer 130 formed by supplying the second inert gas 48 at a high flow rate of about 1000 sccm.

[0036] Lowering the temperature of the substrate W can reduce the surface roughness of the second magnetic metal layer 130. For example, the first surface roughness G1, the second surface roughness G2, and the third surface roughness G3 can be reduced proportionally to the cooling temperature of the substrate W (e.g., the amount of cooling). Based on the deposition temperature of the second magnetic metal layer 130 (e.g., 50K, 100K, and 300K), the first surface roughness G1 can be... and Based on the deposition temperature of the second magnetic metal layer 130 (e.g., 50K, 100K, and 300K), the second surface roughness G2 can be... and Based on the deposition temperature of the second magnetic metal layer 130 (e.g., 50K, 100K, and 300K), the third surface roughness G3 can be... and With approximately The second magnetic metal layer 130 of a certain thickness is used to measure surface roughness.

[0037] In one example embodiment, cooling unit 60 may include a cooler 62, a cooling link 64, a cooling head 66, and a coolant supply source 68. Cooler 62 may generate cold thermal energy. For example, cooler 62 may use a second coolant 74 to cool the cooling link 64, cooling head 66, and chuck 20. Cooler 62 may include, for example, a compressor 61 and an evaporator 63. Compressor 61 may compress and liquefy the second coolant 74. The second coolant 74 may include helium (He). Evaporator 63 may contact the bottom surface of the cooling link 64. Evaporator 63 may be connected to compressor 61. Evaporator 63 may evaporate the second coolant 74 and may use the heat of vaporization of the second coolant 74 to cool the cooling link 64 to an extremely low temperature of approximately 50 K or lower. The evaporated second coolant 74 may be directed back to compressor 61.

[0038] A cooling link 64 may be disposed between the cooler 62 and the chuck 20. The cooling link 64 may be connected to the lower part of the chamber 10. The shaft of the drive mechanism 22 may pass through the cooling link 64 and be configured to rotate the chuck 20. The cooling link 64 may seal the drive mechanism 22 relative to the chamber 10. The cooling link 64 may transfer the thermal energy of the cooler 62 to the cooling head 66 and the chuck 20. The cooling link 64 may have, for example, a cavity 65 and a sealing member 70. The cavity 65 may be disposed at the center or central portion of the cooling link 64. The cavity 65 may be filled with a third coolant 76. The third coolant 76 may provide the cooling energy of the cooler 62 to the cooling head 66 without condensing at extremely low temperatures. The third coolant 76 may be the same as the first coolant 72 and the second coolant 74. For example, the third coolant 76 may include helium (He). The sealing member 70 may be disposed in the cavity 65. A sealing member 70 may be disposed on the outer periphery of the drive mechanism 22 within the cavity 65. The sealing member 70 may provide a first coolant 72 from the coolant supply source 68 to the drive mechanism 22. The first coolant 72 may be supplied to the chuck 20 via the drive mechanism 22.

[0039] A cooling head 66 can be disposed between the cooling link 64 and the chuck 20. The cooling head 66 can provide the chuck 20 with the cooling energy from the cooler 62 and the cooling link 64. The cooling head 66 can be connected to the drive mechanism 22. When the drive mechanism 22 rotates, the cooling head 66 can rotate against the cooling link 64. The cooling head 66 may include a metal plate.

[0040] Coolant supply source 68 can supply first coolant 72 and third coolant 76 to cooling link 64 and chuck 20, respectively. For example, coolant supply source 68 may include first coolant supply source 67 and second coolant supply source 69. First coolant supply source 67 may be connected to cooling link 64. First coolant supply source 67 can supply third coolant 76 to cavity 65 to cool cooling link 64. Second coolant supply source 69 can supply first coolant 72 to coolant hole 24 through drive mechanism 22 and sealing member 70 in cavity 65, thereby cooling chuck 20 and substrate W. First coolant 72 in coolant hole 24 can provide the substrate W with the cooling energy of cooler 62 without condensation, thus cooling substrate W to an extremely low temperature equal to or below about 50K.

[0041] The method of manufacturing magnetic storage devices using the sputtering apparatus 100 configured as described above will now be discussed.

[0042] Figure 5 A method for manufacturing a magnetic storage device according to an exemplary embodiment of the concept of the present invention is shown. Figures 6 to 14 A cross-sectional view is shown, illustrating a method for manufacturing a magnetic storage device according to an exemplary embodiment of the concept of the present invention.

[0043] Reference Figure 5 and Figure 6 The first sputtering gun 32 can form a first nonmagnetic metal layer 106 on the substrate W using a room-temperature sputtering method or a high-temperature sputtering method (S10). A room-temperature sputtering method refers to a sputtering method that forms the layer while keeping the substrate W at or above room temperature. A high-temperature sputtering method refers to a sputtering method that forms the layer while heating the substrate W to a temperature above room temperature. For example, the first nonmagnetic metal layer 106 may include ruthenium (Ru). The substrate W may include a silicon wafer. An interlayer dielectric layer 102 and a contact plug 104 may be provided on the substrate W. The interlayer dielectric layer 102 may be formed between the substrate W and the first nonmagnetic metal layer 106. The interlayer dielectric layer 102 may include silicon oxide. The contact plug 104 may penetrate the interlayer dielectric layer 102 and may connect the first nonmagnetic metal layer 106 to the substrate W. Although not shown, the substrate W may have, for example, a switching element of a thin-film transistor and word lines connected to that switching element. The thin-film transistor may include a source electrode, a drain electrode, and a gate electrode. For example, the drain electrode can be connected to contact plug 104. The gate electrode can be connected to the word line.

[0044] Reference Figure 5 and Figure 7The second sputtering gun 34 can use an ultra-low temperature sputtering method to form a first magnetic metal layer 110 on the first non-magnetic metal layer 106 (S20). An ultra-low temperature sputtering method refers to a sputtering method that forms a layer when the substrate W is cooled to a temperature of 50K or lower. For example, the first magnetic metal layer 110 may include a ferromagnetic metal (e.g., nickel (Ni), cobalt (Co), and / or iron (Fe)) and impurities mixed in the ferromagnetic metal (e.g., boron (B)). The first magnetic metal layer 110 may include, for example, CoFeB, but the inventive concept is not limited thereto. The cooling unit 60 can cool the substrate W to an ultra-low temperature equal to or below about 50K to form the first magnetic metal layer 110. The first magnetic metal layer 110 may have approximately... to approximately The thickness. When the first magnetic metal layer 110 has approximately When the thickness is less than or equal to that of the first magnetic metal layer 110, the first magnetic metal layer 110 can have approximately Or even smaller surface roughness. In some example embodiments, the first magnetic metal layer 110 can be formed at room temperature or above room temperature using a room temperature sputtering method or a high temperature sputtering method.

[0045] Reference Figure 5 and Figure 8 The third sputtering gun 36 can form a non-magnetic metal oxide layer 120 on the first magnetic metal layer 110 using a room temperature sputtering method or a high temperature sputtering method (S30). The non-magnetic metal oxide layer 120 can be formed at room temperature or at a temperature above room temperature without low-temperature condensation of the coolant in the cooling unit 60. The non-magnetic metal oxide layer 120 can have, for example, approximately to approximately The thickness of the non-magnetic metal oxide layer 120 may include magnesium oxide (MgO), but the inventive concept is not limited thereto.

[0046] Reference Figure 5 and Figure 9 The second sputtering gun 34 can use a cryogenic sputtering method to form a second magnetic metal layer 130 on the non-magnetic metal oxide layer 120 (S40). The second magnetic metal layer 130 can be of the same type as the first magnetic metal layer 110. For example, the second magnetic metal layer 130 may include a ferromagnetic metal (e.g., nickel (Ni), cobalt (Co), and / or iron (Fe)) and impurities mixed in the ferromagnetic metal (e.g., boron (B)). The second magnetic metal layer 130 may include, for example, CoFeB.

[0047] Figure 15 Showing the formation Figure 9 An example of step S40 of the second magnetic metal layer 130 drawn in the figure.

[0048] Reference Figure 2, Figure 9 and Figure 15 The cooling unit 60 can cool the substrate W to an extremely low temperature (S42). The cooling unit 60 can cool the substrate W to an extremely low temperature equal to or lower than about 50K.

[0049] The second gas supply source 44 can supply the second inert gas 48 to the chamber 10 through the nozzle orifice 348 (S44). The second gas supply source 44 can supply the second inert gas 48 to the chamber 10 at a flow rate of about 200 sccm.

[0050] The power supply 50 can provide radio frequency power 52 to the second sputtering gun 34 to generate a second plasma P2 (S46). The radio frequency power 52 can be about 100W to about 200W. The second plasma P2 and the low-temperature substrate W can reduce the surface roughness of the second magnetic metal layer 130. In addition, the low-temperature substrate W can also reduce the surface energy of the second magnetic metal layer 130. The second magnetic metal layer 130 can be formed thinner than the first magnetic metal layer 110. For example, the second magnetic metal layer 130 can be formed with approximately Or even a thinner thickness.

[0051] Figure 16 Showing perpendicular magnetic anisotropy and Figure 9 The curve showing the relationship between the deposition temperature and thickness of the second magnetic metal layer 130 is plotted in the figure.

[0052] Reference Figure 16 , has about A second magnetic metal layer 130, or even a thinner layer, can have a perpendicular magnetic anisotropy that is inversely proportional to the deposition temperature of the second magnetic metal layer 130. For the second magnetic metal layer 130, a first perpendicular magnetic anisotropy G4 obtained at an extremely low temperature equal to or below about 50 K can be greater than a second perpendicular magnetic anisotropy G5 obtained at a low temperature equal to or below about 150 K, or a third perpendicular magnetic anisotropy G6 obtained at a room temperature of about 300 K. The second perpendicular magnetic anisotropy G5 can be obtained from a second magnetic metal layer 130 deposited at a low temperature of about 150 K. The third perpendicular magnetic anisotropy G6 can be obtained from a second magnetic metal layer 130 deposited at a room temperature of about 300 K. When the second magnetic metal layer 130 has approximately... At a thickness of [thickness value missing], the first perpendicular magnetic anisotropy G4 can have approximately 0.6 erg / cm. 3 The peak value. For example, the largest perpendicular magnetic anisotropy can be imparted at an extremely low temperature of about 50 K to form approximately A thick second magnetic metal layer of 130 mm. It has approximately... The second magnetic metal layer 130, or even thinner, can have approximately Or even smaller surface roughness.

[0053] Reference Figure 5 and Figure 10 The fourth sputtering gun 38 can form a second non-magnetic metal layer 140 on the second magnetic metal layer 130 using a room temperature sputtering method or a high temperature sputtering method (S50). The second non-magnetic metal layer 140 can be formed at room temperature or above room temperature. The second non-magnetic metal layer 140 may include a metal (e.g., gold (Au), silver (Ag), tungsten (W) and / or aluminum (Al)).

[0054] Reference Figure 5 and Figure 11 The photolithography and etching apparatus can partially remove the first non-magnetic metal layer 106, the first magnetic metal layer 110, the non-magnetic metal oxide layer 120, the second magnetic metal layer 130, and the second non-magnetic metal layer 140 to form a bottom electrode BE, a magnetic tunnel junction pattern MTJ, and a top electrode TE (S60). The magnetic tunnel junction pattern MTJ can be formed between the bottom electrode BE and the top electrode TE. For example, the magnetic tunnel junction pattern MTJ may include a first magnetic metal pattern 112, a non-magnetic metal oxide pattern 122, and a second magnetic metal pattern 132. The first magnetic metal pattern 112 may be a pinned layer whose magnetization direction is fixed. The non-magnetic metal oxide pattern 122 may be a tunnel barrier layer. The second magnetic metal pattern 132 may be a free layer whose magnetization direction can be changed.

[0055] Figure 17 Examples are shown of a first vertical magnetic field 114 in a first magnetic metal pattern 112 and a second vertical magnetic field 134 in a second magnetic metal pattern 132.

[0056] Reference Figure 17 The first magnetic metal pattern 112 and the second magnetic metal pattern 132 may each have a first vertical magnetic field 114 and a second vertical magnetic field 134. The first vertical magnetic field 114 and the second vertical magnetic field 134 may be substantially orthogonal to the interface orientation between the first magnetic metal pattern 112 or the second magnetic metal pattern 132 and the non-magnetic metal oxide pattern 122. The first vertical magnetic field 114 may be formed in the first magnetic metal pattern 112. The first vertical magnetic field 114 may have a fixed direction independent of external current. The second vertical magnetic field 134 may be formed in the second magnetic metal pattern 132. The second vertical magnetic field 134 can be used for magnetic recording information. The direction of the second vertical magnetic field 134 can be changed based on the direction of the write current between the bottom electrode BE and the top electrode TE. The direction of the second vertical magnetic field 134 can change the read current between the bottom electrode BE and the top electrode TE. When the direction of the second vertical magnetic field 134 points downwards, the read current can increase. When the direction of the second vertical magnetic field 134 points upwards, the read current can decrease. The energy difference of the second vertical magnetic field 134 can be represented or explained by vertical magnetic anisotropy.

[0057] Reference Figure 9 , Figure 11 and Figure 16 When the second magnetic metal layer 130 (or the second magnetic metal pattern 132) is formed to have approximately to approximately When the thickness is such that the first perpendicular magnetic anisotropy G4 can be greater than the second perpendicular magnetic anisotropy G5 and the third perpendicular magnetic anisotropy G6, the first perpendicular magnetic anisotropy G4 can be obtained from a second magnetic metal layer 130 deposited at an extremely low temperature of about 50 K. When the second magnetic metal layer 130 is formed at an extremely low temperature of about 50 K to approximately... When the thickness is sufficient, the maximum perpendicular magnetic anisotropy can be imparted to the second perpendicular magnetic field 134 in the second magnetic metal pattern 132.

[0058] Reference Figure 5 and Figure 12 A thin-layer deposition apparatus (not shown) can form a protective layer 150 (S70) on the top electrode TE and the lower interlayer dielectric layer 102. The protective layer 150 may include one or more of a metal oxide (e.g., TiO2) and a metal nitride (e.g., TiN) formed by a chemical vapor deposition method. The protective layer 150 may be formed conformally.

[0059] Reference Figure 5 and Figure 13 A thin-layer deposition apparatus (not shown) can form an upper interlayer dielectric layer 160 on the protective layer 150 (S80). The upper interlayer dielectric layer 160 may comprise, for example, silicon oxide formed by a chemical vapor deposition method. A chemical mechanical polishing method can planarize the upper interlayer dielectric layer 160 to expose the top surface of the top electrode TE.

[0060] Reference Figure 5 and Figure 14 The thin-layer deposition apparatus, photolithography apparatus, and etching apparatus can form bit lines BL (S90) on the upper interlayer dielectric layer 160 and the top electrode TE. The thin-layer deposition apparatus can form a metal layer on the upper interlayer dielectric layer 160 and the top electrode TE using sputtering or chemical vapor deposition methods. The photolithography apparatus can form a photoresist pattern on the metal layer. The etching apparatus can use the photoresist pattern as an etching mask to partially remove the metal layer to form the bit lines BL.

[0061] As described above, sputtering apparatuses according to some exemplary embodiments of the present invention may use a cooling unit that cools the chuck and the substrate on the chuck to extremely low temperatures to reduce the surface roughness of the magnetic metal layer formed on the substrate and improve the perpendicular magnetic anisotropy.

[0062] Although the inventive concept has been described in conjunction with some exemplary embodiments shown in the accompanying drawings, those skilled in the art will understand that various changes and modifications can be made without departing from the technical spirit and essential features of the inventive concept. Therefore, it will be understood that the above exemplary embodiments are illustrative in all respects and not restrictive.

[0063] This application claims priority to Korean Patent Application No. 10-2019-0113431, filed on September 16, 2019, with the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.

Claims

1. A method for manufacturing a magnetic storage device, the method comprising: A first magnetic metal layer is formed on the substrate; A non-magnetic metal oxide layer is formed on the first magnetic metal layer using a first sputtering process that keeps the substrate at room temperature or above room temperature, the first sputtering process being performed by a first sputtering gun. as well as A second magnetic metal layer is formed on the non-magnetic metal oxide layer using a second sputtering process that cools the substrate to 50K or lower, the second sputtering process being performed by a second sputtering gun. The first sputtering process uses a first inert gas having a first evaporation point to generate a first plasma, and the second sputtering process uses a second inert gas having a second evaporation point lower than the first evaporation point to generate a second plasma with a density greater than the first plasma. The first inert gas is provided in the chamber. The second sputtering gun has a gas supply source connected to the second inert gas and a nozzle orifice that sprays the second inert gas into the chamber to generate the second plasma.

2. The method of claim 1, wherein forming the second magnetic metal layer comprises: Cool the substrate to a temperature equal to or below 50K; as well as The second inert gas is provided on the substrate.

3. The method according to claim 2, wherein the second inert gas comprises neon.

4. The method of claim 1, wherein the second magnetic metal layer is formed having a thickness of 8 Å to 10 Å and a surface roughness of 2 Å or less.

5. The method of claim 1, wherein the first magnetic metal layer is formed using a third sputtering process that cools the substrate to 50K or lower.

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