Semiconductor device and method for manufacturing the same

Abstract

A semiconductor device comprises: a first electrode; a second electrode; and a multilayer stack, which comprises a hafnium oxide layer with a tetragonal crystal structure located between the first electrode and the second electrode, wherein the multilayer stack comprises: a seed layer for promoting tetragonal crystallization of the hafnium oxide layer and having a tetragonal crystal structure; and an enhancement layer for enhancing the dielectric constant of the hafnium oxide layer.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Korean Patent Application No. 10-2019-0144440, filed on November 12, 2019, which is hereby incorporated by reference in its entirety. Technical Field

[0003] Various embodiments of the present invention relate to a semiconductor device, and more particularly, to a semiconductor device and a method of manufacturing the semiconductor device. Background Art

[0004] Recently, as the integration of semiconductor memories has been accelerated, the operating voltage has become lower while the unit cell area has been reduced. This requires high-k materials with high capacitance and low leakage current.

[0005] Zirconia (ZrO2) is a high-k material used as the dielectric layer of capacitors, but there are limits to how much capacitance can be added using zirconia. Therefore, new methods of increasing the capacitance of such devices are needed. Summary of the invention

[0006] Embodiments of the present invention relate to a semiconductor device including a dielectric layer having a high dielectric constant and a low leakage current, and a method of manufacturing the semiconductor device.

[0007] According to an embodiment of the present invention, a semiconductor device includes: a first electrode; a second electrode; a multilayer stack, which is located between the first electrode and the second electrode and includes a hafnium oxide layer with a tetragonal crystal structure, wherein the multilayer stack includes: a seed layer, which is used to promote tetragonal crystallization of the hafnium oxide layer and has a tetragonal crystal structure; and an enhancement layer, which is used to improve the dielectric constant of the hafnium oxide layer.

[0008] According to another embodiment of the present invention, a method for manufacturing a semiconductor device includes: forming a multilayer stack of an enhancement layer, a seed layer having a doping layer embedded therein, and an initial hafnium oxide layer over a first electrode; forming a heat source layer over the multilayer stack to crystallize the initial hafnium oxide layer into tetragonal hafnium oxide; and forming a second electrode over the heat source layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figures 1A to 1C is a cross-sectional view showing a semiconductor device according to an embodiment of the present invention.

[0010] Figure 2A is a cross-sectional view showing a semiconductor device according to another embodiment of the present invention.

[0011] Figure 2B The seed layer is shown in detail.

[0012] Figure 2C A seed layer according to a comparative example is shown.

[0013] Figure 3 It shows that according to Figure 2A A cross-sectional view of a semiconductor device of a modified embodiment.

[0014] FIG. 4A to FIG. 13B are cross-sectional views showing various modified examples of the semiconductor device.

[0015] Fig.14A and Fig. 14B is a cross-sectional view illustrating an example of a method for manufacturing a semiconductor device.

[0016] Fig.15A and Fig. 15B is a cross-sectional view showing another embodiment of a method for manufacturing a semiconductor device.

[0017] Fig.16A and Fig. 16B is a cross-sectional view showing still another embodiment of a method for manufacturing a semiconductor device.

[0018] Fig.17A and Fig. 17B is used to describe the formation FIG. 14A to FIG. 16B A flow chart of an example of a method of forming a seed layer is shown.

[0019] Fig.18A is used to describe the formation FIG. 14A to FIG. 16B A flow chart of an example of a method of forming an initial hafnium oxide layer is shown.

[0020] Fig.18B is used to describe the formation FIG. 14A to FIG. 16B Flow chart of an example of a method of stacking a seed layer and an initial hafnium oxide layer as shown in FIG.

[0021] Fig.19A and Fig.19B is a cross-sectional view illustrating a method for crystallizing initial hafnium oxide according to a comparative example.

[0022] Figures 20A to 20C A storage unit is shown.

[0023] FIG. 21A to FIG. 21F An application example of a capacitor of a memory cell is shown.

[0024] FIG. 22A to FIG. 22D is a cross-sectional view illustrating a method for forming a capacitor according to another embodiment of the present invention. DETAILED DESCRIPTION

[0025] Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. However, the present invention can be implemented in different forms and should not be construed as being limited to the embodiments set forth herein. On the contrary, these embodiments are provided to make the present disclosure clear and complete, and will fully describe the scope of the present invention to those skilled in the art. Throughout the entire disclosure, in each of the drawings and embodiments of the present invention, the same reference numerals refer to the same parts.

[0026] The drawings are not drawn to scale, and in some cases, the scale may have been exaggerated in order to clearly illustrate features of the embodiments. When a first layer is referred to as being "on" a second layer or "on" a substrate, it refers not only to the case where the first layer is directly formed on the second layer or on the substrate, but also to the case where a third layer exists between the first layer and the second layer or substrate.

[0027] Hafnium oxide having a tetragonal crystal structure (hereinafter, simply referred to as "tetragonal hafnium oxide") may have a high energy band gap (hereinafter simply referred to as "high band gap") and a high dielectric constant of about 60 or more. The tetragonal hafnium oxide may have a higher dielectric constant than tetragonal zirconium oxide.

[0028] According to conventional methods, to form tetragonal hafnium oxide, an initial hafnium oxide may be deposited, and then a high temperature crystallization annealing process may be performed at a temperature of about 900° C. or higher. However, the high temperature crystallization annealing process may deteriorate adjacent structures.

[0029] Hereinafter, various embodiments of the present invention provide methods of forming tetragonal hafnium oxide without performing a high temperature crystallization annealing process.

[0030] Since it is difficult to form pure tetragonal hafnium oxide by using a single layer of hafnium oxide, in an embodiment of the present invention, pure tetragonal hafnium oxide may be formed at a low temperature by using a seed layer as a crystallization promoting layer.

[0031] As will be described later, by using at least one of a seed layer, a doping layer, and a heat source layer, tetragonal hafnium oxide may be easily formed at a low temperature of about 500° C. or less.

[0032] In a multilayer stack including a hafnium oxide layer and a zirconium oxide layer, a polarization phenomenon may be caused by contact of the hafnium oxide layer and the zirconium oxide layer, and the polarization phenomenon may provide a high dielectric constant. An enhancement layer KBL may be proposed as a buffer layer for activating polarization of the hafnium oxide layer. The enhancement layer KBL may be disposed under the hafnium oxide layer or the zirconium oxide layer. The enhancement layer KBL may be disposed between the hafnium oxide layer and the zirconium oxide layer.

[0033] Figure 1A is a cross-sectional view showing a semiconductor device 100 according to an embodiment of the present invention.

[0034] Reference Figure 1A , the semiconductor device 100 may include an ultra high k structure (ULKS). The ultra high k structure (ULKS) may include a multilayer stack in which at least two layers are stacked. For example, the ultra high k structure (ULKS) may include a reinforcement layer KBL and a dielectric layer DE. The reinforcement layer KBL may be thinner than the dielectric layer DE.

[0035] The dielectric layer DE may include a single layer material, a multilayer material, a laminated material, a mixed material or a combination thereof. The dielectric layer DE may have a high dielectric constant of about 7 or higher. The dielectric layer DE may include at least one high-k material. A high-k material may refer to a material having a dielectric constant higher than that of silicon oxide. A high-k material may refer to a material having a dielectric constant higher than that of silicon nitride. The dielectric layer DE may include at least one ultra-high-k material. An ultra-high-k material may be made of a material having a dielectric constant higher than that of a high-k material. An ultra-high-k material may have a dielectric constant of about 60 or higher. The dielectric layer DE may include at least one ferroelectric material. The dielectric layer DE may include at least one antiferroelectric material. The dielectric layer DE may include at least one ferroelectric material or an antiferroelectric material.

[0036] The dielectric layer DE may have a hafnium oxide-based structure. For example, the dielectric layer DE may include at least one hafnium oxide layer. The dielectric layer DE may have a multi-layer structure including at least one hafnium oxide layer.

[0037] Reference Figure 1A , the ultra high-k structure ULKS may be or include a stack of a reinforcement layer KBL and a dielectric layer DE. The reinforcement layer KBL and the dielectric layer DE may be in direct contact with each other. The reinforcement layer KBL may be formed below the dielectric layer DE.

[0038] The reinforcement layer KBL may enhance the dielectric constant of the dielectric layer DE. The reinforcement layer KBL may be used as a dielectric constant enhancer (k-booster). The reinforcement layer KBL may enable the dielectric layer DE to have an improved dielectric constant. For example, the dielectric layer DE alone may have a dielectric constant of about 60, but when the dielectric layer DE and the reinforcement layer KBL are in contact with each other, the dielectric layer DE may have a dielectric constant greater than 60. The reinforcement layer KBL may be used as a polarization enhancing layer that strengthens the polarization of the dielectric layer DE, and may improve the dielectric constant of the dielectric layer DE by strengthening the polarization.

[0039] The reinforcement layer KBL may be or include a metal. The metal of the reinforcement layer KBL may be or include a divalent metal, a trivalent metal, or a pentavalent metal. The divalent metal and the trivalent metal may have a high electron affinity.

[0040] The reinforcement layer KBL and the dielectric layer DE may be made of different materials. The dielectric layer DE may be or include a first metal, and the reinforcement layer KBL may be or include a second metal. The first metal and the second metal may be different. The first metal may include at least one of hafnium, zirconium, aluminum, and titanium. The second metal may include at least one of niobium, tantalum, and vanadium. In one embodiment, the dielectric layer DE may include an oxide of the first metal, and the reinforcement layer KBL may include an oxide of the second metal. For example, the dielectric layer DE may include hafnium oxide, zirconium oxide, aluminum oxide, titanium oxide, or a combination thereof, and the reinforcement layer KBL may include niobium oxide, tantalum oxide, or vanadium oxide. According to another embodiment of the present invention, the dielectric layer DE may be an oxide of the first metal, and the reinforcement layer KBL may be an oxynitride of the second metal. For example, the dielectric layer DE may include hafnium oxide, zirconium oxide, aluminum oxide, titanium oxide, or a combination thereof, and the reinforcement layer KBL may include niobium oxynitride, tantalum oxynitride, or vanadium oxynitride. According to an embodiment of the present invention, the dielectric layer DE may include hafnium oxide, and the reinforcement layer KBL may include niobium oxide or niobium oxynitride.

[0041] As described above, the enhancement layer KBL may be or include a second metal and oxygen. In addition, the enhancement layer KBL may be or include a second metal, oxygen and nitrogen. In order to enhance the dielectric constant of the dielectric layer DE, the oxygen content and the nitrogen content of the enhancement layer KBL may be adjusted. For example, when the enhancement layer KBL includes an oxide of the second metal, the oxygen content may be adjusted within a range of approximately 1 to 50 atomic %. When the enhancement layer KBL includes an oxynitride of the second metal, the oxygen content may be greater than the nitrogen content, and the total content of oxygen and nitrogen may be within a range of approximately 60 to 70 atomic %. It is advantageous to enhance the dielectric constant of the dielectric layer DE by adjusting the oxygen content of the enhancement layer KBL. The enhancement layer KBL may include a metal oxynitride having a higher oxygen content than a nitrogen content.

[0042] The reinforcement layer KBL may be thinner than the dielectric layer DE. The reinforcement layer KBL may have a thickness of about to Thickness.

[0043] According to an embodiment of the present invention, the dielectric layer DE may be or include a high-k material having a tetragonal crystal structure. Hereinafter, the high-k material having a tetragonal crystal structure may also be referred to as a tetragonal high-k material. The tetragonal high-k material may have a higher dielectric constant than a non-tetragonal high-k material. The non-tetragonal high-k material may have an amorphous structure or a crystal structure, such as a monoclinic crystal structure.

[0044] The tetragonal high-k material may be or include tetragonal hafnium oxide. The tetragonal hafnium oxide may have a dielectric constant of about 60. Due to the presence of the enhancement layer KBL, the dielectric layer DE may be or include tetragonal hafnium oxide having an increased dielectric constant greater than 60. For example, when the tetragonal hafnium oxide has a dielectric constant of about 60 without the enhancement layer KBL, the dielectric constant of the tetragonal hafnium oxide in a structure in direct contact with the enhancement layer KBL may be increased from about 70 to about 150.

[0045] As described above, since the dielectric layer DE has a tetragonal crystal structure, the dielectric layer DE may have a high dielectric constant, and the dielectric constant may be further enhanced by the reinforcement layer KBL.

[0046] Figure 1B and 1C It shows that according to Figure 1A A cross-sectional view of a semiconductor device according to a modified example of FIG. Figure 1A and Figure 1B is a cross-sectional view showing an example of a single reinforcement layer, Figure 1C is a cross-sectional view showing an example of a double reinforcement layer.

[0047] Reference Figure 1B , the semiconductor device 100A may include an ultra-high-k structure ULKS. The ultra-high-k structure ULKS may be or include a stack of a dielectric layer DE and a reinforcement layer KBL. The reinforcement layer KBL may be formed above the dielectric layer DE. When the reinforcement layer KBL is formed above the dielectric layer DE, the dielectric constant of the dielectric layer DE may be increased.

[0048] Reference Figure 1C , the semiconductor device 100B may include an ultra-high-k structure ULKS. The ultra-high-k structure ULKS may be or include a stack of a first reinforcement layer KBL1, a dielectric layer DE, and a second reinforcement layer KBL2. The first reinforcement layer KBL1 may be formed below the dielectric layer DE, and the second reinforcement layer KBL2 may be formed above the dielectric layer DE. The first reinforcement layer KBL1 and the second reinforcement layer KBL2 may be formed as follows: Figure 1A and Figure 1B The reinforcement layer KBL is formed of the same material as the material thereof.

[0049] The first reinforcement layer KBL1 and the second reinforcement layer KBL2 may be formed of the same material or different materials. For example, both the first reinforcement layer KBL1 and the second reinforcement layer KBL2 may be niobium oxide. The first reinforcement layer KBL1 may be niobium oxide, and the second reinforcement layer KBL2 may include niobium oxynitride, tantalum oxide, tantalum oxynitride, vanadium oxide, or vanadium oxynitride. The first reinforcement layer KBL1 may include niobium oxynitride, and the second reinforcement layer KBL2 may include niobium oxide, tantalum oxide, tantalum oxynitride, vanadium oxide, or vanadium oxynitride. The first reinforcement layer KBL1 may include niobium oxide, tantalum oxide, tantalum oxynitride, vanadium oxide, or vanadium oxynitride, and the second reinforcement layer KBL2 may be niobium oxynitride. The first reinforcement layer KBL1 may include niobium oxynitride, tantalum oxide, tantalum oxynitride, vanadium oxide, or vanadium oxynitride, and the second reinforcement layer KBL2 may be niobium oxynitride.

[0050] According to another embodiment of the present invention, the oxygen contents of the first reinforcement layer KBL1 and the second reinforcement layer KBL2 may be the same or different. The first reinforcement layer KBL1 may have a greater oxygen content than the second reinforcement layer KBL2. The first reinforcement layer KBL1 may have a smaller oxygen content than the second reinforcement layer KBL2.

[0051] As described above, the dielectric constant of the dielectric layer DE can be improved by the first reinforcement layer KBL1 and the second reinforcement layer KBL2. The dielectric constant improvement effect of the double reinforcement layers KBL1 and KBL2 can be greater than the dielectric constant improvement effect of the single reinforcement layer KBL. For example, when the dielectric layer DE includes tetragonal hafnium oxide, the dielectric constant of the tetragonal hafnium oxide with a structure having a double reinforcement layer can be increased from about 70 to about 150.

[0052] Figure 2A is a cross-sectional view showing a semiconductor device according to another embodiment of the present invention.

[0053] Reference Figure 2A , the semiconductor device 110 may be or include a capacitor 111. The capacitor 111 may include a first electrode 101, a multilayer stack DE11, and a second electrode 102. The capacitor 111 may further include a heat source layer 103 disposed between the multilayer stack DE11 and the second electrode 102. The multilayer stack DE11 may include a reinforcement layer KBL. The reinforcement layer KBL may be disposed on a bottom surface of the multilayer stack DE11. The reinforcement layer KBL may be in direct contact with the first electrode 101. The multilayer stack DE11 may correspond to Figure 1A Ultra-high-k structure ULKS.

[0054] The first electrode 101 may be or include a metal-containing material. The first electrode 101 may be or include a metal, a metal nitride, a metal carbide, a conductive metal nitride, a conductive metal oxide, or a combination thereof. The first electrode 101 may be or include titanium (Ti), titanium nitride (TiN), tantalum nitride (TaN), tungsten (W), tungsten nitride (WN), ruthenium (Ru), iridium (Ir), ruthenium oxide (RuO2), iridium oxide (IrO2), niobium nitride (NbN), molybdenum nitride (MoN), or a combination thereof. According to another embodiment of the present invention, the first electrode 101 may be or include a silicon-containing material. The first electrode 101 may be or include silicon, silicon germanium, or a combination thereof. According to another embodiment of the present invention, the first electrode 101 may be or include a stack of a metal-containing material and a silicon-containing material. The first electrode 101 may be referred to as a "bottom electrode or storage node".

[0055] The second electrode 102 may be or include a silicon-containing material, a germanium-containing material, a metal-containing material, or a combination thereof. The second electrode 102 may be or include a metal, a metal nitride, a metal carbide, a conductive metal nitride, a conductive metal oxide, or a combination thereof. The second electrode 102 may be or include titanium (Ti), titanium nitride (TiN), tantalum nitride (TaN), titanium nitride carbide (TiCN), tantalum nitride carbide (TaCN), tungsten (W), tungsten nitride (WN), ruthenium (Ru), iridium (Ir), ruthenium oxide (RuO2), niobium nitride (NbN), molybdenum nitride (MoN), iridium oxide (IrO2), silicon (Si), germanium (Ge), silicon germanium (SiGe), or a combination thereof. The second electrode 102 may be or include a "Si / SiGe stack", in which silicon germanium is stacked on top of silicon. The second electrode 102 may be or include a "Ge / SiGe" stack, in which silicon germanium is stacked on top of germanium. The second electrode 102 may be formed by stacking silicon germanium on top of a metal nitride. For example, the second electrode 102 may be formed by stacking silicon germanium (SiGe) over titanium nitride (TiN). According to another embodiment of the present invention, the second electrode 102 may be formed by stacking titanium nitride (TiN), silicon germanium (SiGe), and tungsten (W) in the order mentioned. According to another embodiment of the present invention, the second electrode 102 may be formed by stacking titanium nitride (TiN), silicon germanium (SiGe), and tungsten nitride (WN) in the order mentioned.

[0056] The multilayer stack DE11 may be or include a stack of a reinforcement layer KBL, an ultra-high-k layer 105, a seed layer 106, and a leakage barrier layer 107 in the order described. At least one of the seed layer 106 and the ultra-high-k layer 105 may be made of a material having a tetragonal crystal structure. In one embodiment, each of the seed layer 106 and the ultra-high-k layer 105 may be made of a material having a tetragonal crystal structure.

[0057] The seed layer 106 may be used as a seed to promote crystallization of the ultra-high-k layer 105 .

[0058] The enhancement layer KBL may enhance the dielectric constant of the ultra-high-k layer 105. The enhancement layer KBL may serve as a dielectric constant enhancer. The ultra-high-k layer 105 may have a dielectric constant increased by the enhancement layer KBL. For example, the ultra-high-k layer 105 may have a dielectric constant of about 150 by the enhancement layer KBL.

[0059] The enhancement layer KBL and the ultra-high-k layer 105 may be different materials. The ultra-high-k layer 105 may be or include a first metal, and the enhancement layer KBL may be or include a second metal. The first metal and the second metal may be different. The ultra-high-k layer 105 may be an oxide of the first metal, and the enhancement layer KBL may be an oxide of the second metal. According to another embodiment of the present invention, the ultra-high-k layer 105 may be an oxide of the first metal, and the enhancement layer KBL may be an oxynitride of the second metal. The ultra-high-k layer 105 may include hafnium oxide, zirconium oxide, aluminum oxide, titanium oxide, or a combination thereof. The enhancement layer KBL may include niobium oxide, niobium oxynitride, tantalum oxide, tantalum oxynitride, vanadium oxide, or vanadium oxynitride. In an embodiment of the present invention, the ultra-high-k layer 105 may be hafnium oxide, and the enhancement layer KBL may be niobium oxide or niobium oxynitride. According to an embodiment of the present invention, the seed layer 106 may be or include tetragonal zirconium oxide, and the ultra-high-k layer 105 may include ultra-high-k hafnium oxide. The ultra-high-k hafnium oxide may be or include tetragonal hafnium oxide. Due at least in part to the enhancement layer KBL, the ultra-high-k hafnium oxide in this structure may have an increased dielectric constant of about 150 or more.

[0060] As described above, the enhancement layer KBL may be or include a second metal and oxygen. The enhancement layer KBL may be or include a second metal, oxygen, and nitrogen. In order to improve the dielectric constant of the ultra-high-k layer 105, the oxygen content and the nitrogen content of the enhancement layer KBL1 may be adjusted. For example, when the enhancement layer KBL includes an oxide of the second metal, the oxygen content may be adjusted in the range of approximately 1 to 50 atomic %. When the enhancement layer KBL includes an oxynitride of the second metal, the nitrogen content may be lower than the oxygen content. The dielectric constant of the ultra-high-k layer 105 may be improved by adjusting the oxygen content of the enhancement layer KBL.

[0061] The reinforcement layer KBL may be thinner than the ultra-high-k layer 105. The reinforcement layer KBL may have a thickness of approximately arrive Thickness.

[0062] The ultra-high-k layer 105 may include a material that is crystallized into a tetragonal crystal structure by a low-temperature heat source. Here, a low-temperature heat source in a temperature range of about 300 to 500° C. may be provided. The low-temperature heat source may be provided while forming the heat source layer 103. The low-temperature heat source does not include a separate high-temperature crystallization annealing process.

[0063] The ultra-high-k layer 105 may be referred to as a "hafnium oxide-based dielectric layer" or simply "hafnium oxide layer 105". In one embodiment, each of the hafnium oxide layer 105 and the seed layer 106 may be made of a material having a tetragonal crystal structure. The leakage barrier layer 107 may reduce leakage current of the multilayer stack DE11.

[0064] The heat source layer 103 may provide a low temperature heat source for crystallization of the hafnium oxide layer 105. The heat source layer 103 may be used as a heat source for crystallizing the hafnium oxide layer 105 into a tetragonal crystal structure. The heat source layer 103 may provide a low temperature heat source of about 300 to 500° C. The heat source layer 103 may have a strong tensile stress. For example, it may have a tensile stress of about 0.5 GPa to 2.0 GPa. The strong tensile stress may promote the tetragonal crystallization of the hafnium oxide layer 105.

[0065] The heat source layer 103 may be a conductive material. The heat source layer 103 may be in direct contact with the second electrode 102. The heat source layer 103 may be a metal-based material. The heat source layer 103 may be or include a metal, a metal nitride, or a metal silicon nitride. The heat source layer 103 may be or include titanium nitride (TiN), titanium silicon nitride (TiSiN), tungsten (W), tungsten nitride (WN), molybdenum nitride (MoN), or niobium nitride (NbN).

[0066] According to the present invention, a high temperature crystallization annealing process commonly used in conventional techniques is not required to obtain tetragonal crystallization of the hafnium oxide layer 105. On the contrary, by using the seed layer 106, when the heat source layer 103 is deposited, the hafnium oxide layer 105 can be crystallized into a tetragonal crystal structure even at a low temperature. For example, the heat source layer 103 can be formed by atomic layer deposition (ALD) and can be deposited at a temperature of about 300 to 500° C. The seed layer 106 can also be crystallized into a tetragonal crystal structure during the deposition of the heat source layer 103. As a result, the hafnium oxide layer 105 and the seed layer 106 can be crystallized into a tetragonal crystal structure by low temperature heat of the heat source layer 103.

[0067] The heat source layer 103 may correspond to a portion of the second electrode 102. For example, when titanium nitride (TiN) and silicon germanium (SiGe) are stacked as the second electrode 102, titanium nitride (TiN) may be used as the heat source layer 103.

[0068] The hafnium oxide layer 105 may directly contact the enhancement layer KBL and the seed layer 106. The hafnium oxide layer 105 may be formed over the enhancement layer KBL, and the seed layer 106 may be formed over the hafnium oxide layer 105. The enhancement layer KBL and the hafnium oxide layer 105 may be in direct contact with each other. The seed layer 106 may be formed between the hafnium oxide layer 105 and the leakage barrier layer 107. The enhancement layer KBL, the hafnium oxide layer 105, the seed layer 106, and the leakage barrier layer 107 may be sequentially deposited by atomic layer deposition (ALD).

[0069] The seed layer 106 may be used as a seed for promoting tetragonal crystallization of the hafnium oxide layer 105 when the heat source layer 103 is formed. The seed layer 106 may help the hafnium oxide layer 105 to crystallize into a tetragonal crystal structure. Since the seed layer 106 has a high dielectric constant of about 40 or more, the capacitance of the capacitor 111 may be increased, and since the hafnium oxide layer 105 has a high dielectric constant of about 150, the capacitance of the capacitor 111 may be further increased. The seed layer 106 may also be used to suppress leakage current of the dielectric layer stack DE11.

[0070] The seed layer 106 may be or include a high-k material having a tetragonal crystal structure. The seed layer 106 may be or include a zirconium oxide-based material. The seed layer 106 may be or include tetragonal zirconium oxide. According to another embodiment of the present invention, the seed layer 106 may be or include a material having a tetragonal crystal structure in addition to tetragonal zirconium oxide. For example, the seed layer 106 may be niobium oxide, germanium oxide, tin oxide, molybdenum oxide, tantalum oxide, or titanium oxide.

[0071] The hafnium oxide layer 105 may have a higher dielectric constant than the seed layer 106. For example, the seed layer 106 may have a dielectric constant of about 40, and the hafnium oxide layer 105 may have a dielectric constant of about 150. As the seed layer 106, tetragonal zirconium oxide may have a dielectric constant of about 40. The capacitor 111 including the hafnium oxide layer 105 and the seed layer 106 may have a high capacitance. The capacitor 111 including the hafnium oxide layer 105 and the seed layer 106 may have a higher capacitance than a capacitor including only the seed layer 106. As a result, the capacitance of the capacitor 111 may be increased by applying the hafnium oxide layer 105 having a higher dielectric constant than the seed layer 106 and having a tetragonal crystal structure.

[0072] The hafnium oxide layer 105 may have a higher band gap than the seed layer 106. Therefore, the dielectric layer stack DE11 including the hafnium oxide layer 105 may be beneficial for suppressing leakage current. The hafnium oxide layer 105 may improve the effective work function (eWF) between the second electrode 102 and the multilayer stack DE11. For example, when titanium nitride (TiN) is applied as the second electrode 102, an effective work function of about 4.7 eV may be obtained by the hafnium oxide layer 105. At the same time, tetragonal zirconium oxide (ZrO2) may obtain an effective work function of about 4.5 eV. Therefore, due to the hafnium oxide layer 105, a higher effective work function than tetragonal zirconium oxide may be obtained, so the leakage current of the multilayer stack DE11 may be suppressed.

[0073] The hafnium oxide layer 105 may be thinner than the seed layer 106. Even if the thickness of the hafnium oxide layer 105 is thin, it may have a high dielectric constant of about 60 or more.

[0074] The hafnium oxide layer 105 and the seed layer 106 may be in direct contact, which is beneficial for crystallizing the hafnium oxide layer 105 into a tetragonal crystal structure.

[0075] The multilayer stack DE11 may include a multilayer structure in which the reinforcement layer KBL is in direct contact with the hafnium oxide layer 105. The multilayer stack DE11 may include at least one direct contact interface.

[0076] The multilayer stack DE11 may include a direct contact interface in which the reinforcement layer KBL1 and the hafnium oxide layer 105 are in direct contact. When the reinforcement layer KBL includes niobium oxide, a stack in which the reinforcement layer KBL1 and the hafnium oxide layer 105 are sequentially stacked may be referred to as an "NH stack". The direct contact interface may be provided in the NH stack. The multilayer stack DE11 may include at least one direct contact interface. For example, the multilayer stack DE11 may include at least one NH stack.

[0077] The hafnium oxide layer 105 may have a pure tetragonal crystal structure. The crystal structure of the hafnium oxide layer 105 may not be a mixture of an amorphous structure, a monoclinic crystal structure, and a tetragonal crystal structure, but may be only a tetragonal crystal structure. The hafnium oxide layer 105 having a pure tetragonal crystal structure may have a higher dielectric constant than a hafnium oxide layer having a mixed crystal structure. The hafnium oxide layer 105 having a pure tetragonal crystal structure may have a higher dielectric constant than a hafnium oxide layer having a monoclinic crystal structure. The dielectric constant of the hafnium oxide layer having a monoclinic crystal structure may be about 40, and the dielectric constant of the hafnium oxide layer having a pure tetragonal crystal structure may be about 60.

[0078] The hafnium oxide layer 105 may further include a dopant that can promote crystallization. Examples of suitable crystallization-promoting dopants may include strontium (Sr), lanthanum (La), gadolinium (Gd), aluminum (Al), silicon (Si), yttrium (Y), zirconium (Zr), niobium (Nb), bismuth (Bi), germanium (Ge), dysprosium (Dy), titanium (Ti), cerium (Ce), magnesium (Mg), nitrogen (N) or a combination thereof. The hafnium oxide layer 105 may be made of a material having a tetragonal crystal structure doped with a dopant. For example, the hafnium oxide layer 105 may be a tetragonal hafnium oxide (HfO2) layer doped with lanthanum (La). The crystallization-promoting dopant may not only promote the crystallization of the hafnium oxide layer 105, but also increase the dielectric constant. The crystallization-promoting dopant may further activate the polarization characteristics of the hafnium oxide layer 105.

[0079] As described above, the hafnium oxide layer 105 may provide an extremely high dielectric constant, a low leakage current, and a high effective work function.

[0080] The dielectric layer stack DE11 may further include a doping layer 104. The doping layer 104 may further promote crystallization of the hafnium oxide layer 105 and further suppress leakage current of the dielectric layer stack DE11.

[0081] The doping layer 104 may be very thinly embedded in the seed layer 106. The doping layer 104 may not separate grains in the seed layer 106 from each other. In other words, the tetragonal crystal structure of the seed layer 106 may not be separated even if the doping layer 104 is embedded. The doping layer 104 may be formed by doping in the seed layer 106.

[0082] When the seed layer 106 includes tetragonal zirconia, the doping layer 104 may be or include tetragonal zirconia doped with a dopant. Examples of dopants for the doping layer 104 may include, for example, aluminum (Al) or beryllium (Be). For example, the doping layer 104 may include aluminum-doped tetragonal zirconia or beryllium-doped tetragonal zirconia.

[0083] The doping layer 104 may adjust the thickness of the hafnium oxide layer 105 and the seed layer 106. Due to the inclusion of the doping layer 104, the hafnium oxide layer 105 having a predetermined thickness or greater may be formed. The doping layer 104 may adjust the thickness of the hafnium oxide layer 105 to be sufficiently crystallized. For example, the thickness of the crystallized hafnium oxide layer 105 may be adjusted to be approximately 20 to 300 nm. The seed layer 106 may be thicker than the hafnium oxide layer 105. Due to the high thickness during deposition, the zirconium oxide used as the seed layer 106 may easily obtain a tetragonal crystal structure. The seed layer 106 may be made of a material having a tetragonal crystal structure at a thickness during deposition, and may further promote the formation of a tetragonal crystal structure through a subsequent low-temperature heat treatment process. The hafnium oxide layer 105 may be formed to be thin enough so that even if it has a non-tetragonal crystal structure during deposition, it may be crystallized into a tetragonal crystal structure through the seed layer 106 and a subsequent low-temperature heat treatment process.

[0084] The doping layer 104 may have a higher energy band gap than each of the seed layer 106 and the hafnium oxide layer 105. The hafnium oxide layer 105 may have an energy band gap (hereinafter referred to as "band gap") of about 6 eV, and the seed layer 106 may have a band gap of about 5.8 eV. The doping layer 104 may have a band gap of about 8.8 eV to 10.6 eV.

[0085] In this way, the crystallization of the hafnium oxide layer 105 can be further promoted by the doping layer 104 , and the high band gap of the doping layer 104 can suppress the leakage current of the capacitor 111 .

[0086] The leakage barrier layer 107 may include a high bandgap material. The leakage barrier layer 107 may include a material having a higher bandgap than the seed layer 106 and the hafnium oxide layer 105. The leakage barrier layer 107, the seed layer 106, and the hafnium oxide layer 105 may be different materials. The leakage barrier layer 107 may be or include a high-k material, but may have a lower dielectric constant than the hafnium oxide layer 105 and the seed layer 106. The leakage barrier layer 107 may have a higher dielectric constant than silicon oxide and silicon nitride. For example, the leakage barrier layer 107 may be or include aluminum oxide or beryllium oxide. The beryllium oxide may be amorphous. The beryllium oxide may have a wurtzite crystal structure or a rock salt structure. The leakage barrier layer 107 may be formed by atomic layer deposition (ALD). The leakage barrier layer 107 may be much thinner than the seed layer 106 and the hafnium oxide layer 105. The leakage barrier layer 107 and the doping layer 104 may have the same thickness. Since the leakage barrier layer 107 has a relatively lower dielectric constant than the seed layer 106 and the hafnium oxide layer 105, the leakage barrier layer 107 and the doping layer 104 may be formed to be very thin to increase the capacitance of the capacitor 111. The leakage barrier layer 107 may be thicker than the doping layer 104.

[0087] According to another embodiment of the present invention, the leakage barrier layer 107 may be formed of the same material as the doping layer 104. For example, the leakage barrier layer 107 may include aluminum-doped zirconium oxide or beryllium-doped zirconium oxide. In this case, the leakage barrier layer 107 may be made of a material having a tetragonal crystal structure.

[0088] Figure 2Bis a detailed view of the seed layer 106 .

[0089] Reference Figure 2B , the seed layer 106 may have a doped layer 104. The doped layer 104 is embedded in the seed layer 106. The seed layer 106 may include grains 106G arranged vertically from the top surface of the hafnium oxide layer 105 in the thickness direction. The doped layer 104 is embedded in the seed layer 106 to provide vertical continuity of the grains 106G. The seed layer 106 may have vertical continuity of the grains 106G. The seed layer 106 with the doped layer 104 may be defined as an undoped seed lower layer 106L, a doped layer 104, and an undoped seed upper layer 106U. Each undoped seed lower layer 106L, the doped layer 104, and the undoped seed upper layer 106U may be made of a material having a tetragonal crystal structure. The grains 106G of the undoped seed lower layer 106L, the doped layer 104, and the undoped seed upper layer 106U may be continuous and not separated. The doping layer 104 may not separate the grains 106G of the undoped seed crystal lower layer 106L and the grains 106G of the undoped seed crystal upper layer 106U from each other. The undoped seed crystal upper layer 106U may be thicker than the undoped seed crystal lower layer 106L (T2>T1). The doping layer 104 may be much thinner than the undoped seed crystal upper layer 106U and the undoped seed crystal lower layer 106L. The doping layer 104 may be disposed between the undoped seed crystal lower layer 106L and the undoped seed crystal upper layer 106U, and at the same time have an extremely thin thickness that does not separate the grains of the undoped seed crystal lower layer 106L from the grains of the undoped seed crystal upper layer 106U from each other. The doping layer 104 has a thickness that achieves vertical continuity from the grains 106G of the undoped seed crystal lower layer 106L to the grains 106G of the undoped seed crystal upper layer 106U.

[0090] For example, each of the undoped seed crystal lower layer 106L and the undoped seed crystal upper layer 106U may be undoped tetragonal zirconia. The doped layer 104 may be tetragonal zirconia doped with a dopant. In addition, as an example, the doped layer 104 may include aluminum or beryllium as a dopant. In one embodiment, the grains 106G may be grains of tetragonal zirconia.

[0091] As described above, although the doping layer 104 includes a dopant, the doping layer 104 may not be an oxide layer of the dopant. For example, the doping layer 104 may not be an aluminum oxide region, but may be an aluminum-doped tetragonal zirconium oxide region. Furthermore, the doping layer 104 may not be a beryllium oxide region, but may be a beryllium-doped tetragonal zirconium oxide region.

[0092] The undoped seed crystal lower layer 106L, the doped layer 104, and the undoped seed crystal upper layer 106U may be referred to as a first zirconium oxide region, an aluminum-doped zirconium oxide region, and a second zirconium oxide region, respectively. The seed crystal layer 106 with the doped layer 104 may include a "Z-AZ-Z stack" in which the first zirconium oxide region, the aluminum-doped zirconium oxide region, and the second zirconium oxide region are stacked in the stated order.

[0093] According to another embodiment of the present invention, the doping layer 104 may be or include an aluminum oxide region having a discontinuous extremely thin thickness. Here, the discontinuous extremely thin thickness may be a thickness that does not separate the grains of the undoped seed crystal lower layer 106L from the grains of the undoped seed crystal upper layer 106U.

[0094] Figure 2C A seed layer 106 ′ according to a comparative example is shown.

[0095] Reference Figure 2C , an aluminum oxide layer (Al2O3) 104' may be formed between the undoped seed crystal lower layer 106L and the undoped seed crystal upper layer 106U. The aluminum oxide layer (Al2O3) 104' may have a continuous thickness, so that the aluminum oxide layer 104' may separate the grains 106G of the undoped seed crystal lower layer 106L from the grains 106G of the undoped seed crystal upper layer 106U (see reference numeral 106S). The grains 106G of the seed crystal layer 106' are vertically separated by the aluminum oxide layer 104'. The aluminum oxide layer (Al2O3) 104' may be thicker than the doped layer 104 and may be a continuous layer. The seed crystal layer 106' may be referred to as a "ZAZ stack".

[0096] As described above, when the grains 106G of the seed layer 106' are separated by the aluminum oxide layer 104', the dielectric constant of the seed layer 106' decreases. When the dielectric constant of the seed layer 106' decreases, the equivalent oxide layer thickness T ox Will not decrease.

[0097] As described above, the hafnium oxide layer 105 can be crystallized into a tetragonal crystal structure through the heat source layer 103 and the seed layer 106 having the doping layer 104. Moreover, even at a low temperature, the hafnium oxide layer 105 can be crystallized into a tetragonal crystal structure through the seed layer 106. In addition, due to the hafnium oxide layer 105 and the seed layer 106 having the doping layer 104, the equivalent oxide layer thickness T can be reduced. ox , while increasing the dielectric constant of the dielectric layer stack DE11. The doping layer 104 and the leakage blocking layer 107 can suppress the leakage current of the multilayer stack DE11. In addition, the enhancement layer KBL1 can further enhance the higher dielectric constant of the hafnium oxide layer 105.

[0098] As described above, the seed layer 106 may promote crystallization of the hafnium oxide layer 105 into a tetragonal crystal structure, and the enhancement layer KBL may improve polarization of the hafnium oxide layer 105. As a result, the hafnium oxide layer 105 may have a dielectric constant increased by promoting a tetragonal crystal structure, and the increased dielectric constant may be promoted by polarization enhancement.

[0099] When the multilayer stack DE11 includes a first stack (which is a stack of the hafnium oxide layer 105 and the seed layer 106), wherein the first stack includes the seed layer 106 but does not include the reinforcement layer KBL, the oxide layer 105 may have a dielectric constant of about 60 due to its tetragonal crystal structure. When the multilayer stack DE11 includes a second stack (which is a stack of the reinforcement layer KBL, the hafnium oxide layer 105 and the seed layer 106), wherein the second stack includes all of the reinforcement layer KBL and the seed layer 106, the hafnium oxide layer 105 may have a dielectric constant of about 150.

[0100] The hafnium oxide layer 105 may have a dielectric constant adjusted by a dipole changed by an electric field applied from the outside. The enhancement layer KBL may increase the dielectric constant of the hafnium oxide layer 105.

[0101] Figure 3 It shows that according to Figure 2A A cross-sectional view of a semiconductor device of a modified embodiment.

[0102] Reference Figure 3 , capacitor 111' can be similar to Figure 2A The capacitor 111′ may include a first electrode 101, a second electrode 102, and a multilayer stack DE11′ between the first electrode 101 and the second electrode 102. The capacitor 111′ may further include a heat source layer 103 disposed between the multilayer stack DE11′ and the second electrode 102.

[0103] The multilayer stack DE11' may be or include a stack of an enhancement layer KBL, a hafnium oxide layer 105, a seed layer 106 having a doping layer 104, a leakage barrier layer 107, and an interface control layer 108. Each seed layer 106 and the hafnium oxide layer 105 may be made of a material having a tetragonal crystal structure. The seed layer 106 may be or include tetragonal zirconium oxide. The hafnium oxide layer 105 may include ultra-high-k hafnium oxide, but the ultra-high-k hafnium oxide may be made of a material having a tetragonal crystal structure. The seed layer 106 may be used as a seed for promoting the crystallization of the hafnium oxide layer 105, and the enhancement layer KBL may improve the dielectric constant of the hafnium oxide layer 105.

[0104] When forming the second electrode 102 and the heat source layer 103, the interface control layer 108 may protect the hafnium oxide layer 105 and the seed layer 106. In addition, the interface control layer 108 may reduce leakage current of the multilayer stack DE11'.

[0105] The interface control layer 108 may be made of a material that is reduced before the hafnium oxide layer 105 and the seed layer 106 when depositing the heat source layer 103 and the second electrode 102. The interface control layer 108 may serve as a leakage current block having a large effective work function (eWF) and a large conduction band offset (CBO). Moreover, the interface control layer 108 may not increase the equivalent oxide layer thickness T of the multilayer stack DE11′. ox .

[0106] The interface control layer 108 may be made of a material having a high electronegativity. The interface control layer 108 may have a higher Pauling electronegativity than the hafnium oxide layer 105. The material used for the interface control layer 108 may include a material having a higher Pauling electronegativity (hereinafter referred to as "electronegativity") than each of the hafnium oxide layer 105 and the seed layer 106. When the electronegativity is high, the material is difficult to be oxidized, but is easily reduced. Therefore, oxygen in the interface control layer 108 but not in the hafnium oxide layer 105 and the seed layer 106 may be removed. As a result, the interface control layer 108 can prevent oxygen loss in the hafnium oxide layer 105 and the seed layer 106.

[0107] The interface control layer 108 may include atoms with high electronegativity, such as metal atoms, silicon atoms, or germanium atoms. The interface control layer 108 may be or include titanium (Ti), tantalum (Ta), aluminum (Al), tin (Sn), molybdenum (Mo), ruthenium (Ru), iridium (Ir), niobium (Nb), germanium (Ge), silicon (Si), nickel (Ni), or a combination thereof. The interface control layer 108 may be or include a stack of molybdenum and molybdenum nitride (Mo / MoN) or a stack of tungsten and tungsten nitride (W / WN). The interface control layer 108 may include a conductive material. The conductive material for the interface control layer 108 may include atoms with high electronegativity, such as metal atoms, silicon atoms, or germanium atoms. The interface control layer 108 serves as a portion of the second electrode 102.

[0108] The interface control layer 108 may be or include titanium oxide, tantalum oxide, niobium oxide, aluminum oxide, silicon oxide (SiO 2 ), tin oxide, germanium oxide, molybdenum dioxide, molybdenum trioxide, iridium oxide, ruthenium oxide, nickel oxide, or a combination thereof.

[0109] The leakage blocking layer 107 and the interface control layer 108 may be disposed at a higher level than the hafnium oxide layer 105 and the seed layer 106 .

[0110] FIG. 4A to FIG. 13B1 is a cross-sectional view showing various modified embodiments of semiconductor devices. Hereinafter, in an embodiment of the present invention, semiconductor devices 112A to 120B may be capacitors. Multilayer stacks DE12 to DE39 may include at least one hafnium oxide layer, at least one enhancement layer, and at least one seed layer. The multilayer stack may include at least one direct contact interface, and the direct contact interface may include a hafnium oxide layer and an enhancement layer in direct contact. The enhancement layer may be disposed below the hafnium oxide layer.

[0111] Reference Figure 4A , the semiconductor device 112A may be similar to Figure 2A The semiconductor device 112A may include a first electrode 101, a second electrode 102, and a multilayer stack DE12 disposed between the first electrode 101 and the second electrode 102. The semiconductor device 112A may further include a heat source layer 103 disposed between the multilayer stack DE12 and the second electrode 102.

[0112] The multilayer stack DE12 may include a first reinforcement layer KBL1, a first hafnium oxide layer 105A, a seed layer 106, a second reinforcement layer KBL2, a second hafnium oxide layer 105B, and a leakage barrier layer 107 stacked one on top of another in the following order. The first reinforcement layer KBL1 may be formed between the first electrode 101 and the first hafnium oxide layer 105A, and the seed layer 106 may be the first hafnium oxide layer 105A and the second hafnium oxide layer. The second reinforcement layer KBL2 may be formed between the seed layer 106 and the second hafnium oxide layer 105B. The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 105A, and the second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 105B.

[0113] The first hafnium oxide layer 105A may directly contact the first reinforcement layer KBL1 and the seed layer 106, and the second hafnium oxide layer 105B may directly contact the second reinforcement layer KBL2 and the leakage barrier layer 107. The first hafnium oxide layer 105A and the seed layer 106 may directly contact each other, and the seed layer 106 and the second hafnium oxide layer 105B may directly contact each other.

[0114] The first hafnium oxide layer 105A may be thicker than the second hafnium oxide layer 105B. Therefore, the occupation space of the first hafnium oxide layer 105A in the multi-layer stack DE12 may be larger than the occupation space of the second hafnium oxide layer 105B.

[0115] The first hafnium oxide layer 105A and the second hafnium oxide layer 105B may have a pure tetragonal crystal structure. The first hafnium oxide layer 105A and the second hafnium oxide layer 105B may have the same dielectric constant. The first hafnium oxide layer 105A and the second hafnium oxide layer 105B may have a higher dielectric constant than the seed layer 106.

[0116] According to another embodiment of the present invention, the first hafnium oxide layer 105A may have a pure tetragonal crystal structure, and the second hafnium oxide layer 105B may have a mixed crystal structure including a tetragonal crystal structure and a monoclinic crystal structure. The first hafnium oxide layer 105A may have a higher dielectric constant than the second hafnium oxide layer 105B. In this way, even if the second hafnium oxide layer 105B has a lower dielectric constant than the first hafnium oxide layer 105A, the second hafnium oxide layer 105B may have a higher dielectric constant than the seed layer 106. The seed layer 106 may promote the tetragonal crystallization of the second hafnium oxide layer 105B. Although the second hafnium oxide layer 105B is a mixed tetragonal crystal structure and a monoclinic crystal structure, the second hafnium oxide layer 105B may have a dominant tetragonal crystal structure through the seed layer 106. Since the first hafnium oxide layer 105A is thicker than the second hafnium oxide layer 105A, the dielectric layer stack DE12 may have a predominantly tetragonal crystal structure.

[0117] The multilayer stack DE12 may further include a doping layer 104. The doping layer 104 may be very thinly embedded in the seed layer 106. The doping layer 104 may further promote the crystallization of the first and second hafnium oxide layers 105A and 105B, and further suppress the leakage current of the multilayer stack DE12. The doping layer 104 may have a higher band gap than the seed layer 106, the first hafnium oxide layer 105A, and the second hafnium oxide layer 105B. The first and second hafnium oxide layers 105A and 105B may have a band gap of about 6 eV, and the seed layer 106 may have a band gap of about 5.8 eV. The doping layer 104 may have a band gap of about 8.8 eV to 10.6 eV.

[0118] The multilayer stack DE12 may include at least one direct contact interface. For example, the multilayer stack DE12 may include a direct contact interface between the first reinforcement layer KBL1 and the first hafnium oxide layer 105A, and a direct contact interface between the second reinforcement layer KBL2 and the second hafnium oxide layer 105B.

[0119] In addition, the multilayer stack DE12 may further include a direct contact interface between the first hafnium oxide layer 105A and the seed layer 106 and a direct contact interface between the seed layer 106 and the second hafnium oxide layer 105B. When the seed layer 106 includes tetragonal zirconium oxide, the stack of the first hafnium oxide layer 105A and the seed layer 106 may be referred to as a "HZ stack", and the stack of the seed layer 106 and the second hafnium oxide layer 105B may be referred to as a "ZH stack".

[0120] The seed layer 106 may promote crystallization of the first and second hafnium oxide layers 105A and 105B. The dielectric constant of the first hafnium oxide layer 105A may be increased by the first enhancement layer KBL1. The dielectric constant of the second hafnium oxide layer 105B may be increased by the second enhancement layer KBL2.

[0121] Reference Figure 4B , the semiconductor device 112B may be similar to Figure 4A Therefore, the same reference numerals may refer to the same elements, and any further discussion regarding the same elements will not be repeated.

[0122] The semiconductor device 112B may include a first electrode 101, a multilayer stack DE13, a heat source layer 103, and a second electrode 102. The multilayer stack DE13 may include a first reinforcement layer KBL1, a first hafnium oxide layer 105A, a seed layer 106 having a doping layer 104, a second reinforcement layer KBL2, and a second hafnium oxide layer 105B, a leakage barrier layer 107, and an interface control layer 108 stacked one on top of another in the following order.

[0123] The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 105A, and the second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 105B. The first hafnium oxide layer 105A may directly contact the first reinforcement layer KBL1, and the second hafnium oxide layer 105B may directly contact the second reinforcement layer KBL2. The first reinforcement layer KBL1 may be disposed between the first electrode 101 and the first hafnium oxide layer 105A. The second reinforcement layer KBL2 may be disposed between the seed layer 106 and the second hafnium oxide layer 105B.

[0124] The seed layer 106 may promote crystallization of the first and second hafnium oxide layers 105A and 105B. The dielectric constant of the first hafnium oxide layer 105A may be increased by the first enhancement layer KBL1. The dielectric constant of the second hafnium oxide layer 105B may be increased by the second enhancement layer KBL2.

[0125] Reference Figure 4C , the semiconductor device 112C may be similar to Figure 4A Therefore, the same reference numerals may refer to the same elements, and any further discussion about the same elements will not be repeated. The semiconductor device 112C may include a first electrode 101, a multilayer stack DE14, a heat source layer 103, and a second electrode 102.

[0126] The multilayer stack DE14 may include a first enhancement layer KBL1, a first hafnium oxide layer 105A, a first seed layer 106A having a doping layer 104, a second enhancement layer KBL2, a second hafnium oxide layer 105B, a second seed layer 106B, and a leakage barrier layer 107 stacked one on top of another in the following order. The first enhancement layer KBL1 may be formed under the first hafnium oxide layer 105A, and the second enhancement layer KBL2 may be formed under the second hafnium oxide layer 105B. The first hafnium oxide layer 105A may directly contact the first enhancement layer KBL1, and the second hafnium oxide layer 105B may directly contact the second enhancement layer KBL2. The first enhancement layer KBL1 may be disposed between the first electrode 101 and the first hafnium oxide layer 105A. The second enhancement layer KBL2 may be disposed between the first seed layer 106A and the second hafnium oxide layer 105B.

[0127] The first seed layer 106A and the second seed layer 106B may be the same material. The first seed layer 106A and the second seed layer 106B may be made of a material having a tetragonal crystal structure. The first seed layer 106A and the second seed layer 106B may be or include tetragonal zirconia. The first seed layer 106A may be tetragonal zirconia with a doped layer 104, and the second seed layer 106B may include undoped tetragonal zirconia. Here, the doped layer 104 may not be present in the undoped tetragonal zirconia. The first seed layer 106A may be thicker than the second seed layer 106B, so the first seed layer 106A may occupy a larger space in the dielectric layer stack DE14.

[0128] As described above, the doping layer 104 may be embedded in the first seed layer 106A, while no doping layer is formed in the second seed layer 106B. The first seed layer 105A and the second seed layer 106B may further promote crystallization of the second hafnium oxide layer 105B.

[0129] According to another embodiment of the present invention, the leakage barrier layer 107 may be embedded in the second seed layer 106B.

[0130] Crystallization of the first and second hafnium oxide layers 105A and 105B may be promoted by the first seed layer 106A and the second seed layer 106B. The dielectric constant of the first hafnium oxide layer 105A may be increased by the first enhancement layer KBL1. The dielectric constant of the second hafnium oxide layer 105B may be increased by the second enhancement layer KBL2.

[0131] Reference Figure 4D , the semiconductor device 112D may be similar to Figure 4CTherefore, the same reference numerals may refer to the same elements, and any further discussion about the same elements will not be repeated. The semiconductor device 112D may include a first electrode 101, a multilayer stack DE15, a heat source layer 103, and a second electrode 102.

[0132] The multilayer stack DE15 may include a first reinforcement layer KBL1, a first hafnium oxide layer 105A, a first seed layer 106A having a doping layer 104, a second reinforcement layer KBL2, a second hafnium oxide layer 105B, a second seed layer 106B, a leakage barrier layer 107, and an interface control layer 108 stacked one on top of another in the following order.

[0133] The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 105A, and the second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 105B. The first hafnium oxide layer 105A may directly contact the first reinforcement layer KBL1, and the second hafnium oxide layer 105B may directly contact the second reinforcement layer KBL2.

[0134] Crystallization of the first and second hafnium oxide layers 105A and 105B may be promoted by the first seed layer 106A and the second seed layer 106B. The dielectric constant of the first hafnium oxide layer 105A may be increased by the first enhancement layer KBL1. The dielectric constant of the second hafnium oxide layer 105B may be increased by the second enhancement layer KBL2.

[0135] Reference Figure 4C and Figure 4D , the first seed layer 106A, the second seed layer 106B and the heat source layer 103 can promote the tetragonal crystallization of the first hafnium oxide layer 105A and the second hafnium oxide layer 105B. The heat source layer 103 can provide a low temperature heat treatment process in which the first hafnium oxide layer 105A and the second hafnium oxide layer 105B can be crystallized into a tetragonal crystal structure. The first hafnium oxide layer 105A and the second hafnium oxide layer 105B can be crystallized into a tetragonal crystal structure through the first seed layer 106A. The second hafnium oxide layer 105B can be crystallized into a tetragonal crystal structure through the second seed layer 106B. The second hafnium oxide layer 105B can be crystallized into a tetragonal crystal structure through the first seed layer 106A and the second seed layer 106B.

[0136] Both the first hafnium oxide layer 105A and the second hafnium oxide layer 105B may have a pure tetragonal crystal structure.

[0137] According to another embodiment of the present invention, the first hafnium oxide layer 105A may have a pure tetragonal crystal structure, and the second hafnium oxide layer 105B may be made of a material having a tetragonal crystal structure and a monoclinic crystal structure mixed together. The first hafnium oxide layer 105A may have a higher dielectric constant than the second hafnium oxide layer 105B. As described above, even if the second hafnium oxide layer 105B has a lower dielectric constant than the first hafnium oxide layer 105A, the second hafnium oxide layer 105B may also have a higher dielectric constant than the first and second seed crystal layers 106A and 106B. Although the second hafnium oxide layer 105B includes a tetragonal crystal structure and a monoclinic crystal structure mixed together, the tetragonal crystal structure may be more dominant than the monoclinic crystal structure in the second hafnium oxide layer 105B. Since the first hafnium oxide layer 105A is thicker than the second hafnium oxide layer 105B, the tetragonal crystal structure may be dominant in the multilayer stacks DE14 and DE15.

[0138] Reference FIG. 4A to FIG. 4D , each of the first hafnium oxide layer 105A and the second hafnium oxide layer 105B may further include a dopant for promoting crystallization. Here, the dopant may be a material that is the same as or different from the dopant of the doping layer 104. The dopant may include strontium (Sr), lanthanum (La), gadolinium (Gd), aluminum (Al), silicon (Si), yttrium (Y), zirconium (Zr), niobium (Nb), bismuth (Bi), germanium (Ge), dysprosium (Dy), titanium (Ti), cerium (Ce), magnesium (Mg) or nitrogen (N). The first and second hafnium oxide layers 105A and 105B may be made of a material having a tetragonal crystal structure doped with a dopant.

[0139] Reference Figure 5A , the semiconductor device 113A may include a first electrode 101 , a multilayer stack DE16 , a heat source layer 103 , and a second electrode 102 .

[0140] The multilayer stack DE16 may include a first reinforcement layer KBL1, a first hafnium oxide layer 115A, a first seed layer 116A, a second reinforcement layer KBL2, a second hafnium oxide layer 115B, a second seed layer 116B having a doping layer 104, a third reinforcement layer KBL3, a third hafnium oxide layer 115C and a leakage blocking layer 107 stacked one on top of another in the following order.

[0141] The crystallization of the first to third hafnium oxide layers 115A, 115B, and 115C may be promoted by the first seed layer 116A and the second seed layer 116B. The dielectric constant of the first hafnium oxide layer 115A may be improved by the first reinforcement layer KBL1. The dielectric constant of the second hafnium oxide layer 115B may be improved by the second reinforcement layer KBL2. The dielectric constant of the third hafnium oxide layer 115C may be improved by the third reinforcement layer KBL3.

[0142] The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 115A, the second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 115B, and the third reinforcement layer KBL3 may be formed under the third hafnium oxide layer 115C. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 115A, the second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 115B, and the third reinforcement layer KBL3 may directly contact the third hafnium oxide layer 115C.

[0143] The doping layer 104 may not be embedded in the first seed layer 116A. The doping layer 104 may be embedded in the second seed layer 116B. The first seed layer 116A may be thinner than the second seed layer 116B.

[0144] The first hafnium oxide layer 115A may be thicker than the second hafnium oxide layer 115B and the third hafnium oxide layer 115C. According to another embodiment of the present invention, the first hafnium oxide layer 115A, the second hafnium oxide layer 115B and the third hafnium oxide layer 115C may have the same thickness.

[0145] Reference Figure 5B , the semiconductor device 113B may be similar to Figure 5A Therefore, the same reference numerals may refer to the same elements, and any further discussion regarding the same elements will not be repeated.

[0146] The semiconductor device 113B may include a first electrode 101, a multilayer stack DE17, a heat source layer 103, and a second electrode 102. The multilayer stack DE17 may include a first reinforcement layer KBL1, a first hafnium oxide layer 115A, a first seed layer 116A, a second reinforcement layer KBL2, a second hafnium oxide layer 115B, a second seed layer 116B having a doping layer 104, a third reinforcement layer KBL3, a third hafnium oxide layer 115C, and a leakage barrier layer 107 stacked one on top of another in the following order. The multilayer stack DE17 may further include an interface control layer 108 between the leakage barrier layer 107 and the heat source layer 103.

[0147] The crystallization of the first to third hafnium oxide layers 115A, 115B, and 115C may be promoted by the first seed layer 116A and the second seed layer 116B. The dielectric constant of the first hafnium oxide layer 115A may be improved by the first reinforcement layer KBL1. The dielectric constant of the second hafnium oxide layer 115B may be improved by the second reinforcement layer KBL2. The dielectric constant of the third hafnium oxide layer 115C may be improved by the third reinforcement layer KBL3.

[0148] The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 115A, the second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 115B, and the third reinforcement layer KBL3 may be formed under the third hafnium oxide layer 115C. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 115A, the second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 115B, and the third reinforcement layer KBL3 may directly contact the third hafnium oxide layer 115C.

[0149] Reference Figure 5A and Figure 5B , the first seed layer 116A, the second seed layer 116B and the heat source layer 103 can promote the tetragonal crystallization of the first hafnium oxide layer 115A, the second hafnium oxide layer 115B and the third hafnium oxide layer 115C. The heat source layer 103 can provide a low temperature heat treatment process in which the first hafnium oxide layer 115A, the second hafnium oxide layer 115B and the third hafnium oxide layer 115C can be crystallized into a tetragonal crystal structure. The first hafnium oxide layer 115A and the second hafnium oxide layer 115B can be crystallized into a tetragonal crystal structure through the first seed layer 116A. The second hafnium oxide layer 115B and the third hafnium oxide layer 115C can be crystallized into a tetragonal crystal structure through the second seed layer 116B.

[0150] The first hafnium oxide layer 115A, the second hafnium oxide layer 115B, and the third hafnium oxide layer 115C may all have a pure tetragonal crystal structure. According to another embodiment of the present invention, the first hafnium oxide layer 115A and the second hafnium oxide layer 115B may have a pure tetragonal crystal structure, and the third hafnium oxide layer 115C may have a monoclinic crystal structure and a tetragonal crystal structure mixed together. The tetragonal crystal structure may dominate in the third hafnium oxide layer 115C.

[0151] Reference Figure 5C , the semiconductor device 113C may be similar to Figure 5A Therefore, the same reference numerals may refer to the same elements, and any further discussion regarding the same elements will not be repeated.

[0152] The semiconductor device 113C may include a first electrode 101, a multilayer stack DE18, a heat source layer 103, and a second electrode 102. The multilayer stack DE18 may include a first reinforcement layer KBL1, a first hafnium oxide layer 115A, a first seed layer 116A, a second reinforcement layer KBL2, a second hafnium oxide layer 115B, a second seed layer 116B having a doping layer 104, a third reinforcement layer KBL3, a third hafnium oxide layer 115C, a third seed layer 116C, and a leakage blocking layer 107 stacked one on top of another in the following order.

[0153] The third seed layer 116C may be disposed between the third hafnium oxide layer 115C and the leakage barrier layer 107. The first seed layer 116A, the second seed layer 116B, and the third seed layer 116C may be the same material. The first seed layer 116A, the second seed layer 116B, and the third seed layer 116C may be made of a material having a tetragonal crystal structure. The first seed layer 116A, the second seed layer 116B, and the third seed layer 116C may be or include tetragonal zirconia. The second seed layer 116B may be tetragonal zirconia with a doped layer 104, while the first seed layer 116A and the third seed layer 116C may include undoped tetragonal zirconia. Here, the doped layer 104 may not be present in the undoped tetragonal zirconia.

[0154] As described above, the doping layer 104 may be embedded in the second seed layer 116B. The doping layer 104 may not be embedded in the first seed layer 116A and the third seed layer 116C. The third seed layer 116C and the second seed layer 116B may further promote crystallization of the third hafnium oxide layer 115C.

[0155] According to another embodiment of the present invention, the leakage barrier layer 107 may be embedded in the third seed layer 116C. For example, the top region of the seed layer 116C may include the leakage barrier layer 107. The third seed layer 116C may include zirconium oxide, and the leakage barrier layer 107 may include aluminum-doped zirconium oxide.

[0156] The crystallization of the first to third hafnium oxide layers 115A, 115B, and 115C may be promoted by the first to third seed layers 116A to 116C. The dielectric constant of the first hafnium oxide layer 115A may be improved by the first reinforcement layer KBL1. The dielectric constant of the second hafnium oxide layer 115B may be improved by the second reinforcement layer KBL2. The dielectric constant of the third hafnium oxide layer 115C may be improved by the third reinforcement layer KBL3.

[0157] The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 115A, the second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 115B, and the third reinforcement layer KBL3 may be formed under the third hafnium oxide layer 115C. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 115A, the second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 115B, and the third reinforcement layer KBL3 may directly contact the third hafnium oxide layer 115C.

[0158] Reference Figure 5D , the semiconductor device 113D may be similar to Figure 5C Therefore, the same reference numerals may refer to the same elements, and any further discussion regarding the same elements will not be repeated.

[0159] The semiconductor device 113D may include a first electrode 101, a multilayer stack DE19, a heat source layer 103, and a second electrode 102. The multilayer stack DE19 may include a first reinforcement layer KBL1, a first hafnium oxide layer 115A, a first seed layer 116A, a second reinforcement layer KBL2, a second hafnium oxide layer 115B, a second seed layer 116B having a doping layer 104, a third reinforcement layer KBL3, a third hafnium oxide layer 115C, a third seed layer 116C, and a leakage barrier layer 107 stacked one on top of another in the following order. The multilayer stack DE19 may further include an interface control layer 108 between the leakage barrier layer 107 and the heat source layer 103.

[0160] The crystallization of the first to third hafnium oxide layers 115A, 115B, and 115C may be promoted by the first to third seed layers 116A to 116C. The dielectric constant of the first hafnium oxide layer 115A may be improved by the first reinforcement layer KBL1. The dielectric constant of the second hafnium oxide layer 115B may be improved by the second reinforcement layer KBL2. The dielectric constant of the third hafnium oxide layer 115C may be improved by the third reinforcement layer KBL3.

[0161] The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 115A, the second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 115B, and the third reinforcement layer KBL3 may be formed under the third hafnium oxide layer 115C. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 115A, the second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 115B, and the third reinforcement layer KBL3 may directly contact the third hafnium oxide layer 115C.

[0162] Reference FIG. 5A to FIG. 5D , each of the first to third hafnium oxide layers 115A, 115B, and 115C may further include a dopant. The dopant may include strontium (Sr), lanthanum (La), gadolinium (Gd), aluminum (Al), silicon (Si), yttrium (Y), zirconium (Zr), niobium (Nb), bismuth (Bi), germanium (Ge), dysprosium (Dy), titanium (Ti), cerium (Ce), magnesium (Mg), or nitrogen (N). Each of the first to third hafnium oxide layers 115A, 115B, and 115C may be made of a material having a tetragonal crystal structure doped with a dopant.

[0163] Reference Fig. 6A , the semiconductor device 114A may include a first electrode 101 , a multilayer stack DE20 , a heat source layer 103 , and a second electrode 102 .

[0164] The multilayer stack DE20 may include a first seed layer 116A, a first reinforcement layer KBL1, a first hafnium oxide layer 115A, a second seed layer 116B having a doping layer 104, a second reinforcement layer KBL2, a second hafnium oxide layer 115B, and a leakage blocking layer 107 stacked one on another in the following order.

[0165] The first seed layer 116A and the second seed layer 116B may be the same material. The first seed layer 116A and the second seed layer 116B may be made of a material having a tetragonal crystal structure separately. The first seed layer 116A and the second seed layer 116B may be or include tetragonal zirconia. The first seed layer 116A may include undoped tetragonal zirconia, and the second seed layer 116B may include tetragonal zirconia having a doped layer 104. Here, the doped layer 104 may not be present in the undoped tetragonal zirconia.

[0166] As described above, the doping layer 104 may be embedded in the second seed layer 116B. The doping layer 104 may not be embedded in the first seed layer 116A. The second seed layer 116B may promote crystallization of the second hafnium oxide layer 115B. The first seed layer 116A and the second seed layer 116B may further promote crystallization of the first hafnium oxide layer 115A.

[0167] Crystallization of the first and second hafnium oxide layers 115A and 115B may be promoted by the first seed layer 116A and the second seed layer 116B. The dielectric constant of the first hafnium oxide layer 115A may be increased by the first enhancement layer KBL1. The dielectric constant of the second hafnium oxide layer 115B may be increased by the second enhancement layer KBL2.

[0168] The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 115A, and the second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 115B. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 115A, and the second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 115B.

[0169] Reference Figure 6B , the semiconductor device 114B may include a first electrode 101 , a multilayer stack DE21 , a heat source layer 103 , and a second electrode 102 .

[0170] The multilayer stack DE21 may include a first seed layer 116A, a first enhancement layer KBL1, a first hafnium oxide layer 115A, a second seed layer 116B having a doping layer 104, a second enhancement layer KBL2, a second hafnium oxide layer 115B, a third seed layer 116C, and a leakage blocking layer 107 stacked one on top of another in the following order.

[0171] The first seed layer 116A, the second seed layer 116B, and the third seed layer 116C may be the same material. The first to third seed layers 116A, 116B, and 116C may have a tetragonal crystal structure.

[0172] The first to third seed layers 116A, 116B, and 116C may be or include tetragonal zirconia. The second seed layer 116B may be or include tetragonal zirconia with the doping layer 104, and the first seed layer 116A and the third seed layer 116C may include undoped tetragonal zirconia. Here, the doping layer 104 may not exist in the undoped tetragonal zirconia.

[0173] As described above, the doping layer 104 may be embedded in the second seed layer 116B. The doping layer 104 may not be embedded in the first and third seed layers 116A and 116C. The first and second seed layers 116A and 116B may further promote the crystallization of the first hafnium oxide layer 115A. The second and third seed layers 116B and 116C may further promote the crystallization of the second hafnium oxide layer 115B. In another embodiment, the leakage barrier layer 107 may be embedded in the third seed layer 116C.

[0174] As described above, the doping layer 104 may be embedded in the second seed layer 116B. The doping layer 104 may not be embedded in the first and third seed layers 116A and 116C. The first and second seed layers 116A and 116B may further promote the crystallization of the first hafnium oxide layer 115A. The second and third seed layers 116B and 116C may further promote the crystallization of the second hafnium oxide layer 115B.

[0175] According to another embodiment of the present invention, the leakage barrier layer 107 may be embedded in the third seed layer 116C.

[0176] Crystallization of the first and second hafnium oxide layers 115A and 115B may be promoted by the first to third seed layers 116A to 116C. The dielectric constant of the first hafnium oxide layer 115A may be increased by the first enhancement layer KBL1. The dielectric constant of the second hafnium oxide layer 115B may be increased by the second enhancement layer KBL2.

[0177] The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 115A, and the second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 115B. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 115A, and the second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 115B.

[0178] Fig. 6A and Figure 6BThe multilayer stacks DE20 and DE21 may further include an interface control layer (not shown) between the leakage barrier layer 107 and the heat source layer 103. Here, the interface control layer may correspond to the interface control layer 108 of the above-described embodiment of the present invention.

[0179] Reference Fig. 6A and 6B , each of the first and second hafnium oxide layers 115A and 115B may further include a dopant. The dopant may include strontium (Sr), lanthanum (La), gadolinium (Gd), aluminum (Al), silicon (Si), yttrium (Y), zirconium (Zr), niobium (Nb), bismuth (Bi), germanium (Ge), dysprosium (Dy), titanium (Ti), cerium (Ce), magnesium (Mg), or nitrogen (N). Each of the first and second hafnium oxide layers 115A and 115B may be made of a material having a tetragonal crystal structure doped with a dopant.

[0180] Reference Fig. 7A , the semiconductor device 115 may include a first electrode 101, a multilayer stack DE22, a heat source layer 103, and a second electrode 102. Regarding the description of the first electrode 101, the leakage barrier layer 107, the heat source layer 103, and the second electrode 102, reference will be made to the above-mentioned embodiments.

[0181] The multilayer stack DE22 may include a seed layer 206, a reinforcement layer (KBL), a hafnium oxide layer 205, and a doping layer 204. The reinforcement layer KBL may be formed between the seed layer 206 and the hafnium oxide layer 205. The seed layer 206 may directly contact the first electrode 101 and the reinforcement layer KBL, and may be formed between the reinforcement layer KBL and the first electrode 101.

[0182] The enhancement layer KBL may be in direct contact with the hafnium oxide layer 205 , which is beneficial to improving the dielectric constant of the hafnium oxide layer 205 .

[0183] The hafnium oxide layer 205 may have a pure tetragonal crystal structure.

[0184] The multilayer stack DE22 may further include a doping layer 204. The doping layer 204 may further promote the crystallization of the hafnium oxide layer 205 and further suppress the leakage current of the multilayer stack DE22. The doping layer 204 may be very thinly embedded in the hafnium oxide layer 205. The doping layer 204 may not separate the grains of the hafnium oxide layer 205. The tetragonal crystal structure of the hafnium oxide layer 205 may not be separated. The doping layer 204 may be formed by doping the inside of the hafnium oxide layer 205 with a dopant. The doping layer 204 may be embedded in the hafnium oxide layer 205 to be spaced apart from the enhancement layer KBL.

[0185] When the hafnium oxide layer 205 includes tetragonal hafnium oxide, the doping layer 204 may be or include tetragonal hafnium oxide doped with a dopant. Examples of the dopant of the doping layer 204 may include, for example, aluminum (Al) or beryllium (Be). For example, the doping layer 204 may be or include aluminum-doped tetragonal hafnium oxide or beryllium-doped tetragonal hafnium oxide.

[0186] The hafnium oxide layer 205 may be crystallized into a tetragonal crystal structure through the seed layer 206 and the heat source layer 103 .

[0187] The doping layer 204 may have a higher band gap than the seed layer 206 and the hafnium oxide layer 205 .

[0188] In this way, the doping layer 204 can further promote the crystallization of the hafnium oxide layer 205 , while the high band gap of the doping layer 204 can suppress the leakage current of the semiconductor device 115 .

[0189] The leakage blocking layer 107 may be formed between the hafnium oxide layer 205 and the heat source layer 103. For example, the leakage blocking layer 107 may be or include aluminum oxide or beryllium oxide.

[0190] According to another embodiment of the present invention, the leakage blocking layer 107 may be embedded on the top surface of the hafnium oxide layer 205. For example, the leakage blocking layer 107 may include aluminum-doped hafnium oxide or beryllium-doped hafnium oxide.

[0191] Figure 7B is a detailed view of the hafnium oxide layer 205 .

[0192] Reference Figure 7B, in the hafnium oxide layer 205 in which the doping layer 204 is embedded, the doping layer 204 may be embedded in the hafnium oxide layer 205. The hafnium oxide layer 205 having the doping layer 204 may be defined as an undoped hafnium oxide lower layer 205L, a doping layer 204, and an undoped hafnium oxide upper layer 205U. Each of the undoped hafnium oxide lower layer 205L, the doping layer 204, and the undoped hafnium oxide upper layer 205U may be made of a material having a tetragonal crystal structure. The undoped hafnium oxide lower layer 205L, the doping layer 204, and the undoped hafnium oxide upper layer 205U may be continuous and may not separate the grains 205G. The doping layer 204 may not separate the grains 205G of the undoped hafnium oxide lower layer 205L and the grains 205G of the undoped hafnium oxide upper layer 205U from each other. The undoped hafnium oxide lower layer 205L may be thicker than the undoped hafnium oxide upper layer 205U (T21>T22). The doped layer 204 may be much thinner than the undoped hafnium oxide upper layer 205U and the undoped hafnium oxide lower layer 205L. The doped layer 204 may be disposed between the undoped hafnium oxide lower layer 205L and the undoped hafnium oxide upper layer 205U, wherein the doped layer 204 may have an extremely thin thickness that does not separate the grains of the undoped hafnium oxide lower layer 205L from the grains of the undoped hafnium oxide upper layer 205U. The undoped hafnium oxide lower layer 205L and the undoped hafnium oxide upper layer 205U may have the same thickness. The undoped hafnium oxide lower layer 205L may be thinner than the undoped hafnium oxide upper layer 205U.

[0193] In one embodiment, the doping layer 204 may include an aluminum oxide layer having a discontinuous extremely thin thickness so that the doping layer 204 does not separate the grains of the undoped hafnium oxide lower layer 205L from the grains of the undoped hafnium oxide upper layer 205U.

[0194] Each of the undoped hafnium oxide lower layer 205L and the undoped hafnium oxide upper layer 205U may be undoped tetragonal hafnium oxide. The doping layer 204 may be tetragonal hafnium oxide doped with a dopant. For example, the doping layer 204 may include aluminum or beryllium as a dopant.

[0195] In addition, as described above, the doping layer 204 may include a dopant, but the doping layer 204 may not be an oxide layer of the dopant. For example, the doping layer 204 may not be an aluminum oxide (Al2O3) layer, but may be aluminum-doped tetragonal hafnium oxide. In addition, the doping layer 204 may not be a beryllium oxide layer, but may be beryllium-doped tetragonal hafnium oxide.

[0196] The undoped hafnium oxide lower layer 205L, the doped layer 204, and the undoped hafnium oxide upper layer 205U may be referred to as a first hafnium oxide layer, an aluminum-doped hafnium oxide layer, and a second hafnium oxide layer, respectively. The hafnium oxide layer 205 with the doped layer 204 may include a "H-AH-H stack", in which the first hafnium oxide layer, the aluminum-doped hafnium oxide layer, and the second hafnium oxide layer are stacked in the stated order.

[0197] Reference Fig. 8A , the semiconductor device 115A may include a first electrode 101, a multilayer stack DE23, a heat source layer 103, and a second electrode 102. For the first electrode 101, the leakage barrier layer 107, the heat source layer 103, and the second electrode 102, reference may be made to the above-described embodiments.

[0198] The multilayer stack DE23 may include a first seed layer 206A, a enhancement layer (KBL), a hafnium oxide layer 205 , a doping layer 204 , and a second seed layer 206B.

[0199] The first seed layer 206A and the second seed layer 206B facilitate crystallization of the hafnium oxide layer 205 into a tetragonal crystal structure.

[0200] The hafnium oxide layer 205 may have a pure tetragonal crystal structure.

[0201] The multilayer stack DE23 may further include a doping layer 204. The doping layer 204 may further promote the crystallization of the hafnium oxide layer 205. The doping layer 204 may be embedded very thinly in the hafnium oxide layer 205, so that the doping layer 204 may not separate the grains of the hafnium oxide layer 205. The tetragonal crystal structure of the hafnium oxide layer 205 may not be separated. The doping layer 204 may be formed by doping the inside of the hafnium oxide layer 205 with a dopant.

[0202] When the hafnium oxide layer 205 includes tetragonal hafnium oxide, the doping layer 204 may be or include tetragonal hafnium oxide doped with a dopant. The dopant of the doping layer 204 may include, for example, aluminum (Al) or beryllium (Be). For example, the doping layer 204 may be or include aluminum-doped tetragonal hafnium oxide or beryllium-doped tetragonal hafnium oxide.

[0203] The hafnium oxide layer 205 may be crystallized into a tetragonal crystal structure through the first and second seed layers 206A and 206B and the heat source layer 103 .

[0204] The doping layer 204 may have a higher band gap than the first and second seed layers 206A and 206B and the hafnium oxide layer 205 .

[0205] In this manner, the doping layer 204 can further promote the crystallization of the hafnium oxide layer 205 , while the high band gap of the doping layer 204 can suppress the leakage current of the semiconductor device 115A.

[0206] The leakage barrier layer 107 may be formed between the second seed layer 206B and the heat source layer 103. For example, the leakage barrier layer 107 may be or include aluminum oxide or beryllium oxide.

[0207] According to another embodiment of the present invention, the leakage barrier layer 107 may be embedded on the top surface of the second seed layer 206B. The leakage barrier layer 107 may include aluminum-doped zirconium oxide or beryllium-doped zirconium oxide.

[0208] The first and second seed layers 206A and 206B may promote crystallization of the hafnium oxide layer 205. The dielectric constant of the hafnium oxide layer 205 may be improved by the enhancement layer KBL. The enhancement layer KBL may be formed below the hafnium oxide layer 205. The enhancement layer KBL may directly contact the hafnium oxide layer 205.

[0209] Reference Figure 8B , the semiconductor device 115B may be similar to Fig. 8A Therefore, the same reference numerals may refer to the same elements, and any further discussion regarding the same elements will not be repeated.

[0210] The semiconductor device 115B may include a first electrode 101, a multilayer stack DE24, a heat source layer 103, and a second electrode 102. The multilayer stack DE24 may be or include a stack of a first seed layer 206A, a reinforcement layer KBL, a hafnium oxide layer 205 having a doping layer 204, a second seed layer 206B, a leakage barrier layer 107, and an interface control layer 108.

[0211] The first and second seed layers 206A and 206B may promote crystallization of the hafnium oxide layer 205. The dielectric constant of the hafnium oxide layer 205 may be improved by the enhancement layer KBL. The enhancement layer KBL may be formed below the hafnium oxide layer 205. The enhancement layer KBL may directly contact the hafnium oxide layer 205.

[0212] Reference Figure 8C , the semiconductor device 115C may be similar to Fig. 8A Therefore, the same reference numerals may refer to the same elements, and any further discussion regarding the same elements will not be repeated.

[0213] The semiconductor device 115C may include a first electrode 101, a multilayer stack DE25, a heat source layer 103, and a second electrode 102. The multilayer stack DE25 may be or include a stack of a first seed layer 206A, a reinforcement layer KBL, a first hafnium oxide layer 205A having a doping layer 204, a second seed layer 206B, a second reinforcement layer KBL2, a second hafnium oxide layer 205B, and a leakage barrier layer 107 in the following order.

[0214] The first hafnium oxide layer 205A and the second hafnium oxide layer 205B may be the same material. The first hafnium oxide layer 205A and the second hafnium oxide layer 205B may be made of a material having a tetragonal crystal structure. The first hafnium oxide layer 205A and the second hafnium oxide layer 205B may be or include tetragonal hafnium oxide. The first hafnium oxide layer 205A may be or include tetragonal hafnium oxide having a doping layer 204, and the second hafnium oxide layer 205B may include undoped tetragonal hafnium oxide. The undoped tetragonal hafnium oxide does not include the doping layer 204.

[0215] As described above, the doping layer 204 may be embedded in the first hafnium oxide layer 205A. The doping layer 204 may not be embedded in the second hafnium oxide layer 205B. The capacitance of the dielectric layer stack DE25 may be further increased by the second hafnium oxide layer 205B.

[0216] The crystallization of the first and second hafnium oxide layers 205A and 205B may be promoted by the first and second seed layers 206A and 206B. The dielectric constant of the first hafnium oxide layer 205A may be improved by the first enhancement layer KBL1. The dielectric constant of the second hafnium oxide layer 205B may be improved by the second enhancement layer KBL2. The first enhancement layer KBL1 may be formed under the first hafnium oxide layer 205A. The second enhancement layer KBL2 may be formed under the second hafnium oxide layer 205B. The first enhancement layer KBL1 may directly contact the first hafnium oxide layer 205A. The second enhancement layer KBL2 may directly contact the second hafnium oxide layer 205B.

[0217] Reference Fig.8D , the semiconductor device 115D may be similar to Figure 8C Therefore, the same reference numerals may refer to the same elements, and any further discussion regarding the same elements will not be repeated.

[0218] The semiconductor device 115D may include a first electrode 101, a multilayer stack DE26, a heat source layer 103, and a second electrode 102. The multilayer stack DE26 may be or include a stack of a first seed layer 206A, a first enhancement layer KBL1, a first hafnium oxide layer 205A having a doping layer 204, a second seed layer 206B, a second enhancement layer KBL2, a second hafnium oxide layer 205B, a leakage barrier layer 107, and an interface control layer 108.

[0219] The crystallization of the first and second hafnium oxide layers 205A and 205B may be promoted by the first and second seed layers 206A and 206B. The dielectric constant of the first hafnium oxide layer 205A may be improved by the first enhancement layer KBL1. The dielectric constant of the second hafnium oxide layer 205B may be improved by the second enhancement layer KBL2. The first enhancement layer KBL1 may be formed under the first hafnium oxide layer 205A. The second enhancement layer KBL2 may be formed under the second hafnium oxide layer 205B. The first enhancement layer KBL1 may directly contact the first hafnium oxide layer 205A. The second enhancement layer KBL2 may directly contact the second hafnium oxide layer 205B.

[0220] Reference Fig.9A , the semiconductor device 116A may include a first electrode 101 , a multilayer stack DE27 , a heat source layer 103 , and a second electrode 102 .

[0221] The multilayer stack DE27 may be or include a stack of a first seed layer 216A, a first reinforcement layer KBL1, a first hafnium oxide layer 215A, a second seed layer 216B, a second reinforcement layer KBL2, a second hafnium oxide layer 215B having a doping layer 204, a third seed layer 216C, and a leakage barrier layer 107 in the following order.

[0222] The first hafnium oxide layer 215A may include undoped tetragonal hafnium oxide. The first hafnium oxide layer 215A may be thinner than the second hafnium oxide layer 215B.

[0223] The crystallization of the first and second hafnium oxide layers 215A and 215B may be promoted by the first to third seed layers 216A, 216B, and 216C. The dielectric constant of the first hafnium oxide layer 215A may be improved by the first reinforcement layer KBL1. The dielectric constant of the second hafnium oxide layer 215B may be improved by the second reinforcement layer KBL2. The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 215A. The second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 215B. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 215A. The second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 215B.

[0224] Reference Fig. 9B , the semiconductor device 116B may be similar to Fig.9A Therefore, the same reference numerals may refer to the same elements, and any further discussion regarding the same elements will not be repeated.

[0225] The semiconductor device 116B may include a first electrode 101, a multilayer stack DE28, a heat source layer 103, and a second electrode 102. The multilayer stack DE28 may be or include a stack of a first seed layer 216A, a first reinforcement layer KBL1, a first hafnium oxide layer 215A, a second seed layer 216B, a second reinforcement layer KBL2, a second hafnium oxide layer 215B having a doping layer 204, a third seed layer 216C, a leakage barrier layer 107, and an interface control layer 108.

[0226] The crystallization of the first and second hafnium oxide layers 215A and 215B may be promoted by the first to third seed layers 216A, 216B, and 216C. The dielectric constant of the first hafnium oxide layer 215A may be improved by the first reinforcement layer KBL1. The dielectric constant of the second hafnium oxide layer 215B may be improved by the second reinforcement layer KBL2. The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 215A. The second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 215B. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 215A. The second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 215B.

[0227] Reference Fig. 9C , the semiconductor device 116C may be similar to Fig.9A Therefore, the same reference numerals may refer to the same elements, and any further discussion regarding the same elements will not be repeated.

[0228] The semiconductor device 116C may include a first electrode 101, a multilayer stack DE29, a heat source layer 103, and a second electrode 102. The multilayer stack DE29 may be or include a stack of a first seed layer 216A, a first reinforcement layer KBL1, a first hafnium oxide layer 215A, a second seed layer 216B, a second reinforcement layer KBL2, a second hafnium oxide layer 215B having a doping layer 204, a third seed layer 216C, a third reinforcement layer KBL3, a third hafnium oxide layer 215C, and a leakage barrier layer 107 in the following order.

[0229] The first hafnium oxide layer 215A, the second hafnium oxide layer 215B, and the third hafnium oxide layer 215C may be the same material. The first hafnium oxide layer 215A, the second hafnium oxide layer 215B, and the third hafnium oxide layer 215C may be made of a material having a tetragonal crystal structure. The first hafnium oxide layer 215A, the second hafnium oxide layer 215B, and the third hafnium oxide layer 215C may be or include tetragonal hafnium oxide. The first and third hafnium oxide layers 215A and 215C may include undoped tetragonal hafnium oxide. The undoped tetragonal hafnium oxide does not include the doping layer 204.

[0230] As described above, the doping layer 204 may be embedded in the second hafnium oxide layer 215B. The doping layer 204 may not be embedded in the first hafnium oxide layer 215A and the third hafnium oxide layer 215C. The third hafnium oxide layer 215C may further increase the capacitance of the multilayer stack DE29.

[0231] The crystallization of the first to third hafnium oxide layers 215A, 215B, and 215C may be promoted by the first to third seed layers 216A, 216B, and 216C. The dielectric constant of the first hafnium oxide layer 215A may be improved by the first reinforcement layer KBL1. The dielectric constant of the second hafnium oxide layer 215B may be improved by the second reinforcement layer KBL2. The dielectric constant of the third hafnium oxide layer 215C may be improved by the third reinforcement layer KBL3. The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 215A. The second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 215B. The third reinforcement layer KBL3 may be formed under the third hafnium oxide layer 215C. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 215A. The second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 215B. The third reinforcement layer KBL3 may directly contact the third hafnium oxide layer 215C.

[0232] Reference Fig.9D , the semiconductor device 116D may be similar to Fig. 9C Therefore, the same reference numerals may refer to the same elements, and any further discussion regarding the same elements will not be repeated.

[0233] The semiconductor device 116D may include a first electrode 101, a multilayer stack DE30, a heat source layer 103, and a second electrode 102. The multilayer stack DE30 may be or include a stack of a first seed layer 216A, a first reinforcement layer KBL1, a first hafnium oxide layer 215A, a second seed layer 216B, a second reinforcement layer KBL2, a second hafnium oxide layer 215B having a doping layer 204, a third seed layer 216C, a third reinforcement layer KBL3, a third hafnium oxide layer 215C, a leakage barrier layer 107, and an interface control layer 108.

[0234] The crystallization of the first to third hafnium oxide layers 215A, 215B, and 215C may be promoted by the first to third seed layers 216A, 216B, and 216C. The dielectric constant of the first hafnium oxide layer 215A may be improved by the first reinforcement layer KBL1. The dielectric constant of the second hafnium oxide layer 215B may be improved by the second reinforcement layer KBL2. The dielectric constant of the third hafnium oxide layer 215C may be improved by the third reinforcement layer KBL3. The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 215A. The second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 215B. The third reinforcement layer KBL3 may be formed under the third hafnium oxide layer 215C. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 215A. The second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 215B. The third reinforcement layer KBL3 may directly contact the third hafnium oxide layer 215C.

[0235] Reference Fig. 10A , the semiconductor device 117A may include a first electrode 101, a multilayer stack DE31, a heat source layer 103, and a second electrode 102. The multilayer stack DE31 may be or include a stack of a first reinforcement layer KBL1, a first hafnium oxide layer 225A, a first seed layer 226A, a second reinforcement layer KBL2, a hafnium oxide layer 225B having a doping layer 204, a second seed layer 226B, and a leakage barrier layer 107 in the following order.

[0236] The first hafnium oxide layer 225A and the second hafnium oxide layer 225B may be the same material. The first hafnium oxide layer 225A and the second hafnium oxide layer 225B may be made of a material having a tetragonal crystal structure. The first hafnium oxide layer 225A and the second hafnium oxide layer 225B may be or include tetragonal hafnium oxide. The first hafnium oxide layer 225A may include undoped tetragonal hafnium oxide. The undoped tetragonal hafnium oxide does not include the doping layer 204.

[0237] The doping layer 204 may be embedded in the second hafnium oxide layer 225B. The doping layer 204 may not be embedded in the first hafnium oxide layer 225 A. The second hafnium oxide layer 225B may be thicker than the first hafnium oxide layer 225A.

[0238] The crystallization of the first and second hafnium oxide layers 225A and 225B may be promoted by the first and second seed layers 226A and 226B. The dielectric constant of the first hafnium oxide layer 225A may be improved by the first enhancement layer KBL1. The dielectric constant of the second hafnium oxide layer 225B may be improved by the second enhancement layer KBL2. The first enhancement layer KBL1 may be formed under the first hafnium oxide layer 225A. The second enhancement layer KBL2 may be formed under the second hafnium oxide layer 225B. The first enhancement layer KBL1 may directly contact the first hafnium oxide layer 225A. The second enhancement layer KBL2 may directly contact the second hafnium oxide layer 225B.

[0239] Reference Fig. 10B , the semiconductor device 117B may be similar to Fig. 10A Therefore, the same reference numerals may refer to the same elements, and any further discussion regarding the same elements will not be repeated.

[0240] The semiconductor device 117B may include a first electrode 101, a multilayer stack DE32, a heat source layer 103, and a second electrode 102. The multilayer stack DE32 may be or include a stack of a first reinforcement layer KBL1, a first hafnium oxide layer 225A, a first seed layer 226A, a second reinforcement layer KBL2, a second hafnium oxide layer 225B having a doping layer 204, a second seed layer 226B, a third reinforcement layer KBL3, a third hafnium oxide layer 225C, and a leakage barrier layer 107 in the following order.

[0241] The first hafnium oxide layer 225A, the second hafnium oxide layer 225B, and the third hafnium oxide layer 225C may be the same material. The first hafnium oxide layer 225A, the second hafnium oxide layer 225B, and the third hafnium oxide layer 225C may be made of a material having a tetragonal crystal structure. The first hafnium oxide layer 225A, the second hafnium oxide layer 225B, and the third hafnium oxide layer 225C may be or include tetragonal hafnium oxide. The first and third hafnium oxide layers 225A and 225C may include undoped tetragonal hafnium oxide. The undoped tetragonal hafnium oxide does not include the doping layer 204.

[0242] The doping layer 204 may be embedded in the second hafnium oxide layer 225B. The doping layer 204 may not be embedded in the first hafnium oxide layer 225A and the third hafnium oxide layer 225C.

[0243] The crystallization of the first to third hafnium oxide layers 225A, 225B, and 225C may be promoted by the first and second seed layers 226A and 226B. The dielectric constant of the first hafnium oxide layer 225A may be improved by the first reinforcement layer KBL1. The dielectric constant of the second hafnium oxide layer 225B may be improved by the second reinforcement layer KBL2. The dielectric constant of the third hafnium oxide layer 225C may be improved by the third reinforcement layer KBL3. The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 225A. The second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 225B. The third reinforcement layer KBL3 may be formed under the third hafnium oxide layer 225C. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 225A. The second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 225B. The third reinforcement layer KBL3 may directly contact the third hafnium oxide layer 225C.

[0244] Reference Fig. 10A and Fig. 10B An interface control layer (not shown) may be further formed between the leakage blocking layer 107 and the heat source layer 103. With regard to the interface control layer, reference may be made to the above-mentioned embodiments.

[0245] Reference Fig.11A , the semiconductor device 118A may include a first electrode 101 , a multilayer stack DE33 , a heat source layer 103 , and a second electrode 102 .

[0246] The multilayer stack DE33 may be or include a stack of a first seed layer 236A, a first reinforcement layer KBL1, a first hafnium oxide layer 235A, a doping layer 234, a second seed layer 236B, a second reinforcement layer KBL2, a second hafnium oxide layer 235B, and a leakage barrier layer 107 in the following order. When the first seed layer 236A and the second seed layer 236B include tetragonal zirconium oxide, the first reinforcement layer KBL1 may be disposed between the first seed layer 236A and the first hafnium oxide layer 235A. The second reinforcement layer KBL2 may be formed between the second seed layer 236B and the second hafnium oxide layer 235B.

[0247] The doping layer 234 may be disposed between the first hafnium oxide layer 235A and the second seed layer 236B. The doping layer 234 may not separate the grains of the first hafnium oxide layer 235A from the grains of the second seed layer 236B. The first hafnium oxide layer 235A and the second seed layer 236B may have the same thickness. The doping layer 234 may be much thinner than the first hafnium oxide layer 235A and the second seed layer 236B so that it does not separate the grains of the first hafnium oxide layer 235A from the grains of the second seed layer 236B.

[0248] The doping layer 234 may be embedded in the second seed layer 236B. In other words, it may be embedded in the bottom surface of the second seed layer 236B in contact with the first hafnium oxide layer 235A. The doping layer 234 may be, for example, aluminum-doped tetragonal zirconium oxide or beryllium-doped tetragonal zirconium oxide.

[0249] According to another embodiment of the present invention, the doping layer 234 may be embedded on the top surface of the first hafnium oxide layer 235A. The doping layer 234 may be, for example, aluminum-doped tetragonal hafnium oxide or beryllium-doped tetragonal hafnium oxide. The doping layer 234 may be embedded in the first hafnium oxide layer 235A by contacting the direct contact interface of the first hafnium oxide layer 235A and the second seed layer 236B.

[0250] The crystallization of the first and second hafnium oxide layers 235A and 235B may be promoted by the first and second seed layers 236A and 236B. The dielectric constant of the first hafnium oxide layer 235A may be improved by the first reinforcement layer KBL1. The dielectric constant of the second hafnium oxide layer 235B may be improved by the second reinforcement layer KBL2. The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 235A. The second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 235B. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 235A. The second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 235B.

[0251] Reference Fig. 11B , the semiconductor device 118A′ may include a first electrode 101 , a multilayer stack DE33 ′, a heat source layer 103 , and a second electrode 102 .

[0252] The multilayer stack DE33' may be or include a stack of a first seed layer 236A, a first reinforcement layer KBL1, a first hafnium oxide layer 235A, a doping layer 234, a second seed layer 236B, a second reinforcement layer KBL2, a second hafnium oxide layer 235B, a third seed layer 236C, and a leakage barrier layer 107 in the following order. When the first seed layer 236A and the second seed layer 236B include tetragonal zirconia, the first reinforcement layer KBL1 may be disposed between the first seed layer 236A and the first hafnium oxide layer 235A. The second reinforcement layer KBL2 may be formed between the second seed layer 236B and the second hafnium oxide layer 235B. The third seed layer 236C may be formed between the second hafnium oxide layer 235B and the leakage barrier layer 107, and the third seed layer 236C may be or include tetragonal zirconia.

[0253] The doping layer 234 may be disposed between the first hafnium oxide layer 235A and the second seed layer 236B. The doping layer 234 may not separate the grains of the first hafnium oxide layer 235A from the grains of the second seed layer 236B. The first hafnium oxide layer 235A and the second seed layer 236B may have the same thickness. The doping layer 234 may be much thinner than the first hafnium oxide layer 235A and the second seed layer 236B so that it does not separate the grains of the first hafnium oxide layer 235A from the grains of the second seed layer 236B.

[0254] The doping layer 234 may be embedded in the second seed layer 236B. In other words, it may be embedded in the bottom surface of the second seed layer 236B in contact with the first hafnium oxide layer 235A. The doping layer 234 may be, for example, aluminum-doped tetragonal zirconium oxide or beryllium-doped tetragonal zirconium oxide.

[0255] According to another embodiment of the present invention, the doping layer 234 may be embedded on the top surface of the first hafnium oxide layer 235A. Therefore, the doping layer 234 may be, for example, aluminum-doped tetragonal hafnium oxide or beryllium-doped tetragonal hafnium oxide.

[0256] The crystallization of the first and second hafnium oxide layers 235A and 235B may be promoted by the first and second seed layers 236A and 236B. The dielectric constant of the first hafnium oxide layer 235A may be improved by the first reinforcement layer KBL1. The dielectric constant of the second hafnium oxide layer 235B may be improved by the second reinforcement layer KBL2. The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 235A. The second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 235B. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 235A. The second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 235B.

[0257] Reference Fig. 11C , the semiconductor device 118B may include a first electrode 101 , a multilayer stack DE34 , a heat source layer 103 , and a second electrode 102 .

[0258] The multilayer stack DE34 may be or include a stack of a first reinforcement layer KBL1, a first hafnium oxide layer 245A, a first seed layer 246A, a second reinforcement layer KBL2, a second hafnium oxide layer 245B, a doping layer 234, a second seed layer 246B, a third reinforcement layer KBL3, a third hafnium oxide layer 245C and a leakage barrier layer 107 in the following order.

[0259] The doping layer 234 may be disposed between the second hafnium oxide layer 245B and the second seed layer 246B. The doping layer 234 may not separate the grains of the second hafnium oxide layer 245B and the grains of the second seed layer 246B.

[0260] The doping layer 234 may be embedded in the second seed layer 246B. In other words, it may be embedded in the bottom surface of the second seed layer 246B in contact with the second hafnium oxide layer 245B. Therefore, the doping layer 234 may be, for example, aluminum-doped tetragonal zirconium oxide or beryllium-doped tetragonal zirconium oxide.

[0261] According to another embodiment of the present invention, the doping layer 234 may be embedded on the top surface of the second hafnium oxide layer 245B. Therefore, the doping layer 234 may be, for example, aluminum-doped tetragonal hafnium oxide or beryllium-doped tetragonal hafnium oxide.

[0262] The crystallization of the first to third hafnium oxide layers 245A, 245B, and 245C may be promoted by the first and second seed layers 246A and 246B. The dielectric constant of the first hafnium oxide layer 245A may be improved by the first reinforcement layer KBL1. The dielectric constant of the second hafnium oxide layer 245B may be improved by the second reinforcement layer KBL2. The dielectric constant of the third hafnium oxide layer 245C may be improved by the third reinforcement layer KBL3. The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 245A. The second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 245B. The third reinforcement layer KBL3 may be formed under the third hafnium oxide layer 245C. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 245A. The second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 245B. The third reinforcement layer KBL3 may directly contact the third hafnium oxide layer 245C.

[0263] Reference Fig.11D , the semiconductor device 118C may include a first electrode 101 , a multilayer stack DE35 , a heat source layer 103 , and a second electrode 102 .

[0264] The multilayer stack DE35 can be or include a stack of a first reinforcement layer KBL1, a first hafnium oxide layer 245A, a first seed layer 246A, a second reinforcement layer KBL2, a second hafnium oxide layer 245B, a doping layer 234, a second seed layer 246B, a third reinforcement layer KBL3, a third hafnium oxide layer 245C, a third seed layer 246C and a leakage barrier layer 107 in the following order.

[0265] The doping layer 234 may be disposed between the second hafnium oxide layer 245B and the second seed layer 246B. The doping layer 234 may not separate the grains of the second hafnium oxide layer 245B and the grains of the second seed layer 246B.

[0266] The doping layer 234 may be embedded in the second seed layer 246B. In other words, it may be embedded in the bottom surface of the second seed layer 246B in contact with the second hafnium oxide layer 245B. Therefore, the doping layer 234 may be, for example, aluminum-doped tetragonal zirconium oxide or beryllium-doped tetragonal zirconium oxide.

[0267] According to another embodiment of the present invention, the doping layer 234 may be embedded on the top surface of the second hafnium oxide layer 245B. Therefore, the doping layer 234 may be, for example, aluminum-doped tetragonal hafnium oxide or beryllium-doped tetragonal hafnium oxide.

[0268] The crystallization of the first to third hafnium oxide layers 245A, 245B, and 245C may be promoted by the first to third seed layers 246A, 246B, and 246C. The dielectric constant of the first hafnium oxide layer 245A may be improved by the first reinforcement layer KBL1. The dielectric constant of the second hafnium oxide layer 245B may be improved by the second reinforcement layer KBL2. The dielectric constant of the third hafnium oxide layer 245C may be improved by the third reinforcement layer KBL3. The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 245A. The second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 245B. The third reinforcement layer KBL2 may be formed under the third hafnium oxide layer 245C. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 245A. The second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 245B. The third reinforcement layer KBL3 may directly contact the third hafnium oxide layer 245C.

[0269] Reference Fig. 12A , the semiconductor device 119A may include a first electrode 101 , a multilayer stack DE36 , a heat source layer 103 , and a second electrode 102 .

[0270] The multilayer stack DE36 may be or include a stack of a first reinforcement layer KBL1, a first hafnium oxide layer 255A, a first seed layer 256A, a doping layer 254, a second reinforcement layer KBL2, a second hafnium oxide layer 255B, a second seed layer 256B, and a leakage barrier layer 107 in the following order.

[0271] The second reinforcement layer KBL2 may be disposed between the first seed layer 256A and the second hafnium oxide layer 255B. The doping layer 254 may be disposed between the first seed layer 256A and the second reinforcement layer KBL2. The doping layer 254 may be embedded on the top surface of the first seed layer 256A. Therefore, the second reinforcement layer KBL2 may be disposed between the first seed layer 256A in which the doping layer 254 is embedded and the second hafnium oxide layer 255B. The doping layer 254 may be much thinner than the second reinforcement layer KBL2 and the second hafnium oxide layer 255B.

[0272] The crystallization of the first and second hafnium oxide layers 255A and 255B may be promoted by the first and second seed layers 256A and 256B. The dielectric constant of the first hafnium oxide layer 255A may be improved by the first reinforcement layer KBL1. The dielectric constant of the second hafnium oxide layer 255B may be improved by the second reinforcement layer KBL2. The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 255A. The second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 255B. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 255A. The second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 255B.

[0273] Reference Fig. 12B , the semiconductor device 119A′ may include a first electrode 101 , a multilayer stack DE36 ′, a heat source layer 103 , and a second electrode 102 .

[0274] The multilayer stack DE36' may be or include a stack of a first enhancement layer KBL1, a first hafnium oxide layer 255A, a first seed layer 256A, a doping layer 254, a second enhancement layer KBL2, a second hafnium oxide layer 255B, a second seed layer 256B, a third hafnium oxide layer 255C and a leakage barrier layer 107 in the following order.

[0275] The second enhancement layer KBL2 may be disposed between the first seed layer 256A and the second hafnium oxide layer 255B. The doping layer 254 may be disposed between the first seed layer 256A and the second enhancement layer KBL2. The doping layer 254 may be embedded on the top surface of the first seed layer 256A. Therefore, the second enhancement layer KBL2 may be disposed between the first seed layer 256A having the doping layer 254 and the second hafnium oxide layer 255B. The doping layer 254 may be much thinner than the second enhancement layer KBL2 and the second hafnium oxide layer 255B.

[0276] The crystallization of the first to third hafnium oxide layers 255A, 255B, and 255C may be promoted by the first and second seed layers 256A and 256B. The dielectric constant of the first hafnium oxide layer 255A may be improved by the first enhancement layer KBL1. The dielectric constant of the second hafnium oxide layer 255B may be improved by the second enhancement layer KBL2. The first enhancement layer KBL1 may be formed under the first hafnium oxide layer 255A. The second enhancement layer KBL2 may be formed under the second hafnium oxide layer 255B. The first enhancement layer KBL1 may directly contact the first hafnium oxide layer 255A. The second enhancement layer KBL2 may directly contact the second hafnium oxide layer 255B. According to another embodiment of the present invention, a third enhancement layer may be further formed between the second seed layer 256B and the third hafnium oxide layer 255C.

[0277] Reference Fig. 12C, the semiconductor device 119B may include a first electrode 101 , a multilayer stack DE37 , a heat source layer 103 , and a second electrode 102 .

[0278] The multilayer stack DE37 can be or include a stack of a first seed layer 266A, a first reinforcement layer KBL1, a first hafnium oxide layer 265A, a second seed layer 266B, a doping layer 254, a second reinforcement layer KBL2, a second hafnium oxide layer 265B, a second seed layer 266C, a third reinforcement layer KBL3, a third hafnium oxide layer 265C and a leakage blocking layer 107 in the following order.

[0279] The second reinforcement layer KBL2 may be disposed between the second seed layer 266B and the second hafnium oxide layer 265B. The doping layer 254 may be disposed between the second seed layer 266B and the second reinforcement layer KBL2. The doping layer 254 may be embedded on the top surface of the second seed layer 266B. Therefore, the second reinforcement layer KBL2 may be disposed between the second seed layer 266B having the doping layer 254 and the second hafnium oxide layer 265B. The doping layer 254 may be much thinner than the second reinforcement layer KBL2 and the second hafnium oxide layer 265B.

[0280] The crystallization of the first to third hafnium oxide layers 265A, 265B, and 265C may be promoted by the first to third seed layers 266A, 266B, and 266C. The dielectric constant of the first hafnium oxide layer 265A may be improved by the first reinforcement layer KBL1. The dielectric constant of the second hafnium oxide layer 265B may be improved by the second reinforcement layer KBL2. The dielectric constant of the third hafnium oxide layer 265C may be improved by the third reinforcement layer KBL3. The first reinforcement layer KBL1 may be formed under the first hafnium oxide layer 265A. The second reinforcement layer KBL2 may be formed under the second hafnium oxide layer 265B. The third reinforcement layer KBL3 may be formed under the third hafnium oxide layer 265C. The first reinforcement layer KBL1 may directly contact the first hafnium oxide layer 265A. The second reinforcement layer KBL2 may directly contact the second hafnium oxide layer 265B. The third reinforcement layer KBL3 may directly contact the third hafnium oxide layer 265C.

[0281] Reference Fig.13A , the semiconductor device 120A may include a first electrode 101 , a multilayer stack DE38 , a heat source layer 103 , and a second electrode 102 .

[0282] The multilayer stack DE38 may be or include a stack of an alternating stack and a leakage barrier layer 107 in the order described. In the alternating stack, the reinforcement layer KBL, the hafnium oxide layer 275, and the seed layer 276 may be alternately stacked. The reinforcement layer KBL may be formed under each hafnium oxide layer 275. The hafnium oxide layer 275 may be disposed between the reinforcement layer KBL and the seed layer 276. In the alternating stack, the reinforcement layer KBL, the hafnium oxide layer 275, and the seed layer 276 may be alternately stacked at least twice. Fig.13A A case is shown in which the reinforcement layer KBL, the hafnium oxide layer 275, and the seed layer 276 are alternately stacked three times.

[0283] The enhancement layer KBL may directly contact the hafnium oxide layer 275. Crystallization of the hafnium oxide layer 275 may be promoted by the seed layer 276. The dielectric constant of the hafnium oxide layer 275 may be improved by the enhancement layer KBL.

[0284] Reference Fig. 13B , the semiconductor device 120B may include a first electrode 101 , a multilayer stack DE39 , a heat source layer 103 , and a second electrode 102 .

[0285] The multilayer stack DE39 may be or include a stack of alternating stacks, leakage barrier layers 107 and interface control layers 108. In the alternating stacks, the reinforcement layer KBL, the hafnium oxide layer 275 and the seed layer 276 may be alternately stacked multiple times. The reinforcement layer KBL may be formed under each hafnium oxide layer 275.

[0286] The enhancement layer KBL may directly contact the hafnium oxide layer 275. Crystallization of the hafnium oxide layer 275 may be promoted by the seed layer 276. The dielectric constant of the hafnium oxide layer 275 may be improved by the enhancement layer KBL.

[0287] Fig.14A and Fig. 14B is a cross-sectional view illustrating an example of a method for manufacturing a semiconductor device.

[0288] Reference Fig.14A , a first electrode 11 may be formed over the substrate 10, and an enhancement layer KBL may be formed over the first electrode 11. The enhancement layer KBL may be formed of niobium oxynitride. The enhancement layer KBL may be formed by atomic layer deposition (ALD). For example, atomic layer deposition of niobium oxynitride may include a unit cycle including supplying a niobium source material, purging, supplying an oxidizing gas, purging, supplying a nitride gas, and purging. The niobium source material may include a cyclopentadienyl (Cp)-based alkylamide source or a Cl-based source. The oxidizing gas may include O2 or O3, and the nitriding gas may include NH3, N2, or N2 / H2 plasma. The atomic layer deposition of niobium oxynitride may be performed at a temperature of about 250 to 400° C. and a pressure of about 0.5 to 2 Torr.

[0289] An initial hafnium oxide layer 12' may be formed over the enhancement layer KBL. The initial hafnium oxide layer 12' may be deposited by an atomic layer deposition (ALD) method. For example, after the substrate 10 having the first electrode 11 formed thereon is loaded into an atomic layer deposition chamber, a deposition process of the enhancement layer KBL and the initial hafnium oxide layer 12' may be performed.

[0290] The initial hafnium oxide layer 12' may include an amorphous structure, a monoclinic crystal structure, or a mixed crystal structure in which the amorphous structure and the monoclinic crystal structure are uniformly or non-uniformly mixed.

[0291] As described above, the initial hafnium oxide layer 12 ′ may be formed to have a non-tetragonal crystal structure.

[0292] Subsequently, a seed layer 13 may be formed over the initial hafnium oxide layer 12'. The seed layer 13 may include zirconium oxide. The seed layer 13 may be formed by atomic layer deposition. The seed layer 13 may be thicker than the initial hafnium oxide layer 12'. As described in the above embodiments of the present invention, the seed layer 13 may include a doped layer embedded therein, or may not include a doped layer embedded therein.

[0293] After forming the seed layer 13, the initial hafnium oxide layer 12' may maintain the initial crystal structure without phase change. Due to the deposition temperature of the seed layer 13, the initial hafnium oxide layer 12' may not be crystallized into a tetragonal crystal structure.

[0294] Reference Fig. 14B , a heat source layer 14 may be formed over the seed layer 13. The heat source layer 14 may be formed at a temperature at which the initial hafnium oxide layer 12' may be crystallized into a tetragonal crystal structure. The formation of the heat source layer 14 may provide the initial hafnium oxide layer 12' with the thermal energy required to cause a phase change of the initial hafnium oxide layer 12'. The heat source layer 14 may be formed by atomic layer deposition (ALD) at a low temperature of about 500° C. or less. For example, when depositing the heat source layer 14, low-temperature thermal energy may be provided to the substrate 10, and the initial hafnium oxide layer 12' may be crystallized into a tetragonal crystal structure by the low-temperature thermal energy provided to the substrate 10 and the seed layer 13. The seed layer 13 may also be crystallized into a tetragonal crystal structure by a low-temperature process.

[0295] Although not shown, after forming the heat source layer 14, a second electrode (not shown) may be formed over the heat source layer 14. According to another embodiment of the present invention, the heat source layer 14 may be used as the second electrode. According to another embodiment of the present invention, a leakage barrier layer and an interface control layer may be further formed before forming the heat source layer 14.

[0296] Fig.15A and Fig. 15Bis a cross-sectional view illustrating another example of a method for manufacturing a semiconductor device.

[0297] Reference Fig.15A , a first electrode 11 may be formed over the substrate 10, a seed layer 13 may be formed over the first electrode 11, and the seed layer 13 may be formed by atomic layer deposition (ALD). For example, a deposition process of the seed layer 13 may be performed after the substrate 10 having the first electrode 11 formed thereon is loaded into an atomic layer deposition chamber. The seed layer 13 may be or include tetragonal zirconia.

[0298] The enhancement layer KBL and the initial hafnium oxide layer 12' may be formed over the seed layer 13. The enhancement layer KBL and the initial hafnium oxide layer 12' may be deposited by atomic layer deposition (ALD). The initial hafnium oxide layer 12' may include an amorphous structure, a monoclinic crystal structure, or a mixed crystal structure. In the mixed crystal structure, the amorphous structure and the monoclinic crystal structure are uniformly or non-uniformly mixed.

[0299] As described above, the initial hafnium oxide layer 12 ′ may be formed to have a non-tetragonal crystal structure.

[0300] Although the initial hafnium oxide layer 12' is deposited over the enhancement layer KBL, the initial hafnium oxide layer 12' may maintain the initial crystal structure without phase change. The seed layer 13 may be thicker than the initial hafnium oxide layer 12'. As described in the above embodiments of the present invention, the seed layer 13 may be formed with a doping layer embedded therein, or may not be formed with a doping layer embedded therein.

[0301] like Fig. 15B As shown, the heat source layer 14 can be formed above the initial hafnium oxide layer 12'. The heat source layer 14 can be formed at a temperature at which the initial hafnium oxide layer 12' can be crystallized into a tetragonal crystal structure. The heat source layer 14 can provide thermal energy, which can cause a phase change of the initial hafnium oxide layer 12'. The heat source layer 14 can be formed by atomic layer deposition (ALD) at a low temperature of about 500°C or less. For example, when depositing the heat source layer 14, low-temperature thermal energy can be provided to the substrate 10, and the initial hafnium oxide layer 12' can be crystallized into a tetragonal crystal structure by the low-temperature thermal energy provided to the substrate 10 and the seed layer 13. The seed layer 13 can also be crystallized into a tetragonal crystal structure by the low-temperature thermal energy provided to the substrate 10.

[0302] Although not shown, after forming the heat source layer 14, a second electrode (not shown) may be formed over the heat source layer 14. According to another embodiment of the present invention, the heat source layer 14 may be used as the second electrode. According to another embodiment of the present invention, a leakage barrier layer and an interface control layer may be further formed before forming the heat source layer 14.

[0303] Reference FIG. 14A to FIG. 15BWhen the heat source layer 14 is formed, the crystallization of the initial hafnium oxide layer 12 ′ may be accelerated by the seed layer 13 , so that the initial hafnium oxide layer 12 ′ may be crystallized into the tetragonal hafnium oxide layer 12 .

[0304] The crystallinity of the hafnium oxide layer 12 may also depend on the thickness of the heat source layer 14. The thickness of the heat source layer 14 may be about 20 to 1000 Å.

[0305] As described above, the seed layer 13 can allow the initial hafnium oxide layer 12' to be fully crystallized into a tetragonal crystal structure when the heat source layer 14 is deposited. In addition, the dielectric constant of the hafnium oxide layer 12 can be improved by the enhancement layer KBL.

[0306] The stacking of the seed layer 13 and the initial hafnium oxide layer 12' can be obtained by various methods. For example, a single seed layer 13 can be formed between two initial hafnium oxide layers 12'. A single layer of the initial hafnium oxide layer 12' can be formed between two seed layers 13. Multiple seed layers 13 and multiple initial hafnium oxide layers 12' can be alternately stacked.

[0307] Fig.16A and Fig. 16B is a cross-sectional view illustrating another example of a method for manufacturing a semiconductor device.

[0308] Reference Fig.16A , a first electrode 11 may be formed over the substrate 10, and a first enhancement layer KBL1, a first initial hafnium oxide layer 12A and a seed layer 13, a second enhancement layer KBL2, and a second initial hafnium oxide layer 12B may be sequentially formed over the first electrode 11. The first enhancement layer KBL1, the first initial hafnium oxide layer 12A, the seed layer 13, the second enhancement layer KBL2, and the second initial hafnium oxide layer 12B may be formed by atomic layer deposition (ALD). For example, after the substrate 10 on which the first electrode 11 is formed is loaded into an atomic layer deposition chamber, atomic layer deposition of the first enhancement layer KBL1, the first initial hafnium oxide layer 12A, the seed layer 13, the second enhancement layer KBL2, and the second initial hafnium oxide layer 12B may be performed. The seed layer 13 may be thicker than the first and second initial hafnium oxide layers 12A and 12B. As described in the above-mentioned embodiments of the present invention, the seed layer 13 may be formed to have a doping layer embedded therein, or may be formed to have no doping layer embedded therein.

[0309] The first and second initial hafnium oxide layers 12A and 12B may include an amorphous structure, a monoclinic crystal structure, or a mixed crystal structure in which the amorphous structure and the monoclinic crystal structure are uniformly or non-uniformly mixed.

[0310] As described above, the first and second initial hafnium oxide layers 12A and 12B may have a non-tetragonal crystal structure. The seed layer 13 may be made of a material having a tetragonal crystal structure.

[0311] Reference Fig. 16B , a heat source layer 14 may be formed over the second initial hafnium oxide layer 12B. The heat source layer 14 may be formed at a temperature at which the first and second initial hafnium oxide layers 12A and 12B may be crystallized into a tetragonal crystal structure. The heat source layer 14 may provide thermal energy, which may cause a phase change of the first and second initial hafnium oxide layers 12A and 12B. The heat source layer 14 may be formed by atomic layer deposition (ALD) at a low temperature of about 500° C. or less. For example, low-temperature thermal energy may be provided to the substrate 10 when the heat source layer 14 is deposited, and the first and second initial hafnium oxide layers 12A and 12B may be crystallized into a tetragonal crystal structure by the low-temperature thermal energy provided to the substrate 10 and the seed layer 13. The seed layer 13 may also be crystallized into a tetragonal crystal structure by the low-temperature thermal energy provided to the substrate 10.

[0312] Although not shown, after the heat source layer 14 is formed, a second electrode may be formed over the heat source layer 14 .

[0313] Reference Fig. 16B When the heat source layer 14 is formed, the crystallization of the first and second initial hafnium oxide layers 12A and 12B may be promoted by the seed layer 13 (see reference numeral 13S). Therefore, the first and second initial hafnium oxide layers 12A and 12B may be crystallized into the tetragonal hafnium oxide layer 12. Moreover, the first and second enhancement layers KBL1 and KBL2 may improve the dielectric constant of the hafnium oxide layer 12.

[0314] exist FIG. 14A to FIG. 16B In the embodiment of the present invention, the heat source layer 14 may have a strong tensile stress. For example, it may have a tensile stress of about 0.5 GPa to 2.0 GPa. The strong tensile stress may promote the crystallization of the tetragonal hafnium oxide layer 12.

[0315] Fig.17A and Fig. 17B It is the description of the formation FIG. 14A to FIG. 16B Flow chart of an example of a method for forming a seed layer as shown. The seed layer 13 may be a zirconium oxide layer, and the zirconium oxide layer may be formed by atomic layer deposition (ALD). The seed layer 13 may correspond to Figure 2BThe seed layer 106 may include a doping layer embedded therein. The seed layer 13 may include a "Z-AZ-Z stack" in which a first zirconium oxide layer, an aluminum-doped zirconium oxide layer, and a second zirconium oxide layer are sequentially stacked. The Z-AZ-Z stack may be different from a ZAZ stack in which a first zirconium oxide layer, an aluminum oxide layer, and a second zirconium oxide layer are sequentially stacked. In the Z-AZ-Z stack, the aluminum-doped zirconium oxide layer may not separate the grains of the first zirconium oxide layer and the grains of the second zirconium oxide layer. In contrast, in the ZAZ stack, the aluminum oxide layer may separate the grains of the first zirconium oxide layer and the grains of the second zirconium oxide layer.

[0316] Reference Fig.17A , the atomic layer deposition method of Z-AZ-Z stack is as follows.

[0317] The atomic layer deposition of the Z-AZ-Z stack can be performed by repeating a plurality of cycles at about 250°C to 380°C. Here, the plurality of cycles may include a first cycle Z1 for depositing a first zirconium oxide layer, a second cycle Z2 for depositing an aluminum-doped zirconium oxide layer, and a third cycle Z3 for depositing a second zirconium oxide layer. The first cycle Z1 may be repeated A times to deposit the first zirconium oxide layer, and the second cycle Z2 may be repeated B times to deposit the aluminum-doped zirconium oxide layer. The third cycle Z3 may be repeated C times to deposit the second zirconium oxide layer. Here, A, B, and C may be different natural numbers, and B may be less than A and C. For example, B may be a number between 1 and 10, and A and C may be greater than 10. A and C may be the same to deposit the first zirconium oxide layer and the second zirconium oxide layer of the same thickness. According to another embodiment of the present invention, C may be greater than A to deposit a second zirconium oxide layer thicker than the first zirconium oxide layer.

[0318] The first cycle Z1 , the second cycle Z2 , and the third cycle Z3 may be performed at about 250° C. to 380° C., thereby easily depositing the seed layer 13 having a tetragonal crystal structure.

[0319] The first cycle Z1 may include a Zr source adsorption step S1, a purge step S2, a reaction gas supply step S3, and an unreacted gas purge step S4. The first cycle Z1 may be repeated A times. An undoped first zirconium oxide layer may be deposited through the first cycle Z1.

[0320] The second cycle Z2 may include a Zr source adsorption step S21, a purge step S22, an Al source adsorption step S23, a purge step S24, a reaction gas supply step S25, and an unreacted gas purge step S26. The second cycle Z2 may be repeated B times. An aluminum-doped zirconium oxide layer may be deposited by the second cycle Z2.

[0321] The third cycle Z3 may include a Zr source adsorption step S31, a purge step S32, a reaction gas supply step S33, and an unreacted gas purge step S34, and may be repeatedly performed C times. An undoped second zirconium oxide layer may be deposited through the third cycle Z3.

[0322] In the first cycle Z1, the second cycle Z2, and the third cycle Z3, the Zr source may include TEMAZ (tetraethyl methylamino zirconium) and TDMAZ (tetradimethylamino zirconium), and the Al source may include TMA (trimethylaluminum), and the reaction gas may include an oxidant. The oxidant may include O3, O2, H2O, H2O2, O2 plasma, or a combination thereof. When ozone (O3) is used as an oxidant, the concentration and flow rate of ozone may be optimized and supplied. For example, about 50 g / m 3 Up to 310g / m 3 Ozone is used at a concentration of about 100 sccm to about 5000 sccm. The purge step may be long enough, in the range of about 1 second to about 100 seconds.

[0323] A structure in which aluminum (Al) is doped in the zirconium oxide layer may be obtained through the first cycle Z1 , the second cycle Z2 , and the third cycle Z3 .

[0324] Reference Fig. 17B , describes another embodiment of the present invention, in which the second cycle Z2' may include only the Al source adsorption step S23' and the purge step S24'. For example, after the first zirconium oxide layer is deposited by the first cycle Z1, the Al source adsorption step S23' and the purge step S24' may be repeatedly performed a predetermined number of times to adsorb aluminum on the surface of the first zirconium oxide layer, and then by performing the third cycle Z3, the second zirconium oxide layer may be deposited. Even if aluminum is adsorbed as described above, the grains of the first zirconium oxide layer and the grains of the second zirconium oxide layer may not be separated.

[0325] The first cycle Z1 or the third cycle Z3 may be used to deposit a seed layer in which no doping layer is embedded.

[0326] Fig.18A It is a description of the formation FIG. 14A to FIG. 16B A flow chart of an example of a method of forming an initial hafnium oxide layer is shown.

[0327] like Fig.18AAs shown, the initial hafnium oxide layer 12' may be a hafnium oxide layer having a doped layer embedded therein. The initial hafnium oxide layer 12' may be formed by atomic layer deposition (ALD). The initial hafnium oxide layer 12' may include a "H-AH-H stack" in which a first hafnium oxide layer, a doped layer, and a second hafnium oxide layer are sequentially stacked. The H-AH-H stack may be different from a HAH stack in which a first hafnium oxide layer, an aluminum oxide layer, and a second hafnium oxide layer are sequentially stacked. In the H-AH-H stack, the aluminum-doped hafnium oxide layer does not separate the grains of the first hafnium oxide layer and the grains of the second hafnium oxide layer. In contrast, in the HAH stack, the aluminum oxide layer separates the grains of the first hafnium oxide layer and the grains of the second hafnium oxide layer.

[0328] Reference Fig.18A , the following describes an atomic layer deposition method of an H—AH—H stack as a hafnium oxide layer having a doping layer embedded therein.

[0329] The atomic layer deposition of the H-AH-H stack may be performed by repeating a plurality of cycles at about 250°C to 380°C. Here, the plurality of cycles may include a first cycle H1 for depositing a first hafnium oxide layer, a second cycle H2 for depositing an aluminum-doped hafnium oxide layer, and a third cycle H3 for depositing a second hafnium oxide layer. The first cycle H1 may be repeated A times to deposit the first hafnium oxide layer, and the second cycle H2 may be repeated B times to deposit the aluminum-doped hafnium oxide layer. The third cycle H3 may be repeated C times to deposit the second hafnium oxide layer. Here, A, B, and C may be different natural numbers, and B may be less than A and C. For example, B may be a number between 1 and 10, and A and C may be greater than 10. A and C may be the same so as to deposit the first oxide layer and the second hafnium oxide layer of the same thickness. According to another embodiment of the present invention, A may be made greater than C to deposit a first hafnium oxide layer thicker than the second hafnium oxide layer.

[0330] The first cycle H1 , the second cycle H2 , and the third cycle H3 may be performed at about 250° C. to 380° C., thereby easily depositing the hafnium oxide layer.

[0331] The first cycle H1 may include a Hf source adsorption step S41, a purge step S42, a reaction gas supply step S43, and an unreacted gas purge step S44, and may be repeatedly performed A times. An undoped first hafnium oxide layer may be deposited through the first cycle H1.

[0332] The second cycle H2 may include a Hf source adsorption step S51, a purge step S52, an Al source adsorption step S53, a purge step S54, a reaction gas supply step S55, and an unreacted gas purge step S56, and the second cycle H2 may be repeated B times. An aluminum-doped hafnium oxide layer may be deposited in the second cycle H2.

[0333] The third cycle H3 may include a Hf source adsorption step S61, a purge step S62, a reaction gas supply step S63, and an unreacted gas purge step S64. The third cycle H3 may be repeated C times. An undoped second hafnium oxide layer may be deposited through the third cycle H3.

[0334] In the first cycle H1, the second cycle H2 and the third cycle H3, the Hf source may include TEMAH (tetraethylmethylamino hafnium), TDEAH (tetradiethylamino hafnium), TDMAH (tetradimethylamino hafnium), etc. Moreover, the Al source may include TMA (trimethylaluminum), and the reaction gas may include an oxidant. The oxidant may include O3, O2, H2O, H2O2, O2 plasma or a combination thereof. When ozone (O3) is used as an oxidant, the concentration and flow rate of ozone may be optimized and supplied. For example, it may be supplied at about 50 g / m 3 Up to 310g / m 3 Ozone is used at a concentration of about 100 sccm to about 5000 sccm, and the flow rate of ozone can be in the range of about 100 sccm to about 5000 sccm. The purge step can be long enough, in the range of about 1 second to about 100 seconds.

[0335] A structure in which aluminum (Al) is doped in the hafnium oxide layer may be obtained through the first cycle H1 , the second cycle H2 , and the third cycle H3 .

[0336] The first cycle H1 or the third cycle H3 may be used to deposit an initial hafnium oxide layer in which no doping layer is embedded.

[0337] According to another embodiment of the present invention, the second cycle H2 may include only the Al source adsorption step S53 and the purge step S54. For example, after the first hafnium oxide layer is deposited through the first cycle H1, only the Al source adsorption step S53 and the purge step S54 may be repeated a predetermined number of times to adsorb aluminum onto the surface of the first hafnium oxide layer. Then, the second hafnium oxide layer may be deposited by performing the third cycle H3. Even when aluminum is adsorbed, the grains of the first hafnium oxide layer and the grains of the second hafnium oxide layer may not be separated.

[0338] Fig.18B is used to describe the formation FIG. 14A to FIG. 16B Flow chart of an example of a method of stacking a seed layer and an initial hafnium oxide layer as shown in FIG. Fig.18B An atomic layer deposition method of a ZH stack as a stack of a seed layer and an initial hafnium oxide layer is shown.

[0339] The atomic layer deposition of the ZH stack may be performed by repeating a plurality of cycles at about 250° C. to 380° C. Here, the plurality of cycles may include a first cycle Z11 for depositing a zirconium oxide layer as the seed layer 13 and a second cycle H11 for depositing an initial hafnium oxide layer 12′. The zirconium oxide layer may be deposited by repeating the first cycle Z11 A times, and the initial hafnium oxide layer may be deposited by repeating the second cycle H11 B times.

[0340] The first cycle Z11 may include a Zr source adsorption step S1, a purging step S2, a reaction gas supply step S3, and an unreacted gas purging step S4. The first cycle Z11 may be repeated A times. An undoped zirconium oxide layer may be deposited by the first cycle Z11. According to another embodiment of the present invention, after the first cycle Z11, Fig.17A The second cycle Z2 or Fig. 17B As a result, an aluminum-doped zirconium oxide layer can be deposited.

[0341] The second cycle H11 may include a Hf source adsorption step S41, a purge step S42, a reaction gas supply step S43, and an unreacted gas purge step S44. The second cycle H11 may be repeated B times. An undoped hafnium oxide layer may be deposited through the second cycle H11.

[0342] According to another embodiment of the present invention, after the first cycle Z11, the following may be performed: Fig.17A The second cycle Z2 of FIG. 17 or the second cycle Z2′ of FIG. 17 is performed to deposit the aluminum-doped zirconium oxide layer.

[0343] According to another embodiment of the present invention, before executing the second loop H11, Fig.18A As a result, an aluminum-doped hafnium oxide layer can be deposited.

[0344] Although not shown, Fig.18A and Fig.18B In the embodiment, the cycle for depositing the enhancement layer KBL may be performed before the cycles H1 and H11 for depositing the hafnium oxide layer.

[0345] The dielectric layer stack according to the above-described embodiment of the present invention can be formed by combining FIG. 17A to FIG. 18B For example, Figure 4A The stack of the first hafnium oxide layer 105A, the seed layer 106 having the doping layer 104, and the second hafnium oxide layer 105B is shown. Fig.18A The first cycle H1 of the second hafnium oxide layer 105B and the initial hafnium oxide layer of the first hafnium oxide layer 105A are deposited. Fig.17AThe seed layer 106 in which the doping layer 104 is embedded is deposited through the first to third cycles Z1 to Z3.

[0346] Fig.19A and Fig.19B is a cross-sectional view showing a method for crystallizing an initial hafnium oxide according to a comparative embodiment. The initial hafnium oxide layer 12 ′ according to the comparative embodiment may be deposited by atomic layer deposition (ALD) and may be a single hafnium oxide layer (HfO 2 ) without a seed layer 13 .

[0347] like Fig.19A As shown, in the comparative example 1 without the seed layer 13 and the heat source layer 14, a high temperature heat treatment (12H) of about 900°C or higher may be additionally required to crystallize the initial hafnium oxide layer 12' into tetragonal hafnium oxide. Even if the high temperature heat treatment 12H is performed, the initial hafnium oxide layer 12' can hardly be crystallized into pure tetragonal hafnium oxide. In other words, after the high temperature heat treatment 12H, the initial hafnium oxide layer 12' may not be crystallized into a pure tetragonal crystal structure, but may be crystallized into a tetragonal crystal structure and a monoclinic crystal structure mixed together. In addition, even if the high temperature heat treatment 12H is performed, it can be stabilized into a monoclinic crystal structure having a relatively lower dielectric constant than the tetragonal crystal structure. In addition, after the high temperature heat treatment, a rapid quenching process of about 1ms or less is required.

[0348] Reference Fig.19B In Comparative Example 2 without the seed layer 13, it is difficult to completely crystallize the initial hafnium oxide layer 12' into tetragonal hafnium oxide by depositing the heat source layer 14. Therefore, in Comparative Example 2, in order to crystallize the initial hafnium oxide layer 12' into tetragonal hafnium oxide, a high-temperature heat treatment 12H of about 900°C or more may be required after the deposition of the heat source layer 14. In Comparative Example 2, which is different from Comparative Example 1, the initial hafnium oxide layer 12' may be crystallized into a hafnium oxide layer 12 having a pure tetragonal crystal structure through the heat source layer 14 and the high-temperature heat treatment 12H. However, Comparative Example 2 may deteriorate the characteristics of the capacitor and the surrounding structure through the high-temperature heat treatment 12H.

[0349] As described above, it is difficult to form pure tetragonal hafnium oxide using a single hafnium oxide.

[0350] According to an embodiment of the present invention, the seed layer 13 and the heat source layer 14 may be applied and the seed layer 13 and the initial hafnium oxide layer 12 ′ may be formed to be in direct contact with each other. Therefore, when the heat source layer 14 is deposited, the initial hafnium oxide layer 12 ′ may be fully crystallized into the hafnium oxide layer 12 .

[0351] According to an embodiment of the present invention, the hafnium oxide layer 12 having a pure tetragonal crystal structure may be formed at a low temperature without performing a high temperature heat treatment. The hafnium oxide layer 12 having a pure tetragonal crystal structure may have a high dielectric constant of about 60 or more.

[0352] The dielectric constant of the hafnium oxide layer 12 having a pure tetragonal crystal structure may be greater than the dielectric constant of tetragonal zirconium oxide (approximately 40). As a result, the capacitance of the capacitor may be increased.

[0353] In addition, since the hafnium oxide layer 12 is formed at a low temperature, the characteristics of the capacitor and the peripheral structure are not deteriorated.

[0354] Figures 20A to 20C A storage unit is shown. Fig. 20B It is along Fig. 20A A cross-sectional view taken along line AA'. Fig. 20C is along Fig. 20A A cross-sectional view taken along line BB'.

[0355] The memory cell 500 may include a cell transistor including a buried word line 508, a bit line 514, and a capacitor 600. The capacitor 600 may include a dielectric layer stack, which may include one of the dielectric layer stacks of the above-described embodiments of the present invention.

[0356] The storage unit 500 will be described in detail below.

[0357] The isolation layer 503 and the active area 504 may be formed in the substrate 501. A plurality of active areas 504 may be defined by the isolation layer 503. The substrate 501 may be made of a material suitable for a semiconductor process. The substrate 501 may include a semiconductor substrate. The substrate 501 may be formed of a material containing silicon. The substrate 501 may be or include silicon, single crystal silicon, polycrystalline silicon, amorphous silicon, silicon germanium, single crystal silicon germanium, polycrystalline silicon germanium, carbon-doped silicon, a combination thereof or a multilayer thereof. The substrate 501 may include other semiconductor materials such as germanium. The substrate 501 may include a III / V semiconductor substrate, for example a composite semiconductor substrate such as GaAs. The substrate 501 may be or include a silicon on insulator (SOI) substrate. The isolation layer 503 may be formed in the isolation trench 502 by a shallow trench isolation (STI) process.

[0358] A word line trench 506 may be formed in the substrate 501. The word line trench 506 may be referred to as a gate trench. A gate dielectric layer 507 may be formed on the surface of the word line trench 506. A buried word line 508 may be formed above the gate dielectric layer 507 to partially fill the word line trench 506. The buried word line 508 may be referred to as a buried gate electrode. A word line capping layer 509 may be formed above the buried word line 508. The top surface of the buried word line 508 may be lower than the surface of the substrate 501. The buried word line 508 may be a low-resistance metal material. In the buried word line 508, titanium nitride and tungsten may be sequentially stacked. According to another embodiment of the present invention, the buried word line 508 may be formed only of titanium nitride (only TiN).

[0359] The first and second impurity regions 510 and 511 may be formed in the substrate 501. The first and second impurity regions 510 and 511 may be separated from each other by the word line trench 506. The first and second impurity regions 510 and 511 may be referred to as first and second source / drain regions. The first and second impurity regions 510 and 511 may include N-type impurities such as arsenic (As) or phosphorus (P). As a result, the buried word line 508 and the first and second impurity regions 510 and 511 may be cell transistors. The cell transistor may improve the short channel effect by burying the word line 508.

[0360] The bit line contact plug 513 may be formed over the substrate 501. The bit line contact plug 513 may be coupled to the first impurity region 510. The bit line contact plug 513 may be disposed in the bit line contact hole 512. The bit line contact hole 512 may be formed in the hard mask layer 505. The hard mask layer 505 may be formed over the substrate 501. The bit line contact hole 512 may expose the first impurity region 510. The bottom surface of the bit line contact plug 513 may be lower than the top surface of the substrate 501. The bit line contact plug 513 may be formed of polysilicon or a metal material. A portion of the bit line contact plug 513 may have a line width smaller than a diameter of the bit line contact hole 512. The bit line 514 may be formed over the bit line contact plug 513. The bit line hard mask 515 may be formed over the bit line 514. The stacked structure of the bit line 514 and the bit line hard mask 515 may be referred to as a bit line structure BL. The bit line 514 may have a line shape extending in a direction intersecting the buried word line 508. A portion of the bit line 514 may be coupled to the bit line contact plug 513. The bit line 514 may be or include a metal material. The bit line hard mask 515 may include a dielectric material.

[0361] The bit line spacer 516 may be formed on the sidewall of the bit line structure BL. The bottom of the bit line spacer 516 may extend to be formed on both sidewalls of the bit line contact plug 513. The bit line spacer 516 may be or include silicon oxide, silicon nitride, or a combination thereof. According to another embodiment of the present invention, the bit line spacer 516 may include an air gap. For example, it may have a NAN (nitride-air gap-nitride) structure in which an air gap is provided between silicon nitrides.

[0362] The storage node contact plug SNC may be formed between adjacent bit line structures BL. The storage node contact plug SNC may be formed in the storage node contact hole 518. The storage node contact plug SNC may be coupled to the second impurity region 511. The storage node contact plug SNC may include a lower plug 519 and an upper plug 521. The storage node contact plug SNC may further include an ohmic contact layer 520 between the lower plug 519 and the upper plug 521. The ohmic contact layer 520 may include metal silicide. The upper plug 521 may be or include a metal material, and the lower plug 519 may be or include a silicon-containing material.

[0363] From the perspective of a direction parallel to the bit line structure BL, a plug isolation layer 517 may be formed between adjacent storage node contact plugs SNC. The plug isolation layer 517 may be formed between adjacent bit line structures BL and may provide a storage node contact hole 518 together with the hard mask layer 505.

[0364] FIG. 21A to FIG. 21F An application example of a capacitor of a memory cell is shown.

[0365] Reference Fig.21A , the capacitor 611 may include a bottom electrode 601, a multilayer stack 600D, a heat source layer 603, and a top electrode 602. The bottom electrode 601 may have a cylindrical shape. The multilayer stack 600D may be formed above the bottom electrode 601, and the heat source layer 603 may be formed above the multilayer stack 600D. The top electrode 602 may be formed above the heat source layer 603. The multilayer stack 600D may correspond to one of the multilayer stacks of the above-described embodiments of the present invention. Therefore, for example, the multilayer stack 600D may be or include a stack of an enhancement layer, a hafnium oxide layer, a seed layer, and a leakage barrier layer. According to another example, the multilayer stack 600D may be or include a stack of an enhancement layer, a hafnium oxide layer, a seed layer, a leakage barrier layer, and an interface control layer.

[0366] In the following, the reference to Fig.21A In the embodiments of FIG. 21B to FIG. 21F A detailed description of the constituent elements.

[0367] Reference Fig.21B, the capacitor 612 may include a cylindrical bottom electrode 601, a multilayer stack 600D and a top electrode 602. The capacitor 612 may further include a support 600S. The support 600S may be a structure that supports the outer wall of the bottom electrode 601. The support 600S may be or include silicon nitride. According to another embodiment of the present invention, a multilayer support including a plurality of supports 600S may support the bottom electrode 601. For example, the multilayer support may be a two-layer support structure including a lower support and an upper support. Moreover, the multilayer support may be a three-layer support structure including a lower support, a middle support and an upper support.

[0368] Reference Fig. 21C and Fig.21D , capacitors 613 and 614 may include a pillar-shaped bottom electrode 601P, a multilayer stack 600D, a heat source layer 603 , and a top electrode 602 . Fig.21D The capacitor 614 may also include a support 600S.

[0369] Reference Fig.21E and Fig.21F , capacitors 615 and 616 may include a pylinder-shaped bottom electrode 601L, a multilayer stack 600D, a heat source layer 603 and a top electrode 602 . Fig.21F The capacitor 616 may further include a support 600S. The bottom electrode 601L may have a composite structure in which a columnar shape and a cylindrical shape are combined. Therefore, the composite structure of the columnar shape and the cylindrical shape may be referred to as a columnar-cylindrical shape.

[0370] According to another embodiment of the present invention, FIG. 21A to FIG. 21F In the embodiment, an additional reinforcement layer may be pre-formed before forming the cylindrical bottom electrode 601, the pillar-shaped bottom electrode 601P or the pillar-shaped bottom electrode 601L.

[0371] FIG. 22A to FIG. 22D is a cross-sectional view illustrating a method for forming a capacitor according to another embodiment of the present invention. FIG. 22A to FIG. 22D Shown according to Fig.21A An example of a modified example of a method for manufacturing a capacitor.

[0372] Reference Fig.22A After forming the mold layer 611M, the capacitor opening 611C may be formed by etching the mold layer 611M. The mold layer 611M may be or include silicon oxide.

[0373] An additional reinforcement layer KBL' may be conformally formed over the bottom and sidewalls of the capacitor opening 611C. The additional reinforcement layer KBL' may be formed of the same material as that of the reinforcement layer of the above-described embodiment.

[0374] Reference Fig. 22B , a cylindrical bottom electrode 601 may be formed above the additional enhancement layer KBL′.

[0375] Reference Fig. 22C , the mold layer 611M may be removed by a dip-out process. The additional reinforcement layer KBL' may remain unremoved.

[0376] Reference Fig.22D , a multilayer stack 600D may be formed over the bottom electrode 601 and the additional reinforcement layer KBL'. The multilayer stack 600D may include the reinforcement layer KBL and the dielectric layer stack DE. The dielectric layer stack DE may be a hafnium oxide-based material and may further include a leakage barrier layer and an interface control layer. The dielectric layer stack DE may further include a plurality of reinforcement layers.

[0377] A heat source layer 603 may be formed over the multilayer stack 600D. A top electrode 602 may be formed over the heat source layer 603.

[0378] As described above, a capacitor having a high dielectric constant and a low leakage current can be obtained by forming a multilayer stack 600D to include a reinforcement layer, a hafnium oxide-based dielectric layer, and a leakage barrier layer and forming a heat source layer 603 over the multilayer stack 600D. As a result, a highly integrated DRAM memory cell with improved refresh characteristics and reliability can be manufactured.

[0379] The dielectric layer stack according to the above embodiment of the present invention can be applied to the peripheral circuit of DRAM. For example, DRAM may include: a memory cell region ( Fig. 20A 500) and a peripheral circuit region including a peripheral transistor. At least one of the capacitor 600 and the peripheral transistor of the memory cell 500 may include one of the multilayer stacks of the above-mentioned embodiments of the present invention. For example, a hafnium oxide-based dielectric layer and a leakage barrier layer may be included, and the hafnium oxide-based dielectric layer may include a tetragonal hafnium oxide layer, a tetragonal seed layer, and a doping layer.

[0380] The dielectric layer stack according to the above-mentioned embodiment of the present invention can be applied to a metal-insulator-metal (MIM) capacitor. For example, the MIM capacitor can be or include a first metal electrode, a second metal electrode, a hafnium oxide-based dielectric layer, and a leakage barrier layer formed between the first metal electrode and the second metal electrode, wherein the hafnium oxide-based dielectric layer includes a tetragonal hafnium oxide layer, a tetragonal seed layer, and a doping layer.

[0381] The dielectric layer stack according to the above-mentioned embodiment of the present invention can be applied to embedded DRAM. For example, the embedded DRAM may include a logic circuit and the embedded DRAM, and the capacitor of the embedded DRAM may include a hafnium oxide-based dielectric layer and a leakage barrier layer, wherein the hafnium oxide-based dielectric layer may include a tetragonal hafnium oxide layer, a tetragonal seed layer, and a doping layer.

[0382] The dielectric layer stack according to the above-described embodiment of the present invention can be applied to a three-dimensional (3D) NAND. For example, a 3D NAND may include a columnar channel layer, a word line surrounding the columnar channel layer, and a leakage barrier layer and a hafnium oxide-based dielectric layer between the columnar channel layer and the word line, wherein the hafnium oxide-based dielectric layer may include a tetragonal hafnium oxide layer, a tetragonal seed layer, and a doping layer.

[0383] According to the embodiment of the present invention, tetragonal hafnium oxide can be easily formed at a low temperature by using a seed layer and a heat source layer.

[0384] According to an embodiment of the present invention, the capacitance of a capacitor may be increased due to tetragonal hafnium oxide having a high dielectric constant and a low leakage current.

[0385] According to an embodiment of the present invention, as the enhancement layer increases the dielectric constant of the hafnium oxide layer, the capacitance of the capacitor may be further increased.

[0386] While the present invention has been described with respect to the specific embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims.

Claims

1. A semiconductor device, comprising: a first electrode; a second electrode; and a multilayer stack disposed between the first electrode and the second electrode and including a hafnium oxide layer having a tetragonal crystal structure, Wherein, the multi-layer stack comprises: a seed layer for promoting tetragonal crystallization of the hafnium oxide layer and having a tetragonal crystal structure; and An enhancement layer, used to increase the dielectric constant of the hafnium oxide layer; Wherein, the seed layer having the doping layer embedded therein comprises: The doping layer has a thickness that does not separate the grains of the seed layer.

2. The semiconductor device according to claim 1, wherein The enhancement layer is formed under the hafnium oxide layer, and the enhancement layer and the hafnium oxide layer are in direct contact with each other.

3. The semiconductor device according to claim 1, wherein The hafnium oxide layer has a dielectric constant of 70 to 150.

4. The semiconductor device according to claim 1, wherein: The reinforcement layer has a thickness thinner than that of the hafnium oxide layer.

5. The semiconductor device according to claim 1, wherein: The reinforcing layer has a thickness of 0.1 to Thickness.

6. The semiconductor device according to claim 1, wherein The reinforcement layer includes a metal oxide having an oxygen content of 1 to 50 atomic %.

7. The semiconductor device according to claim 1, wherein The enhancement layer includes a metal oxynitride having an oxygen content higher than a nitrogen content.

8. The semiconductor device according to claim 1, wherein The reinforcement layer includes a divalent metal, a trivalent metal, or a pentavalent metal.

9. The semiconductor device according to claim 1, wherein: The enhancement layer includes at least one of niobium, tantalum and vanadium.

10. The semiconductor device according to claim 1, wherein The enhancement layer includes niobium oxide, niobium oxynitride, tantalum oxide, tantalum oxynitride, vanadium oxide or vanadium oxynitride.

11. The semiconductor device according to claim 1, wherein The enhancement layer and the seed layer include different materials.

12. The semiconductor device according to claim 1, wherein The dielectric constant of the seed layer is lower than the dielectric constant of the hafnium oxide layer.

13. The semiconductor device according to claim 1, wherein The seed layer having the doping layer embedded therein comprises: Tetragonal seed crystal lower layer; and The upper layer of tetragonal seed crystals, and A doping layer disposed between the lower layer of tetragonal seed crystals and the upper layer of tetragonal seed crystals, The doping layer has a thickness that does not separate the grains of the lower layer of the tetragonal seed crystal from the grains of the upper layer of the tetragonal seed crystal.

14. The semiconductor device according to claim 13, wherein: The tetragonal seed lower layer and the tetragonal seed upper layer are thicker than the doping layer, and the tetragonal seed upper layer is thicker than the tetragonal seed lower layer.

15. The semiconductor device according to claim 13, wherein: The doped layer includes doped tetragonal zirconia doped with a dopant, and the tetragonal seed crystal lower layer and the tetragonal seed crystal upper layer include undoped tetragonal zirconia not doped with any dopant, and The dopant includes aluminum or beryllium.

16. The semiconductor device according to claim 1, wherein The energy band gap of the doping layer is higher than the energy band gaps of the hafnium oxide layer and the seed layer.

17. The semiconductor device according to claim 1, wherein The hafnium oxide layer also includes a crystallization-promoting dopant.

18. The semiconductor device according to claim 17, wherein: The crystallization-promoting dopant includes strontium (Sr), lanthanum (La), gadolinium (Gd), aluminum (Al), silicon (Si), yttrium (Y), zirconium (Zr), niobium (Nb), bismuth (Bi), germanium (Ge), dysprosium (Dy), titanium (Ti), cerium (Ce), magnesium (Mg), nitrogen (N) or a combination thereof.

19. The semiconductor device according to claim 1, wherein The multilayer stack comprises: a plurality of the hafnium oxide layers, a plurality of the enhancement layers and a plurality of the seed layers, wherein the multilayer stack comprises a direct contact interface wherein each hafnium oxide layer is in direct contact with each reinforcement layer, Each enhancement layer is disposed below each hafnium oxide layer.

20. The semiconductor device according to claim 1, further comprising: A heat source layer is between the multilayer stack and the second electrode.

21. The semiconductor device according to claim 20, wherein: The heat source layer includes a conductive material.

22. The semiconductor device according to claim 1, wherein The multi-layer stack further comprises: Leakage barriers; and an interface control layer above the leakage barrier layer, and The leakage blocking layer and the interface control layer are located at higher positions than the hafnium oxide layer and the seed layer.

23. The semiconductor device according to claim 22, wherein: The leakage blocking layer includes a material having a lower dielectric constant and a higher band gap than the hafnium oxide layer and the seed layer.

24. The semiconductor device according to claim 22, wherein: The leakage barrier layer includes an aluminum-containing material or a beryllium-containing material.

25. The semiconductor device according to claim 22, wherein: The leakage blocking layer has a thickness thinner than the hafnium oxide layer and the seed layer.

26. The semiconductor device according to claim 22, wherein: The interface control layer includes a material having a higher electronegativity than the hafnium oxide layer.

27. The semiconductor device according to claim 22, wherein: The interface control layer includes titanium oxide, tantalum oxide, niobium oxide, aluminum oxide, silicon oxide, tin oxide, germanium oxide, molybdenum dioxide, molybdenum trioxide, iridium oxide, ruthenium oxide, nickel oxide or a combination thereof.

28. The semiconductor device according to claim 1, wherein The multi-layer stack includes a sequential stack of the enhancement layer, the hafnium oxide layer, and the seed layer.

29. The semiconductor device according to claim 1, wherein: The multi-layer stack includes a sequential stack of a first reinforcement layer, a first hafnium oxide layer, the seed layer, a second reinforcement layer, and a second hafnium oxide layer.

30. A method for manufacturing a semiconductor device, comprising: forming a multilayer stack over the first electrode, the multilayer stack comprising an enhancement layer, a seed layer having a doping layer embedded therein, and an initial hafnium oxide layer; forming a heat source layer over the multilayer stack to crystallize the initial hafnium oxide layer into tetragonal hafnium oxide; as well as forming a second electrode above the heat source layer; Wherein, the seed layer having the doping layer embedded therein comprises: The doping layer has a thickness that does not separate the grains of the seed layer.

31. The method according to claim 30, wherein: The forming of the multi-layer stack comprises: forming the reinforcement layer; forming the seed layer by embedding the doping layer over the enhancement layer; and The initial hafnium oxide layer is formed over the seed layer.

32. The method of claim 30, wherein: The forming of the multi-layer stack comprises: forming the reinforcement layer; forming the initial hafnium oxide layer over the enhancement layer; and The seed layer is formed by embedding the doping layer over the initial hafnium oxide layer.

33. The method of claim 30, wherein: The multilayer stack comprises at least one direct contact interface, and The direct contact interface includes a direct contact interface that directly contacts the initial hafnium oxide layer and the enhancement layer.

34. The method of claim 30, wherein: The forming of the multilayer stack comprises: forming a single seed layer having the doping layer embedded in the seed layer between the two initial hafnium oxide layers, and The enhancement layer is pre-formed to contact each of the initial hafnium oxide layers.

35. The method of claim 30, wherein: The seed layer includes tetragonal zirconia, and The doping layer includes aluminum or beryllium embedded in the tetragonal zirconia.

36. The method of claim 30, wherein: The formation of the multilayer stack is performed by an atomic layer deposition (ALD) process.

37. The method of claim 30, wherein: The forming of the heat source layer over the multilayer stack is performed at a temperature of 300 to 500°C.

38. The method of claim 30, wherein: The enhancement layer includes at least one of niobium, tantalum, and vanadium.

39. The method of claim 30, wherein: The enhancement layer includes niobium oxide, niobium oxynitride, tantalum oxide, tantalum oxynitride, vanadium oxide or vanadium oxynitride.

40. The method of claim 30, wherein: The forming of the multi-layer stack further comprises: forming a leakage blocking layer at a higher level than the enhancement layer, the seed layer having the doping layer embedded therein, and the initial hafnium oxide layer; and An interface control layer is formed over the leakage barrier layer.

41. The method of claim 40, wherein: The leakage blocking layer includes a material having a lower dielectric constant and a higher band gap than the tetragonal hafnium oxide layer and the seed layer.

42. The method of claim 40, wherein: The leakage barrier layer includes an aluminum-containing material or a beryllium-containing material.

43. The method of claim 40, wherein: The interface control layer includes a material having a higher electronegativity than the hafnium oxide layer and the seed layer.

44. The method of claim 40, wherein: The interface control layer includes titanium oxide, tantalum oxide, niobium oxide, aluminum oxide, silicon oxide, tin oxide, germanium oxide, molybdenum dioxide, molybdenum trioxide, iridium oxide, ruthenium oxide, nickel oxide or a combination thereof.

45. The method of claim 30, wherein: The enhancement layer is formed under the hafnium oxide layer, and the enhancement layer and the hafnium oxide layer are in direct contact with each other.

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