Tetrahedrally structured compound doped sb-te phase change material, phase change memory

Abstract

The application provides a tetrahedral structure compound doped Sb-Te phase change material and a phase change memory, and belongs to the technical field of micro-nano electronics. x (Sb-Te) 1‑x , MA is a tetrahedral structure compound, x represents the percentage of the number of molecules of the tetrahedral structure compound in the total number of molecules, 0

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of micro-nano electronic technology, and more particularly relates to a stable tetrahedral structure compound doped Sb-Te phase change material and phase change memory. BACKGROUND

[0002] In today's era of rapid development of electronic technology and information industry, with the explosive growth of data, people's demand for non-volatile memory is also increasing. Phase change memory (PCM) is considered by the International Semiconductor Industry Association as the most likely to replace flash memory and dynamic storage and become the mainstream storage of the future due to its high integration, fast response speed, long cycle life and low power consumption.

[0003] The basic principle of the phase change memory cell is to use an electric pulse signal to act on the device cell, so that the phase change material undergoes reversible phase change between amorphous state and polycrystalline state to realize the storage of "0" and "1". A narrow pulse width and high amplitude electric pulse is applied to the cell to perform RESET operation, and the crystalline phase change storage material melts and quickly cools to become amorphous disordered state, thereby realizing the fast resistance change from low resistance state "0" to high resistance state "1". Conversely, a wide pulse width and low amplitude electric pulse is applied to the phase change cell to perform SET operation, and the amorphous phase change storage material undergoes a kind of annealing process to crystallize and return to the low resistance state, realizing the erasing of "1" to "0".

[0004] The phase change material is mainly a chalcogenide compound material, among which the compound composed of Ge, Sb and Te is the most common. Sb-Te system is a phase change material that has attracted widespread attention in recent years, which has low crystallization temperature and growth dominant crystallization process, and fast crystallization speed. Therefore, the phase change memory device based on Sb-Te system has the characteristics of fast SET speed. However, the amorphous stability of the device needs to be further improved.

[0005] Optimization of the performance of the phase change material is the key to improving the performance of the phase change memory, and the microstructure of the phase change material determines its macroscopic characteristics. At present, the main optimization method to improve the stability of the Sb-Te system phase change material is to introduce a tetrahedral structure by doping, such as doping of the fourth main group element. In the amorphous state, the strong-bonded tetrahedral cluster is quite different from the structure of Sb-Te crystal (octahedron), which hinders the spontaneous crystallization of the phase change material, thereby improving the amorphous stability and data retention capability. However, the incorporation of the above single element generally combines with a certain element in the base phase change material to form a bond, changes the original composition of the phase change material and destroys the crystal lattice structure of the phase change material, which sacrifices the crystallization speed to some extent while improving the stability of the device, and it is difficult to comprehensively improve the performance of the device.

[0006] Therefore, there is a need to develop a new method and product for a modified Sb-Te material system to achieve precise, sensitive, and simple control of its microstructure, so that it can be used as a commercial phase change memory material. SUMMARY OF THE INVENTION

[0007] Aiming at the defects of the prior art, the purpose of the present invention is to provide an Sb-Te phase change material doped with a stable tetrahedral structure compound and a phase change memory. By doping with a stable tetrahedral structure compound, tetrahedral clusters with a large difference from the octahedral crystal structure are formed in the phase change layer of the Sb-Te system, hindering the spontaneous crystallization of the Sb-Te system phase change material, thereby improving its amorphous stability and data retention ability. It does not bond with the elements in the Sb-Te system phase change material, ensuring the integrity of the lattice structure of the Sb-Te system phase change material, and can also reduce the grain size and prevent the atomic migration of the phase change elements, ultimately comprehensively improving the comprehensive performance of the device.

[0008] To achieve the above purpose, according to one aspect of the present invention, there is also provided an Sb-Te phase change material doped with a tetrahedral structure compound, with the chemical formula MA x (Sb-Te) 1-x , where MA is a tetrahedral structure compound, x represents the percentage of the number of tetrahedral structure compound molecules in the total number of molecules, 0 < x < 10%, and the tetrahedral structure compound is selected from one or more of SiC, SiN, GeC, GeN, BN, GaN, etc.

[0009] Furthermore, the tetrahedral structure compound MA is stable in the phase change layer of the Sb-Te system, and its structure is completely different from the octahedral crystal structure of the Sb-Te system, thereby hindering the spontaneous crystallization of the Sb-Te system phase change material, and improving its amorphous stability and data retention ability.

[0010] Furthermore, the elements of the tetrahedral structure compound MA are independent of the elements in the Sb-Te system phase change material and there is no bonding, no substitution or interstitial doping phenomenon, thereby ensuring the integrity of the lattice structure of the Sb-Te system phase change material to maintain the performance of rapid crystallization.

[0011] Furthermore, there are only the following several chemical bonds, including M-A bonds, M-M bonds, A-A bonds, and Sb-Te bonds.

[0012] Furthermore, the tetrahedral structure compound MA is uniformly distributed in the grain boundaries of the crystalline phase change material in an amorphous form to reduce the grain size, hinder the atomic migration of the phase change elements, and ultimately improve the reliability of the device.

[0013] Furthermore, it is prepared by magnetron sputtering, chemical vapor deposition, atomic layer deposition, electroplating or electron beam evaporation.

[0014] Furthermore, the Sb-Te system phase change materials include SbTe, Sb2Te1, Sb2Te3, and Sb4Te1.

[0015] Furthermore, it was obtained by co-sputtering with an Sb-Te system target and an MA target.

[0016] According to a second aspect of the present invention, a phase change memory based on an Sb-Te system phase change material is also provided, comprising a bottom electrode, an isolation layer, a phase change memory material thin film layer, and a top electrode stacked sequentially, wherein the phase change memory material thin film layer is an Sb-Te phase change material doped with a tetrahedral structure compound as described above.

[0017] In summary, the technical solutions conceived by this invention have the following beneficial effects compared with the prior art:

[0018] In the phase change material based on stable tetrahedral compound doping of the present invention, the stable tetrahedral compound MA forms a stable tetrahedral structure in the Sb-Te system phase change layer. This tetrahedral structure differs significantly from the octahedral crystal structure of the Sb-Te system, hindering the spontaneous crystallization of the Sb-Te system phase change material, thereby improving its amorphous stability and data retention capability. Furthermore, the stable tetrahedral compound MA has high chemical bond energy, and in thin film materials, it hardly bonds with elements in the Sb-Te system, forming only MA, MM, and AA bonds. No substitutional or interstitial doping occurs, ensuring the integrity of the Sb-Te system phase change material's lattice structure and thus not affecting its rapid crystallization performance. In addition, the stable tetrahedral compound MA readily and uniformly distributes in an amorphous form at the grain boundaries of the crystalline phase change material, reducing grain size, hindering atomic migration of phase change elements, improving device reliability, and ultimately comprehensively improving the overall performance of the device. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of Sb-Te phase change material doped with a tetrahedral compound.

[0020] Figure 2 This is a flowchart of the fabrication process of a phase change memory based on a stable face-centered cubic compound-doped Sb-Te system phase change material, as provided in Embodiment 2 of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0022] The present invention relates to an information storage device, particularly to a novel high thermal stability Sb-Te system phase change material doped with a stable tetrahedral structure compound and a phase change memory. By adopting a doping process of the stable tetrahedral structure compound, the organization of the compound is used to regulate the Sb-Te system phase change material. Through doping with the stable tetrahedral structure compound, stable tetrahedral clusters with a large difference from the octahedral crystal structure of the Sb-Te system are formed in the Sb-Te system phase change layer, hindering the spontaneous crystallization of the Sb-Te system phase change material, thereby improving its amorphous stability and data retention ability. The elements in the stable tetrahedral structure compound hardly bond with the elements in the Sb-Te system phase change material, so there is no substitution or interstitial doping, ensuring the integrity of the lattice structure of the Sb-Te system phase change material, and thus not affecting its performance characteristics of rapid crystallization. In addition, the stable tetrahedral structure compound is easily and uniformly distributed in the grain boundaries of the crystalline Sb-Te system phase change material in an amorphous form, reducing the grain size, preventing the atomic migration of the phase change elements, improving the reliability of the device, and ultimately comprehensively improving the comprehensive performance of the device.

[0023] Figure 1 FIG. is a schematic structural diagram of the Sb-Te phase change material doped with the tetrahedral structure compound. As can be seen from the figure, the doped tetrahedral structure compound stably exists in the matrix material, and the stable tetrahedral structure with a large difference from the octahedral crystal structure of the Sb-Te system can hinder the spontaneous crystallization of the Sb-Te system phase change material, thereby improving its amorphous stability and data retention ability. The phase change material obtained by introducing the stable tetrahedral structure compound MA into the Sb-Te system phase change material in the present invention has a chemical composition general formula of MA x (Sb-Te) 1-x , where MA is a stable tetrahedral structure compound, and x represents the percentage of the number of high melting point compound molecules in the total number of molecules. The preferred value range of x is 0 < x < 10%, and further preferably x = 5%. By adjusting the sputtering power of MA during preparation, the value of x can be regulated. Preferably, MA x (Sb-Te) 1-x The thickness of the phase change thin film material is 50 nm to 300 nm.

[0024] In one embodiment of the present invention, the phase change memory cell sequentially includes a bottom electrode, an isolation layer, a phase change material thin film layer, and a top electrode. The material of the phase change material thin film layer is the Sb-Te system phase change material doped with the stable tetrahedral structure compound as described above, which is filled in a small hole with a diameter of 250 nm and a depth of 100 nm. The material of the bottom electrode is TiN, the material of the isolation layer is SiO2, and the material of the top electrode is metal Pt.

[0025] This invention provides a stable tetrahedral compound-doped Sb-Te phase change material for phase change memory, which includes methods such as magnetron sputtering, chemical vapor deposition, atomic layer deposition, electroplating, and electron beam evaporation. Among these methods, magnetron sputtering is the most flexible, allowing for co-sputtering with an Sb-Te target and a MA target. This method can prepare the stable tetrahedral compound-doped Sb-Te phase change material according to the general chemical formula.

[0026] The stable tetrahedral compound-doped Sb-Te phase change memory material and device fabrication process of this invention are mature and easily compatible with existing microelectronic process technologies.

[0027] To illustrate the method of the present invention in more detail, the following detailed description is provided in conjunction with more specific embodiments.

[0028] Example 1

[0029] The stable tetrahedral compound-doped Sb-Te phase change thin film material prepared in this embodiment for phase change memory devices has the general chemical formula MA. x (ST) 1-x Where MA represents SiN, ST represents Sb2Te3, and in this embodiment x = 0.05.

[0030] The SiN-Sb₂Te₃ phase change memory thin film material was prepared by magnetron sputtering. High-purity argon gas was used as the sputtering gas at a pressure of 0.5 Pa. An AC power supply of 40 W was used for the SiN target, and an AC power supply of 60 W was used for the Sb₂Te₃ target. The specific preparation process includes the following steps:

[0031] 1. Select a SiO2 / Si(100) substrate with a size of 1cm×1cm, clean the surface and back side to remove dust particles, organic and inorganic impurities.

[0032] a) Place the SiO2 / Si(100) substrate in an acetone solution and vibrate it with an ultrasonic power of 40W for 10 minutes, then rinse it with deionized water.

[0033] b) The acetone-treated substrate was ultrasonically vibrated in an ethanol solution at 40W power for 10 minutes, rinsed with deionized water, and dried with high-purity N2 gas on the surface and back side to obtain the substrate to be sputtered.

[0034] 2. SiN-Sb2Te3 phase change memory thin film material was prepared by co-sputtering with DC and AC power.

[0035] The SiN and Sb₂Te₃ targets, both with a purity of 99.99% (atomic percentage), were placed and their base vacuum was evacuated to 10.-5 Pa.

[0036] High-purity Ar gas was used as the sputtering gas, and the sputtering pressure was adjusted to 0.5 Pa. The distance between the target and the substrate was 120 mm.

[0037] The AC power supply for the SiN target was set to 40W, and the AC power supply for the Sb2Te3 target was set to 60W.

[0038] Pre-sputtering of SiN and Sb2Te3 targets for 10 minutes was performed to clean the target surfaces.

[0039] After pre-sputtering, the baffle was turned on, and the sputtering time was 8 minutes. The thickness of the prepared film was about 100 nm.

[0040] Example 2

[0041] In this embodiment, SiN-doped Sb₂Te₃ phase change thin film material is used as the phase change layer material to fabricate the memory device. The SiN-doped Sb₂Te₃ phase change layer is prepared by magnetron sputtering. High-purity argon gas is used as the sputtering gas at a pressure of 0.5 Pa. An AC power supply with a power of 40 W is used for the SiN target, and an AC power supply with a power of 60 W is used for the Sb₂Te₃ target. Figure 2 This is a flowchart of the fabrication process of a phase change memory based on a stable face-centered cubic compound-doped Sb-Te system phase change material, as provided in Embodiment 2 of the present invention. As shown in the figure, the specific fabrication process includes the following steps:

[0042] 1. Select a SiO2 / Si(100) substrate with a size of 1cm×1cm, clean the surface and back side to remove dust particles, organic and inorganic impurities.

[0043] a) Place the SiO2 / Si(100) substrate in an acetone solution and vibrate it with an ultrasonic power of 40W for 10 minutes, then rinse it with deionized water.

[0044] b) The acetone-treated substrate was ultrasonically vibrated in an ethanol solution at 40W power for 10 minutes, rinsed with deionized water, and dried with high-purity N2 gas on the surface and back side to obtain the substrate to be sputtered.

[0045] 2. A 100 nm TiN bottom electrode was prepared by DC power supply sputtering.

[0046] 3. A 100 nm SiO2 insulating layer was deposited on the TiN bottom electrode using chemical vapor deposition.

[0047] 4. Through-holes with a depth of 100 nm and a diameter of 250 nm are formed in the SiO2 insulating layer by processes such as electron beam lithography etching.

[0048] 5. The memory array is formed using photolithography.

[0049] 6. Filling the vias with SiN-Sb2Te3 phase change memory thin film material using AC power sputtering.

[0050] The SiN and Sb₂Te₃ targets, both with a purity of 99.99% (atomic percentage), were placed and their base vacuum was evacuated to 10. -5 Pa.

[0051] High-purity Ar gas was used as the sputtering gas, and the sputtering pressure was adjusted to 0.5 Pa. The distance between the target and the substrate was 120 mm.

[0052] The AC power supply for the SiN target was set to 80W, and the AC power supply for the Sb2Te3 target was set to 60W.

[0053] Pre-sputtering of SiN and Sb2Te3 targets for 10 minutes was performed to clean the target surfaces.

[0054] After pre-sputtering, the baffle was turned on, and the sputtering time was 8 minutes. The thickness of the prepared phase change layer was about 100 nm.

[0055] 7. A 100 nm Pt top electrode was fabricated using a DC power supply sputtering method to obtain a complete phase change memory device array based on the SiN-Sb2Te3 system phase change layer.

[0056] Example 3

[0057] The stable tetrahedral compound-doped Sb-Te phase change thin film material prepared in this embodiment for phase change memory devices has the general chemical formula MA. x (ST) 1-x Where MA represents GeC, ST represents Sb2Te3, and in this embodiment x = 0.04.

[0058] GeC-Sb₂Te₃ phase change memory thin film materials were prepared by magnetron sputtering. High-purity argon gas was used as the sputtering gas at a pressure of 0.5 Pa. An AC power supply of 30 W was used for the GeC target, and an AC power supply of 60 W was used for the Sb₂Te₃ target. The specific preparation process includes the following steps:

[0059] 1. Select a SiO2 / Si(100) substrate with a size of 1cm×1cm, clean the surface and back side to remove dust particles, organic and inorganic impurities.

[0060] a) Place the SiO2 / Si(100) substrate in an acetone solution and vibrate it with an ultrasonic power of 40W for 10 minutes, then rinse it with deionized water.

[0061] b) The acetone-treated substrate was ultrasonically vibrated in an ethanol solution at 40W power for 10 minutes, rinsed with deionized water, and dried with high-purity N2 gas on the surface and back side to obtain the substrate to be sputtered.

[0062] 2. GeC-Sb2Te3 phase change memory thin film material was prepared by co-sputtering with DC and AC power.

[0063] a) Place the GeC and Sb2Te3 targets, both with a purity of 99.99% (atomic percentage), and evacuate their background vacuum to 10. -5 Pa.

[0064] b) Use high-purity Ar gas as the sputtering gas, adjust the sputtering pressure to 0.5 Pa, and the distance between the target and the substrate is 120 mm.

[0065] c) Set the AC power supply for GeC target material to 30W and the AC power supply for Sb2Te3 target material to 60W.

[0066] d) Perform 10 minutes of pre-sputtering on GeC and Sb2Te3 targets to clean the target surfaces.

[0067] e) After pre-sputtering is completed, the baffle is turned on. When the sputtering time is 8 minutes, the thickness of the prepared film is about 100 nm.

[0068] Example 4

[0069] In this embodiment, GeC-doped Sb₂Te₃ phase change thin film material is used as the phase change layer material to fabricate the memory device. The GeC-doped Sb₂Te₃ phase change layer is prepared by magnetron sputtering. High-purity argon gas is used as the sputtering gas at a pressure of 0.5 Pa. An AC power supply with a power of 30 W is used for the GeC target, and an AC power supply with a power of 60 W is used for the Sb₂Te₃ target. The specific fabrication process includes the following steps:

[0070] 1. Select a SiO2 / Si(100) substrate with a size of 1cm×1cm, clean the surface and back side to remove dust particles, organic and inorganic impurities.

[0071] a) Place the SiO2 / Si(100) substrate in an acetone solution and vibrate it with an ultrasonic power of 40W for 10 minutes, then rinse it with deionized water.

[0072] b) The acetone-treated substrate was ultrasonically vibrated in an ethanol solution at 40W power for 10 minutes, rinsed with deionized water, and dried with high-purity N2 gas on the surface and back side to obtain the substrate to be sputtered.

[0073] 2. A 100 nm TiN bottom electrode was prepared by DC power supply sputtering.

[0074] 3. A 100 nm SiO2 insulating layer was deposited on the TiN bottom electrode using chemical vapor deposition.

[0075] 4. Through-holes with a depth of 100 nm and a diameter of 250 nm are formed in the SiO2 insulating layer by processes such as electron beam lithography etching.

[0076] 5. The memory array is formed using photolithography.

[0077] 6. Using AC power sputtering, GeC-Sb2Te3 phase change memory thin film material is filled into the through-holes.

[0078] a) Place the GeC and Sb2Te3 targets, both with a purity of 99.99% (atomic percentage), and evacuate their background vacuum to 10. -5 Pa.

[0079] b) Use high-purity Ar gas as the sputtering gas, adjust the sputtering pressure to 0.5 Pa, and the distance between the target and the substrate is 120 mm.

[0080] c) Set the AC power supply for GeC target material to 30W and the AC power supply for Sb2Te3 target material to 60W.

[0081] d) Perform 10 minutes of pre-sputtering on GeC and Sb2Te3 targets to clean the target surfaces.

[0082] e) After pre-sputtering is completed, the baffle is turned on and the sputtering time is 8 minutes. The thickness of the prepared phase change layer is about 100 nm.

[0083] 7. A 100 nm Pt top electrode was fabricated using a DC power supply sputtering method to obtain a complete phase change memory device array based on the GeC-Sb2Te3 system phase change layer.

[0084] Example 5

[0085] The stable tetrahedral compound-doped Sb-Te phase change thin film material prepared in this embodiment for phase change memory devices has the general chemical formula MA. x (ST) 1-x Where MA represents GaN, ST represents Sb4Te1, and in this embodiment x = 0.04.

[0086] GaN-Sb4Te1 phase change memory thin film materials were prepared by magnetron sputtering. High-purity argon gas was used as the sputtering gas at a pressure of 0.5 Pa. The GaN target was powered by an AC power supply of 32 W, and the Sb4Te1 target by an AC power supply of 60 W. The specific preparation process includes the following steps:

[0087] 1. Select a SiO2 / Si(100) substrate with a size of 1cm×1cm, clean the surface and back side to remove dust particles, organic and inorganic impurities.

[0088] a) Place the SiO2 / Si(100) substrate in an acetone solution and vibrate it with an ultrasonic power of 40W for 10 minutes, then rinse it with deionized water.

[0089] b) The acetone-treated substrate was ultrasonically vibrated in an ethanol solution at 40W power for 10 minutes, rinsed with deionized water, and dried with high-purity N2 gas on the surface and back side to obtain the substrate to be sputtered.

[0090] 2. GaN-Sb4Te1 phase change memory thin film material was prepared by co-sputtering with DC and AC power.

[0091] a) Place the GaN and Sb4Te1 targets, both with a purity of 99.99% (atomic percentage), and evacuate their base vacuum to 10. -5 Pa.

[0092] b) Use high-purity Ar gas as the sputtering gas, adjust the sputtering pressure to 0.5 Pa, and the distance between the target and the substrate is 120 mm.

[0093] c) Set the AC power supply for GaN target material to 32W and the AC power supply for Sb4Te1 target material to 60W.

[0094] d) Perform 10 minutes of pre-sputtering on GaN and Sb4Te1 targets to clean the target surfaces.

[0095] e) After pre-sputtering is completed, the baffle is turned on. When the sputtering time is 8 minutes, the thickness of the prepared film is about 100 nm.

[0096] Example 6

[0097] In this embodiment, GaN-doped Sb4Te1 phase change thin film material is used as the phase change layer material to fabricate the memory device. The GaN-doped Sb4Te1 phase change layer is prepared by magnetron sputtering. High-purity argon gas is used as the sputtering gas at a pressure of 0.5 Pa. An AC power supply with a power of 32 W is used for the GaN target, and an AC power supply with a power of 60 W is used for the Sb4Te1 target. The specific fabrication process includes the following steps:

[0098] 1. Select a SiO2 / Si(100) substrate with a size of 1cm×1cm, clean the surface and back side to remove dust particles, organic and inorganic impurities.

[0099] a) Place the SiO2 / Si(100) substrate in an acetone solution and vibrate it with an ultrasonic power of 40W for 10 minutes, then rinse it with deionized water.

[0100] b) The acetone-treated substrate was ultrasonically vibrated in an ethanol solution at 40W power for 10 minutes, rinsed with deionized water, and dried with high-purity N2 gas on the surface and back side to obtain the substrate to be sputtered.

[0101] 2. A 100 nm TiN bottom electrode was prepared by DC power supply sputtering.

[0102] 3. A 100 nm SiO2 insulating layer was deposited on the TiN bottom electrode using chemical vapor deposition.

[0103] 4. Through-holes with a depth of 100 nm and a diameter of 250 nm are formed in the SiO2 insulating layer by processes such as electron beam lithography etching.

[0104] 5. The memory array is formed using photolithography.

[0105] 6. Using AC power sputtering, GeC-Sb2Te3 phase change memory thin film material is filled into the through-holes.

[0106] a) Place the GaN and Sb4Te1 targets, both with a purity of 99.99% (atomic percentage), and evacuate their base vacuum to 10. -5 Pa.

[0107] b) Use high-purity Ar gas as the sputtering gas, adjust the sputtering pressure to 0.5 Pa, and the distance between the target and the substrate is 120 mm.

[0108] c) Set the AC power supply for GaN target material to 32W and the AC power supply for Sb4Te1 target material to 60W.

[0109] d) Perform 10 minutes of pre-sputtering on GaN and Sb4Te1 targets to clean the target surfaces.

[0110] e) After pre-sputtering is completed, the baffle is turned on and the sputtering time is 8 minutes. The thickness of the prepared phase change layer is about 100 nm.

[0111] 7. A 100 nm Pt top electrode was fabricated using a DC power supply sputtering method to obtain a complete phase change memory device array based on the GaN-Sb4Te1 system phase change layer.

[0112] The tetrahedral compound-doped Sb-Te phase change material of the present invention has the chemical formula MA. x (Sb-Te) 1-x MA can also be selected from one or both of SiC and GeN. Sb-Te phase change materials can also be SbTe, Sb2Te1, and Sb4Te1. The range of values ​​for x can be determined based on the structure of the Sb-Te phase change material and the tetrahedral compound. 0 <x<10%。

[0113] In the Sb-Te phase change material based on stable tetrahedral compound doping of the present invention, the stable tetrahedral compound is used to regulate the Sb-Te phase change material, forming stable tetrahedral clusters with a significantly different octahedral crystal structure in the Sb-Te phase change layer. This hinders the spontaneous crystallization of the Sb-Te phase change material, thereby improving its amorphous stability and data retention capability. The elements in the stable tetrahedral compound hardly form bonds with the elements in the Sb-Te phase change material, thus preventing substitutional or interstitial doping and ensuring the integrity of the Sb-Te phase change material's lattice structure, thereby not affecting its rapid crystallization performance. Furthermore, the stable tetrahedral compound is easily distributed in an amorphous form at the grain boundaries of the crystalline Sb-Te phase change material, reducing grain size, preventing atomic migration of phase change elements, improving device reliability, and ultimately comprehensively improving the overall performance of the device.

[0114] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A tetrahedral compound-doped Sb-Te phase change material, characterized in that, Its chemical formula is MA x (Sb-Te) 1-x The Sb-Te system phase change material is selected from SbTe, Sb2Te1, and Sb4Te1, where MA is a tetrahedral compound, x represents the percentage of tetrahedral compound molecules in the total number of molecules, x=4%, and the tetrahedral compound is GeC. The tetrahedral compound MA exhibits structural stability in the Sb-Te phase transition layer. Its structure differs from the octahedral crystal structure of the Sb-Te system, thus hindering the spontaneous crystallization of the Sb-Te phase transition material and thereby improving its amorphous stability and data retention capability. Furthermore, the tetrahedral compound MA element is independent of the elements in the Sb-Te phase change material, without bonding, substitution, or interstitial doping. This ensures the integrity of the Sb-Te phase change material's lattice structure, maintaining its rapid crystallization performance. The tetrahedral compound MA is uniformly distributed in an amorphous form at the grain boundaries of crystalline phase change materials to reduce grain size, hinder atomic migration of phase change elements, and ultimately improve device reliability. It was obtained by co-sputtering an Sb-Te system target and an MA target. Only the following types of chemical bonds exist, including MA bonds, MM bonds, AA bonds, and Sb-Te bonds.

2. A phase change memory based on an Sb-Te system phase change material, characterized in that, It comprises a bottom electrode, an isolation layer, a phase change storage material thin film layer and a top electrode stacked in sequence, wherein the phase change storage material thin film layer is an Sb-Te phase change material doped with a tetrahedral structure compound as described in claim 1.

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