Patent Description:
Spin-transfer torque (STT) magnetic random-access memory (MRAM) is a kind of memory that writes information through spin current and can be used to flip the active elements in magnetic random-access memory. The core of its storage unit is a Magnetic Tunnel Junction (MTJ), which is composed of a magnetic stacked layer structure, a first electrode and a second electrode, wherein the magnetic stacked layer structure includes, stacked from top to bottom, a free layer, a spacer layer and a fixed layer, a second electrode located on top of the free layer, and a first electrode located on the bottom surface of the fixed layer.

However, STT-MRAM is susceptible to interference from external electromagnetic fields. The current chip-level shielding is not enough to completely shield the interference from external electromagnetic fields.

Patent application <CIT> relates to a magnetic shielding of an STT-MRAM cell with one shield, <CIT> relates to an MRAM cell with two magnetic shields surrounding the storage unit and <CIT> relates to a top and bottom shielded MRAM cell, and, therefore, these patent applications provide teachings related to the technical field of the present invention.

According to various embodiments, a semiconductor structure and a manufacturing method thereof are provided to shield interference from external electromagnetic fields.

A method for manufacturing a semiconductor structure according to the present invention includes operations as set forth in claim <NUM>.

In one of the embodiments, the step of forming the first electrode penetrating the first shielding layer includes: forming a first dielectric layer on the first shielding layer; forming a first opening in the first shielding layer and the first dielectric layer.

The first electrode is formed in the first opening.

In one of the embodiments, before the second shielding layer is formed on the top surface and sidewalls of the storage structure, the method further includes: a second dielectric layer on the top surface and sidewalls of the magnetic stacked layer structure is formed, and the first dielectric layer and the second dielectric layer together constitute an isolation layer.

In one of the embodiments, removing the first shielding layer except under the second shielding layer on the sidewall of the magnetic stacked layer structure by using a self-aligned etching process; the first shielding layer and the second shielding layer remaining under the second shielding layer on the sidewall of the magnetic stacked layer structure form the shielding layer.

In one of the embodiments, the bottom surface of the shielding layer is lower than the bottom surface of the magnetic stacked layer structure.

In one of the embodiments, the top of the magnetic stacked layer structure is arc-shaped.

In one of the embodiments, the lateral dimension of the magnetic stacked layer structure is larger than the lateral dimension of the first electrode.

In one of the embodiments, the step of forming a second electrode that penetrates the shielding layer and is electrically connected to the storage structure includes: forming a third dielectric layer on the substrate and the shielding layer; using a planarizing process to remove part of the shielding layer from above the magnetic stacked layer structure to expose the top of the magnetic stacked layer structure; forming a fourth dielectric layer on top of the magnetic stacked layer structure; and forming a second opening in the fourth dielectric layer and the opening exposing the top of the magnetic stacked layer structure.

The second electrode is formed in the second opening.

The present invention also provides a semiconductor structure as set forth in claim <NUM>.

In one of the embodiments, the magnetic stacked layer structure includes a fixed layer, a spacer layer and a free layer.

In one of the embodiments, the materials of the fixed layer and the free layer may be Co, Fe, B, Ta or Ru; the material of the spacer layer includes Mg or O.

In one example, the bottom surface of the second electrode is on the same horizontal plane as the top surface of the magnetic stacked layer structure, the top surface of the shielding layer, and the top surface of the isolation layer.

In summary, a semiconductor structure and a manufacturing method thereof are provided. By forming the first shielding layer first, and then sequentially forming the first electrode, the storage structure, and the second shielding layer, the first shielding layer and the second shielding layer form a shielding layer covering the storage structure. Good shielding of external electromagnetic field interference to the storage structure, ensuring that information can be stored and read and written correctly.

In order to make the above objectives, features and advantages of the present invention more obvious and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In the following description, many specific details are explained in order to fully understand the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the subject matter defined by the claims. Therefore, the present invention is not limited by the specific implementation disclosed below.

Referring to <FIG>, the flowchart provides a method for fabricating a semiconductor structure, the method includes:.

By forming the first shielding layer 200a first, and then sequentially forming the first electrode <NUM>, the storage structure <NUM>, and the second shielding layer 200b, the shielding layer <NUM> composed of the first shielding layer 200a and the second shielding layer 200b constitute the enclosing structure of the storage structure <NUM>. This structure can better shield the storage structure from the interference of the external electromagnetic field, thus it is ensured that the information can be stored, read and written correctly.

To describe the technical features more clearly, the following paragraphs describe each step of the manufacturing process in detail according to the embodiments.

In this embodiment, step S110 provides the substrate <NUM>. The substrate <NUM> can be one of, but not limited to, a silicon substrate, an epitaxially grown silicon substrate, a silicon germanium substrate, a silicon carbide substrate, or a silicon-on-insulator substrate, and another substrate known for carrying semiconductor integrated circuits. The base material of the element can be any. The substrate <NUM> may include device structures such as semiconductor transistors and interconnecting plugs connecting the semiconductor transistors.

Referring to <FIG>, in step S120, a first shielding layer 200a is formed on the substrate <NUM>.

A shielding material is deposed on the substrate <NUM> through a deposition process to form a first shielding layer 200a. In this implementation, the deposition process includes chemical vapor deposition (CVD), physical vapor deposition (PVD), or atomic layer deposition (ALD). The shielding material can be a material with good conductivity, such as silver, copper, gold, etc., which will play a good shielding effect on the electric field; the shielding material may also be a material with good magnetic permeability, such as iron (Fe) , cobalt (Co) and nickel (Ni) alloys, such as cobalt-iron, nickel-iron and nickel-cobalt-iron, or various combinations of NiFe and Co and other alloys with higher magnetic permeability, doped amorphous ferromagnetic alloys. It should be noted that the material with good conductivity can also play a certain shielding effect on the magnetic field, and the material with good magnetic permeability can also play a certain shielding effect on the electric field.

In one of the embodiments, referring to <FIG>, a first dielectric layer 300a is further formed on the first shielding layer 200a. Specifically, a dielectric material such as silicon nitride, silicon oxide, or silicon oxynitride is deposed on the first shielding layer 200a through a deposition process to form the first dielectric layer 300a. The first dielectric layer 300a can be used as a hard mask for patterning the first shielding layer 200a, and can also be used as a part of an isolation layer between the first shielding layer 200a and a subsequently formed storage structure.

Referring to <FIG>, step S130 is performed to form a first electrode <NUM> which penetrates the first shielding layer 200a. Specifically, a first opening (not shown in the figure) is formed in the first shielding layer 200a and the first dielectric layer 300a by applying photolithography and etching processes. The deposited first electrode layer fills the first opening and cover the first dielectric layer 300a. Specifically, the first electrode layer can be formed by physical vapor deposition, chemical vapor deposition, or electroplating. The first electrode layer is a conductive material layer, composing of a metal material layer with good conductivity such as aluminum (Al), tungsten (W), copper (Cu), etc.; the first electrode material deposited on the upper surface of the first dielectric layer 300a is then removed so only a layer in the first opening becomes the first electrode <NUM>. Specifically, the first electrode material disposed covering the upper surface of the first dielectric layer 300a will be e removed either by an etch-back or a chemical mechanical polishing process to form the first electrode <NUM>.

In one of the embodiments, the top surface of the first electrode <NUM> is flush with the top surface of the first dielectric layer 300a. It can be understood that when the top of the first electrode <NUM> is flush with the top of the first dielectric layer 300a, the bottom surface of the first shielding layer 200a is lower than the bottom surface of the subsequently formed storage structure, this arrangement increases the shielding range.

Referring to <FIG>, step S140 is performed to form a storage structure <NUM> on the first electrode <NUM>.

In one of the embodiments, the storage structure <NUM> is a magnetic stacked layer structure. As shown in <FIG>, the magnetic stacked layer structure includes: a first magnetic layer 530a, a spacer material layer 520a, and a second magnetic layer 510a. These layers are sequentially deposited on the substrate <NUM> after the first electrode <NUM> is formed; then, as shown in <FIG>, the first magnetic layer 530a, the spacer material layer 520a, and the second magnetic layer 510a in <FIG> are patterned by photolithography and etching processes to form a magnetic stacked layer structure including a fixed layer <NUM>, a spacer layer <NUM>, and a free layer <NUM>. Specifically, the materials of the first magnetic layer 530a and the second magnetic layer 510a include cobalt (Co), iron (Fe), boron (B), tantalum (Ta) or ruthenium (Ru); the material of the spacer material layer 520a includes magnesium (Mg) or oxygen (O). For example, the fixed layer <NUM> may be CoFeB, the spacer layer <NUM> may be a MgO, and the free layer <NUM> may be CoFeB.

In the invention, the number of the storage structures <NUM> and the number of the first electrodes <NUM> can both be multiples, and the first electrodes <NUM> and the storage structures <NUM> are arranged in a one-to-one correspondence; and the first electrodes <NUM> are distributed on the substrate <NUM> at intervals. The storage structures <NUM> have spaces between any two of them.

In one of the embodiments, the top surface of the magnetic stacked layer structure is arc-shaped. Specifically, the first magnetic layer 530a, the spacer material layer 520a, and the second magnetic layer 510a may be etched by an ion beam etching (IBE) process to form the magnetic stacked layer structure, and the top surface of the free layer <NUM> of the magnetic stacked layer structure is arc-shaped, which can increase the distance between the upper parts of the adjacent magnetic stacked layer structures, thus reduce the risk of adjacent magnetic stacked layer structures contacting each other, therefore increasing the product yield. At the same time, it is also conducive to better space filling of the subsequent third dielectric layer between the adjacent magnetic stacked layer structures.

Referring to <FIG>, step S150 is performed to form a second shielding layer 200b on the top and side walls of the storage structure, and the first shielding layer 200a and the second shielding layer 200b combine to form the shielding layer <NUM>. Specifically, the step S150 includes: deposing a shielding material on the storage structure through a deposition process to form a second shielding layer 200b which covers the top surface and sidewalls of the storage structure. The second shielding layer 200b is connected to the first shielding layer 200a so they combine to be a shielding layer <NUM> on the storage structure <NUM>. The deposition process includes chemical vapor deposition (CVD), physical vapor deposition (PVD), or atomic layer deposition (ALD). The shielding material can be a material with good conductivity, such as silver (Ag), copper (Cu), gold (Au), etc., these materials can play a good shielding effect on the electric field; the shielding material can also be a material with good magnetic permeability, such as iron (Fe), cobalt (Co) and nickel (Ni) and their alloys, such as cobalt-iron, nickel-iron and nickel-cobalt-iron, or various combinations of NiFe and Co and other alloys with higher magnetic permeability, doped amorphous ferromagnetic alloys and so like. It should be noted that the material with good conductivity can play an additional certain shielding effect on the magnetic field, and the material with good magnetic permeability can also play a certain shielding effect on the electric field.

In one of the embodiments, the materials of the first shielding layer 200a and the second shielding layer 200b are different. The first shielding layer 200a and the second shielding layer 200b are both materials with good magnetic permeability, but the materials of the first shielding layer 200a and the second shielding layer 200b are different. For example, the first shielding layer 200a is made of cobalt-iron, and the second shielding layer 200b is made of nickel-iron; or the first shielding layer 200a and the second shielding layer 200b are both materials with good conductivity, but the materials of the first shielding layer 200a and the second shielding layer 200b are different. For example, the first shielding layer 200a is silver, and the second shielding layer 200b is copper. Or the first shielding layer 200a is made of a material with good electric conductivity such as copper, and the second shielding layer 200b is made of a material with good magnetic permeability, such as nickel-iron. As shown in <FIG>, the first shielding layer 200a and the second shielding layer 200b have an etch selection ratio, as self-aligned etching is used to remove part of the sidewalls of the magnetic stacked layer structure. The second shielding layer 200b is patterned and the first shielding layer 200a remains under the second shielding layer 200b. That is, the first shielding layer 200a and the second shielding layer 200b over the sidewalls of the magnetic stacked layer structure form the resultant shielding layer <NUM>. This method can reduce process steps and save fabrication costs. At the same time, self-aligned etching can be used to prevent over-etching errors caused by the photolithography process and improve product yield.

In one of the embodiments, referring to <FIG>, before the second shielding layer is formed on the top surface and sidewalls of the storage structure, the method further includes: forming a second dielectric layer 300b covering the top surface and sidewalls of the magnetic stacked layer structure. Two dielectric layers, the first dielectric layer 300a and the second dielectric layer 300b together constitute an isolation layer <NUM>. Specifically, the process includes: using a deposition process to deposit an isolation material, such as silicon oxide, silicon nitride, or silicon oxynitride, to form a second dielectric layer 300b covering the first dielectric layer 300a and the top surface and sidewalls of the magnetic stacked layer structure. Then, an etching process is used to remove the portion of the second dielectric layer 300b from the upper surface of the first dielectric layer 300a to form the portion of the second dielectric layer 300b covering only the top surface and sidewalls of the magnetic stacked layer structure. In this embodiment, referring to <FIG>, the first dielectric layer 300a and the second dielectric layer 300b compose of the same material. Therefore, the first dielectric layer 300a and second dielectric layer between adjacent magnetic stacked layer structures can also be removed by one etching process, and the first dielectric layer 300a and the second dielectric layer 300b retain on the top surface and sidewalls of the magnetic stacked layer structures. The first dielectric layer 300a and the second dielectric layer 300b jointly constitute an isolation layer <NUM>. The isolation layer can relieve the stress of the shielding layer <NUM> and isolate the shielding layer <NUM> from the magnetic stacked layer structure.

In one of the embodiments, the lateral dimension of the magnetic stacked layer structure is larger than the lateral dimension of the first electrode. Specifically, as shown in <FIG>, the size of the magnetic in the direction along the surface of the substrate <NUM> is larger than the size of the first electrode <NUM> in the direction along the surface of the substrate <NUM>, so that a part of the shielding layer <NUM> is also formed between the substrate <NUM> and the magnetic stacked layer structure. The formed shielding layer <NUM> also has a certain shielding effect at the bottom of the magnetic stacked layer structure to enhance the shielding effect.

Referring to <FIG> and <FIG>, step S160 is performed to form a second electrode <NUM> that penetrates the shielding layer <NUM> and is electrically connected to the storage structure. Specifically, step S160 includes: forming a third dielectric layer <NUM> on the substrate <NUM> and the storage structure; forming a third opening <NUM> in the third dielectric layer <NUM> to expose the top of the storage structure <NUM> through photolithography and etching processes. Finally, the third opening <NUM> is filled with a conductive material, and the conductive material on the surface of the third dielectric layer <NUM> is removed by an etch-back or a chemical mechanical polishing process to form the second electrode <NUM>. The second electrode layer may be a metal material layer with good conductivity such as Al, W, and Cu.

In one example, as shown in <FIG> and <FIG>, the method further includes forming a second electrode that is electrically connected to the storage structure. The storage structure is a magnetic stacked layer structure. The top of the stacked layer structure is arc-shaped. The third dielectric layer <NUM> is formed on the substrate as well as the magnetic stacked layer structure. A part of the shielding layer above the magnetic stacked layer structure is removed by a planarization process to expose the magnetic stacked layer top. The fourth dielectric layer <NUM> is formed on the top of the magnetic stacked layer structure. A second opening (not shown in the figure) is formed in the fourth dielectric layer <NUM> to expose the top of the magnetic stacked layer structure. The second electrode <NUM> is formed in the second opening. Using a planarization process to remove part of the shielding layer above the magnetic stacked layer structure to expose the top of the magnetic stacked layer structure can simplify the manufacturing process. At the same time, when the second opening is subsequently formed, the shielding layer and the isolation layer are etched to reduce damage to the magnetic stacked layer structure; while the arc-shaped top structure can make the non-exposed area of the magnetic stacked layer structure when the top of the magnetic stacked layer structure is exposed by a planarization process. The external unexposed isolation layer and shielding layer will not be removed, thereby enhancing the shielding effect. In this example, the bottom surface of the second electrode <NUM> and the top surface of the magnetic stacked layer structure, the top surface of the shielding layer <NUM> and the top surface of the isolation layer <NUM> are on the same horizontal plane.

Based on the present invention, a semiconductor structure is also provided. Referring to <FIG>, the semiconductor structure includes: a substrate <NUM>, a first electrode <NUM>, a storage structure <NUM>, a shielding layer <NUM>, and a second electrode <NUM>. The first electrode <NUM> is located in the substrate <NUM>; the storage structure <NUM> is located on the first electrode <NUM>; the shielding layer <NUM> covers the top surface and sidewalls of the storage structure <NUM>, and the bottom surface of the shielding layer <NUM> is lower than the bottom surface of the storage structure <NUM>; the second electrode <NUM> penetrates the shielding layer <NUM> into the top of the storage structure <NUM> and is electrically connected to the storage structure <NUM>.

The shielding layer <NUM> covers the storage structure <NUM>, which can better shield the interference of the external electromagnetic field on the storage structure <NUM>, and ensure that information can be stored and read and written correctly. The substrate <NUM> may be one of, but not limited to, a silicon substrate, an epitaxially grown silicon substrate, a silicon germanium substrate, a silicon carbide substrate, or a silicon-on-insulator substrate. The substrate <NUM> may include device structures, such as semiconductor transistors and interconnecting contacts to connect the semiconductor transistors.

In the invention, there are multiple storage structures <NUM>, multiple first electrodes <NUM>, and multiple second electrodes <NUM>. The first electrode <NUM> and the second electrode <NUM> are arranged in a one-to-one correspondence with the storage structure <NUM>. There are spaces between any two of the storage structures <NUM>. The semiconductor structure further includes a third dielectric layer <NUM> disposed on the substrate <NUM>, and the spaces between two of the storage structures <NUM> are filled to isolate two adjacent second electrodes <NUM> and two adjacent shielding layers <NUM>. In this embodiment, the third dielectric layer <NUM> may be formed of dielectric materials such as silicon nitride, silicon oxide, or silicon oxynitride.

In one of the embodiments, the storage structure <NUM> is a magnetic stacked layer structure. The magnetic stacked layer structure at least includes a free layer <NUM>, a spacer layer <NUM>, and a fixed layer <NUM> stacked from top to bottom. Specifically, the materials of the free layer <NUM> and the fixed layer <NUM> include Co, Fe, B, Ta or Ru; the material of the spacer layer includes Mg or O. For example, the fixed layer <NUM> may be CoFeB, the spacer layer may be a MgO layer, and the free layer <NUM> may be CoFeB.

In one of the embodiments, an isolation layer <NUM> is further included, and the isolation layer <NUM> is at the magnetic stacked layer structure. Specifically, the isolation layer <NUM> includes a first dielectric layer 300a and a second dielectric layer 300b; the first dielectric layer 300a is located between the shielding layer <NUM> and the first electrode <NUM>; the second dielectric layer 300b is located between the shielding layer <NUM> and the magnetic stacked layer structure.

In one of the embodiments, the top of the magnetic stacked layer structure is arc-shaped. As shown in <FIG>, the top of the magnetic stacked layer structure is arc-shaped, and the top surfaces of the isolation layer <NUM> and the shielding layer <NUM> covered thereon are also arc-shaped. Specifically, the arc shape is outwardly protruding, and the top surface of the free layer <NUM> in the magnetic stacked layer structure has an arc shape. This structure keeps a larger distance between tops of two adjacent magnetic stacked layer structures, thus reducing the risk of adjacent magnetic stacked layer structures contacting each other, and increasing the product yield. At the same time, it also facilitates filling the third dielectric layer <NUM> in the spaces between any two of the adjacent magnetic stacked layer structures. In addition, as shown in <FIG>, the arc-shaped magnetic stacked layer structure tops can prevent the isolation layer <NUM> and the shielding layer <NUM> outside the non-exposed region of the magnetic stacked layer structure from being removed when the magnetic stacked layer structure top is exposed by a planarization process. As the result, the shielding effect is enhanced.

In some of the embodiments, the lateral dimension of the magnetic stacked layer structure is larger than the lateral dimension of the first electrode. As shown in <FIG>, the dimension of the magnetic stacked layer structure parallel to the surface of the substrate <NUM> is larger than the dimension of the first electrode <NUM> parallel to the surface of the substrate <NUM>, so that a part of the shielding layer <NUM> is also formed between the substrate <NUM> and the magnetic stacked layer structure, that is, a part of the shielding layer <NUM> is also formed at the bottom of the magnetic stacked layer structure and the shielding layer <NUM> also plays a certain shielding role at the bottom of the magnetic stacked layer structure, increasing the total shielding effect.

In one of the embodiments, as shown in <FIG>, the shielding layer <NUM> includes a first shielding layer 200a and a second shielding layer 200b; the first shielding layer 200a is located between the first dielectric layer 300a and the liner. Between the substrate <NUM>, one end of the first shielding layer 200a is located in the projected area of the magnetic stacked layer structure on the substrate <NUM>; the second shielding layer 200b is located on the outer surface of the sidewalls and the outer surface of the second dielectric layer 300b of the first dielectric layer 300a. The ends of the first shielding layer 200a and the second shielding layer 200b are connected to form a shielding layer <NUM> covering the top, sidewalls and part of the bottom surface of the magnetic stacked layer structure.

In one of the embodiments, the material of the first shielding layer 200a and the second shielding layer 200b can be one with good conductivity, such as silver, copper, gold, etc., which can effectively shield the electric field. The materials of the first shielding layer 200a and the second shielding layer 200b may also be materials with good magnetic permeability, such as alloys including iron (Fe), cobalt (Co), and nickel (Ni), or cobalt-iron, nickel-iron, and nickel, cobalt iron, various combinations of NiFe and Co alloys with higher magnetic permeability, doped amorphous ferromagnetic alloys, etc. It should be noted that the material with good conductivity can also play a certain shielding effect on the magnetic field, and the material with good magnetic permeability can also play a certain shielding effect on the electric field.

In one of the embodiments, the materials of the first shielding layer 200a and the second shielding layer 200b are different. For example, the first shielding layer 200a and the second shielding layer 200b may be both materials with good magnetic permeability. The materials of the first shielding layer 200a and the second shielding layer 200b can also be different, for example, the first shielding layer 200a and the second shielding layer 200b may be made of different materials. The layer 200a is cobalt-iron, and the second shielding layer 200b is nickel-iron; or the first shielding layer 200a and the second shielding layer 200b are both materials with good conductivity, but the first shielding layer 200a and the second shielding layer 200b may have different materials. For example, the first shielding layer 200a is silver and the second shielding layer 200b is copper; or the first shielding layer 200a is a material with good conductivity, such as copper. The second shielding layer 200b is made of a material with good magnetic permeability, such as nickel-iron. As shown in <FIG>, the first shielding layer 200a and the second shielding layer 200b have different etch rates which presents an etch selection ratio. A self-aligned etching process is used to remove the first shielding layer 200a out of the sidewalls of the first electrode <NUM>. The first shielding layer 200a and the second shielding layer 200b remaining next to the sidewalls of the first electrode <NUM> form the resultant shielding layer <NUM>. This method can reduce process steps and save costs. At the same time, self-aligned etching can be used to prevent over-etching errors caused by the photolithography process and improve product yield.

In one example, as shown in <FIG>, the bottom surface of the second electrode <NUM> is in contact with the top surface of the magnetic stacked layer structure, the top surface of the shielding layer <NUM>, and the top surface of the isolation layer <NUM> on the same level. Specifically, as shown in <FIG> and <FIG>, the storage structure <NUM> is a magnetic stacked layer structure; the top of the magnetic stacked layer structure is arc-shaped. A third dielectric layer <NUM> is formed on the substrate <NUM> and the magnetic stacked layer structure. A planarization process is used to remove part of the shielding layer <NUM> from above the magnetic stacked layer structure to expose the top of the magnetic stacked layer structure; a fourth dielectric layer <NUM> is formed on the top surface of the magnetic stacked layer structure. A second opening (not shown) is formed in the fourth dielectric layer <NUM> to expose the top of the magnetic stacked layer structure; the second electrode <NUM> is formed in the second opening. Using a planarization process to remove part of the shielding layer <NUM> above the magnetic stacked layer structure to expose the top can simplify the manufacturing process, and at the same time, when the second opening is subsequently formed, the shielding layer and the isolation layer are etched to reduce damage to the magnetic stacked layer structure. The arc-shaped top structure can make the magnetic stacked layer structure unexposed when the top of the magnetic stacked layer structure is exposed by a planarization process. The isolation layer <NUM> and the shielding layer <NUM> outside the area will not be removed, thereby enhancing the shielding effect. In this example, the bottom surface of the second electrode <NUM> and the top surface of the magnetic stacked layer structure, the top surface of the shielding layer <NUM> and the top surface of the isolation layer <NUM> share the same horizontal plane.

The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the various technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, all should be considered as in the scope of this specification.

Claim 1:
A semiconductor structure, comprising:
a substrate (<NUM>);
a first electrode (<NUM>) disposed in the substrate (<NUM>);
a storage structure (<NUM>) formed on the first electrode (<NUM>), wherein the storage structure (<NUM>) comprises a magnetic stacked layer structure;
a first shielding layer (200a) formed on the substrate (<NUM>), wherein the first electrode (<NUM>) penetrates the first shielding layer (200a);
a first dielectric layer (300a) formed on the first shielding layer (200a), wherein the first electrode (<NUM>) is disposed in the first dielectric layer (300a), and a top surface of the first electrode (<NUM>) is flush with a top surface of the first dielectric layer (300a);
a second dielectric layer (300b) formed on the first dielectric layer (300a) and covering a top surface and sidewalls of the magnetic stacked layer structure, wherein the first dielectric layer (300a) and the second dielectric layer (300b) together constitute an isolation layer (<NUM>);
and a second electrode (<NUM>) penetrating the shielding layer (<NUM>) at the top surface of the magnetic stacked layer structure and electrically connects to the storage structure (<NUM>);
characterized in that the semiconductor structure further comprises:
a second shielding layer (200b) formed on the first shielding layer (200a) and formed on an outer surface of the isolation layer (<NUM>), wherein the first shielding layer (200a) and the second shielding layer (200b) together constitute a shielding layer (<NUM>) covering the top surface and the sidewalls of the magnetic stacked layer structure, and a bottom surface of the shielding layer (<NUM>) is lower than a bottom surface of the storage structure (<NUM>), and wherein a material of the first shielding layer (200a) is different from a material of the second shielding layer (200b) and the material of the first shielding layer (200a) and the material of the second shielding layer (200b) each comprises a conductive material or a magnetically permeable material.