Semiconductor Structure and Method of Forming the Same

Abstract

A semiconductor structure and a method for forming the same, wherein the method includes: providing a substrate; forming a bottom electromagnetic material film on the surface of the substrate; forming a precursor film on the surface of the bottom electromagnetic material film; forming a first insulating film on the surface of the precursor film; performing an annealing treatment to form a second insulating film from the precursor film; and forming a top electromagnetic material film on the surface of the first insulating film. The method can improve the performance of the formed semiconductor structure.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor manufacturing, and particularly relates to a semiconductor structure and a method for forming the same. Background Art

[0002] MRAM (Magnetic Random Access Memory) is a non-volatile magnetic random access memory. It has the high-speed read and write capabilities of static random access memory (SRAM), the high integration of dynamic random access memory (DRAM), and its power consumption is far lower than that of DRAM. Compared with flash memory (Flash), its performance does not degrade with the increase of usage time. Due to the above characteristics of MRAM, it is called universal memory and is considered capable of replacing SRAM, DRAM, EEPROM, and Flash.

[0003] Different from the manufacturing technology of traditional random access memory chips, the data in MRAM is not stored in the form of charge or current, but in a magnetic state, and is sensed by measuring resistance without disturbing the magnetic state. MRAM uses a magnetic tunnel junction (MTJ) structure for data storage. Generally, an MRAM cell consists of a transistor (1T) and a magnetic tunnel junction (MTJ) to form a storage cell together. The magnetic tunnel junction (MTJ) structure includes at least two electromagnetic layers and an insulating layer for isolating the two electromagnetic layers. Current vertically flows through or "crosses" another electromagnetic layer from one electromagnetic layer through the insulating layer. One of the electromagnetic layers is a fixed magnetic layer, and the electrode is fixed in a specific direction through a strong fixing field. The other electromagnetic layer is a freely rotatable magnetic layer, and the electrode is held in one of the two directions.

[0004] However, the performance of the magnetic tunnel junctions prepared by the prior art is poor. Summary of the Invention

[0005] The technical problem solved by the present invention is to provide a semiconductor structure and a method for forming the same to improve the performance of the formed semiconductor structure.

[0006] To solve the above technical problem, the technical solution of the present invention provides a method for forming a semiconductor structure, including: providing a substrate; forming a bottom electromagnetic material film on the surface of the substrate; forming a precursor film on the surface of the bottom electromagnetic material film; forming a first insulating film on the surface of the precursor film; and forming a top electromagnetic material film on the surface of the first insulating film.

[0007] Optionally, the material of the precursor film includes: magnesium, aluminum, hafnium, or zirconium.

[0008] Optionally, the method for forming the precursor film includes: forming an insulating material film on the surface of the bottom electromagnetic material film, and the material of the insulating material film is a metal oxide; performing a modification treatment on the insulating material film to remove oxygen in the material of the insulating material film, so that the insulating material film forms a precursor film.

[0009] Optionally, the thickness range of the insulating material film is 0 Å to 500 Å.

[0010] Optionally, the metal oxide includes: magnesium oxide, aluminum oxide, hafnium dioxide or zirconium dioxide.

[0011] Optionally, the forming process of the insulating material film includes: chemical vapor deposition process or physical vapor deposition process.

[0012] Optionally, the method for the modification treatment includes: performing a reduction treatment on the insulating material film to remove oxygen in the material of the insulating material film; the process parameters of the reduction treatment include: the gases used include: hydrogen and helium, the flow rate of hydrogen is 50 standard milliliters per minute to 5000 standard milliliters per minute, the flow rate of helium is 0 standard milliliters per minute to 10000 standard milliliters per minute, the temperature is 25 degrees Celsius to 150 degrees Celsius, and the time is 1 second to 120 minutes.

[0013] Optionally, the forming process of the precursor film includes: chemical vapor deposition process or physical vapor deposition process.

[0014] Optionally, the forming process of the first insulating film includes: chemical vapor deposition process, physical vapor deposition process or atomic layer deposition process; the material of the first insulating film includes: one or several combinations of magnesium oxide, aluminum oxide, silicon nitride, silicon oxynitride, hafnium dioxide and zirconium dioxide.

[0015] Optionally, the method for forming the first insulating film includes: performing an oxidation treatment on the precursor film to make the precursor film form a first insulating film, and the thickness of the first insulating film is less than or equal to the thickness of the precursor film; the thickness range of the first insulating film is 0 Å to 500 Å.

[0016] Optionally, the material of the first insulating film includes: magnesium oxide, aluminum oxide, hafnium dioxide or zirconium dioxide.

[0017] Optionally, it further includes: before forming the top electromagnetic material film on the surface of the first insulating film, performing an annealing treatment to make the precursor film form a second insulating film, and the second insulating film is located at the bottom of the first insulating film; the temperature range of the annealing treatment is 300 degrees Celsius to 400 degrees Celsius.

[0018] Optionally, a conductive layer is provided in the substrate, and the surface of the conductive layer is exposed on the substrate; the bottom electromagnetic material film is located on the surfaces of the substrate and the conductive layer.

[0019] Optionally, the bottom electromagnetic material film includes: a lower electrode film located on the surfaces of the substrate and the conductive layer, a lower composite film located on the surface of the lower electrode film, and a lower electromagnetic film located on the surface of the lower composite film.

[0020] Optionally, the material of the lower electrode film includes one or a combination of several of: copper, tungsten, aluminum, titanium, titanium nitride, tantalum; the lower composite film is a single-layer structure or a composite structure; the material of the lower electromagnetic film includes one or a combination of several of: iron, platinum, cobalt, nickel, cobalt iron boron, cobalt iron, nickel iron, and lanthanum strontium manganite.

[0021] Optionally, when the lower composite film is a single-layer structure, the material of the lower composite film includes one of: iron, platinum, cobalt, nickel, cobalt iron boron, cobalt iron, nickel iron, or lanthanum strontium manganite; when the lower composite film is a composite structure, the lower composite film includes several overlapping conductive layers, and the material of each conductive layer includes one or a combination of several of: iron, platinum, cobalt, nickel, cobalt iron boron, cobalt iron, nickel iron, and lanthanum strontium manganite.

[0022] Optionally, the top electromagnetic material film includes: an upper electromagnetic film located on the surface of the first insulating film, an upper composite film located on the surface of the upper electromagnetic film, and an upper electrode film located on the surface of the upper composite film.

[0023] Optionally, further included is: after forming the top electromagnetic material film, patterning the top electromagnetic material film, the first insulating film, the second insulating film, and the bottom electromagnetic material film until the surface of the substrate is exposed, so that the top electromagnetic material film forms a top electromagnetic layer, the first insulating film forms a first insulating layer, the second insulating film forms a second insulating layer, and the bottom electromagnetic material film forms a top electromagnetic layer, and a magnetic tunnel junction is formed on the surface of the substrate.

[0024] Optionally, the method for patterning the top electromagnetic material film, the first insulating film, the second insulating film, and the bottom electromagnetic material film includes: forming a patterning layer on the surface of the top electromagnetic material film, and the patterning exposes a part of the surface of the top electromagnetic material film; using the patterning layer as a mask, etching the top electromagnetic material film, the first insulating film, the second insulating film, and the bottom electromagnetic material film until the surface of the substrate is exposed, to form the magnetic tunnel junction, and the magnetic tunnel junction includes: a bottom electromagnetic layer located on the surface of the substrate, a second insulating layer located on the surface of the bottom electromagnetic layer, a first insulating layer located on the surface of the second insulating layer, and a top electromagnetic layer located on the surface of the first insulating layer.

[0025] Correspondingly, the technical solution of the present invention provides a semiconductor structure formed by using any of the above methods.

[0026] Compared with the prior art, the technical solution of the embodiment of the present invention has the following beneficial effects:

[0027] In the method for forming a semiconductor structure provided by the technical solution of the present invention, during the process of forming the first insulating film on the surface of the precursor film, since the material of the precursor film can effectively block the ions in the deposition process of forming the first insulating film from diffusing into the underlying electromagnetic material film, it is possible to avoid the deposition process of forming the first insulating film from affecting the underlying electromagnetic material film. At the same time, through annealing treatment, the precursor film is formed into a second insulating film, and the second insulating film provides materials for the non-magnetic insulating layer in the subsequent formation of the magnetic tunnel junction. In summary, the semiconductor structure formed by the method has good performance.

[0028] Further, before the subsequent formation of the first insulating film, a precursor film has been formed on the surface of the underlying electromagnetic material film, so as to ensure that during the subsequent formation of the first insulating film, the precursor film can block the diffusion of ions into the underlying electromagnetic material film.

[0029] Further, the significance of selecting the thickness range of the insulating material film is as follows: if the thickness is less than 0 Å, ions will diffuse into the underlying electromagnetic material film during the subsequent deposition process of forming the first insulating film, resulting in poor performance of the formed semiconductor structure; if the thickness is greater than 500 Å, the process of forming the insulating material film will still affect the underlying electromagnetic material film, which is not conducive to improving the performance of the formed semiconductor structure.

[0030] Further, by oxidizing the precursor film, the precursor film is formed into a first insulating film, and the thickness of the first insulating film is less than or equal to the thickness of the precursor film. Using the precursor film as a precursor layer to form the first insulating film is beneficial to saving costs and process time. At the same time, by controlling the process parameters of the oxidation treatment, when the precursor film is formed into the first insulating film, that is, when a part of the precursor film is ensured to remain, or when the precursor film is just completely formed into the first insulating film, the oxidation treatment process is stopped, which can avoid the oxidation treatment process from affecting the underlying electromagnetic material film and make the performance of the formed semiconductor structure better.

[0031] Furthermore, through annealing treatment, the material of the precursor film can be oxidized to form a second insulating film. The second insulating film and the first insulating film together serve as the insulating layer for forming the magnetic tunnel junction subsequently. By controlling the time of the annealing treatment to control the process of oxidizing the precursor film, since the temperature of the annealing treatment is appropriately selected, it is beneficial to accurately control the oxidation rate of the precursor film, so that by controlling the time parameter of the annealing process, it is possible to satisfy the condition that the material of the precursor film is fully oxidized to form the second insulating film, while ensuring that the precursor film can form a second insulating film with better insulation performance without affecting the underlying electromagnetic material film, resulting in better performance of the formed semiconductor structure.

[0032] Furthermore, the temperature range of the annealing treatment is 300 degrees Celsius to 400 degrees Celsius. The significance of selecting this temperature range is as follows: If the temperature is greater than 400 degrees Celsius, the temperature is too high. On the one hand, it is easy to cause high-temperature effects on the material. On the other hand, the oxidation rate is too fast at too high a temperature, which is likely to cause over-oxidation of the materials of the first insulating film and the second insulating film, resulting in a reduction in the insulation performance of the first insulating film and the second insulating film; if the temperature is less than 300 degrees Celsius, the temperature is too low, resulting in too low an efficiency of oxidizing the precursor film to form the second insulating film, which is not conducive to improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figures 1 to 4 is a schematic structural diagram of each step of a method for forming a semiconductor structure;

[0034] Figures 5 to 15 is a schematic structural diagram of each step of a method for forming a semiconductor structure in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0035] As described in the background art, the performance of existing semiconductor structures is poor.

[0036] The following will be described in detail with reference to the drawings the reasons for the poor performance of the semiconductor structure. Figures 1 to 4 is a schematic structural diagram of a semiconductor structure.

[0037] Please refer to Figure 1 , a substrate 100 is provided, and a conductive layer 110 is provided inside the substrate 100, and the surface of the conductive layer 110 is exposed on the substrate 100.

[0038] Please refer to Figure 2 , a bottom electromagnetic material film 120 is formed on the surface of the substrate 100 and the surface of the conductive layer 110.

[0039] Please refer to Figure 3 , an insulating film 130 is formed on the surface of the bottom electromagnetic material film 120.

[0040] Please refer toFigure 4 , a top - layer electromagnetic material film 140 is formed on the surface of the insulating film 130.

[0041] In the above - mentioned method, a bottom - layer electromagnetic material film 120 is formed on the surface of the substrate 100 and the surface of the conductive layer 110; an insulating film 130 is formed on the surface of the bottom - layer electromagnetic material film 120; a top - layer electromagnetic material film 140 is formed on the surface of the insulating film 130, and the bottom - layer electromagnetic material film 120, the insulating film 130, and the top - layer electromagnetic material film 120 are used to form a magnetic tunnel junction.

[0042] However, since the insulating film 130 usually has a certain thickness, during the formation of the insulating film 130, ions in the deposition process are likely to diffuse into the bottom - layer electromagnetic material film 120, affecting the material of the bottom - layer electromagnetic material film 120. As a result, the stability of the formed magnetic tunnel junction is poor, leading to poor performance of the formed semiconductor structure.

[0043] To solve the above - mentioned technical problems, an embodiment of the present invention provides a method for forming a semiconductor structure, including: providing a substrate; forming a bottom - layer electromagnetic material film on the surface of the substrate; forming a precursor film on the surface of the bottom - layer electromagnetic material film; forming a first insulating film on the surface of the precursor film; performing an annealing treatment to make the precursor film form a second insulating film; and forming a top - layer electromagnetic material film on the surface of the first insulating film. The semiconductor structure formed by this method has good performance.

[0044] To make the above - mentioned objects, features, and beneficial effects of the present invention more obvious and understandable, the following detailed description of the specific embodiments of the present invention is provided with reference to the accompanying drawings.

[0045] Figures 5 to 15 is a schematic structural diagram of each step of the method for forming a semiconductor structure in an embodiment of the present invention.

[0046] Please refer to Figure 5 , and a substrate 200 is provided.

[0047] In this embodiment, the substrate 200 has a conductive layer 210 therein, and the substrate 200 exposes the surface of the conductive layer 210.

[0048] In this embodiment, the substrate 200 includes: a substrate (not shown in the figure) and a dielectric layer (not shown in the figure) located on the surface of the substrate, and the conductive layer 210 is located within the dielectric layer.

[0049] The material of the substrate is a semiconductor material. In this embodiment, the material of the substrate is silicon. In other embodiments, the material of the substrate includes silicon carbide, silicon germanium, a multi - semiconductor material composed of group III - V elements, silicon - on - insulator (SOI), or germanium - on - insulator.

[0050] In this embodiment, a device structure is provided in the substrate, and the device structure includes one or more of a PMOS transistor, an NMOS transistor, a CMOS transistor, a resistor, a capacitor, and an inductor.

[0051] The material of the dielectric layer includes: silicon oxide, a low-K dielectric material, or an ultra-low-K dielectric material.

[0052] In this embodiment, the material of the dielectric layer is silicon oxide.

[0053] The material of the conductive layer 210 includes: one or a combination of several of copper, tungsten, aluminum, titanium, titanium nitride, and tantalum.

[0054] In this embodiment, the material of the conductive layer 210 is copper.

[0055] Please refer to Figure 6 , and a bottom electromagnetic material film 220 is formed on the surface of the substrate 200.

[0056] In this embodiment, the bottom electromagnetic material film 220 is formed on the surface of the substrate 200 and the surface of the conductive layer 210.

[0057] In this embodiment, the bottom electromagnetic material film 220 includes: a lower electrode film 221 located on the surface of the substrate 200 and the surface of the conductive layer 210, a lower composite film 222 located on the surface of the lower electrode film 221, and a lower electromagnetic film 223 located on the surface of the lower composite film 222.

[0058] The material of the lower electrode film 221 includes: one or a combination of several of copper, tungsten, aluminum, titanium, titanium nitride, and tantalum.

[0059] In this embodiment, the material of the lower electrode film 221 is tantalum.

[0060] The lower composite film 222 is a single-layer structure or a composite structure.

[0061] In this embodiment, the lower composite film 222 is a composite structure. The lower composite film 222 includes two overlapping conductive layers (not shown in the figure), the material of one conductive layer is platinum, and the material of the other conductive layer is cobalt.

[0062] In other embodiments, the material of the conductive layer may also be one or a combination of several of iron, platinum, cobalt, nickel, cobalt iron boron, cobalt iron, nickel iron, and lanthanum strontium manganite.

[0063] The material of the lower electromagnetic film 223 includes: one or a combination of several of iron, platinum, cobalt, nickel, cobalt iron boron, cobalt iron, nickel iron, and lanthanum strontium manganite.

[0064] In this embodiment, the lower electromagnetic film 223 has a single-layer structure, and the material of the lower electromagnetic film 223 is cobalt iron boron.

[0065] Next, a precursor film is formed on the surface of the bottom electromagnetic material film 220. For the specific process of forming the precursor film, please refer to Figures 7 to 8 .

[0066] Please refer to Figure 7 , an insulating material film 230 is formed on the surface of the bottom electromagnetic material film 220, and the material of the insulating material film 230 is a metal oxide.

[0067] The insulating material film 230 provides materials for forming a subsequent precursor film.

[0068] The thickness range of the insulating material film 230 is 0 Å to 500 Å.

[0069] The preferred thickness range of the insulating material film 230 is 1 Å to 100 Å.

[0070] The significance of the preferred thickness range of the insulating material film 230 being 1 Å to 100 Å is as follows: If the thickness is less than 1 Å, the thickness of the subsequent precursor film is too thin, and during the process of subsequently depositing and forming the first insulating film, the precursor film still cannot sufficiently block the diffusion of ions into the bottom electromagnetic material film 220 at the bottom of the precursor film, resulting in poor performance of the formed semiconductor structure; if the thickness is greater than 100 Å, the process of forming the insulating material film will still affect the bottom electromagnetic material film 220, which is not conducive to improving the performance of the formed semiconductor structure.

[0071] The metal oxide includes: magnesium oxide, aluminum oxide, hafnium dioxide, or zirconium dioxide.

[0072] In this embodiment, the material of the insulating material film 230 is magnesium oxide.

[0073] Please refer to Figure 8 , the insulating material film 230 is modified to remove oxygen from the material of the insulating material film 230, so that the insulating material film 230 forms a precursor film 240.

[0074] The precursor film 240 provides materials for forming a subsequent second insulating film.

[0075] The method of the modification treatment includes: performing a reduction treatment on the insulating material film 230 to remove oxygen from the material of the insulating material film.

[0076] The process parameters of the reduction treatment include: the gases used include hydrogen and helium, the flow rate of the hydrogen is 50 standard milliliters per minute to 5000 standard milliliters per minute, the flow rate of the helium is 0 standard milliliters per minute to 10000 standard milliliters per minute, the temperature is 25 degrees Celsius to 150 degrees Celsius, and the time is 1 second to 120 minutes.

[0077] The material of the precursor film 240 includes: magnesium, aluminum, hafnium or zirconium.

[0078] In this embodiment, since the material of the insulating material film 230 is magnesium oxide, after the modification treatment, the material of the formed precursor film 240 is magnesium.

[0079] Before the first insulating film is formed subsequently, a precursor film 240 has been formed on the surface of the bottom electromagnetic material film 220, so as to ensure that during the subsequent formation of the first insulating film, the precursor film 240 can block the diffusion of ions into the bottom electromagnetic material film 220.

[0080] In other embodiments, the forming process of the precursor film 240 can also be: chemical vapor deposition process or physical vapor deposition process.

[0081] Please refer to Figure 9 , and a first insulating film 250 is formed on the surface of the precursor film 240.

[0082] The first insulating film 250 and the second insulating film formed subsequently together provide materials for the subsequent formation of the magnetic tunnel junction.

[0083] The forming process of the first insulating film 250 includes: chemical vapor deposition process, physical vapor deposition process or atomic layer deposition process.

[0084] The material of the first insulating film 250 includes: one or a combination of several of magnesium oxide, aluminum oxide, silicon nitride, silicon oxynitride, hafnium dioxide and zirconium dioxide.

[0085] In this embodiment, the material of the first insulating film 250 is the same as that of the insulating material film 230, which is magnesium oxide.

[0086] The forming process of the first insulating film 250 includes: chemical vapor deposition process, physical vapor deposition process or atomic layer deposition process.

[0087] In other embodiments, the forming method of the first insulating film includes: oxidizing the precursor film to form the first insulating film, and the thickness of the first insulating film is less than or equal to the thickness of the precursor film; the thickness range of the first insulating film is 0 angstroms to 500 angstroms.

[0088] The materials of the first insulating film include: magnesium oxide, aluminum oxide, hafnium dioxide, or zirconium dioxide.

[0089] By oxidizing the precursor film, the precursor film forms the first insulating film, and the thickness of the first insulating film is less than or equal to the thickness of the precursor film. Forming the first insulating film with the precursor film as the precursor layer is beneficial to saving costs and process time. At the same time, by controlling the process parameters of the oxidation treatment, during the process of forming the first insulating film from the precursor film, the thickness of the first insulating film is less than or equal to the thickness of the precursor film, that is, ensuring that a part of the precursor film remains, or stopping the oxidation treatment of the precursor film when the precursor film just completely forms the first insulating film, can avoid the influence of the oxidation treatment process on the underlying electromagnetic material film, making the performance of the formed semiconductor structure better.

[0090] Please refer to Figure 10 , and perform an annealing treatment to make the precursor film 240 form a second insulating film 260.

[0091] Through the annealing treatment, the material of the precursor film 240 is oxidized to form a second insulating film 260 with better insulating properties.

[0092] The temperature range of the annealing treatment is 300 degrees Celsius to 400 degrees Celsius.

[0093] The significance of selecting this temperature range is as follows: If the temperature is greater than 400 degrees Celsius, the temperature is too high. On the one hand, it is easy to cause high-temperature effects on the materials of the underlying electromagnetic material film 220 and the devices in the substrate 200. On the other hand, the oxidation rate is too fast at too high a temperature, which is easy to cause over-oxidation of the materials of the first insulating film 250 and the second insulating film 260, resulting in a decrease in the insulating properties of the first insulating film 250 and the second insulating film 260; if the temperature is less than 300 degrees Celsius, the temperature is too low, resulting in too low an efficiency of oxidizing the precursor film 240 to form the second insulating film 260, which is not conducive to improving production efficiency.

[0094] In this embodiment, the annealing treatment can also convert the amorphous or polycrystalline form of silicon oxide in the first insulating film 250 into the single-crystalline form of silicon oxide, which is beneficial to improving the performance of the first insulating film 250, thereby improving the performance of the formed semiconductor structure.

[0095] It should be noted that during the process of controlling the oxidation precursor film 240 by controlling the annealing treatment time, when the temperature of the annealing treatment is appropriately selected, it is beneficial to accurately control the oxidation rate of the precursor film 240. Therefore, by controlling the time parameter of the annealing process, it is possible to ensure that the material of the precursor film 240 is fully oxidized to form the second insulating film 260 while not affecting the underlying electromagnetic material film 220, resulting in a semiconductor structure with good performance.

[0096] Please refer to Figure 11 , after forming the second insulating film 260, a top-layer electromagnetic material film 270 is formed on the surface of the first insulating film 250.

[0097] The top-layer electromagnetic material film 270 includes: an upper electromagnetic film 271 located on the surface of the first insulating film 250, an upper composite film 272 located on the surface of the upper electromagnetic film 271, and an upper electrode film 273 located on the surface of the upper composite film 272.

[0098] The materials of the upper electromagnetic film 271 and the lower electromagnetic film 223 are the same, which will not be elaborated here.

[0099] The materials of the upper composite film 272 and the lower composite film 222 are the same, which will not be elaborated here.

[0100] The materials of the upper electrode film 273 and the lower electrode film 221 are the same, which will not be elaborated here.

[0101] In this embodiment, after forming the top-layer electromagnetic material film 270, it further includes: patterning the top-layer electromagnetic material film 270, the first insulating film 250, the second insulating film 260, and the underlying electromagnetic material film 220 until the surface of the substrate 200 is exposed, so that the top-layer electromagnetic material film forms a top-layer electromagnetic layer, the first insulating film forms a first insulating layer, the second insulating film forms a second insulating layer, and the underlying electromagnetic material film forms a top-layer electromagnetic layer, and a magnetic tunnel junction is formed on the surface of the substrate. For the specific process of forming the magnetic tunnel junction, please refer to Figures 12 to 13 .

[0102] Please refer to Figure 12 , a patterning layer 280 is formed on the surface of the top-layer electromagnetic material film 270, and the patterning layer 280 exposes a part of the surface of the top-layer electromagnetic material film 270.

[0103] The patterning layer 280 is used as a mask for subsequent etching of the top-layer electromagnetic material film 270, the first insulating film 250, the second insulating film 260, and the underlying electromagnetic material film 220.

[0104] In this embodiment, the patterning layer 280 covers the surface of the top electromagnetic material film 270 on the conductive layer 210, so that after patterning, the bottom of the formed magnetic tunnel junction is in contact with the surface of the conductive layer 210 to achieve electrical connection.

[0105] Please refer to Figure 13 , using the patterning layer 280 as a mask, etch the top electromagnetic material film 270, the first insulating film 250, the second insulating film 260, and the bottom electromagnetic material film 220 until the surface of the substrate 200 is exposed to form a magnetic tunnel junction 290.

[0106] The magnetic tunnel junction 290 includes: a bottom electromagnetic layer 291 on the surface of the substrate 200, a second insulating layer 292 on the surface of the bottom electromagnetic layer 291, a first insulating layer 293 on the surface of the second insulating layer 292, and a top electromagnetic layer 294 on the surface of the first insulating layer 293.

[0107] In this embodiment, after forming the magnetic tunnel junction 290, it further includes: removing the patterning layer 280.

[0108] In this embodiment, the method for forming the semiconductor structure further includes: after forming the magnetic tunnel junction 290, forming sidewalls on the sidewall surfaces of the magnetic tunnel junction 290, and the sidewalls are located on the surface of the substrate. For the specific process of forming the sidewalls, please refer to Figures 14 to 15 .

[0109] Please refer to Figure 14 , forming a sidewall material film 295 on the surface of the substrate 200, the top surface, and the sidewall surfaces of the magnetic tunnel junction 290.

[0110] The sidewall material film 295 provides materials for forming sidewalls subsequently.

[0111] The forming process of the sidewall material film 295 includes: chemical vapor deposition process, physical vapor deposition process, or atomic layer deposition process.

[0112] In this embodiment, the atomic layer deposition process is used to form the sidewall material film 295, so that the formed sidewall material film 295 has better thickness uniformity and high step coverage, which is conducive to forming sidewalls with uniform thickness subsequently.

[0113] The material of the sidewall material film 295 includes: silicon oxide, silicon nitride, silicon carbonitride, silicon boronitride, silicon carbon oxynitride, or silicon oxynitride.

[0114] In this embodiment, the material of the sidewall material film 295 is silicon nitride.

[0115] Please refer to Figure 15, etch back the sidewall material film 295 until the surface of the substrate 200 and the top surface of the magnetic tunnel junction 290 are exposed, thereby forming the sidewall 296.

[0116] The sidewall 293 is used to protect the magnetic tunnel junction 290, reduce the influence of subsequent processes on the magnetic tunnel junction 290, improve the integrity of the magnetic tunnel junction 290, and thus the magnetic tunnel junction 290 has a relatively high stability.

[0117] Since the material of the sidewall material film 295 is silicon nitride, correspondingly, the material of the sidewall 296 is silicon nitride.

[0118] Correspondingly, an embodiment of the present invention further provides a semiconductor structure formed by the above method.

[0119] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be determined by the scope defined by the claims.

Claims

1. A method for forming a semiconductor structure, characterized in that, Comprising: Providing a substrate; Forming a bottom electromagnetic material film on the surface of the substrate; Forming an insulating material film on the surface of the bottom electromagnetic material film, and the material of the insulating material film is a metal oxide; Performing a modification treatment on the insulating material film to remove oxygen in the material of the insulating material film, so that the insulating material film forms a precursor film, and the precursor film is located on the surface of the bottom electromagnetic material film; Performing an oxidation treatment on the precursor film to make the precursor film form a first insulating film, and the thickness of the first insulating film is less than the thickness of the precursor film; Performing an annealing treatment to make the precursor film form a second insulating film, and the second insulating film is located at the bottom of the first insulating film; Forming a top electromagnetic material film on the surface of the first insulating film; The thickness range of the insulating material film is 1 angstrom to 500 angstroms.

2. The method for forming a semiconductor structure according to claim 1, wherein, The material of the precursor film includes: magnesium, aluminum, hafnium or zirconium.

3. The method for forming a semiconductor structure as claimed in claim 1, wherein The thickness range of the insulating material film is 1 angstrom to 100 angstroms.

4. The method for forming a semiconductor structure according to claim 1, wherein, The metal oxide includes: magnesium oxide, aluminum oxide, hafnium dioxide or zirconium dioxide.

5. The method for forming a semiconductor structure according to claim 1, wherein, The forming process of the insulating material film includes: chemical vapor deposition process or physical vapor deposition process.

6. The method for forming a semiconductor structure as claimed in claim 1, wherein, The method of the modification treatment includes: performing a reduction treatment on the insulating material film to remove oxygen in the material of the insulating material film; the process parameters of the reduction treatment include: the gases used include: hydrogen and helium, the flow rate of hydrogen is 50 standard milliliters per minute to 5000 standard milliliters per minute, the flow rate of helium is 0 standard milliliters per minute to 10000 standard milliliters per minute, the temperature is 25 degrees Celsius to 150 degrees Celsius, and the time is 1 second to 120 minutes.

7. The method for forming a semiconductor structure according to claim 1, wherein, The temperature range of the annealing treatment is 300 degrees Celsius to 400 degrees Celsius.

8. The method for forming a semiconductor structure according to claim 1, wherein, The substrate has a conductive layer inside, and the substrate exposes the surface of the conductive layer; the bottom electromagnetic material film is located on the surface of the substrate and the surface of the conductive layer.

9. The method for forming a semiconductor structure according to claim 1 or 7, wherein The bottom electromagnetic material film includes: a lower electrode film located on the surface of the substrate and the surface of the conductive layer, a lower composite film located on the surface of the lower electrode film, and a lower electromagnetic film located on the surface of the lower composite film.

10. The method for forming a semiconductor structure as described in claim 9, wherein, The material of the lower electrode film includes: one or several combinations of copper, tungsten, aluminum, titanium, titanium nitride, tantalum; the lower composite film is a single-layer structure or a composite structure; the material of the lower electromagnetic film includes: one or several combinations of iron, platinum, cobalt, nickel, cobalt iron boron, cobalt iron, nickel iron and lanthanum strontium manganite.

11. The method for forming a semiconductor structure according to claim 10, wherein When the lower composite film is a single-layer structure, the material of the lower composite film includes: iron, platinum, cobalt, nickel, cobalt iron boron, cobalt iron, nickel iron or lanthanum strontium manganite; when the lower composite film is a composite structure, the lower composite film includes several overlapping conductive layers, and the material of each conductive layer includes: one or several combinations of iron, platinum, cobalt, nickel, cobalt iron boron, cobalt iron, nickel iron and lanthanum strontium manganite.

12. The method for forming a semiconductor structure according to claim 1, wherein The top electromagnetic material film includes: an upper electromagnetic film located on the surface of the first insulating film, an upper composite film located on the surface of the upper electromagnetic film, and an upper electrode film located on the surface of the upper composite film.

13. The method for forming a semiconductor structure according to claim 7, wherein, Also including: After forming the top electromagnetic material film, pattern the top electromagnetic material film, the first insulating film, the second insulating film, and the bottom electromagnetic material film until the substrate surface is exposed, so that the top electromagnetic material film forms the top electromagnetic layer, the first insulating film forms the first insulating layer, the second insulating film forms the second insulating layer, and the bottom electromagnetic material film forms the top electromagnetic layer, and form a magnetic tunnel junction on the substrate surface.

14. The method for forming a semiconductor structure according to claim 13, wherein, The method for patterning the top electromagnetic material film, the first insulating film, the second insulating film, and the bottom electromagnetic material film includes: forming a patterning layer on the surface of the top electromagnetic material film, and the patterning exposes a part of the surface of the top electromagnetic material film; using the patterning layer as a mask, etching the top electromagnetic material film, the first insulating film, the second insulating film, and the bottom electromagnetic material film until the substrate surface is exposed to form the magnetic tunnel junction, and the magnetic tunnel junction includes: a bottom electromagnetic layer located on the substrate surface, a second insulating layer located on the surface of the bottom electromagnetic layer, a first insulating layer located on the surface of the second insulating layer, and a top electromagnetic layer located on the surface of the first insulating layer.

15. A semiconductor structure formed by the method according to any one of claims 1 to 14.

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