阅读说明：本技术 Mtj器件及其制作方法以及mram (MTJ device, method of manufacturing the same, and MRAM ) 是由 毛永吉 叶甜春 罗军 赵杰 于 2021-09-03 设计创作，主要内容包括：本发明提供了一种MTJ器件及其制作方法以及MRAM,该MTJ器件包括：衬底；设置在所述衬底上的叠层结构,所述叠层结构具有多层依次层叠的功能层；所述叠层结构包括：第一部分MTJ、第二部分MTJ和第三部分MTJ；所述第一部分MTJ中任一所述功能层的延伸方向与所述第三部分MTJ中同一所述功能层的延伸方向平行,且垂直于所述第二部分MTJ中同一所述功能层的延伸方向；所述第一部分MTJ中任一所述功能层与所述第三部分MTJ中同一所述功能层位于所述第二部分MTJ中同一所述功能层的两侧。应用本发明技术方案,在提高集成度的同时,提高了器件存储性能以及可靠性。(The invention provides an MTJ device, a manufacturing method thereof and an MRAM, wherein the MTJ device comprises: a substrate; a laminated structure provided on the substrate, the laminated structure having a plurality of functional layers laminated in sequence; the laminated structure includes: a first portion MTJ, a second portion MTJ, and a third portion MTJ; the extending direction of any one functional layer in the first partial MTJ is parallel to the extending direction of the same functional layer in the third partial MTJ and perpendicular to the extending direction of the same functional layer in the second partial MTJ; any one functional layer in the first part of MTJ and the same functional layer in the third part of MTJ are positioned at two sides of the same functional layer in the second part of MTJ. By applying the technical scheme of the invention, the integration level is improved, and the storage performance and the reliability of the device are improved.)

1. An MTJ device, comprising:

a substrate;

a laminated structure provided on the substrate, the laminated structure having a plurality of functional layers laminated in sequence; the laminated structure includes: a first portion MTJ, a second portion MTJ, and a third portion MTJ;

the extending direction of any one functional layer in the first partial MTJ is parallel to the extending direction of the same functional layer in the third partial MTJ and perpendicular to the extending direction of the same functional layer in the second partial MTJ;

any one functional layer in the first part of MTJ and the same functional layer in the third part of MTJ are positioned at two sides of the same functional layer in the second part of MTJ.

2. The MTJ device of claim 1, wherein the substrate provides the surface of the stacked structure as a first surface, the first surface comprising a first region and a second region; the first area is provided with a first insulating medium layer; the third portion MTJ is located in the second region;

sequentially stacking each functional layer of the stacked structure on a preset surface;

wherein the preset surface comprises: the second area, the surface of the first insulating medium layer, which is far away from the first area, and the side face, close to the second area, of the first insulating medium layer are arranged on the first insulating medium layer.

3. The MTJ device of claim 2, wherein the multiple sequentially stacked functional layers comprise:

a first electrode layer disposed on the predetermined surface;

the reference layer is arranged on one side, away from the preset surface, of the first electrode functional layer;

the tunnel barrier layer is arranged on one side, away from the first electrode functional layer, of the reference layer;

a free layer disposed on a side of the tunnel barrier layer facing away from the reference layer;

and the second electrode layer is arranged on one side, away from the tunnel barrier layer, of the free layer.

4. The MTJ device of claim 3, in which the first surface further comprises a third region; the second region is located between the first region and the third region;

a second insulating medium layer covering the third region and the laminated structure;

the first surface is a metal layer, and the metal layer is connected with the first electrode layer; the second insulating medium layer is provided with a first through hole and a second through hole, the first through hole exposes the metal layer of the third area, and the second through hole exposes the second electrode layer;

and a wiring layer is arranged on the surface of one side, away from the substrate, of the second insulating medium layer, and the wiring layer is connected with the metal layer through the first through hole and connected with the second electrode layer through the second through hole.

5. The MTJ device of claim 3, in which the stack structure further comprises: an ohmic contact layer between the free layer and the second electrode layer.

6. A method for fabricating an MTJ device is characterized in that,

providing a substrate;

forming a laminated structure on the substrate, wherein the laminated structure is provided with a plurality of functional layers which are sequentially laminated; the laminated structure includes: a first portion MTJ, a second portion MTJ, and a third portion MTJ;

the extending direction of any one functional layer in the first part of MTJ is parallel to the extending direction of the same functional layer in the third part of MTJ, and is vertically parallel to the extending direction of the same functional layer in the second part of MTJ;

any one functional layer in the first part of MTJ and the same functional layer in the third part of MTJ are positioned at two sides of the same functional layer in the second part of MTJ.

7. The method of manufacturing according to claim 6, wherein the surface of the substrate where the laminated structure is provided is a first surface, the first surface including a first region and a second region; the first area is provided with a first insulating medium layer; the third portion MTJ is located in the second region;

the method for forming the laminated structure on the substrate comprises the following steps:

forming a first insulating medium layer in the first area;

sequentially stacking all functional layers of the stacked structure on a preset surface based on the first insulating medium layer;

wherein the preset surface comprises: the second area, the surface of the first insulating medium layer, which is far away from the first area, and the side face, close to the second area, of the first insulating medium layer are arranged on the first insulating medium layer.

8. The method according to claim 7, wherein the step of sequentially stacking each functional layer of the stacked structure on a predetermined surface based on the first insulating medium layer comprises:

forming a first electrode layer on the preset surface;

forming a reference layer on the surface of one side, away from the preset surface, of the first electrode layer;

forming a tunnel barrier layer on the surface of one side of the reference layer, which is far away from the first electrode layer;

forming a free layer on a surface of the tunnel barrier layer on a side facing away from the reference layer;

and forming a second electrode layer on the surface of the free layer on the side opposite to the tunnel barrier layer.

9. The method of manufacturing of claim 8, wherein the first surface further comprises a third region; the second region is located between the first region and the third region; the surface, facing away from the substrate, of the first insulating medium layer is provided with a fourth area and a fifth area, and the fifth area is far away from the second part of MTJ;

the manufacturing method further comprises the following steps:

forming a first sub-layer of a second insulating medium layer on the surface, away from the free layer, of the second electrode layer;

etching the first sublayer and the laminated structure to expose the third region and the fifth region;

forming a second sub-layer of the second insulating medium layer, wherein the second sub-layer covers the third area, the fifth area and the first sub-layer;

etching the second insulating medium layer to form a first through hole and a second through hole, wherein the first through hole exposes the metal layer of the third area, and the second through hole exposes the second electrode layer;

and forming a wiring layer on the surface of one side, away from the substrate, of the second insulating medium layer, wherein the wiring layer is connected with the metal layer through the first through hole and is connected with the second electrode layer through the second through hole.

10. An MRAM, comprising:

a field effect transistor and the MTJ device of claims 1-5;

a plurality of laminated metal layers are arranged between the field effect tube and the MTJ device; the lamination direction of the metal layer is directed to the MTJ device by the field effect transistor;

the field effect tube and the MTJ device are respectively connected with the adjacent metal layers.

Technical Field

The invention relates to the technical field of storage, in particular to an MTJ device, a manufacturing method thereof and an MRAM.

Background

Magnetic Random Access Memory (MRAM)) is an emerging non-volatile Memory technology, which utilizes the magnetoresistance effect of materials to store data. It has high read-write speed and high integration and can be written repeatedly for unlimited times. MRAM can not only read and write quickly and randomly, but also retain data permanently after power is removed. The core memory cell of an MRAM is a magnetic tunnel junction (MTJ device).

The MTJ device is mainly composed of a reference layer, a tunnel barrier layer, and a free layer. Generally, three layers are stacked relatively in parallel to form an MTJ device, but when the MTJ device is subjected to a two-side etching process, the magnetism of an etching interface material is weakened, the effective area of the MTJ device is reduced, and the storage performance of the device is affected.

Disclosure of Invention

In view of this, the present invention provides an MTJ device, a method for manufacturing the MTJ device, and an MRAM, so as to solve the problems of device storage performance and reliability.

In order to achieve the purpose, the invention provides the following technical scheme:

an MTJ device, comprising:

a substrate;

a laminated structure provided on the substrate, the laminated structure having a plurality of functional layers laminated in sequence; the laminated structure includes: a first portion MTJ, a second portion MTJ, and a third portion MTJ;

the extending direction of any one functional layer in the first partial MTJ is parallel to the extending direction of the same functional layer in the third partial MTJ and perpendicular to the extending direction of the same functional layer in the second partial MTJ;

any one functional layer in the first part of MTJ and the same functional layer in the third part of MTJ are positioned at two sides of the same functional layer in the second part of MTJ.

Preferably, in the MTJ device described above, a surface of the substrate on which the stacked structure is provided is a first surface, and the first surface includes a first region and a second region; the first area is provided with a first insulating medium layer; the third portion MTJ is located in the second region;

sequentially stacking each functional layer of the stacked structure on a preset surface;

wherein the preset surface comprises: the second area, the surface of the first insulating medium layer, which is far away from the first area, and the side face, close to the second area, of the first insulating medium layer are arranged on the first insulating medium layer.

Preferably, in the MTJ device described above, the plurality of functional layers stacked in this order include:

a first electrode layer disposed on the predetermined surface;

the reference layer is arranged on one side, away from the preset surface, of the first electrode functional layer;

the tunnel barrier layer is arranged on one side, away from the first electrode functional layer, of the reference layer;

a free layer disposed on a side of the tunnel barrier layer facing away from the reference layer;

and the second electrode layer is arranged on one side, away from the tunnel barrier layer, of the free layer.

Preferably, in the MTJ device described above, the first surface further includes a third region; the second region is located between the first region and the third region;

a second insulating medium layer covering the third region and the laminated structure;

the first surface is a metal layer, and the metal layer is connected with the first electrode layer; the second insulating medium layer is provided with a first through hole and a second through hole, the first through hole exposes the metal layer of the third area, and the second through hole exposes the second electrode layer;

and a wiring layer is arranged on the surface of one side, away from the substrate, of the second insulating medium layer, and the wiring layer is connected with the metal layer through the first through hole and connected with the second electrode layer through the second through hole.

Preferably, in the MTJ device described above, the stacked-layer structure further includes: an ohmic contact layer between the free layer and the second electrode layer.

The invention also provides a manufacturing method of the MTJ device, which comprises the following steps:

providing a substrate;

forming a laminated structure on the substrate, wherein the laminated structure is provided with a plurality of functional layers which are sequentially laminated; the laminated structure includes: a first portion MTJ, a second portion MTJ, and a third portion MTJ;

the extending direction of any one functional layer in the first part of MTJ is parallel to the extending direction of the same functional layer in the third part of MTJ, and is vertically parallel to the extending direction of the same functional layer in the second part of MTJ;

any one functional layer in the first part of MTJ and the same functional layer in the third part of MTJ are positioned at two sides of the same functional layer in the second part of MTJ.

Preferably, in the above manufacturing method, a surface of the substrate on which the stacked structure is provided is a first surface, and the first surface includes a first region and a second region; the first area is provided with a first insulating medium layer; the third portion MTJ is located in the second region;

the method for forming the laminated structure on the substrate comprises the following steps:

forming a first insulating medium layer in the first area;

sequentially stacking all functional layers of the stacked structure on a preset surface based on the first insulating medium layer;

wherein the preset surface comprises: the second area, the surface of the first insulating medium layer, which is far away from the first area, and the side face, close to the second area, of the first insulating medium layer are arranged on the first insulating medium layer.

Preferably, in the above manufacturing method, sequentially stacking each functional layer of the stacked structure on a predetermined surface based on the first insulating medium layer includes:

forming a first electrode layer on the preset surface;

forming a reference layer on the surface of one side, away from the preset surface, of the first electrode layer;

forming a tunnel barrier layer on the surface of one side of the reference layer, which is far away from the first electrode layer;

forming a free layer on a surface of the tunnel barrier layer on a side facing away from the reference layer;

and forming a second electrode layer on the surface of the free layer on the side opposite to the tunnel barrier layer.

Preferably, in the above manufacturing method, the first surface further includes a third region; the second region is located between the first region and the third region; the surface, facing away from the substrate, of the first insulating medium layer is provided with a fourth area and a fifth area, and the fifth area is far away from the second part of MTJ;

the manufacturing method further comprises the following steps:

forming a first sub-layer of a second insulating medium layer on the surface, away from the free layer, of the second electrode layer;

etching the first sublayer and the laminated structure to expose the third region and the fifth region;

forming a second sub-layer of the second insulating medium layer, wherein the second sub-layer covers the third area, the fifth area and the first sub-layer;

etching the second insulating medium layer to form a first through hole and a second through hole, wherein the first through hole exposes the metal layer of the third area, and the second through hole exposes the second electrode layer;

and forming a wiring layer on the surface of one side, away from the substrate, of the second insulating medium layer, wherein the wiring layer is connected with the metal layer through the first through hole and is connected with the second electrode layer through the second through hole.

The present invention also provides an MRAM, comprising:

a field effect transistor and the MTJ device described above;

a plurality of laminated metal layers are arranged between the field effect tube and the MTJ device; the lamination direction of the metal layer is directed to the MTJ device by the field effect transistor;

the field effect tube and the MTJ device are respectively connected with the adjacent metal layers.

As can be seen from the above description, in the MTJ device and the manufacturing method thereof and the MRAM provided in the technical solution of the present invention, the stack structure disposed in the MTJ device includes three parts of MTJs, and the three parts of MTJs are in a "Z" type structure, where an effective area of the Z "type MTJ device is mainly a second part of MTJ whose extending direction is perpendicular to the substrate, and the effective area of the part can be determined by a distance between two adjacent upper and lower metal layers of the MTJ device, thereby achieving an adjustment of the effective area of the MTJ device; and the first part MTJ and the third part MTJ which have magnetic change to influence the storage performance are smaller relative to the whole MTJ device, so that the effective area of the MTJ device is increased, and the storage performance of the MTJ device is improved.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, it is obvious that the drawings in the following description are only embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

It should be noted that the structures, proportions, sizes, and other dimensions shown in the drawings and described in the specification are only for the purpose of understanding and reading the present disclosure, and are not intended to limit the scope of the present disclosure, which is defined by the claims and their equivalents, and therefore do not have the essential meaning in the art, and any structural modifications, changes in proportions, or adjustments in size, without affecting the efficacy and attainment of the same, are intended to fall within the scope of the present disclosure.

FIG. 1 is a schematic diagram of a MTJ device of the prior art;

FIG. 2 is a schematic diagram of a prior art MTJ device with a metal deposition region;

FIG. 3 is a schematic structural diagram of an MTJ device according to an embodiment of the present invention;

FIGS. 4-11 are schematic flow charts illustrating a method for fabricating an MTJ device according to an embodiment of the present invention;

FIG. 12 is a schematic diagram of an MRAM structure according to an embodiment of the present invention;

FIG. 13 is a block diagram of an MRAM according to an embodiment of the present invention.

Detailed Description

Embodiments of the present application will now be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the application are shown, and in which it is to be understood that the embodiments described are merely illustrative of some, but not all, of the embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In order to make the aforementioned objects, features and advantages of the present application more comprehensible, the present application is described in further detail with reference to the accompanying drawings and the detailed description.

Referring to fig. 1, fig. 1 is a schematic structural diagram of an MTJ device commonly known in the prior art, the MTJ device including: a substrate 01; a bottom electrode layer 03, a reference layer 04, a tunnel barrier layer 05, a free layer 06, and a top electrode layer 07 laminated in this order on the surface of the substrate 01; a metal layer 02 on the surface of the top electrode layer 07 facing away from the substrate 01. The MTJ device is connected to the actual circuit through the substrate 01 and the metal layer 02.

In the prior art, in the process of the MTJ device, the bottom electrode layer 03, the reference layer 04, the tunnel barrier layer 05, the free layer 06, and the top electrode layer 07 need to be dry etched. In dry etching, the magnetism of the reference layer 04 and the free layer 06 can be changed by bombarding the surface with charged plasma, the magnetic influence exists at the interface contacted with the plasma and in the material, the influence degree is weakened along with the increase of the distance from the interface contacted with the plasma, and further, the effective area of the MTJ device is reduced, and the storage performance of the device is influenced. As shown in FIG. 1, the portions of the reference layer 04 and the free layer 06 outside the two dotted lines are regions where the plasma bombardment causes the magnetic properties to be weakened.

Because the effective area of the MTJ device is reduced due to the influence of dry etching, in order to ensure the effective MTJ size of the MTJ device, a certain area needs to be reserved in the prior art design, which is not beneficial to improving the integration level of the MTJ device, and the interference is larger when the size is smaller.

Referring to fig. 2, fig. 2 is a schematic structural diagram of an MTJ device with a metal deposition region in the prior art. During the actual etching of the MTJ device, metal deposition may occur, forming metal deposition region 08 as shown in fig. 2. The metal deposition region 08 is deposited around the bottom electrode layer 03, the reference layer 04, the tunnel barrier layer 05, the free layer 06 and the top electrode layer 07, which may cause the reference layer 04 and the free layer 06 adjacent to the tunnel barrier layer 05 above and below to be short-circuited, thereby affecting the reliability of the MTJ device.

In order to solve the above problems, the present disclosure provides an MTJ device, which improves the integration level and improves the storage performance and reliability of the device.

In order to make the aforementioned objects, features and advantages of the present application more comprehensible, the present application is described in further detail with reference to the accompanying drawings and the detailed description.

Referring to fig. 3, fig. 3 is a schematic structural diagram of an MTJ device according to an embodiment of the present invention. The MTJ device includes:

a substrate 1; a laminated structure provided on the substrate 1, the laminated structure having a plurality of functional layers laminated in this order; the laminated structure includes: a first portion MTJ, a second portion MTJ, and a third portion MTJ. In fig. 3, the stacked structure in the region above the dotted line L1 is the first MTJ, the stacked structure in the region between the dotted line L1 and the dotted line L2 is the second MTJ, and the stacked structure in the region below the dotted line L2 is the third MTJ.

The extending direction of any one functional layer in the first partial MTJ is parallel to the extending direction of the same functional layer in the third partial MTJ and perpendicular to the extending direction of the same functional layer in the second partial MTJ; any one functional layer in the first partial MTJ and the same functional layer in the third partial MTJ are located on two sides of the same functional layer in the second partial MTJ, that is, the shape of the stacked structure is "Z" shown in fig. 3.

Compared with the horizontal MTJ device in the prior art, the Z-shaped MTJ device formed by the laminated structure has the advantages that the laminating direction of the functional layers in the second part of the MTJ is parallel to the substrate 1, the space perpendicular to the substrate 1 or the gap of the same metal layer is utilized, the space is saved, and the integration level of the device is improved. The effective area of the Z-shaped MTJ device is mainly the second part of MTJ with the extension direction perpendicular to the substrate 1, and the effective area of the part can be determined by the distance between the upper metal layer and the lower metal layer (the substrate 1 and the wiring layer 11 in FIG. 3) adjacent to the MTJ device, and can be adjusted, the effective area of the MTJ device can be increased only by increasing the length of the second part of MTJ in the direction perpendicular to the substrate 1, and the first part of MTJ and the third part of MTJ with magnetic change are smaller relative to the whole MTJ device, so that the effective area calculation is more accurate, the effective area of the MTJ device is relatively increased, and the storage performance of the MTJ device is improved.

The surface of the substrate 1 on which the stacked structure is provided is a first surface including a first region and a second region. The first region has a first layer of insulating dielectric 2. The third part MTJ is located in the second region, functional layers in the third part MTJ extend in a direction parallel to the substrate 1, and a stacking direction is perpendicular to the substrate 1.

And sequentially stacking all the functional layers of the stacked structure on a preset surface. Wherein the preset surface comprises: the second area, the surface of the first insulating medium layer 2 departing from the first area, and the side surface of the first insulating medium layer 2 close to the second area. The first insulating medium layer 2 is used as a support structure to form a Z-shaped laminated structure. The first insulating medium layer 2 includes: silicon oxide. The first insulating medium layer 2 is beneficial to manufacturing the Z-shaped laminated structure, and the process is simple.

And all functional layers in the second part of MTJ are sequentially stacked on the side surface of the first insulating medium layer 2 close to the second region, the extending direction of each functional layer is perpendicular to the substrate 1, and the stacking direction is parallel to the substrate 1. Each functional layer in the first part of MTJ is arranged on the side of the first insulating medium layer 2 departing from the substrate 1, the extending square of each functional layer is parallel to the substrate 1, and the stacking direction is perpendicular to the substrate 1.

Further, the plurality of functional layers stacked in this order include: a first electrode layer 3 disposed on the predetermined surface; the reference layer 4 is arranged on one side, away from the preset surface, of the first electrode functional layer; the tunnel barrier layer 5 is arranged on one side, away from the first electrode functional layer, of the reference layer 4; a free layer 6 arranged on the side of the tunnel barrier layer 5 facing away from the reference layer 4; a second electrode layer 7 arranged on the side of the free layer 6 facing away from the tunnel barrier 5.

Wherein the first electrode layer 3 and the second electrode layer 7 are Ta or Ti; the reference layer 4 is composed of four film layers, wherein the four film layers are respectively Ru, CoFe and PtMn from top to bottom; the tunnel barrier layer 5 is MgO; the free layer 6 is CoFeB or NiFe; the reference layer 4 is a magnetic material, the magnetic direction of which is fixed; the free layer 6 is also a magnetic material, but its magnetic direction can be varied; when the magnetic direction of the free layer 6 is the same as the magnetic direction of the reference layer 4, the memory cell exhibits a low resistance state "0"; when the magnetic direction of the free layer 6 is different from the magnetic direction of the reference layer 4, the memory cell exhibits a high resistance state "1". The MTJ device stores information by the level of the resistance of the memory cell, and the process of reading the stored information of the MTJ device is to measure the resistance of the MTJ device.

The first surface of the substrate 1 further comprises a third region, the second region being located between the first region and the third region. As shown in fig. 3, the MTJ device further includes: with a second insulating dielectric layer 8 covering the third region and the stacked structure. The first surface is a metal layer, and the metal layer is connected with the first electrode layer 3; the second insulating medium layer 8 is provided with a first through hole 9 and a second through hole 10, in the direction perpendicular to the substrate 1, the second through hole 10 and the first part of MTJ are oppositely arranged, the first through hole 9 exposes the metal layer of the third area, and the second through hole 10 exposes the second electrode layer 7; the surface of one side, away from the substrate 1, of the second insulating medium layer 8 is provided with a wiring layer 11, and the wiring layer 11 is connected with the metal layer through the first through hole 9 and connected with the second electrode layer 7 through the second through hole 10.

The second insulating medium layer 8 includes: silicon oxide. The second insulating medium layer 8 is used for protecting the Z-shaped laminated structure, and the reliability of the device is improved.

The laminated structure further includes: and the ohmic contact layer is positioned between the free layer 6 and the second electrode layer 7, the ohmic contact layer is of a single-layer Ru or three-layer structure, and the three-layer structure is an upper Ru layer, a lower Ru layer and a Ta layer between the two Ru layers. The ohmic contact layer reduces the resistance between the second electrode layer 7 and the free layer 6, and improves the reliability of the MTJ device.

Based on the above embodiments, another embodiment of the present application provides a method for manufacturing an MTJ device, and referring to fig. 4 to 11, fig. 4 to 11 are schematic flow diagrams of a method for manufacturing an MTJ device according to an embodiment of the present invention, where the method includes:

step S1: a substrate 1 is provided.

Step S2: forming a laminated structure having a plurality of functional layers laminated in sequence on the substrate 1; the laminated structure includes: a first portion MTJ, a second portion MTJ, and a third portion MTJ. The extending direction of any one functional layer in the first part of MTJ is parallel to the extending direction of the same functional layer in the third part of MTJ, and is vertically parallel to the extending direction of the same functional layer in the second part of MTJ. Any one functional layer in the first part of MTJ and the same functional layer in the third part of MTJ are positioned at two sides of the same functional layer in the second part of MTJ.

Wherein, the surface of the substrate 1, which is provided with the laminated structure, is a first surface, and the first surface comprises a first area and a second area; the first area is provided with a first insulating medium layer 2; the third portion MTJ is located in the second region.

Wherein, the method for forming the laminated structure on the substrate 1 comprises the following steps:

step S2.1: referring to fig. 4, a patterned first insulating dielectric layer 2 is formed in the first region. A first insulating medium layer 2 is grown on the first surface of the substrate 1, and the first insulating medium layer 2 patterned as shown in fig. 4 is formed through a photolithography process to expose the second region and the third region.

Step S2.2: referring to fig. 5, based on the patterned first insulating medium layer 2, the functional layers of the stacked structure are sequentially stacked on a predetermined surface. Wherein the preset surface comprises: the second area, the surface of the first insulating medium layer 2 departing from the first area, and the side surface of the first insulating medium layer 2 close to the second area.

In addition, based on the first insulating medium layer 2, each functional layer of the laminated structure is sequentially laminated on a preset surface, and the method includes: forming a first electrode layer 3 on the predetermined surface; forming a reference layer 4 on the surface of one side, away from the preset surface, of the first electrode layer 3; forming a tunnel barrier layer 5 on a surface of the reference layer 4 facing away from the first electrode layer 3; forming a free layer 6 on a surface of the tunnel barrier layer 5 facing away from the reference layer 4; a second electrode layer 7 is formed on the surface of the free layer 6 on the side facing away from the tunnel barrier 5. Resulting in the structure shown in fig. 5.

Step S2.3: a first sub-layer of a second insulating medium layer 8 is formed on the surface of the second electrode layer 7 facing away from the free layer 6, so as to form the structure shown in fig. 6.

As shown in fig. 6, the first surface further includes a third area, where the third area is a first surface area around a right dotted line in the drawing, the first area is a first surface area around a left dotted line in the drawing, and the second area is located between the first area and the third area, that is, the second area is a first surface area between the left dotted line and the right dotted line in the drawing.

The surface of the first insulating medium layer 2, which is far away from the substrate 1, has a fourth area and a fifth area, the fifth area is far away from the second part MTJ, that is, the fifth area is a surface area of the first insulating medium layer 2, which is far from the substrate 1 by a left dotted line in the figure, and the fourth area is a surface area of the first insulating medium layer 2, which is far from the substrate 1 by a right dotted line in the figure.

Step S2.4: referring to fig. 7, the first sub-layer and the stacked structure are etched to expose the third region and the fifth region.

Step S2.5: referring to fig. 8, a second sub-layer of the second insulating dielectric layer 8 is formed, and the second sub-layer covers the third region, the fifth region, and the first sub-layer.

Step S2.6: referring to fig. 9, the second insulating medium layer 8 is etched to form a first through hole 9 and a second through hole 10, the first through hole 9 exposes the metal layer in the third area, and the second through hole 10 exposes the second electrode layer 7. Wherein, the etching process adopts dry etching and wet etching, and the dry etching preferentially etches one of the first through hole 9 and the second through hole 10 and then etches the other. After the dry etching, the dry etching sides of the first part of MTJ and the second part of MTJ are etched by a wet method, so that metal deposition generated by the dry etching is removed, the problem of short circuit of the device is effectively controlled, and the reliability of the device is improved.

Step S2.7: referring to fig. 10, a wiring layer 11 is formed on a surface of the second insulating medium layer 8 opposite to the substrate 1, wherein the wiring layer 11 covers the second insulating medium layer 8 and fills the first via hole 9 and the second via hole 10. The wiring layer 11 is connected to the metal layer through the first via hole 9, and is connected to the second electrode layer 7 through the second via hole 10, thereby forming the structure shown in fig. 3.

In the manufacturing method of the embodiment of the invention, the MTJ device of the embodiment can be manufactured, and the first insulating medium layer 2 is provided, and the dry etching and the wet etching are combined to form the Z-shaped laminated structure, so that the generated metal deposition can be removed, the short circuit problem of the device can be effectively controlled, and the reliability of the device can be improved.

Based on the foregoing embodiments, another embodiment of the present disclosure further provides an MRAM. Referring to fig. 12 and fig. 13, fig. 12 is a schematic structural diagram of an MRAM according to an embodiment of the present invention, and fig. 13 is a schematic structural diagram of an MRAN according to an embodiment of the present invention, where the MRAM includes: a field effect transistor and the MTJ device described above; a plurality of laminated metal layers are arranged between the field effect tube and the MTJ device; the lamination direction of the metal layer is directed to the MTJ device by the field effect transistor; the field effect tube and the MTJ device are respectively connected with the adjacent metal layers.

As shown in fig. 12, the MRAM includes: a metal layer M1 connected with the field effect transistor; a metal layer M2 located on a side of the metal layer M1 facing away from the FET; a metal layer M3 on a side of the metal layer M2 facing away from the metal layer M1; an MTJ device located on a side of the metal layer M3 facing away from the metal layer M2; a metal layer M4 located on a side of the MTJ device facing away from the metal layer M3; a metal layer M5 located on a side of the metal layer M4 facing away from the MTJ device; a metal layer M6 on a side of the metal layer M5 facing away from the metal layer M4; wherein, the field effect transistor can be NMOS.

The field effect transistor is connected with the metal layer M1 through a connecting hole T; the metal layer M1 and the metal layer M2, the metal layer M2 and the metal layer M3, the metal layer M4 and the metal layer M5, and the metal layer M5 and the metal layer M6 are all connected through insulating layers, and the MTJ device is directly connected with the metal layer M3 and the metal layer M4.

In addition, the transistor connected with the MTJ device in the MRAM can adopt a COMS field effect transistor or a fully depleted silicon-on-insulator SOI field effect transistor.

In the manner shown in fig. 12, the MTJ device is illustrated as being located between the metal layer M4 and the metal layer M3, where the metal layer M3 is the substrate 1 and the metal layer M4 is the wiring layer 11. Obviously, the MTJ device can be placed between any two adjacent metal layers M1-M6 based on the requirements.

Referring to fig. 13, the MRAM further includes: bit lines BL for reading and writing the memory cells; a word line WL for controlling the communication of the storage and BL; the source line SL. Wherein, WL is connected with the grid electrode of NMOS and BL, SL is connected with the source (drain) electrode of NMOS, BL is connected with free layer 6. The MRAM reads and stores the memorability information through the NMOS and the MTJ devices.

The MTJ device provided by the embodiment of the invention optimizes the horizontal MTJ device in the prior art into the Z-shaped MTJ device, saves space, improves the integration level and increases the adjustability of the MTJ device. And the Z-shaped MTJ device reduces the occupation ratio of the magnetic influence area in the total area, relatively increases the effective area of the MTJ device, and improves the storage performance and the calculation precision of the effective area. In addition, the manufacturing method of the MTJ device provided by the embodiment of the invention reduces the short circuit in the MTJ device and improves the reliability of the device.

The embodiments in the present specification are described in a manner of combining progression and parallelization, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

It should be noted that in the description of the present application, it is to be understood that the terms "upper", "lower", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only used for convenience in describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be configured and operated in a specific orientation, and thus, should not be construed as limiting the present application. When a component is referred to as being "connected" to another component, it can be directly connected to the other component or intervening components may also be present.

It is further noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that an article or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such article or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in an article or device that comprises the element.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.