Pinned layer of magnetic tunnel junction, magnetic memory chip and magnetic sensor chip and manufacturing methods therefor

Abstract

The present invention relates to the field of magnetic memory chips and magnetic sensor chips in integrated circuits, and in particular to a pinned layer of a magnetic tunnel junction, a magnetic memory chip and a magnetic sensor chip and manufacturing methods therefor. In general, a magnetic tunnel junction uses a Co / Pt alternating multilayer thin-film structure as a pinned layer of the magnetic tunnel junction; however, the Co / Pt alternating multilayer thin-film structure requires a substrate to have a crystalline structure matching the Co / Pt alternating multilayer thin-film structure. To prepare a matching substrate, a pinned layer of a conventional magnetic tunnel junction is generally placed closer to the substrate than a free layer, and for a dual-pinned-layer magnetic tunnel junction, a pinned layer needs to be prepared above a free layer. In the present invention, by sandwiching a ferromagnetic thin-film structure using MgO thin films at two ends, large magnetic anisotropy can be generated, and the design of the structure and process of the pinned layer is performed. The present invention provides a structure of a pinned layer that has large coercivity, generates small exchange coupling on a free layer, and can be used above the free layer of a magnetic tunnel junction, and a manufacturing process therefor.

Description

Magnetic tunnel junction fixed layer, magnetic memory chip and magnetic sensor chip, and manufacturing method thereof TECHNICAL FIELD

[0001] The present application relates to the field of magnetic memory chip and magnetic sensor chip in integrated circuit, in particular to magnetic tunnel junction fixed layer, magnetic memory chip and magnetic sensor chip, and manufacturing method thereof. BACKGROUND

[0002] A magnetic tunnel junction (MTJ) is composed of two ferromagnetic film structures (so-called structure refers to a multilayer film) sandwiching a tunneling layer insulator oxide (usually MgO). The spin direction (also known as the magnetization direction) of one ferromagnetic film structure (fixed layer) of the fixed MTJ is changed, and the spin direction of the other ferromagnetic film structure (free layer) is changed, resulting in different resistances in the parallel and anti-parallel states of the spin directions of the two ferromagnetic film structures. Therefore, it can be used in magnetic memory chips (MRAM, also known as magnetic random access memory or random read memory) and magnetic sensor chips (such as hard disk heads and other magnetic sensors).

[0003] An important issue of MRAM based on spin transfer torque (STT) MTJ is that the write electrical energy of the MTJ device is high, thereby damaging the tunneling layer insulator. STT is the change of the magnetization spin direction of the free layer caused by the magnetic moment of the spin polarization of the current in the fixed layer to perform information writing. The greater the difference between the number of upward and downward spins generated when the current is spin-polarized in the fixed layer, the smaller the write current from one state to another state (such as from parallel to anti-parallel), and the greater the write current from the opposite state (corresponding to from anti-parallel to parallel). Conversely, the opposite is also true. Therefore, a double fixed layer structure of STT-MTJ structure (Chinese patent: 202410613679.5) is proposed.

[0004] So far, the practical fixed layer is a (111) face-centered structure (fcc) Pt metal grown on a substrate, and a multilayer film of Co metal and Pt metal grown alternately on the fcc (111) face with the highest atomic density of the Pt metal serves as a fixed layer. The easy axis of magnetization of the Co metal is perpendicular to the atomic density of the crystal of the Co metal, so a strong magnetic perpendicular anisotropy is generated, and therefore the Co / Pt alternating multilayer film structure is usually used as the fixed layer of the MTJ. However, the above structure needs to be deposited on the (111) face of the face-centered Pt metal on the substrate before growth, and for the double fixed layer structure, especially the upper fixed layer in the double fixed layer magnetic tunnel junction, i.e. the fixed layer farther from the substrate, it is difficult to grow the fixed layer of the above Co / Pt alternating multilayer film structure, so it is difficult to obtain a high-quality structure and corresponding magnetic perpendicular anisotropy.

[0005] In addition, besides the STT-MTJ, the MTJ based on the spin-orbit torque (SOT) writing mode, and the MTJ based on the voltage control magnetic anisotropy (VCMA) writing mode, the fixed layer thereof will also face the same problem if not grown on the substrate (or grown later than the free layer). In addition, the magnetic sensing chip including a magnetic head also faces the same problem. SUMMARY

[0006] In view of the above background and problems, the present application provides a new structure of the MTJ fixed layer and a preparation method thereof. The present application uses the fact that the structure of the ferromagnetic thin film sandwiched by MgO films at both ends will generate a large magnetic anisotropy, and the design of the fixed layer above the free layer (i.e., farther from the substrate than the free layer) is the main starting point of the present application. The fixed layer of the present application has a larger coercivity (H c ) than the free layer, but will generate an exchange coupling magnetic field to the free layer. In order to make the fixed layer have a larger coercivity and a smaller exchange coupling magnetic field to the free layer, four structures of the ferromagnetic fixed layer structure (FP), the anti-parallel coupling ferromagnetic fixed layer structure (APP), the anti-ferromagnetic containing anti-parallel coupling ferromagnetic fixed layer (AFFP), and the anti-ferromagnetic containing anti-parallel coupling ferromagnetic fixed layer structure (AFAPP) are combined to form the final upper fixed layer, and the specific structures are as follows:

[0007] FP: Oxide coupling layer / ferromagnetic thin film structure / oxide coupling layer;

[0008] AFFP: Oxide coupling layer / ferromagnetic thin film structure / anti-ferromagnetic thin film structure;

[0009] APP: Oxide coupling layer / ferromagnetic thin film structure / anti-parallel coupling layer / ferromagnetic thin film structure / oxide coupling layer;

[0010] AFAPP: Oxide coupling layer / ferromagnetic thin film structure / anti-parallel coupling layer / ferromagnetic thin film structure / anti-ferromagnetic thin film structure.

[0011] The results show that the fixed layer prepared by this method has a high coercivity, and the exchange coupling magnetic field to the free layer can be reduced by adjustment, and at the same time, a ferromagnetic material with a large spin polarization rate such as an iron and boron alloy can also be selected to achieve it. The specific process is as follows:

[0012] The present application provides a magnetic tunnel junction for a magnetic storage chip and a magnetic sensing chip, which is composed of a ferromagnetic thin film structure serving as a free layer, a magnesium oxide film serving as a tunneling layer, and a ferromagnetic thin film structure serving as a fixed layer from near to far from the substrate;

[0013] The fixed layer ferromagnetic thin film structure is composed of an oxide coupling layer, a ferromagnetic thin film structure, an oxide coupling layer from the substrate to the far end, a ferromagnetic fixed layer structure, and an oxide coupling layer, a ferromagnetic thin film structure, an antiparallel coupling layer, a ferromagnetic thin film structure, an oxide coupling layer, and an antiparallel coupling ferromagnetic fixed layer structure. Two structures contain at least one and any one structure contains at least one structure combination.

[0014] The following is a supplement to the above: The starting point of the application is to solve the preparation method of the upper fixed layer of the double fixed layer MTJ. The lower fixed layer is ignored here, because for some single fixed layer MTJ, such as MTJ based on SOT writing mode, the fixed layer is originally above the free layer. Note that the application mentioned from the substrate to the far end. Generally, the substrate is considered as the lowermost part, and then the thin film is grown layer by layer upwards, so the farther the growth sequence is, the farther the distance from the substrate is. The ferromagnetic thin film structure refers to a structure composed of at least one layer or multiple layers of thin films containing ferromagnetic material. The structure refers to a structure composed of one or more layers of thin films. The coupling layer can also be a single layer or multiple layers of thin films.

[0015] It should be pointed out that the ferromagnetic fixed layer structure (FP) and the antiparallel coupling ferromagnetic fixed layer structure (APP) of the two structures can share the adjacent parts such as the oxide coupling layer when either one or both structures are combined singly or in multiple. The MgO of the tunneling layer can also be shared.

[0016] According to the application, the magnetic tunnel junction for magnetic storage chip and magnetic sensing chip is composed of any one of the fixed layer farthest from the substrate, which is composed of an oxide coupling layer, a ferromagnetic thin film structure, an antiferromagnetic thin film structure, and an antiferromagnetic ferromagnetic fixed layer structure, and an oxide coupling layer, a ferromagnetic thin film structure, an antiparallel coupling layer, a ferromagnetic thin film structure, and an antiferromagnetic thin film structure.

[0017] The following is a supplement to the above: The ferromagnetic fixed layer structure (AFFP) and the antiparallel coupling ferromagnetic fixed layer structure (AFAPP) containing antiferromagnetic material can only be used as the farthest structure from the substrate in the fixed layer. When they are combined with the aforementioned ferromagnetic fixed layer structure or antiparallel coupling ferromagnetic fixed layer structure, the adjacent parts such as the oxide coupling layer can be shared. In addition, when adjacent to the free layer, the tunneling layer magnesium oxide can be shared as the oxide coupling layer.

[0018] The application provides a magnetic tunnel junction for a magnetic storage chip and a magnetic sensing chip.

[0019] (1.1) from the substrate to the far from the ferromagnetic film structure as a free layer, magnesium oxide film as a tunnel layer, and the ferromagnetic film structure as a fixed layer; and the fixed layer is composed of a first ferromagnetic film structure, an antiparallel coupling layer, a second ferromagnetic film structure, a first oxide coupling layer, a third ferromagnetic film structure, a magnesium oxide film.

[0020] (1.2) from the substrate to the far from the ferromagnetic film structure as a free layer, magnesium oxide film as a tunnel layer, and the ferromagnetic film structure as a fixed layer; and the fixed layer is composed of a first ferromagnetic film structure, an antiparallel coupling layer, a second ferromagnetic film structure, a first oxide coupling layer, a third ferromagnetic film structure, a second oxide coupling layer, a fourth ferromagnetic film structure, and a magnesium oxide film.

[0021] (1.3) from the substrate to the far from the ferromagnetic film structure as a free layer, magnesium oxide film as a tunnel layer, and the ferromagnetic film structure as a fixed layer; and the fixed layer is composed of a first ferromagnetic film structure, a first oxide coupling layer, a second ferromagnetic film structure, an antiparallel coupling layer, a third ferromagnetic film structure, a second oxide coupling layer, a fourth ferromagnetic film structure, and a magnesium oxide film.

[0022] (1.4) from the substrate to the far from the ferromagnetic film structure as a free layer, magnesium oxide film as a tunnel layer, and the ferromagnetic film structure as a fixed layer; and the fixed layer is composed of a first ferromagnetic film structure, a first oxide coupling layer, a second ferromagnetic film structure, an antiparallel coupling layer, a third ferromagnetic film structure, a second oxide coupling layer, a fourth ferromagnetic film structure, a third oxide coupling layer, a fifth ferromagnetic film structure, and a magnesium oxide film.

[0023] (1.5) from the substrate to the far from the ferromagnetic film structure as a free layer, magnesium oxide film as a tunnel layer, and the ferromagnetic film structure as a fixed layer; and the fixed layer is composed of a first ferromagnetic film structure, a first antiparallel coupling layer, a second ferromagnetic film structure, a first oxide coupling layer, a third ferromagnetic film structure, a second antiparallel coupling layer, a fourth ferromagnetic film structure, and a magnesium oxide film.

[0024] (1.6) The structure of the magnetic tunnel junction device from the substrate to the far end is composed of a ferromagnetic film structure as a free layer, a magnesium oxide film as a tunnel layer, and a ferromagnetic film structure as a fixed layer; and the fixed layer is composed of a first ferromagnetic film structure, a first anti-parallel coupling layer, a second ferromagnetic film structure, a first oxide coupling layer, a third ferromagnetic film structure, a second anti-parallel coupling layer, a fourth ferromagnetic film structure, and an anti-ferromagnetic film structure.

[0025] (1.7) The structure of the magnetic tunnel junction device from the substrate to the far end is composed of a ferromagnetic film structure as a free layer, a magnesium oxide film as a tunnel layer, and a ferromagnetic film structure as a fixed layer; and the fixed layer is composed of a first ferromagnetic film structure, a first oxide coupling layer, a second ferromagnetic film structure, an anti-parallel coupling layer, a third ferromagnetic film structure, a second oxide coupling layer, a fourth ferromagnetic film structure, and an anti-ferromagnetic film structure.

[0026] The following is a supplementary explanation: Experimental and simulation results of the magnetic coercivity of the upper fixed layer of the above-mentioned seven kinds of structure magnetic tunnel junction devices and the characteristics of the coupling magnetic field of the free layer show that they can be used in magnetic tunnel junctions, and are expected to reduce the information writing energy consumption of the magnetic tunnel junction, improve the durability of the magnetic tunnel junction, and have a feasible manufacturing process.

[0027] According to the present application, a magnetic tunnel junction for a magnetic storage chip and a magnetic sensing chip is provided, wherein the anti-ferromagnetic film structure contains a platinum-iridium alloy anti-ferromagnet and / or an iridium alloy anti-ferromagnet; the ferromagnetic film structure is an alloy containing iron and boron; the anti-parallel coupling layer material is metal ruthenium or metal iridium; the oxide coupling layer is magnesium oxide containing any one of iron and cobalt plus boron, iron oxide, and any one of an oxide containing iron and cobalt; and the thickness of the oxide coupling layer is greater than that of the tunnel layer.

[0028] The following is a supplementary explanation: The anti-ferromagnetic film structure contains at least any one of a platinum-iridium alloy or an iridium alloy anti-ferromagnet, and can also contain both alloys; in addition, an anti-ferromagnetic film structure formed by some non-magnetic film and a platinum-iridium alloy or an iridium alloy can also be used in the anti-ferromagnetic film structure. Current experiments and simulations show that the oxide coupling layer is mainly formed by adding ferromagnetic materials iron and cobalt and boron to magnesium oxide, but iron oxide and iron-cobalt oxide or their combination can also achieve good parallel coupling capability, i.e., the spin direction of the ferromagnetic film structure at both ends is parallel.

[0029] In another aspect, the present application also provides a manufacturing method of a magnetic storage chip and a magnetic sensing chip based on the magnetic tunnel junction for a magnetic storage chip and a magnetic sensing chip, comprising the following steps:

[0030] (2.1) performing the preparation of the magnetic storage chip and the peripheral circuit of the magnetic sensing chip on the substrate;

[0031] (2.2) performing the preparation of the lower part of the free layer of the magnetic tunnel junction on the metal connection layer of the peripheral circuit;

[0032] (2.3) performing the preparation of the ferromagnetic film structure serving as the free layer;

[0033] (2.4) performing the preparation of the MgO film of the tunneling layer;

[0034] (2.5) performing the preparation of the fixed layer;

[0035] (2.6) patterning the film to form the device of the magnetic storage chip and the magnetic sensing chip;

[0036] (2.7) performing the connection and packaging of the device to form the chip.

[0037] The following is a supplementary explanation of the above: the lower part of the free layer in the above (2.2) corresponds to the magnetic tunnel junction of the double fixed layer structure of the magnetic transport moment, mainly referring to the lower fixed layer. For the magnetic track moment magnetic tunnel junction, the lower part of the free layer refers to the spin Hall track generating the spin polarization.

[0038] The effect of the present application is to realize the growth of the fixed layer above the free layer of the MTJ which cannot be realized by the conventional technology; the grown fixed layer has a great coercivity and reduces the exchange coupling magnetic field generated by the free layer. The present application can realize the double fixed layer MTJ with the fixed layer at both ends of the free layer, so the fixed layer and the free layer can both use the ferromagnetic material with high spin polarization rate. Thus the current when the spin direction of the free layer relative to the lower fixed layer is parallel to anti-parallel or anti-parallel to parallel can be reduced, and the durability of the tunneling layer MgO is increased while reducing the information writing energy consumption.

[0039] In addition, the structure of the present application can also be used for the MTJ based on the SOT writing mode or the mixed writing mode of SOT and STT, and the magnetic sensor including the hard disk head based on the MTJ. BRIEF DESCRIPTION OF DRAWINGS

[0040] Fig. 1 is one of the embodiments of the present application, which is the basic structure of the MTJ device of the fixed layer (Pin) of the present application on the upper part of the free layer. Among them, the anti-parallel coupling ferromagnetic fixed layer structure (APP) is close to the free layer (FL), and the ferromagnetic fixed layer structure (FP) adjacent to the upper part thereof constitutes the fixed layer Pin on the upper part of the free layer.

[0041] Figure 2 is one embodiment of the present application, which is a basic structure of the MTJ device of the fixed layer on the upper part of the free layer. In this embodiment, the APP is adjacent to the free layer FL, and the two FP adjacent to the upper part of the free layer FL form the fixed layer Pin on the upper part of the free layer.

[0042] Figure 3 is one embodiment of the present application, which is a basic structure of the MTJ device of the fixed layer on the upper part of the free layer. In this embodiment, the FP is adjacent to the free layer FL, and the APP adjacent to the upper part of the free layer FL and the FP further above form the fixed layer Pin on the upper part of the free layer.

[0043] Figure 4 is one embodiment of the present application, which is a basic structure of the MTJ device of the fixed layer on the upper part of the free layer. In this embodiment, one FP is added on the upper part of Figure 3 to form the fixed layer Pin on the upper part of the free layer.

[0044] Figure 5 is one embodiment of the present application, which is a basic structure of the MTJ device of the fixed layer on the upper part of the free layer. In this embodiment, the APP is adjacent to the free layer FL, and the other APP adjacent to the upper part of the free layer FL form the fixed layer Pin on the upper part of the free layer.

[0045] Figure 6 is one embodiment of the present application, which is a basic structure of the MTJ device of the fixed layer on the upper part of the free layer. In this embodiment, the APP is adjacent to the free layer FL, and the anti-parallel coupling ferromagnetic fixed layer (AFAPP) containing the anti-ferromagnetic layer adjacent to the upper part of the free layer FL form the fixed layer Pin on the upper part of the free layer.

[0046] Figure 7 is one embodiment of the present application, which is the fixed layer of five structures (a, b, c, d, e) formed by the combination of FP and AFP. In this embodiment, the upward and downward arrows represent the direction of spin or magnetization.

[0047] Figure 8 (A) is the coercivity of the five combinations in Figure 7 prepared in a certain way; Figure 8 (B) is a schematic diagram of the structure of the fixed layer prepared on the upper part of the free layer according to the five ways and the schematic diagram of the exchange coupling hysteresis loop generated by the fixed layer on the free layer; Figure 8 (C) is a graph of the measured exchange coupling magnetic field and the device diameter of the five structures.

[0048] Figure 9 is one embodiment of the present application, which is the fixed layer of four structures (f, g, h, i) formed by the combination of FP, AFFP and APP. In this embodiment, the upward and downward arrows represent the direction of spin or magnetization.

[0049] Figure 10 (A) is the coercivity of the four combinations in Figure 9 prepared in a certain way; Figure 10 (B) is a graph of the measured exchange coupling magnetic field and the device diameter of the four structures.

[0050] Figure 11 is one of the embodiments of the present application, which is different from Figure 3 in that the FP on the upper part is replaced by an anti-parallel coupling ferromagnetic fixed layer (AFFP) containing an anti-ferromagnetic layer.

[0051] Reference signs:

[0052] 1: Free layer ferromagnetic thin film structure;

[0053] 2: Tunneling layer MgO thin film;

[0054] 1X (X = 1, 2, 3, 4…): ferromagnetic thin film structure, a component of FP or AFFP;

[0055] 2X (X = 1, 2, 3, 4…): ferromagnetic thin film structure, a component of APP or AFAPP;

[0056] 3X (X = 1, 2, 3, 4…): anti-parallel coupling layer, part of the figure is represented as APC;

[0057] 4X (X = 1, 2, 3, 4…): oxide coupling layer, part of the figure is represented as Oxide or Mid Oxide;

[0058] 5: Magnesium oxide thin film layer;

[0059] 6: Anti-ferromagnetic magnetic thin film structure. DETAILED DESCRIPTION

[0060] The present application is described below with reference to the accompanying drawings and examples of embodiments. Best Mode for Carrying Out the Invention

[0061] The best mode for carrying out the present application is entered here.

[0062] Example 1:

[0063] The devices of the six structures of Figures 1 to 6 are composed of four structures of ferromagnetic fixed layer structure (FP), anti-parallel coupling ferromagnetic fixed layer structure (APP), ferromagnetic fixed layer structure containing an anti-ferromagnetic layer (AFFP), and anti-parallel coupling ferromagnetic fixed layer structure containing an anti-ferromagnetic layer (AFAPP), and when combined, any two structures are connected through a shared oxide coupling layer, and a tunneling layer can also be applied.

[0064] Example 2:

[0065] Figure 7 proposes five structures of fixed layer, (a), (b), (c), (d), (e). (a) and (b) are basic structures. (a) is a structure of two oxide coupling layers (usually MgO) sandwiching a ferromagnetic thin film structure, which is called ferromagnetic fixed layer structure (FP). (b) is a structure of two oxide coupling layers (usually MgO) sandwiching a ferromagnetic thin film structure with anti-parallel coupling. The anti-parallel coupling layer (APC) is usually a metal thin film layer of ruthenium or iridium with a thickness of about 0.1 to 1.5 nm, which is called anti-parallel coupling ferromagnetic fixed layer structure (APP). The ferromagnetic thin film structure for FP is usually an alloy of iron and boron, an alloy of iron, cobalt and boron, and the above alloy with the addition of rhenium and tungsten, with a total thickness of about 1 to 4 nm. The ferromagnetic thin film structure for APP is usually an alloy of iron and boron, an alloy of iron, cobalt and boron, and the above alloy with the addition of rhenium and tungsten, with a thickness of about 0.5 to 4 nm. The anti-parallel coupling layer makes the spins of the two ferromagnetic thin film structures of APP anti-parallel.

[0066] Generally, the coercivity of the free layer of the MTJ device is about 1000 Oe to 2000 Oe, and the fixed layer needs to be more than 4000 Oe. Figure 8 (A) is the coercivity of the fixed layer of the five MTJ devices in Figure 7 when the diameter is 30 nm. It can be seen that the coercivity of FP (a) alone and APP (b) alone is less than 3000 Oe, which is not suitable for a fixed layer. The coercivity of the fixed layer of (c) two FP combinations, (d) APP and FP combinations, and (e) APP and two FP combinations above is more than 4000 Oe when the device diameter is 30 nm, which can be used as a fixed layer.

[0067] Another important characteristic of the fixed layer is the coupling magnetic field (H bias ) generated by the fixed layer to the free layer as shown in Figure 8 (B). Figure 8 (C) is a graph of the coupling magnetic field generated by the five fixed layer structures in Figure 7 to the free layer and the diameter of the magnetic tunnel junction. It is found that the coupling magnetic field of the fixed layer to the free layer increases as the diameter decreases for all devices. For the three structures (c), (d), and (e) whose coercivity meets the fixed layer, the H bias of (c) is 2000 Oe when the device diameter is 20 nm, which is greater than the coercivity of the free layer of (c), which will make the free layer unable to record the "0" and "1" states, so (c) cannot be used as a fixed layer. The H bias of (d) and (e) is -59 Oe and -401 Oe, respectively, which is smaller than the coercivity of the free layer and can be easily adjusted to 0. Both (d) and (e) can be used as a fixed layer.

[0068] Example 3:

[0069] Figure 9 shows other combinations of FP and APP. (f) is a structure in which APP is formed on FP, and then FP is formed on the APP. (g) is a structure in which APP is formed on FP, and then two FP are formed on the APP. (h) is a structure in which two APP are stacked. (i) is a structure in which an anti-ferromagnetic fixed layer structure (AFAPP) containing an anti-ferromagnetic layer is stacked on APP. As described above, the AFAPP is actually a structure in which the oxide coupling layer on the upper layer of the APP is replaced by an anti-ferromagnetic thin film structure. The anti-ferromagnetic thin film structure of the AFAPP is usually a MnPt alloy or MnIr alloy anti-ferromagnetic thin film structure. As in Figure 7, the oxide coupling layer in the structure of Figure 9 is a Mid Oxide structure, which functions to make the spin directions of the ferromagnetic thin film structures at both ends thereof parallel, thereby integrating the multi-layer ferromagnetic thin film structure and increasing the coercive force.

[0070] Figure 10(A) is a graph showing the coercive force of the four fixed layers of (f) to (i) when the diameter is 30 nm, and the numbers are all greater than 4000 Oe, i.e., all can be used as fixed layers from the aspect of the coercive force. Figure 10(B) is a graph showing the relationship between the coupling magnetic field of the four fixed layer structures on the free layer and the diameter of the magnetic tunnel junction. As in Figure 8(C), all the devices have the coupling magnetic field of the fixed layer on the free layer increase as the diameter decreases. The H bias respectively, which is smaller than the coercive force of the free layer and can be easily adjusted to 0, so the four structures of (f) to (i) can all be used as fixed layers. The (i) structure is actually a structure in which the uppermost layer of (h) is replaced by an anti-ferromagnetic thin film MnPt instead of the oxide coupling layer. The use of MnPt can more stably form the up-down alternating magnetization in the structure of (i) and (h), and improve the performance of the device. The (f) structure also uses an anti-ferromagnetic thin film structure on the uppermost layer for the same reason, i.e., to form an anti-ferromagnetic fixed layer of anti-parallel coupling ferromagnetic (AFFP), i.e., the structure of Figure 11.

[0071] The above examples only express certain embodiments of the present application, are described in more detail, but should not be understood as limiting the scope of the patent. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application. Therefore, the scope of protection of the present application should be subject to the appended claims.

Claims

1. A magnetic tunnel junction for a magnetic storage chip and a magnetic sensing chip, comprising: The magnetic tunnel junction is composed of a ferromagnetic thin film structure serving as a free layer, a magnesium oxide thin film serving as a tunnel layer, and a ferromagnetic thin film structure serving as a fixed layer from the substrate in the order from near to far; The fixed layer ferromagnetic thin film structure is composed of a ferromagnetic fixed layer structure of an oxide coupling layer, a ferromagnetic thin film structure, and an oxide coupling layer, and a antiparallel coupling ferromagnetic fixed layer structure of an oxide coupling layer, a ferromagnetic thin film structure, an antiparallel coupling layer, a ferromagnetic thin film structure, and an oxide coupling layer from the substrate in the order from near to far, and both structures contain at least one and any one structure contains at least one structure combination.

2. The magnetic tunnel junction for magnetic storage chip and magnetic sensing chip of claim 1, wherein, The fixed layer is composed of a ferromagnetic fixed layer structure containing an antiferromagnet of an oxide coupling layer, a ferromagnetic thin film structure, and an antiferromagnetic thin film structure from the substrate in the order from near to far, and an antiparallel coupling ferromagnetic fixed layer structure containing an antiferromagnet of an oxide coupling layer, a ferromagnetic thin film structure, an antiparallel coupling layer, a ferromagnetic thin film structure, and an antiferromagnetic thin film structure from the substrate in the order from near to far at the end farthest from the substrate.

3. The magnetic tunnel junction for a magnetic storage chip and a magnetic sensing chip of claim 2, wherein, The magnetic tunnel junction is composed of a ferromagnetic thin film structure serving as a free layer, a magnesium oxide thin film serving as a tunnel layer, and a ferromagnetic thin film structure serving as a fixed layer from the substrate in the order from near to far; and the fixed layer is composed of a first ferromagnetic thin film structure, an antiparallel coupling layer, a second ferromagnetic thin film structure, a first oxide coupling layer, a third ferromagnetic thin film structure, and a magnesium oxide thin film.

4. The magnetic tunnel junction for magnetic storage chip and magnetic sensing chip of claim 2, wherein, The magnetic tunnel junction is composed of a ferromagnetic thin film structure serving as a free layer, a magnesium oxide thin film serving as a tunnel layer, and a ferromagnetic thin film structure serving as a fixed layer from the substrate in the order from near to far; and the fixed layer is composed of a first ferromagnetic thin film structure, an antiparallel coupling layer, a second ferromagnetic thin film structure, a first oxide coupling layer, a third ferromagnetic thin film structure, and a second oxide coupling layer.

5. The magnetic tunnel junction for magnetic storage chip and magnetic sensing chip of claim 2, wherein, The magnetic tunnel junction is composed of a ferromagnetic thin film structure serving as a free layer, a magnesium oxide thin film serving as a tunnel layer, and a ferromagnetic thin film structure serving as a fixed layer from the substrate in the order from near to far; and the fixed layer is composed of a first ferromagnetic thin film structure, a first oxide coupling layer, a second ferromagnetic thin film structure, an antiparallel coupling layer, a third ferromagnetic thin film structure, a second oxide coupling layer, a fourth ferromagnetic thin film structure, and a magnesium oxide thin film.

6. The magnetic tunnel junction for magnetic storage chip and magnetic sensing chip of claim 2, wherein, The magnetic tunnel junction is composed of a ferromagnetic thin film structure serving as a free layer, a magnesium oxide thin film serving as a tunnel layer, and a ferromagnetic thin film structure serving as a fixed layer from the substrate in the order from near to far; and the fixed layer is composed of a first ferromagnetic thin film structure, a first oxide coupling layer, a second ferromagnetic thin film structure, an antiparallel coupling layer, a third ferromagnetic thin film structure, a second oxide coupling layer, a fourth ferromagnetic thin film structure, a third oxide coupling layer, a fifth ferromagnetic thin film structure, and a magnesium oxide thin film.

7. The magnetic tunnel junction for magnetic storage chip and magnetic sensing chip of claim 2, wherein, The free layer is made of a ferromagnetic film structure, the MgO film is a tunneling layer, and the fixed layer is made of a ferromagnetic film structure; and the fixed layer is made of a first ferromagnetic film structure, a first anti-parallel coupling layer, a second ferromagnetic film structure, a first oxide coupling layer, a third ferromagnetic film structure, a second anti-parallel coupling layer, a fourth ferromagnetic film structure, and an anti-ferromagnetic film structure.

8. The magnetic tunnel junction for magnetic storage chip and magnetic sensing chip of claim 2, wherein, The free layer is made of a ferromagnetic film structure, the MgO film is a tunneling layer, and the fixed layer is made of a ferromagnetic film structure; and the fixed layer is made of a first ferromagnetic film structure, a first anti-parallel coupling layer, a second ferromagnetic film structure, a first oxide coupling layer, a third ferromagnetic film structure, a second anti-parallel coupling layer, a fourth ferromagnetic film structure, and an anti-ferromagnetic film structure.

9. The magnetic tunnel junction for magnetic storage chip and magnetic sensing chip of claim 2, wherein, The free layer is made of a ferromagnetic film structure, the MgO film is a tunneling layer, and the fixed layer is made of a ferromagnetic film structure; and the fixed layer is made of a first ferromagnetic film structure, a first anti-parallel coupling layer, a second ferromagnetic film structure, a first oxide coupling layer, a third ferromagnetic film structure, a second anti-parallel coupling layer, a fourth ferromagnetic film structure, and an anti-ferromagnetic film structure.

10. The magnetic tunnel junction for a magnetic storage chip and a magnetic sensing chip according to any one of claims 2, 8 and 9, wherein, The anti-ferromagnetic film structure contains PtIr alloy anti-ferromagnetic and / or IrPt alloy anti-ferromagnetic; the ferromagnetic film structure is an alloy containing iron and boron; the anti-parallel coupling layer material is metal ruthenium or metal iridium; the oxide coupling layer is MgO containing any one of iron and cobalt plus boron, iron oxide, and oxide containing iron and cobalt; and the oxide coupling layer has a thickness greater than the tunneling layer.

11. A manufacturing method of a magnetic storage chip and a magnetic sensing chip for a magnetic tunnel junction of the magnetic storage chip and the magnetic sensing chip according to any one of claims 1 to 9, characterized by, The method comprises the following steps: Preparation of magnetic storage chip and magnetic sensor chip peripheral circuit on a substrate; Preparation of a magnetic tunnel junction free layer below a metal connection layer of the peripheral circuit; Preparation of a ferromagnetic film structure as a free layer; Preparation of a MgO film as a tunneling layer; Preparation of the fixed layer; Patterning of the film to form a device of the magnetic storage chip and the magnetic sensor chip; Connection and packaging of the device to form a chip.

Images