201106351 六、發明說明： 【發明所屬之技術領域】 本發明係有關於一種磁性穿隧接面元件、用於磁性穿 隧接面元件之自由層結構及包括該元件之磁性記憶體，尤 指一種可降低翻轉臨界電流密度之磁性穿隧接面元件及包 括該元件之磁性記憶體。 【先前技術】 磁性隨機存取記憶體（Magnetic Random Access • Memory，MRAM)為一種非揮發性記憶體’其係利用磁阻特 性儲存紀錄資料，具有低耗能、快速存取以及無限制讀取 次數等優點’即有可能成為未來記憶體市場的主要趨勢。 而磁性穿 P遂接面（Magnetic Tunnel Junction，MTJ)為磁 性隨機存取記憶體的主要結構之一，磁性隨機存取記憶體 係由複數個具有磁性穿隧接面元件之磁性記憶單元所組 成。請參閱第1圖，其係為一具有固定層11、穿隧絕緣層 φ 12、自由層13之依序堆疊的結構，其中固定層11及自由 層13係包括磁性材料。針對磁性穿隨接面元件而言，係利 用經過垂直相交的字元線與位元線之電流所產生的磁場， 來改變磁性穿隧接面元件中的磁化方向，而藉由固定層11 與自由層13之磁化方向所導致的磁阻差異，通常是固定固 定層11而翻轉自由層13之磁化方向，來達成高磁阻狀態 與低磁組狀態，換言之，可藉由判定緊鄰穿隧絕緣層12 之固定層11與自由層13之磁化向量為平行狀態或反平行 狀態，而決定記憶狀態為或“1”。 Π1351 201106351 然而，隨著磁性隨機存取記憶體的尺寸愈益縮小，磁 性穿隧接面元件的集積密度亦隨之提高，便產生邊際效應 (edge curling effect)而造成讀寫上的錯誤。習知技術針對此 問題發展出“Toggle(觸發）MRAM”，其係利用通過分階段 的電流來寫入數據，此種寫入方式需兩條導線通入電流的 時間上有差異才能將磁矩翻轉’卻會使得通入的電流有所 增大。此外，由於記憶體尺寸微小化會使得磁性穿隧接面 元件中的自由層之矯頑力提高，如此需增加電流供應量才 得以克服矯頑力而翻轉自由層的磁矩，而在記憶單位集積 密度愈來愈大的情況下，導入大電流勢必導致記憶體中各 個記憶早位的彼此影響’使得磁區不穩定。再著5習知技 術在磁性穿隧接面元件邊界會產生渦流效應，亦即在磁性 穿隧接面元件的邊界磁區呈現一渦流狀，致使即便提供外 加磁場依然無法翻轉磁區，繼而影響磁阻變化率。 综上所述，如何提供一種可降低翻轉臨界電流密度之 磁性穿隧接面結構、磁性穿隧接面元件及磁性記憶單元， 可解決由於磁性隨機存取記憶體的尺寸縮小所引起的渦流 效應，除可提高磁性記憶單位的磁區穩定性，更可提高磁 組變化率，遂成為目前亟待解決的課題。 【發明内容】 鑒於上述習知技術之缺點，本發明提供一種磁性穿隧 接面元件、用於磁性穿隧接面元件之自由層結構以及包括 該元件之磁性記憶體，可降低臨界翻轉電流密度、增加磁 區穩定以及提高磁阻變化率。 4 3]1351 201106351 ‘ 本《明之磁性穿隨接面元件，係包括：固定層；形成 於層上之穿隨層；以及形成於該穿隨層上之自由 層，俾使該穿隨層夾置於該固定層與自由層之間，且該自 由層，括依序堆疊之第一磁性薄膜、非磁性薄膜以及第二 磁I·生薄膜以形成垂直異相性之反鐵磁性結構，其中，該非 磁^膜具有一預定厚度，且該第一磁性薄膜與該第二磁 性薄膜之磁化方向為反平行態耦合。 _ 貫施例中，本發明發現非磁性賴之厚度係呈現 反=仃祕合之重要因素，具體而言，該自由層中之非磁 性缚膜之厚度係大於或等於24埃，且以大於24埃之厚度 為佳。201106351 VI. Description of the Invention: [Technical Field] The present invention relates to a magnetic tunneling junction element, a free layer structure for a magnetic tunneling junction element, and a magnetic memory including the same, especially a magnetic memory A magnetic tunneling junction element that reverses the critical current density and a magnetic memory including the element. [Prior Art] Magnetic Random Access Memory (MRAM) is a non-volatile memory that uses magnetoresistive characteristics to store recorded data with low power consumption, fast access, and unlimited reading. The advantages of the number of times, that is, it is likely to become the main trend in the future memory market. The magnetic tunneling junction (MTJ) is one of the main structures of the magnetic random access memory. The magnetic random access memory system is composed of a plurality of magnetic memory cells having magnetic tunneling junction elements. Referring to Fig. 1, there is shown a structure in which a fixed layer 11, a tunneling insulating layer φ 12, and a free layer 13 are sequentially stacked, wherein the fixed layer 11 and the free layer 13 comprise magnetic materials. For the magnetic wear-fed surface element, the magnetic field generated by the current passing through the vertically intersecting word line and the bit line is used to change the magnetization direction in the magnetic tunneling junction element, and by fixing the layer 11 with The difference in magnetoresistance caused by the magnetization direction of the free layer 13 is usually the fixed pinned layer 11 and the magnetization direction of the free layer 13 is reversed to achieve a high magnetoresistance state and a low magnetic group state, in other words, by determining the adjacent tunneling insulation. The magnetization vector of the fixed layer 11 of the layer 12 and the free layer 13 is in a parallel state or an anti-parallel state, and the memory state is determined to be "1". Π 1351 201106351 However, as the size of magnetic random access memory shrinks, the density of magnetic tunneling junction elements increases, resulting in an edge curling effect that causes errors in reading and writing. The prior art has developed a "Toggle" MRAM for this problem, which uses a phased current to write data. This type of writing requires a difference in the time between the two wires to pass the current. Flipping 'will increase the current flowing through. In addition, since the memory size is miniaturized, the coercive force of the free layer in the magnetic tunneling junction element is increased, so that the current supply amount needs to be increased to overcome the coercive force and flip the magnetic moment of the free layer, while in the memory unit. In the case where the accumulation density is getting larger and larger, the introduction of a large current tends to cause the mutual influence of each memory in the memory to make the magnetic region unstable. Further, the conventional technique generates an eddy current effect at the boundary of the magnetic tunneling junction element, that is, a eddy current appears in the boundary magnetic region of the magnetic tunneling junction element, so that even if an external magnetic field is provided, the magnetic domain cannot be reversed, which in turn affects Magnetoresistance change rate. In summary, how to provide a magnetic tunneling junction structure, a magnetic tunneling junction component and a magnetic memory cell capable of reducing the inversion critical current density can solve the eddy current effect caused by the size reduction of the magnetic random access memory In addition to improving the magnetic zone stability of the magnetic memory unit, the magnetic group change rate can be improved, which has become an urgent problem to be solved. SUMMARY OF THE INVENTION In view of the above disadvantages of the prior art, the present invention provides a magnetic tunneling junction element, a free layer structure for a magnetic tunneling junction element, and a magnetic memory including the element, which can reduce the critical inversion current density. Increase magnetic zone stability and increase the rate of change of magnetoresistance. 4 3] 1351 201106351 'The magnetic magnetic wear-receiving surface element of the present invention includes: a fixed layer; a wear-through layer formed on the layer; and a free layer formed on the wear-through layer, so that the wear-through layer clip And disposed between the fixed layer and the free layer, and the free layer includes a first magnetic film, a non-magnetic film, and a second magnetic film that are sequentially stacked to form a vertical heterogeneous antiferromagnetic structure, wherein The non-magnetic film has a predetermined thickness, and the magnetization directions of the first magnetic film and the second magnetic film are coupled in an anti-parallel state. In the present embodiment, the present invention finds that the thickness of the non-magnetic layer is an important factor of the anti-仃 ,, in particular, the thickness of the non-magnetic film in the free layer is greater than or equal to 24 angstroms, and is greater than The thickness of 24 angstroms is better.
於本I月中，主要係使自由層形成垂直異相性之反鐵 、ί、。構方、具脰貝施上，該第—磁性薄膜及第二磁性薄 膜係獨立選自鐵磁性材料，磁性薄膜及第二磁性薄 媒可為相同或不同材料者’且以相同材料者為佳。於一且 ，實施例中，該自由層之第一磁性薄膜包括選自 之-種或多種元素’而該自由層之第二雜薄膜可獨 ^包括選自C〇、Nl或Fe之-種或多種元素，由上可知， =弟一磁性薄膜及第二磁性薄料可由單—元素或多種元 =構成。而該自由層之非魏_係選自白金族之一種 ΐ夕種元素’本發料料置於第―磁㈣膜及第二磁性 賴間之非賴性金屬使得魏料被翻轉。於另—呈卿 貫施例中，該自由層之非磁性薄膜係選自p^pd。“In the first month of this month, the main layer is the anti-iron, ί, which forms the vertical heterogeneity of the free layer. The first magnetic film and the second magnetic film are independently selected from the group consisting of ferromagnetic materials, and the magnetic film and the second magnetic thin film may be the same or different materials, and the same material is preferred. . In an embodiment, the first magnetic film of the free layer comprises one or more elements selected from the group consisting of 'the element or the plurality of elements', and the second impurity film of the free layer may comprise a species selected from the group consisting of C〇, Nl or Fe. Or a plurality of elements, as can be seen from the above, the magnetic film and the second magnetic thin material may be composed of a single element or a plurality of elements. The non-wei of the free layer is selected from the group of the platinum group. The non-dependent metal placed between the first magnetic (four) film and the second magnetic material causes the material to be inverted. In another embodiment, the non-magnetic film of the free layer is selected from p^pd. "
本發明復提供-種磁性記憶體，係包括：第H 1Π351 1 201106351 丨. 形成於該第一電極上的本發明之磁性穿隨接面元件以及位 於該磁性穿隧接面元件上之第二電極，俾使該磁性穿隨接 面元件夾置於該第一電極與第二電極之間。 於另一態樣中，本發明復提出—種用於磁性穿隨接面 =牛之自由層結構，包括依序堆疊之第—磁㈣膜、非磁 ^專^以及第二磁性薄膜以形成垂直異相性之反鐵磁性結 :中夕非磁性薄膜具有一預定厚度，俾使該 p 逆接面兀件呈現反平行態耦合。 反平本發賴現細㈣叙厚度係呈現 素’具體而言，該自由層或自由層 之非魏薄敎狀厚度係大於或等於 大於24埃之厚度為佳。 人 構。本發明主要係使自由層形成垂直異向之反鐵磁性結 獨立、ί、自具肢貫施上，該第—磁性f膜及第二磁性薄膜係 鐵磁性材料’且第-磁性薄膜及第二磁性薄膜； =或不同材料者，且以相同材料者為佳。於一具體實 =中^由層結構之第一磁性薄膜包括選自心 獨立地包素，而該自由層結構之第二磁性薄膜可 知，：邮之一種或多種元素，由上可 種元ΐ戶 性薄膜及第二磁性薄膜皆可由單一元素或多 族之—種或夕、而该自由層結構之非磁性薄膜係選自白金 第二磁性薄=兀素，本發明透過夹置於第一磁性薄膜及 蝴之非鐵磁性金屬使得磁矩容易被翻轉。 ⑴35] 6 201106351 ‘ ' 她於習知技術’本發明將垂直異向性之反鐵磁性層 應用於磁性穿隨接面元件，可使其形成較薄之自由層。此 外，、自由層中的非磁性薄膜因具有一預定厚度，而使得第 人磁性層與弟二磁性薄膜兩者的磁化方向為反平行態輕 ^ ’詳言之’.於兩磁性薄膜層之間夾置有-厚度大於24 :之非磁性薄膜，因而可有效降低翻轉電流，提高磁區穩 定性，並可提高磁阻變化率。 “ 【實施方式】 以下係藉由特定的具體實施例說明本發明之實施方 悉此技術之人士可由本說明書所揭示之内容輕易地 毛明之其他優點與功效。本發明亦可藉由其他不同 =體實施例加以施料助。本說明書中的各項細節亦 ^不r親點與應用’在不悖離本發明之精神下進 種修斜與變更。 以下之實施例係進—步詳細說明本發明之觀點，但並 非以任何觀點限制本發明之範疇。 =残第2 ® ’其係顯示本發明之磁性穿祕面元件 心例之基本結構示意圖。如第2圖所* =元件2係包括依序為固定層21、穿隨層”以及= 層23之堆疊結構。 固^層^ ’其材料包括具有垂直異向性及反鐵磁性 身又而5 ’可為如Co ' Fe或Ni耸料r并ω I 或Pd等白4寻鐵磁性材料與如Pt 办&知材抖所組成之反鐵磁性多層結構。 穿隨層22,係形成於固定層21上，可為如峋〇' 1]]35] 7 201106351 AI2O3、TiN或TaN等絕緣材料所組成。 如第2圖所示，自由層23係形成於穿隧層22上，係 包括依序為第一磁性薄膜231、非磁性薄膜232以及第二 磁性薄膜233之堆疊結構，且第一磁性薄膜231與第二磁 性薄膜233之磁化方向為反鐵磁耦合者。此外，自由層23 所包括之材料係具有垂直異向性或使得自由層23呈現垂 直異向性，舉例而言，第一磁性薄膜231與第二磁性薄膜 233係獨立選自鐵磁性材料，如Co、Fe或Ni，而非磁性 薄膜232係選自白金族之一種或多種元素，因而自由層23 為如 Co/Pt/Co、Co/Pd/Co、Fe/Pt/Fe 或 Fe/Pd/Fe 之反鐵磁 性結構。於本實施例中，自由層23之非磁性薄膜232的厚 度之較佳態樣係大於24埃，除此之外，本實施例並未限定 其他各層之厚度，例如第一磁性薄膜231與第二磁性薄膜 233亦可為不同厚度且不同的鐵磁性材料。 接著，請參閱第3圖，其係顯示本發明之磁性記憶體 之一實施例之基本結構示意圖。如第3圖所示，磁性穿隧 接面元件3係包括依序為第一電極層24、固定層2卜穿隧 層22、第一磁性薄膜231、非磁性薄膜232、第二磁性薄 膜233以及第二電極層24’之堆疊結構。在此須說明的是， 從固定層21至第二磁性薄膜233即為本發明之磁性穿隧接 面元件2，其各層材料與特性皆與如第2圖所圖示之實施 例相同，例如非磁性薄膜232的厚度需大於或等於24埃， 而第一磁性薄膜231與第二磁性薄膜233之磁化方向呈現 反鐵磁耦合。此外，於一實施例中，可於第一磁性薄膜231 8 Π135] 201106351 .與穿隧層22之間以及第二磁性薄膜233與第二電極層24, 之間’分別設置第一非磁性過渡金屬層及第二非磁性過渡 金屬層（未予以圖示），而以pt或Pd作為此非磁性過渡金 屬層的垂直異向性較佳。 因此’藉由本發明之磁性穿隧接面元件，俾使自由層 呈現垂直異相性及反鐵磁性以令磁性記憶體之磁矩翻轉電 流密度下降、進而使磁區穩定性增加及磁阻變化率提高。 再者，請參閱第4A圖昱第4D圖，第4A圖至第4C 馨圖係顯示形成於穿隨層上之本發明自由層之外加磁場與磁 矩翻轉之關係圖，其中，矩形點折線顯示外加磁場由正 +400到-400再回到+4〇〇 〇e之磁滯曲線（major loop)，而圓 形點折線顯示局部磁滞曲線（minor loop)，而於第4A圖 中，磁矩值於磁場為大約+50 Oe時下降而於磁場為 +50〜-150 Oe時為持平。另一方面，本實施例之層結構製 備如下。首先以習知半導體薄膜沉積手段於如二氧化石夕之 φ 基板上沉積厚度]5埃的穿隧層MgO，再沉積自由層，即 依序沉積一厚度4埃之Co層、厚度X埃之Pt層以及厚度 4埃之Co層。但在第4A圖所示之實例中，復包括在形成 穿隧層及自由層之後，分別形成兩層作為第一非磁性過渡 金屬層及第二非磁性過渡金屬層之Pt層，是以，第4A圖 係具有厚度 24 埃之非磁性薄膜 SiO2/MgO(15)/Pt(20)/Co(4)/Pt(24)/Co(4)/Pt(6)之堆疊結 構。同樣地，第4B圖及第4C圖所示之結構，分別具有 SiO2/MgO(15)/Pt(20)/Co(4)/Pt(28)/Co(4)/Pt(6) 及 9 111351 201106351The present invention provides a magnetic memory, comprising: H 1Π351 1 201106351 丨. The magnetic wear-fed surface element of the present invention formed on the first electrode and the second on the magnetic tunneling interface element The electrode, the magnetic penetrating surface element is sandwiched between the first electrode and the second electrode. In another aspect, the present invention provides a free layer structure for a magnetic wear-fed surface = a cow, comprising a first-magnetic (four) film, a non-magnetic film, and a second magnetic film stacked in sequence to form The anti-ferromagnetic junction of the vertical heterogeneity: the non-magnetic film of the mid-night has a predetermined thickness, so that the p-reverse surface element exhibits an anti-parallel state coupling. The anti-flatness of the present invention is based on the fact that the thickness of the free layer or the free layer is greater than or equal to the thickness of more than 24 angstroms. Human structure. The invention mainly comprises the step of applying a vertical anisotropic antiferromagnetic junction to the free layer, and applying the same, the first magnetic film and the second magnetic film ferromagnetic material and the first magnetic film and the first Two magnetic films; = or different materials, and the same material is preferred. The first magnetic film of the layer structure comprises a core material selected from the core, and the second magnetic film of the free layer structure is: one or more elements of the mail, from the upper species The household film and the second magnetic film may be composed of a single element or a plurality of groups or a non-magnetic film, and the non-magnetic film of the free layer structure is selected from the group consisting of platinum second magnetic thin = halogen, and the present invention is sandwiched by the first The magnetic film and the non-ferromagnetic metal of the butterfly make the magnetic moment easily reversed. (1) 35] 6 201106351 ‘ 'She is a well-known technique'. The present invention applies a vertical anisotropic antiferromagnetic layer to a magnetic wear-fed surface element to form a thin free layer. In addition, the non-magnetic film in the free layer has a predetermined thickness, so that the magnetization direction of both the first magnetic layer and the second magnetic film is anti-parallel and is lighter than 'detailed'. A non-magnetic film having a thickness greater than 24: is interposed therebetween, thereby effectively reducing the inversion current, improving the stability of the magnetic domain, and increasing the rate of change of magnetoresistance. [Embodiment] The following is a description of specific advantages and functions of the person skilled in the art by the embodiments of the present invention, which can be easily disclosed by the present disclosure. The present invention may also be different by other The embodiments are provided with the aid of the application. The details of the present specification are also in the spirit of the invention, and the modifications and changes are made without departing from the spirit of the invention. The following embodiments are described in detail. The present invention does not limit the scope of the present invention in any way. = Residue 2 ® ' is a schematic diagram showing the basic structure of the magnetic piercing element of the present invention. As shown in Fig. 2 = element 2 The stack structure including the fixed layer 21, the wear-through layer, and the layer 23 is included. The solid layer ^'the material includes a vertical anisotropy and an antiferromagnetic body and the 5' can be a white 4 ferronic magnetic material such as Co 'Fe or Ni rag and r ω I or Pd and such as Pt & The antiferromagnetic multilayer structure composed of the material. The wearing layer 22 is formed on the fixed layer 21 and may be composed of an insulating material such as 峋〇1]]35] 7 201106351 AI2O3, TiN or TaN. As shown in FIG. 2, the free layer 23 is formed on the tunneling layer 22, and includes a stacked structure of the first magnetic film 231, the non-magnetic film 232, and the second magnetic film 233, and the first magnetic film 231. The magnetization direction with the second magnetic film 233 is an antiferromagnetic coupling. In addition, the material included in the free layer 23 has a vertical anisotropy or causes the free layer 23 to exhibit a vertical anisotropy. For example, the first magnetic film 231 and the second magnetic film 233 are independently selected from ferromagnetic materials, such as Co, Fe or Ni, but the magnetic film 232 is selected from one or more elements of the platinum group, and thus the free layer 23 is such as Co/Pt/Co, Co/Pd/Co, Fe/Pt/Fe or Fe/Pd/ The antiferromagnetic structure of Fe. In this embodiment, the thickness of the non-magnetic film 232 of the free layer 23 is preferably greater than 24 angstroms. In addition, the thickness of the other layers is not limited by the embodiment, for example, the first magnetic film 231 and the first The two magnetic films 233 may also be ferromagnetic materials of different thicknesses and differentities. Next, please refer to Fig. 3, which is a schematic view showing the basic structure of an embodiment of the magnetic memory of the present invention. As shown in FIG. 3, the magnetic tunneling interface element 3 includes a first electrode layer 24, a fixed layer 2, a tunneling layer 22, a first magnetic film 231, a non-magnetic film 232, and a second magnetic film 233. And a stacked structure of the second electrode layer 24'. It should be noted that, from the fixed layer 21 to the second magnetic film 233, the magnetic tunneling junction element 2 of the present invention has the same material and characteristics as the embodiment illustrated in FIG. 2, for example, for example. The thickness of the non-magnetic film 232 needs to be greater than or equal to 24 angstroms, and the magnetization directions of the first magnetic film 231 and the second magnetic film 233 exhibit antiferromagnetic coupling. In addition, in an embodiment, a first non-magnetic transition may be respectively disposed between the first magnetic film 231 8 Π 135] 201106351 . and the tunneling layer 22 and between the second magnetic film 233 and the second electrode layer 24 The metal layer and the second non-magnetic transition metal layer (not shown) are preferred, and pt or Pd is preferred as the perpendicular anisotropy of the non-magnetic transition metal layer. Therefore, by the magnetic tunneling junction element of the present invention, the free layer exhibits vertical heterogeneity and antiferromagneticity, so that the magnetic moment of the magnetic memory reverses the current density, thereby increasing the stability of the magnetic domain and the rate of change of the magnetoresistance. improve. Furthermore, please refer to FIG. 4A and FIG. 4D. FIG. 4A to FIG. 4C are diagrams showing the relationship between the applied magnetic field and the magnetic moment reversal formed on the free layer of the present invention formed on the wearing layer, wherein the rectangular dotted line The magnetic field of the applied magnetic field from +400 to -400 and back to +4〇〇〇e is displayed, while the circular point line shows the local hysteresis curve, while in Figure 4A, The magnetic moment value decreases when the magnetic field is about +50 Oe and is flat when the magnetic field is +50 to -150 Oe. On the other hand, the layer structure of this embodiment is prepared as follows. First, a tunneling layer MgO having a thickness of 5 angstroms is deposited on a φ substrate such as a dioxide thin film by a conventional semiconductor thin film deposition method, and a free layer is deposited, that is, a Co layer having a thickness of 4 angstroms is deposited in sequence, and the thickness is X angstrom. A Pt layer and a Co layer having a thickness of 4 angstroms. However, in the example shown in FIG. 4A, after forming the tunneling layer and the free layer, two Pt layers are formed as the first non-magnetic transition metal layer and the second non-magnetic transition metal layer, respectively. Fig. 4A is a stacked structure of a non-magnetic thin film SiO2/MgO(15)/Pt(20)/Co(4)/Pt(24)/Co(4)/Pt(6) having a thickness of 24 Å. Similarly, the structures shown in FIGS. 4B and 4C have SiO2/MgO(15)/Pt(20)/Co(4)/Pt(28)/Co(4)/Pt(6) and 9 respectively. 111351 201106351
Si02/Mg0(15)/Pt(20)/C〇(4)/Pt(32)/C〇(4)/Pt(6)之堆疊結 構。於實施例中，實驗數據顯示當Pt的厚度χ為2〇時， 尚未呈現反鐵磁搞合狀態，而如第4Α至4C圖所示，於大 於或等於24埃時，兩Co層呈現反鐵磁耦合狀態。 於另一實施例中，本發明提供磁性記憶體之製作。首 先於二氧化矽基板上沉積厚度200埃的Ta作為第一電 極’接著於基板上成長包括鐵磁性材料與白金族材料多層 結構之固定層[Pt(18)/Co(6)]3，具體而言，該固定層之堆疊 結構為 Pt(l 8)/Co(6)/Pt(l 8)/Co(6)/Pt(l 8)/Co(6)，接著於固 參 疋層上成長厚度15 i矢MgO作為穿随層，再成長自由層， 即具有兩層厚度4埃之Co層，且其中夾設厚度28埃之Pt 層 Co(4)/Pt(28)/Co(4) 以 形 成The stacked structure of Si02/Mg0(15)/Pt(20)/C〇(4)/Pt(32)/C〇(4)/Pt(6). In the embodiment, the experimental data shows that when the thickness P of the Pt is 2〇, the antiferromagnetic engagement state has not yet been exhibited, and as shown in the fourth to fourth CC diagrams, when the thickness is greater than or equal to 24 angstroms, the two Co layers are reversed. Ferromagnetic coupling state. In another embodiment, the invention provides for the fabrication of magnetic memory. First, a thickness of 200 angstroms of Ta is deposited as a first electrode on the ceria substrate, and then a fixed layer [Pt(18)/Co(6)]3 comprising a ferromagnetic material and a multi-layer structure of a platinum-based material is grown on the substrate, specifically In terms of the fixed layer, the stack structure is Pt(l 8)/Co(6)/Pt(l 8)/Co(6)/Pt(l 8)/Co(6), and then on the solid layer. The growth thickness of 15 i-vector MgO is used as a wear-through layer, and then a free layer is grown, that is, a Co layer having two layers of 4 angstroms in thickness, and a Pt layer of Co(4)/Pt(28)/Co (4) having a thickness of 28 angstroms is interposed therebetween. To form
SiO2/Ta/(200)/[Pt(18)Co(6)]3/MgO(15)/Pt(20)/Co(4)/Pt(28)/ Co(4)/Pt(6)/Ta/(200)之堆疊結構。如第4D圖所示，矩形點 折線顯示外加磁場由正+600到-600再回到+600 Oe之磁滯 曲線（major loop)，而圓形點折線顯示第一局部磁滯曲線 籲 (minor loop )’三角形點折線顯示第二局部磁滞曲線。當自 由層呈現為垂直異向性且第一磁性薄膜（Co)及第二磁性薄 膜（Co)為反鐵磁性耦合而應用於磁性記憶體，自由層中的 磁化方向呈現反平行搞合態。由於反平行搞合態的飽和磁 化量較小，且磁性薄膜飽和磁化量與翻轉電流為正相關’ 故可降低磁矩翻轉電流密度，令本發明磁性記憶體具有提 升磁區穩定性及磁阻變化率之優點。 綜上所述，本發明之磁性穿隧接面元件以及磁性記憶 11135] 201106351 單元，其自由層係包括鐵磁性材料（如Co及Fe)及白金族 材料（如Pt及Pd)之多層堆疊結構，以形成兩鐵磁性層間之 反鐵磁結構，且兩鐵磁性層（Co)之間所夾設之非磁性薄膜 (Pt)的厚度需大於等於24埃，使得自由層呈現反平行耦 合。藉由本發明之實施，可製成微小化的磁性隨機存取記 憶體（MRAM)，除可解決習知技術中如容易去磁等既有缺 失外，更可降低自由層之磁矩翻轉電流密度，並達到增加 磁區穩定性及提高磁阻變化率之功效。 ® 上述各實施例僅例示性說明本發明之原理及功效，而 非用於限制本發明。任何熟習此項技術之人士均可在不違 背本發明之精神及範疇下，對上述實施例進行修飾與改 變。因此，本發明之權利保護範圍，應如後述之申請專利 範圍所列。 【圖式簡單說明】 第1圖係顯示習知技術之磁性穿隧接面元件之結構示 鲁意圖； 第2圖係顯示本發明之磁性穿隧接面元件之結構示意 圖； 第3圖係顯示本發明之磁性記憶體之結構示意圖； 第4A至4C圖係顯示形成於穿隧層上之本發明自由 層中之外加磁場與磁矩翻轉之關係圖；以及 第4D圖係顯示本發明之磁性記憶體之外加磁場與磁 矩翻轉之關係圖。 【主要元件符號說明】 ]]]35] 201106351 1、2 磁性穿隧接面元件 3 磁性記憶體 11 ' 21 固定層 12、 22 穿隧層 13、 23 自由層 231 第一磁性薄膜 232 非磁性薄膜 233 第二磁性薄膜 24 第·一電極層 24, 第二電極層 12 ]]]35]SiO2/Ta/(200)/[Pt(18)Co(6)]3/MgO(15)/Pt(20)/Co(4)/Pt(28)/ Co(4)/Pt(6)/ Stack structure of Ta/(200). As shown in Fig. 4D, the rectangular dot line shows the applied magnetic field from plus +600 to -600 and back to the +600 Oe hysteresis curve, while the circular point line shows the first partial hysteresis curve (minor Loop ) 'The triangle point line shows the second partial hysteresis curve. When the free layer exhibits a vertical anisotropy and the first magnetic film (Co) and the second magnetic film (Co) are applied to the magnetic memory by antiferromagnetic coupling, the magnetization direction in the free layer exhibits an anti-parallel state. Since the amount of saturation magnetization of the anti-parallel state is small, and the saturation magnetization of the magnetic film is positively correlated with the inversion current, the magnetic moment inversion current density can be reduced, so that the magnetic memory of the present invention has improved magnetic domain stability and magnetoresistance. The advantage of the rate of change. In summary, the magnetic tunneling junction element of the present invention and the magnetic memory 11135] 201106351 unit, the free layer includes a multilayer stack structure of ferromagnetic materials (such as Co and Fe) and platinum family materials (such as Pt and Pd). To form an antiferromagnetic structure between the two ferromagnetic layers, and the thickness of the non-magnetic film (Pt) interposed between the two ferromagnetic layers (Co) needs to be greater than or equal to 24 angstroms, so that the free layer exhibits anti-parallel coupling. Through the implementation of the present invention, a miniaturized magnetic random access memory (MRAM) can be fabricated, which can reduce the magnetic moment inversion current density of the free layer, in addition to the prior art, such as easy demagnetization and the like. And achieve the effect of increasing the stability of the magnetic domain and increasing the rate of change of magnetoresistance. The above embodiments are merely illustrative of the principles and effects of the invention and are not intended to limit the invention. Modifications and variations of the above-described embodiments can be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention should be as set forth in the scope of the patent application to be described later. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing the structure of a magnetic tunneling junction member of the prior art; FIG. 2 is a schematic view showing the structure of a magnetic tunneling junction member of the present invention; A schematic view of the structure of the magnetic memory of the present invention; FIGS. 4A to 4C are diagrams showing the relationship between the applied magnetic field and the magnetic moment inversion in the free layer of the present invention formed on the tunneling layer; and the 4D drawing shows the magnetic property of the present invention. The relationship between the magnetic field and the magnetic moment flipping outside the memory. [Major component symbol description] ]]]35] 201106351 1,2 Magnetic tunneling junction element 3 Magnetic memory 11 ' 21 Fixed layer 12, 22 Tunneling layer 13, 23 Free layer 231 First magnetic film 232 Non-magnetic film 233 second magnetic film 24 first electrode layer 24, second electrode layer 12]]] 35]