TWI326886B - Electro-magnetic noise absorbing film - Google Patents
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- TWI326886B TWI326886B TW93106031A TW93106031A TWI326886B TW I326886 B TWI326886 B TW I326886B TW 93106031 A TW93106031 A TW 93106031A TW 93106031 A TW93106031 A TW 93106031A TW I326886 B TWI326886 B TW I326886B
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- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 10
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Description
1326886 玖、發明說明: (一) 發明所屬之技術領域 本發明係關於在高頻率範圍具有高透磁率之磁性材料 ,詳細來說,係關於用以抑制變成雜訊之高頻電流的電磁雜 訊吸收薄膜。 (二) 先前技術 磁性材料所具有之高透磁率係不能以半導體來實現,其 感應係可於數Hz〜數百MHz大範圍之頻率範圍中來利用。 然而,在該等以上之高頻率中,高電阻之實現或磁共振現象 之控制變得困難,不能得到如在低頻所顯示之特性。然而, 隨著磁記錄之高密度化、感應元件之高頻化而強化在GHz 帶動作之磁性材料的要求。 習知於高頻使用之代表磁性材料方面,有肥粒鐵、金屬 薄膜、或複合金屬與非磁性絕緣體之多層膜、或者粒狀薄膜 等。 肥粒鐵係電阻非常高而幾乎爲絕緣體,由於在高頻中之 渦電流產生非常少而以塊狀形狀來使用。然而,在數10 MHz 以上之高頻時則引起磁壁之共振振動與旋轉共振現象,而出 現所謂蛇形界線。再者,爲了提高頻率,形成數μχη以下之 薄膜形狀來增加磁形狀各向異性而拉升斯洛克界限(Snoek limit)雖然有效果,但是具有高透磁率之肥粒鐵相的形成中 ,由於必須有l〇〇〇°C左右之處理,故薄膜之形成變得困難, 非實用之範例。 又,金屬薄膜係使用高導磁合金(Ni8QFe2Q)、非晶型 1326886 金屬爲代表,雖然得到非常高之透磁率,但因高導電率而容 易產生渦電流,隨著變成高頻而限制膜厚。特別在GHz以上 ,非0.1 μιη以下時則引起渦電流之問題。 因此,積層上述之多層膜、即金屬薄膜與氧化物等之絕 緣體薄膜並使用抑制渦電流之薄膜材料,由於減少全體磁化 之大小,且生產程序變得複雜等,該利用係有所限制。 粒子薄膜係具有最近開發之粒子構造之薄膜,強磁性金 屬微粒子分散於氧化物等母體中,實現了比金屬高數個位數 之電阻。粒子構造係在以原子程度混合金屬與氧化物時本身 組織地來形成,以於氧化物中析出l〇nm以下直徑之磁性金 屬微粒子之構造、具體來說係藉由濺鍍法等之薄膜製造技術 來製作。粒子膜係由於可具有高電阻同時具有因微粒子之異 方鍵結造成之強磁各向異性,因此可抑制或控制GHz帶中之 旋轉共振現象之產生。粒子薄膜雖被認爲比習知薄膜材料之 應用範圍較廣,但具有如以下之問題。 首先,製作粒子構造之強磁性金屬微粒子,其本身爲數 nm直徑,在獨立狀態下係因室溫之熱擾亂而導致失去強磁 性(超常磁性現象)。爲了使其具有強磁性,則使微粒子間 具有磁性鍵結來克服熱擾亂。此時,因磁性鍵結所形成之微 粒子展現成爲集結之磁性質,而變爲顯示高透磁率。即,爲 了得到作爲高透磁率薄膜之性質,則不可欠缺微粒子間之磁 鍵結。該磁鍵結中,必須於絕緣體中之微粒子間有金屬鍵結 來降低電阻。因此,在成爲高透磁率與電阻爲反比之參數的 粒子構造中係對於電阻有上限。 -7- 1326886 其次,於GHz帶中之高透磁率材料應用技術方面,有 磁記錄中之讀寫頭用材料、及控制旋轉磁共振吸收之頻帶之 電磁雜訊吸收材料。粒子薄膜係有希望成爲因高電阻所產生 之雜訊吸收材料。然而,爲了使於GHz帶之共振吸收有效操 作’已知更需要數位數高之電阻。 其中,本發明之目的係提供抑制超常磁性同時提高電阻 ,又具備可控制旋轉共振現象之微粒子構造膜的電磁雜訊吸 收薄膜。 (三) 發明內容 本發明者等,爲了解決前述之目的,設定電磁雜訊吸收 材料之設計方針,發現可使其具體實現化之嶄新技術,而達 到完成本發明。 即,根據本發明,可得到一電磁雜訊吸收薄膜,其特徵 爲具有一構造,係把由Fe' Co'或Ni等各種金屬或者至少 含有20重量%之該等金屬的合金所構成之柱狀構造體埋設 於氧化物、氮化物或氟化物或者該等的混合物之無機質絕緣 性母體中。 (四) 實施方式 用於實施發明之最佳熊樣 首先,說明本發明之原理。 於粒子構造中,由於本身組織地形成微粒子,其形狀約 略接近於球狀。此時,引起超常磁性之條件係由以下通式( 1 )所示。1326886 发明Invention Description: (I) Field of the Invention The present invention relates to a magnetic material having a high magnetic permeability in a high frequency range, and more particularly to electromagnetic noise for suppressing a high frequency current which becomes noise. Absorbing film. (II) Prior Art The high magnetic permeability of the magnetic material cannot be realized by a semiconductor, and the sensing system can be utilized in a frequency range of a large range of several Hz to several hundreds of MHz. However, at these higher frequencies, the realization of high resistance or the control of the magnetic resonance phenomenon becomes difficult, and characteristics as shown at low frequencies cannot be obtained. However, with the increase in density of magnetic recording and the high frequency of the sensing element, the demand for magnetic materials operating in the GHz band is enhanced. The magnetic material which is conventionally used for high frequency use includes a ferrite iron, a metal film, a multilayer film of a composite metal and a non-magnetic insulator, or a granular film. The ferrite-based iron-based resistor is very high and is almost an insulator, and is used in a block shape because the eddy current is generated at a high frequency and is very small. However, at a high frequency of several 10 MHz or more, resonance vibration and rotational resonance of the magnetic wall are caused, and a so-called serpentine boundary line appears. Further, in order to increase the frequency, the film shape of several μχη or less is formed to increase the magnetic shape anisotropy, and the Snoek limit is effective, but in the formation of the ferrite grain iron phase having high magnetic permeability, There must be a treatment of about 10 °C, so the formation of the film becomes difficult, a non-practical example. Further, the metal thin film is represented by a high magnetic permeability alloy (Ni8QFe2Q) or an amorphous type 1326886 metal, and although a very high magnetic permeability is obtained, an eddy current is easily generated due to high conductivity, and the film thickness is restricted as it becomes a high frequency. . Especially in the case of GHz or more, when it is not more than 0.1 μm, the problem of eddy current is caused. Therefore, the use of the above-mentioned multilayer film, that is, the insulating film such as a metal thin film and an oxide, and the use of a film material for suppressing eddy currents, is limited by the reduction of the total magnetization and the complicated production process. The particle film is a film having a recently developed particle structure in which ferromagnetic metal fine particles are dispersed in a matrix such as an oxide to realize a resistance higher than a single digit of a metal. The particle structure is formed by laminating a metal and an oxide atomically, and a structure in which magnetic metal fine particles having a diameter of 10 nm or less are deposited in the oxide, specifically, a film by sputtering or the like. Technology to make. The particle film system can suppress or control the generation of the rotational resonance phenomenon in the GHz band because it can have high electric resistance and strong magnetic anisotropy due to the heterojunction of the fine particles. Although the particle film is considered to have a wider application range than the conventional film material, it has the following problems. First, the ferromagnetic metal microparticles of the particle structure are produced in a diameter of several nm, and in a state of independence, the strong magnetic properties (supernormal magnetic phenomenon) are lost due to heat disturbance at room temperature. In order to make it ferromagnetic, magnetic bonds are made between the microparticles to overcome thermal disturbances. At this time, the microparticles formed by the magnetic bonding exhibit a magnetic property of aggregation, and become high magnetic permeability. Namely, in order to obtain the properties as a high magnetic permeability film, the magnetic bond between the fine particles is indispensable. In this magnetic bond, there must be a metal bond between the particles in the insulator to reduce the resistance. Therefore, in the particle structure which is a parameter whose inverse magnetic permeability is inversely proportional to the electric resistance, there is an upper limit to the electric resistance. -7- 1326886 Secondly, in the application technology of high magnetic permeability materials in the GHz band, there are materials for reading and writing heads in magnetic recording, and electromagnetic noise absorbing materials for controlling the frequency band of rotational magnetic resonance absorption. The particle film is expected to be a noise absorbing material due to high resistance. However, in order to make the resonance absorption of the GHz band effective, it is known that a resistance of several digits is required. Among them, an object of the present invention is to provide an electromagnetic noise absorbing film which suppresses super-magnetic properties while improving electrical resistance and has a fine particle structure film which can control a rotational resonance phenomenon. (3) DISCLOSURE OF THE INVENTION In order to solve the above-mentioned problems, the inventors of the present invention have set a design policy of an electromagnetic noise absorbing material and found a new technology that can be specifically realized, and have completed the present invention. That is, according to the present invention, an electromagnetic noise absorbing film having a structure in which a column composed of various metals such as Fe' Co' or Ni or an alloy containing at least 20% by weight of such metals is obtained is obtained. The structural body is embedded in an inorganic insulating matrix of an oxide, a nitride or a fluoride or a mixture thereof. (4) Embodiments The best bear sample for carrying out the invention First, the principle of the present invention will be explained. In the particle structure, since the microparticles are formed by themselves, the shape is approximately spherical. At this time, the condition causing the extraordinary magnetic property is represented by the following general formula (1).
KuV/kT< 1 1326886 其中,於上述通式(1)中,k爲波茨曼常數、T爲溫度 (凯文、K)、Ku爲金屬微粒子原本具有之磁各向異性大小 。KuV爲具有一個微粒之磁能,其係與熱擾亂能量kT相同 程度並顯現超常磁性。高電阻粒子薄膜之Fe或Co微粒子大 小約爲5nm,以上述條件則完全在超常磁性範圍或超常磁性 之交界內。 然而,以粒子構造則由於微粒子間具有磁鍵結,抑制著 超常磁性。爲了提高電阻,則增加氧化物含有率,並切斷該 磁鍵結而形成超常磁性。 其中,於本發明中,以人工控制微粒子形狀而賦予形狀 磁各向異性來作爲使該Ku變大之方法。即,未出現超常磁 性之條件係由以下通式(2 )來變化。KuV/kT<1 1326886 wherein, in the above formula (1), k is a Potsman constant, T is a temperature (Kevin, K), and Ku is a magnetic anisotropy originally possessed by the metal fine particles. KuV is a magnetic energy having a particle which is at the same level as the thermal disturbance energy kT and exhibits extraordinary magnetic properties. The Fe or Co fine particles of the high-resistance particle film have a size of about 5 nm, and are completely in the boundary between the super-magnetic range and the super-magnetic state under the above conditions. However, in the particle structure, since the magnetic bonds are present between the microparticles, the super-magnetic property is suppressed. In order to increase the electric resistance, the oxide content is increased, and the magnetic bond is cut to form an extraordinary magnetic property. In the present invention, the shape magnetic anisotropy is artificially controlled to impart shape magnetic anisotropy as a method for increasing the Ku. Namely, the condition in which the extraordinary magnetic properties do not occur is changed by the following general formula (2).
Kt〇talV/kT> 1 ' Kt〇tal= Ku+ Kus · . . (2) 其中,Kus係微粒子形狀爲非球狀、例如爲棒狀時之形 狀磁各向異性大小,並由以下通式(3)來表示。Kt〇talV/kT> 1 'Kt〇tal= Ku+ Kus · (2) where the shape of the Kus-based fine particles is non-spherical, for example, the shape of the magnetic anisotropy, and is of the following formula ( 3) to express.
Kus = ( 1/2 ) NdMs2 ... ( 3 ) 還有,上述通式(3)中,Nd爲反磁界常數,Ms爲飽 和磁化。 在棒狀爲足夠長的情況下,Nd係由於在長方向爲4π、 在垂直於長方向之直角方向爲〇,故由以下通式(4)表示。Kus = ( 1/2 ) NdMs2 (3) Further, in the above formula (3), Nd is a demagnetization boundary constant, and Ms is a saturation magnetization. In the case where the rod shape is sufficiently long, the Nd system is represented by the following general formula (4) because it is 4π in the longitudinal direction and 〇 in the direction perpendicular to the longitudinal direction.
Kus= 2kMs2 ... ( 4) 因而’由於粒子構造非球狀之集合體,若形成與棒狀一 起存在之構造可使超常磁性臨界體積變小,而可提高微粒子 1326886 例如,Fe具有5xl05erg/Cm3之Ku。在通常之粒子構造 中,假定爲5 nm直徑之球狀微粒子時,則以下通式(5)成 立。Kus= 2kMs2 (4) Therefore, due to the non-spherical aggregate of the particle structure, if the structure existing together with the rod shape is formed, the critical magnetic volume of the extraordinary magnetic material can be made smaller, and the fine particle 1326886 can be increased. For example, Fe has 5xl05erg/ Ku of Cm3. In the usual particle structure, when spherical microparticles having a diameter of 5 nm are assumed, the following general formula (5) is established.
KuV/kT =0.9 . · · ( 5 ) 以相同體積認爲Nd= 4π之3nm直徑的圓柱狀微粒子則 變成以下通式(6 )。KuV/kT = 0.9. (5) The cylindrical fine particles having a diameter of 3 nm of Nd = 4π in the same volume become the following general formula (6).
Kus = ( 1/2 ) NdMs2 . · · ( 6 ) 由該通式(6 ),得到以下通式。Kus = ( 1/2 ) NdMs2 . (6) From the general formula (6), the following general formula is obtained.
Kt〇tai = Kus + Ku = 3><107 erg/cm3 因此,可導出以下通式(7)。Kt〇tai = Kus + Ku = 3><107 erg/cm3 Therefore, the following general formula (7) can be derived.
Kt〇taiV/kT= 200 ... ( 7 ) 由以上得知,藉由控制微粒子形狀,即使獨立於絕緣體 中之微粒子亦可抑制超常磁性,電阻則飛快地上升。 其次,描述有關於透磁率、磁共振頻率之控制。 透磁率μ與磁共振頻率fr係以微粒子所具有之磁各向 異性Kt()tal來決定。即由以下之通式(8)及通式(9)來表 示。 μ = 2nMs2/K,otai · . · ( 8 ) fr = γχ ( 2Ktotai/Ms ) ... ( 9 ) 但是,於上述通式(9)中,γ爲家宜洛磁係數。 因此,亦可藉由微粒子形狀控制透磁率、磁共振頻率。 本發明者等,進行可具體實現上述之設計方針的新技術 ,而達到完成本發明。 本發明係使用於以下所說明之複合材料。該複合材料係 1326886 具有將由Fe、Co、或Ni各種純金屬或者至少含有20重量 %該等金屬之合金所構成的柱狀構造體埋設於其爲氧化物 、氮化物或氟化物或者’該等物質之混合物的無機質絕緣性母 體中的構造。使用該複合材料來製作薄膜。其中將所得之薄 膜稱爲電磁雜訊吸收薄膜。 該電磁雜訊吸收薄膜係前述柱狀構造具有單磁區構造 ,而且前述柱狀構造體直徑D爲InmSDS lOOOnm。然後, 前述柱狀構造體直徑D與長L之比例(長徑比L/D)爲 1 $ L/D ^ 1 000。 又,電磁雜訊吸收薄膜係前述柱狀構造體於長方向具有 磁化容易軸,同時具有經由前述無機質絕緣性母體約略平行 於直徑方向地重複排列多數個柱狀構造體的構造,相對於前 述多數個柱狀構造體之長方向,相鄰之柱狀構造體的間隙( 存在於間隙之前述絕緣性母體厚度)在0〜10 OOnm之範圍, 更希望在0.1nm~1 000nm (更希望爲l~10nm )之範圍。 又,電磁雜訊吸收薄膜係前述柱狀構造體於長方向具有 磁化容易軸,同時具有經由前述無機質絕緣性母體於長方向 重疊所重複配置排列多數個前述柱狀構造體的構造。然後, 相對於前述多數個柱狀構造體的直徑方向,相鄰之柱狀構造 體的間隙(或存在於間隙之前述絕緣性母體的厚度)在 0.1nm~100nm 之範圍》 又,電磁雜訊吸收薄膜係由經由厚度在lnm~100nm範 圍之絕緣性母體而重疊之多數個柱狀構造體層所構成,其爲 前述各個柱狀構造體層由長徑比L/D互相不同之柱狀構造 1326886 體所構成之磁性層。 再者,其爲電磁雜訊吸收薄膜之飽和磁致伸縮常數絕對 値I |爲丨丨S60ppm、以電磁雜訊吸收薄膜之直流的電 阻率在102~109μΩ · cm之範圍的電磁雜訊吸收薄膜。 又,前述電磁雜訊吸收薄膜爲厚度t之薄膜狀磁性體, 且前述柱狀構造體之長方向與前述薄膜狀磁性體之厚方向 略爲平行或前述柱狀構造體之長方向相對於前述薄膜狀磁 性體之厚方向成爲平均角度Θ傾斜而形成,前述Θ在 0$θ$9 0°之範圍。還有,由於可使於膜的厚度方向具有磁化 容易軸,並可提高於面方向之電阻,特別具有效果,前述Θ 係以〇$θ$20°之範圍爲佳》 又,本發明之電磁雜訊吸收薄膜係經由厚度t之絕緣性 母體多數個重疊而形成由長徑比L/D互相不同之柱狀構造 體所構成之磁性層,該電磁雜訊吸收薄膜係具有相當於前述 柱狀構造體層數之數目、或、其以下之多數個磁共振。 其次,更詳細地說明本發明。 在製作具有粒子構造之薄膜中,由於有同時混入氧化物 與強磁性金屬之必要,濺鍍法爲方便且迄今仍被使用著。於 濺鍍法中係由於入射於基板之粒子運動能量非常高,氧化物 與強磁性金屬能有效率地混合而成爲約略非晶型狀態。因此 ,約略之粒子材料係通過藉由熱處理之相分離過程而得到前 述粒子構造。 於本發明中,係藉由二次元蒸鍍法製作氧化物與金屬。 蒸鍍法中比較於濺鍍法,熟知由於到達基板上之原料原子或 1326886 分子之運動量特別小,而在累積重疊於基板上之過程中製作 柱狀的細微構造。於本發明中係利用製作該柱狀構造之原理 。再者,藉由以適當之蒸鍍速度、即體積比例同時於基板上 形成氧化物與金屬,來形成有效分離之柱狀(棒狀)微粒子 。其中稱具有強磁性柱狀體之粒子構造爲柱狀粒子構造。 在濺鍍法中,相對於用來通過其熱處理等之粒子形成處 理步驟之粒子型狀爲近乎球狀之不定形狀,於蒸鍍法中,即 使無熱處理亦爲相分離,而強磁性金屬形成長的柱狀構造。 因此,成爲如前述由於形狀之磁各向異性而獨立之強磁性體 亦變成高透磁率。於控制該透磁率中,亦可縮短強磁性柱狀 體之長度來變化形狀磁各向異性。強磁性柱狀體之長度係由 於與強磁性體之蒸發源快門開啓時間成正比,可藉由週期地 開關該快門來控制縮短強磁性柱狀體之長度。強磁性柱狀體 變短時,則上述通式(6 )之Nd降低至4π以下,藉由降低 磁各向異性來增加透磁率。同時亦可由上述通式(9)之關 係來變化磁共振頻率。 又,於蒸鍍中藉由改變快門開啓時間,可於一種材料中 重疊具有不同之多數個共振頻率之微粒子層。藉由該控制方 法,一點一點並聯不同敏銳的磁共振吸收,由於可正確地控 制所希望之頻率範圍的磁損失,其爲用於提高作爲電磁波吸 收體性能的有效方法。 還有,於習知之粒子構造中,由於因粒子間之鍵結而產 生磁各向異性,該方向係平行於膜面。因而透磁率之大小係 隨磁各向異性之方向而敏感地變化。即,對於透磁率之大小 [S ] -13- 1326886 有強的面內指向性。 相對於此,於本發明之柱狀粒子構造中,於膜厚方向具 有磁各向異性,於膜面內則無指向性。即,柱狀粒子構造係 具有顯示等方透磁率之特徵,在要求等方干擾吸收性能之情 況下爲有效的。然而,由於其爲等方所導致之該透磁率大小 則變成其爲面內指向性之情況的一半》於本發明中可針對該 材料之用途來配置面內指向性。於蒸鍍法中,可藉由改變相 對於蒸發源之基板角度來控制入射於基板之粒子角度。即, 可自由地由膜厚方向來傾斜強磁性柱狀體的長方向。 於本發明中利用該方法時,則隨著強磁性柱狀體傾斜而 產生從膜厚方向傾斜於面內方向之磁各向異性。因此,由等 方透磁性變化成爲具有指向性之透磁率。 於如以上之本發明中,具有所謂在由膜厚方向至面內之 所希望的方向賦予強磁各向異性,再者可設計、控制透磁率 方向'大小、共振頻率、再者其頻帶,同時由於不必熱處理 而可自由選擇基板,再者可高速製作之特長。 此處,說明本發明之實例。 於第1圖之電子顯微鏡照片中,(a)爲藉由濺鍍法所 得之粒子構造( 300°C、熱處理1小時後)、(b)爲於膜截 面觀察藉由蒸鍍所得之柱狀構造者。 如第1圖(a)及(b)所示,於濺鍍法中係藉由該粒子 形成步驟而使粒子形狀成爲約略近乎球狀之不定形狀,於蒸 鍍法中係即使無熱處理亦爲相分離,強磁性金屬係形成長柱 狀構造。相對於第1圖(a)之電阻爲1000 μΩ· cm,第1圖 1326886 (b)爲 1 ΟΟΟΟΟμΩ · cm。 參照第2圖,則見透磁率之頻率特性,且於第2圖(a )之蒸鍍膜中,透磁率雖低,但於特定之頻率中得到敏銳之 磁共振損失。該理由爲由於因聚集較佳之柱狀結構而產生磁 各向異性,約略無分散,因而出現明確之磁共振。 另外,於第2圖(b)之濺鍍膜中則在寬頻率範圍中發 現共振損失’不能得到於所希望之頻率範圍中的磁共振。該 理由爲在第2圖(b)中係由於以粒子間鍵結狀態決定磁共 振之磁各向異性,而大爲分散之緣故。 第3圖係爲了控制透磁率而改變快門時間來提高透磁 率之實例’顯示快門開啓時間與透磁率、共振頻率之關係圖 。如第3圖所示,以習知之粒子薄膜,可進行其爲困難之透 磁率的精密控制。又,於蒸鍍中藉由改變快門開啓時間,可 於一種材料中重疊具有不同之多數個共振頻率的微粒子層。 參照第4圖時,則由從1 〇秒至200秒階段地改變快門 時間來製作一個試樣之情況的透磁率,判斷於整個約略設計 之頻帶中引起磁共振。 參照第5圖(a) 、(b)及(c)來說明傾斜基板來控 制透磁率之面內指向性的範例時,首先,如第5圖(a)所 示,在基板對抗於蒸發源之情況(ψ=〇)下,在等方、傾斜 之情況(Ψ=45°)下則出現指向性,在μ之測定方向爲第5 圖(b)及(c)中之y方向(0=〇°),透磁率變大》 其次,硏究以本發明所得之電磁雜訊吸收薄膜之電磁雜 訊吸收效果。 [S ] -15- 1326886 如第6圖所示,由形成於絕緣基板62b上之微帶導體 62a所構成之微帶線路62上配置於本發明中所得之電磁雜 訊吸收薄膜試樣61,連接微帶線路62之兩端於網路分析儀 63,觀察傳導特性S11及S21。 參照第7圖及第8圖,說明設置基於本發明實例所製作 之多數個電磁雜訊吸收薄膜試樣於微帶線路上時之傳導特 性 S11 及 S21 » 如由第7圖所得知,顯示反射之傳導特性S11的大小, 在本發明實例與比較例中差別不大,而在使用任何試樣之情 況下,均判斷爲實用程度之反射量。另外顯示透過損失之傳 導特性S21如由第8圖所得知,本發明試樣比較於比較試樣 爲大,所謂電磁雜訊吸收效果高。 第9圖(a)係顯示形成本發明電磁雜訊吸收薄膜於接 地線之主動元件封裝電路基板之一範例的上視圖,以電路圖 槪略地顯示。又,第9圖(b)係第9圖(a)之電磁雜訊吸 收薄膜之側面圖。第10圖係顯示第9圖(a)及第9圖(b )之電磁雜訊吸收薄膜的放射雜訊減低效果圖。 如第9圖(a)及第9圖(b)所示,基於本發明所製作 之電磁雜訊吸收薄膜71成膜於封裝IC7 1作爲主動元件之電 路基板73上的一部分接地線72上,來比較驅動該電路時所 產生之放射電磁雜訊。還有,C爲電容器等被動電路元件74 〇 該結果如第10圖所示,在電路基板上之一部份上使以 實線曲線77所示之電磁雜訊吸收薄膜成膜,使此電路動作Kt〇taiV/kT=200 (7) From the above, by controlling the shape of the fine particles, even if the particles are independent of the insulator, the super-magnetic property can be suppressed, and the electric resistance rises rapidly. Secondly, the control of the magnetic permeability and the magnetic resonance frequency is described. The magnetic permeability μ and the magnetic resonance frequency fr are determined by the magnetic anisotropy Kt()tal of the fine particles. That is, it is represented by the following general formula (8) and general formula (9). μ = 2nMs2/K, otai · · · ( 8 ) fr = γχ ( 2Ktotai/Ms ) (9) However, in the above formula (9), γ is the home magnetic coefficient. Therefore, the magnetic permeability and the magnetic resonance frequency can also be controlled by the shape of the fine particles. The inventors of the present invention have completed the present invention by implementing a new technique that can specifically implement the above-described design guidelines. The invention is used in the composite materials described below. The composite material system 1326886 has a columnar structure composed of various pure metals of Fe, Co, or Ni or an alloy containing at least 20% by weight of such metals, which are embedded in oxides, nitrides, or fluorides or A structure in an inorganic insulating matrix of a mixture of substances. The composite material is used to make a film. The resulting film is referred to as an electromagnetic noise absorbing film. In the electromagnetic noise absorbing film, the columnar structure has a single magnetic domain structure, and the columnar structure has a diameter D of InmSDS 100Onm. Then, the ratio of the diameter D of the columnar structure to the length L (length to diameter ratio L/D) is 1 $ L/D ^ 1 000. Further, the electromagnetic noise absorbing film has a structure in which the columnar structure has a magnetization easy axis in the longitudinal direction and a plurality of columnar structures are repeatedly arranged substantially parallel to the diameter direction via the inorganic insulating matrix, and the plurality of columnar structures are arranged. The longitudinal direction of the columnar structures, the gap between the adjacent columnar structures (the thickness of the insulating matrix present in the gap) is in the range of 0 to 100 nm, and more desirably in the range of 0.1 nm to 1 000 nm (more desirably ~10nm) range. In the electromagnetic noise absorbing film, the columnar structure has a structure in which a plurality of the columnar structures are arranged in a long direction by overlapping the magnetizable precursors in the longitudinal direction. Then, the gap between the adjacent columnar structures (or the thickness of the insulating matrix existing in the gap) is in the range of 0.1 nm to 100 nm with respect to the diameter direction of the plurality of columnar structures, and electromagnetic noise The absorbing film is composed of a plurality of columnar structure layers which are superposed by an insulating matrix having a thickness in the range of 1 nm to 100 nm, and each of the columnar structure layers has a columnar structure 1326886 in which the aspect ratio L/D is different from each other. The magnetic layer formed. Furthermore, it is an electromagnetic noise absorbing film in which the saturation magnetostriction constant of the electromagnetic noise absorbing film is 値I | is 60S60 ppm, and the DC resistivity of the electromagnetic noise absorbing film is in the range of 102 to 109 μΩ · cm. . Further, the electromagnetic noise absorbing film is a film-shaped magnetic body having a thickness t, and a longitudinal direction of the columnar structure is slightly parallel to a thickness direction of the film-shaped magnetic body or a longitudinal direction of the columnar structure is opposite to the foregoing The thickness direction of the film-like magnetic body is formed so that the average angle Θ is inclined, and the enthalpy is in the range of 0$θ$9 0°. Further, since it is possible to have a magnetization easy axis in the thickness direction of the film and to increase the electric resistance in the surface direction, it is particularly effective, and the above-mentioned enthalpy is preferably in the range of 〇$θ$20°. The absorbing film is formed by a plurality of insulating mother bodies having a thickness t, and a magnetic layer composed of columnar structures having different aspect ratios L/D is formed. The electromagnetic noise absorbing film has a columnar structure corresponding to the columnar structure. The number of layers, or a plurality of magnetic resonances below it. Next, the present invention will be described in more detail. In the production of a film having a particle structure, the sputtering method is convenient and has been used until now due to the necessity of mixing oxide and ferromagnetic metal at the same time. In the sputtering method, since the kinetic energy of the particles incident on the substrate is very high, the oxide and the ferromagnetic metal can be efficiently mixed to become an approximately amorphous state. Therefore, the approximate particle material is obtained by the phase separation process by heat treatment to obtain the above-described particle structure. In the present invention, an oxide and a metal are produced by a secondary vapor deposition method. In the vapor deposition method, it is known that the columnar fine structure is formed in the process of accumulating overlying the substrate because the amount of movement of the raw material atoms or the 1326886 molecules on the substrate is extremely small. In the present invention, the principle of fabricating the columnar structure is utilized. Further, columnar (rod-shaped) fine particles which are effectively separated are formed by simultaneously forming an oxide and a metal on the substrate at an appropriate vapor deposition rate, i.e., a volume ratio. The particles having the ferromagnetic columnar body are referred to as a columnar particle structure. In the sputtering method, the particle shape of the treatment step for forming a particle by heat treatment or the like is a nearly spherical shape, and in the vapor deposition method, phase separation is performed even without heat treatment, and ferromagnetic metal is formed. Long columnar structure. Therefore, the ferromagnetic material which is independent due to the magnetic anisotropy of the shape as described above also becomes high in magnetic permeability. In controlling the magnetic permeability, the length of the ferromagnetic columnar body can also be shortened to change the shape magnetic anisotropy. The length of the ferromagnetic column is proportional to the evaporation source shutter opening time of the ferromagnetic body, and the length of the ferromagnetic column can be shortened by periodically switching the shutter. When the ferromagnetic columnar body becomes shorter, the Nd of the above formula (6) is lowered to 4π or less, and the magnetic permeability is increased by lowering the magnetic anisotropy. At the same time, the magnetic resonance frequency can also be changed by the relationship of the above formula (9). Further, by changing the shutter opening time in vapor deposition, a fine particle layer having a plurality of different resonance frequencies can be overlapped in one material. By this control method, different sharp magnetic resonance absorptions are connected in parallel, and since the magnetic loss in the desired frequency range can be correctly controlled, it is an effective method for improving the performance as an electromagnetic wave absorber. Further, in the conventional particle structure, since the magnetic anisotropy is generated due to the bonding between the particles, the direction is parallel to the film surface. Therefore, the magnitude of the magnetic permeability changes sensitively with the direction of the magnetic anisotropy. That is, there is strong in-plane directivity for the magnitude of the magnetic permeability [S ] -13 - 1326886. On the other hand, in the columnar particle structure of the present invention, magnetic anisotropy is exhibited in the film thickness direction, and no directivity is observed in the film surface. That is, the columnar particle structure has a characteristic of exhibiting an equal magnetic permeability, and is effective in the case where it is required to interfere with the absorption performance. However, since the magnitude of the magnetic permeability is equal to half of the case where it is in-plane directivity, the in-plane directivity can be configured for the use of the material in the present invention. In the vapor deposition method, the angle of the particles incident on the substrate can be controlled by changing the angle of the substrate relative to the evaporation source. That is, the longitudinal direction of the ferromagnetic columnar body can be freely inclined from the film thickness direction. When this method is used in the present invention, magnetic anisotropy which is inclined in the in-plane direction from the film thickness direction occurs as the ferromagnetic columnar body is inclined. Therefore, the magnetic permeability changes from the equal side to the magnetic permeability with directivity. In the above invention, the strong magnetic anisotropy is imparted in a desired direction from the film thickness direction to the in-plane, and the magnetic permeability direction 'size, resonance frequency, and frequency band thereof can be designed and controlled. At the same time, since the substrate can be freely selected without heat treatment, the special length can be produced at a high speed. Here, an example of the invention will be described. In the electron micrograph of Fig. 1, (a) is a particle structure obtained by a sputtering method (300 ° C, heat treatment for 1 hour), and (b) is a columnar shape obtained by vapor deposition on a film cross section. Constructor. As shown in Fig. 1 (a) and (b), in the sputtering method, the particle shape is formed into an approximately spherical shape by the particle forming step, and in the vapor deposition method, even if there is no heat treatment, In phase separation, the ferromagnetic metal forms a long columnar structure. The resistance of Fig. 1(a) is 1000 μΩ·cm, and Fig. 1326886 (b) is 1 ΟΟΟΟΟμΩ · cm. Referring to Fig. 2, the frequency characteristics of the magnetic permeability are shown, and in the vapor deposited film of Fig. 2(a), although the magnetic permeability is low, a sharp magnetic resonance loss is obtained at a specific frequency. This reason is due to the fact that magnetic anisotropy is generated due to aggregation of a preferred columnar structure, and there is almost no dispersion, so that a clear magnetic resonance occurs. Further, in the sputtering film of Fig. 2(b), resonance loss is found in a wide frequency range, and magnetic resonance in a desired frequency range cannot be obtained. The reason for this is that in the second figure (b), the magnetic anisotropy of the magnetic resonance is determined by the state of the interparticle bonding, and the dispersion is largely dispersed. Fig. 3 is a graph showing the relationship between the shutter opening time and the magnetic permeability and the resonance frequency by changing the shutter time in order to control the magnetic permeability to increase the magnetic permeability. As shown in Fig. 3, with the conventional particle film, it is possible to perform precise control of the magnetic permeability which is difficult. Further, by changing the shutter opening time in vapor deposition, a fine particle layer having a plurality of different resonance frequencies can be overlapped in one material. Referring to Fig. 4, the magnetic permeability of a case where a sample is made by changing the shutter time from 1 sec to 200 sec is judged to cause magnetic resonance in the entire approximate design band. Referring to Fig. 5 (a), (b) and (c), an example in which the in-plane directivity of the magnetic permeability is controlled by tilting the substrate will be described. First, as shown in Fig. 5 (a), the substrate is opposed to the evaporation source. In the case (ψ=〇), the directivity occurs in the case of the equal square and the tilt (Ψ=45°), and the direction of the measurement in μ is the y direction in the fifth figure (b) and (c) (0) = 〇 °), the magnetic permeability becomes larger. Next, the electromagnetic noise absorbing effect of the electromagnetic noise absorbing film obtained by the present invention is examined. [S] -15 - 1326886 As shown in Fig. 6, the electromagnetic noise absorbing film sample 61 obtained in the present invention is disposed on the microstrip line 62 formed of the microstrip conductor 62a formed on the insulating substrate 62b, The two ends of the microstrip line 62 are connected to the network analyzer 63 to observe the conduction characteristics S11 and S21. Referring to Figures 7 and 8, a description will be given of the conduction characteristics S11 and S21 when a plurality of electromagnetic noise absorbing film samples produced based on the examples of the present invention are placed on a microstrip line. As shown in Fig. 7, the reflection is shown. The size of the conduction characteristic S11 is not much different between the examples of the present invention and the comparative example, and in the case of using any sample, it is judged to be a practical amount of reflection. Further, the transmission characteristic S21 showing the transmission loss is as shown in Fig. 8. The sample of the present invention is larger than the comparative sample, and the electromagnetic noise absorption effect is high. Fig. 9(a) is a top view showing an example of an active component package circuit substrate which forms the electromagnetic noise absorbing film of the present invention on the grounding wire, and is schematically shown in a circuit diagram. Further, Fig. 9(b) is a side view of the electromagnetic noise absorbing film of Fig. 9(a). Fig. 10 is a view showing the effect of reducing the radiation noise of the electromagnetic noise absorbing film of Figs. 9(a) and 9(b). As shown in FIGS. 9(a) and 9(b), the electromagnetic noise absorbing film 71 produced by the present invention is formed on a part of the ground line 72 on the circuit substrate 73 on which the IC 7 1 is packaged as an active device. To compare the radiated electromagnetic noise generated when the circuit is driven. Further, C is a passive circuit element 74 such as a capacitor. As a result, as shown in Fig. 10, an electromagnetic noise absorbing film shown by a solid line curve 77 is formed on a portion of the circuit substrate to make the circuit. action
-16- 1326886 時所觀測之放射電磁雜訊程度,相較於未設置與以虛線曲線 76所示之比較例有關之電磁雜訊吸收薄膜而言,放射電磁雜 訊程度大爲衰減,由此'推斷可得到有效之電磁雜訊減低效果 〇 於以上說明之本發明之實例中,說明於已搭載主動元件 之電路基板上、例如、於接地線上設置電磁雜訊吸收薄膜之 範例,藉由直接設置於包含同樣電路基板之電子零件、數據 線之一部分、主動元件上或具備主動元件之電子零件的高頻 電流流動部位、例如、金屬框體,當然可得到電子雜訊減低 效果。 如以上說明,根據本發明實施例之電磁雜訊吸收薄膜具 有於高頻中優異之透磁率特性,特別是虛部透磁率特性,使 用該電磁雜訊吸收薄膜之電磁雜訊吸收薄膜具有於高頻中 優異之雜訊吸收效果,對於近年來成爲問題之高頻電磁雜訊 的控制極爲有效。 又,根據本發明,可提供具備抑制超常磁性且提高電阻 ,又可控制旋轉共振現象之微粒子構造膜的電磁雜訊吸收薄 膜。 產業上之利用可行件 由於關於本發明之電磁雜訊吸收薄膜可控制成爲雜訊 之高頻電流,可使用於以個人電腦、行動終端機等爲始之電 子機器或電氣機器。 (五)圖式簡單說明: 第1圖(a)係於膜內面觀察藉由濺鍍法所產生之粒子 [S 3 -17- 1326886 構造(300°C、熱處理1小時後)之電子顯微鏡照片;(b) 係於膜截面觀察藉由蒸鍍所產生之柱狀構造的電子顯微鏡 照片。 第2圖係顯示薄膜透磁率之頻率特性圖;(a) 、(b) 係個別顯示蒸鍍膜、濺鍍膜之透磁率的頻率特性。 第3圖係顯示改變快門時間來控制之透磁率、與共振頻 率之關係圖。 第4圖係從1 0秒至200秒階段地改變快門時間來顯示 製成一個試樣之情況的透磁率測定結果圖。 第5圖(a)係顯示傾斜基板來控制透磁率面內指向性 之範例圖;(b )係顯示蒸鍍源與基板及基板傾斜角度圖; (c)係顯示μ之測定方向圖。 第6圖係顯示用於電磁雜訊抑制效果之驗證的槪略裝 置構成圖。 第7圖係顯示將基於本發明所製作之多數個電磁雜訊 吸收薄膜試樣置於微帶線路上時之反射特性S11圖。 第8圖係顯示將基於本發明所製作之多數個電磁雜訊 吸收薄膜試樣置於微帶線路上時之傳導特性S21圖。 第9圖(a)係已形成藉由本發明實例所得之電磁雜訊 吸收薄膜於接地線之能動元件封裝電路基板的上視圖: (b)係(a)之電磁雜訊吸收薄膜的側視圖。 第10圖係顯示第9圖(a)及(b)之電磁千涉吸收薄 膜的放射雜訊減低效果圖。The degree of radio-magnetic noise observed at -16- 1326886 is greatly attenuated by the degree of radiated electromagnetic noise compared to the electromagnetic noise absorbing film not provided with the comparative example shown by the dashed curve 76. 'Inferred that an effective electromagnetic noise reduction effect can be obtained. In the example of the present invention described above, an example of providing an electromagnetic noise absorbing film on a circuit board on which an active device is mounted, for example, on a ground line, is described. The high-frequency current flowing portion, for example, a metal frame, which is provided on an electronic component including the same circuit board, a part of the data line, the active component, or an electronic component having the active component, can of course obtain an electronic noise reduction effect. As described above, the electromagnetic noise absorbing film according to the embodiment of the present invention has excellent magnetic permeability characteristics at high frequencies, particularly imaginary magnetic permeability characteristics, and the electromagnetic noise absorbing film using the electromagnetic noise absorbing film has a high The excellent noise absorption effect in the frequency is extremely effective for the control of high frequency electromagnetic noise which has become a problem in recent years. Moreover, according to the present invention, it is possible to provide an electromagnetic noise absorbing film comprising a fine particle structure film which suppresses super-magnetic properties and which has improved electrical resistance and can control a rotational resonance phenomenon. INDUSTRIAL APPLICABILITY The electromagnetic noise absorbing film according to the present invention can be controlled to be a high frequency current of noise, and can be used for an electronic device or an electric machine starting from a personal computer, a mobile terminal, or the like. (5) Brief description of the drawings: Fig. 1(a) shows the electron microscopy of the particles produced by the sputtering method [S 3 -17- 1326886 structure (300 ° C, heat treatment for 1 hour) on the inner surface of the film. Photograph; (b) An electron micrograph of the columnar structure produced by vapor deposition observed in the cross section of the film. Fig. 2 is a graph showing the frequency characteristics of the permeability of the film; (a) and (b) show the frequency characteristics of the permeability of the vapor deposited film and the sputter film. Fig. 3 is a graph showing the relationship between the magnetic permeability and the resonance frequency which are controlled by changing the shutter time. Fig. 4 is a graph showing the results of magnetic permeability measurement in the case where the shutter time is changed from 10 seconds to 200 seconds to show a sample. Fig. 5(a) is a view showing an example of slanting a substrate to control the in-plane directivity of permeability; (b) showing an angle of inclination of a vapor deposition source, a substrate, and a substrate; (c) showing a measurement pattern of μ. Fig. 6 is a view showing a configuration of a schematic device for verification of an electromagnetic noise suppression effect. Fig. 7 is a view showing a reflection characteristic S11 of a case where a plurality of electromagnetic noise absorbing film samples produced based on the present invention are placed on a microstrip line. Fig. 8 is a view showing the conduction characteristic S21 of a case where a plurality of electromagnetic noise absorbing film samples produced based on the present invention are placed on a microstrip line. Fig. 9(a) is a top view of the active component package circuit board on which the electromagnetic noise absorbing film obtained by the present invention is formed on the ground line: (b) A side view of the electromagnetic noise absorbing film of the system (a). Fig. 10 is a view showing the effect of reducing the radiation noise of the electromagnetic interference absorption film of Figs. 9(a) and (b).
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