200540883 玖、發明說明： 【發明所屬之技術領域】 本發明係關於一種過電流保護元件及其製作方法，特別 是關於一種具有正溫度係數（Posltlve Temperature200540883 发明 Description of the invention: [Technical field to which the invention belongs] The present invention relates to an overcurrent protection element and a manufacturing method thereof, and more particularly to a device having a positive temperature coefficient (Posltlve Temperature
Coefficient; PTC)特性之過電流保護元件及其製作方法。 【先前技術】 習知之PTC元件之電阻值對溫度變化的反應相當敏銳。 當PTC兀件於正常使用狀況時，其電阻可維持極低值而使 電路得以正常運作。但是當發生過電流或過高溫的現象而 使溫度上升至一臨界溫度時，其電阻值會瞬間彈跳至一高 電阻狀態（例如104〇hm以上）而將過量之電流反向抵銷， 以達到保護電池或電路元件之目的。由於pTC元件可有效 地保護電子產品，因此該PTC元件已見整合於各式電路元 件中，以防止過電流的損害。 參照圖1(a)及1(b)，傳統之過電流保護元件的製作係將 兩電極箱11直接與一 PTC材料層12進行熱壓合（h〇t press)，而形成一過電流保護元件1〇。該兩電極箔丨丨可另 連接導線（未圖式）以串接至欲保護之電氣裝置，以防止 過電流所導致的損害。參照圖1(c)及圖1(d)，若應用表面 黏著元件（Surface Mounted Device ; SMD )之製程，該過 電流保護元件10可再藉由蝕刻該電極箔以形成缺口 15，並 利用玻纖環氧樹酯基層（Pre-Preg) 13及外電極層14等步 驟而完成一 SMD型式之過電流保護裝置。由於該後續之製 程與本發明並無直接相關，在此加以省略。 H:\Hu\tys\聚鼎科技中說丨〇\9〇〇1 〇如 -6- 200540883 «亥兩电極泊1 1及PTC材料層12壓合時必須施加 以上之/皿度。g] PTC材料相較於金屬具有較大的熱膨服係 數，而於加熱後常有熱應力（thermal stress)殘留於該過 電流保護it件1〇中。另外，於壓合過程中，外力的施加亦 將使得該電極fg U及PTC材料層12產生變形，而更加凸 顯殘留應力（residual stress )的問題。 隨者電氣產品小型化發展，過電流保護元件之微小化亦 是當丽必然的趨勢。當元件尺寸由〇8〇5 (長乂寬）規袼縮小 至0603規格時，其厚度必須相對地減小。然而，因習知之 過電流保護元件係採用高熱壓合，容易於該pTC材料層12 之表面形成皺折甚或損壞。目前避免上述問題產生的實務 作法係選用較厚之PTC材料層12及電極箔n，但此舉將 使得該過電流保護元件1〇之厚度達1〇〇微米（pm)以上， 而不適用於日趨小型化的電子裝置。 【發明内容】 本發明之目的係提供一種過電流保護元件及其製作方 法，可減少元件於製作過程中所產生的殘留應力，且具有 較薄之外型而適用於小尺寸或包含多層PTC材料之過電流 保護元件，以達到降低常態電阻及耐高電壓之特性。 為達到上述目的，本發明揭示一種過電流保護元件，其 包含兩電極層、一 PTC材料層及至少一導電層，其中該過 電流保護元件係一層疊結構，該PTC材料層與兩電極層係 分別設於内、外，該至少一導電層嵌合於該PTC材料層之 表面且豐設於該PTC材料層和至少一該電極層之間，以作 H:\Hu\tysW 鼎科技中說\900 丨 0\900 丨 0.doc 200540883 為導電及連接之用。 上述之過電流保護元件可利用 广幻万去製作··首先提供 一 PTC材料層，並於該PTC材料芦之矣 何1·十層之表面利用電漿形成粗 以濺鍍（sputtedng)等非電沈積法形成至少 一導電層。之後，再利用電鍍（electroplating)或其他之 電沈積（eleetrode—tion)法形成至少—電極層於該至少 一導電層表面。 實際上，該PTC材料層亦可不經由電聚形成粗棱面，而 直接以濺鍍等非電沈積法形成至少一導電層。但若PTC材 料層具有粗糙面可增加其與該至少一導電層間之結合強 度，進而減少電極層剝離（peeling)的機率。 該導電層之主要目的係作為後續利用電錢或其他電沈積 法形成該電極層時導電之用。此外，#由控制電漿強度或 作用時間，可調整該PTC材料層之表面粗财，而控㈣ 鍍之製程參數則可調整導電層之厚度以符合所需。 本發明係利用電鍍或其他電沈積法製作該電極層，故不 需經過壓合之高溫製程，而可大幅減低元件中的殘留應 力。此外，本發明特別適用於SMD製程以製作小尺寸（例 如符合0605或0402規袼）或包含多層PTC材料之過電流 保護元件。藉由並聯多層之PTC材料，可獲得耐高電壓的 效果0 【實施方式】 圖2(a)至2(c)例示本發明之過電流保護元件之製作方 法。請參照圖2(a)及2(b)，於一 PTC材料層21之表面利 旧_齊鼎科技中r#90010\900i0d〇c 200540883 用電漿及濺鍍等方法形成一嵌合於該PTC材料層2丨表面 之導電層22,以作為後續電沈積時導電之用。藉由電漿的 離子轟擊（ion bombardment )，該PTC材料層21之表面 可形成粗糙面，該導電層22則隨後覆蓋於該pTC材料層 21之表面。該導電層22之材質可選自銀、鎳、鋁、鈦及 鎳鉻合金等，其厚度則介於50埃至5000埃。藉由調整電 漿的強度及時間，即可彈性調整介面的粗糙度 (roughness)，而調整濺鍍之製程參數則可控制該導電層 22之厚度。為因應元件小型化的趨勢及降低元件的常態電 阻，该PTC材料層21將愈來愈薄。若介面的粗糙度過大， 了月b使付兩、電層2 2間於某處距離過小，而容易於兩導電 層22間發生短路的現象。本發明可依情況調整出最適合之 粗糙度以解決上述之短路的問題。參照圖2(c)，利用電鍍 或其他之電沈積法於該導電層22之表面形成電極層23, 而形成一過電流保護元件2〇。該電極層23之材質可選自 鎳、銅或其合金，其厚度則介於〇·3米爾（mil)至3米爾。 傳統上使用整片電極箔壓合的方式因受限於電極箔本身 的更度及尺寸’其過電流保護元件之微小化的瓶頸難以突 破。本發明之過電流保護元件2〇係利用電沈積法製作，原 則上並無尺寸大小的限制，而可做得相當小，特別適合於 J尺寸SMD型式之過電流保護元件。該過電流保護元件 T再依據已知之SMD製程覆蓋上pre_preg材料、覆蓋 外電極層、#刻、利用電鑛於孔（piating Th_gh ·, PTH )形成導電通孔等步驟，製作出smd型式之過電流保 H:\Hu\tys\聚鼎科技中說\9001 〇\9〇〇 1 〇 d〇c 200540883 護元件。因上述關於SMD之後續製程為習知，在此不再詳 述〇 本發明之另一實施例如圖3(>)至3(c)所示，其係應用於 SMD製程。參照圖3(勾，首先可於一 pTC材料層Μ之表 面形成罩幕（mask)層34。參照圖3(b)，經電漿或濺鍍等 方法嵌入兩導電層32於該PTC材料層31表面，並利用電 鍍或其他電沈積法形成兩電極層33於該兩導電層32之表 面。參恥圖3(c)，被該罩幕層34覆蓋之pTC材料層31之 表面在去除該罩幕層34後將可呈現複數個缺口 35。應用_ 本實施例之方法可自然形成缺口 35，而得以省略SMd製 程中蝕刻電極層之步驟。 本發明相較於習知技術具有如下之優點·· 1 ·利用電沈積法製作不需施加高熱，# pTc材料可於室溫 或略冋於至溫下製作，故可大幅降低製程中所產生的殘 留應力。Coefficient (PTC) overcurrent protection element and its manufacturing method. [Prior art] The resistance value of the conventional PTC element is quite sensitive to temperature changes. When the PTC element is in normal use, its resistance can be kept very low and the circuit can operate normally. However, when the over-current or over-temperature phenomenon occurs and the temperature rises to a critical temperature, its resistance value will instantly bounce to a high-resistance state (for example, more than 104 hm), and the excess current will be reversely offset to achieve The purpose of protecting batteries or circuit components. Since the pTC element can effectively protect electronic products, the PTC element has been integrated into various circuit elements to prevent damage from overcurrent. Referring to FIGS. 1 (a) and 1 (b), the traditional manufacturing of an overcurrent protection element is to directly press the two electrode boxes 11 and a PTC material layer 12 by hot pressing to form an overcurrent protection. Element 10. The two electrode foils can be connected to wires (not shown) in series to the electrical device to be protected to prevent damage caused by overcurrent. Referring to FIG. 1 (c) and FIG. 1 (d), if a process of surface mounting device (SMD) is applied, the overcurrent protection element 10 can be etched to form a notch 15 by etching the electrode foil, and a glass substrate is used. Fiber epoxy resin base layer (Pre-Preg) 13 and external electrode layer 14 and other steps to complete an SMD type overcurrent protection device. Since this subsequent process is not directly related to the present invention, it is omitted here. H: \ Hu \ tys \ Juding Technology said 丨 〇 \ 9〇〇1〇 Such as -6- 200540883 «Hai two electrode Po 11 and PTC material layer 12 must be pressed when the above / / degree. g] PTC material has a larger thermal expansion coefficient than metal, and thermal stress often remains in the overcurrent protection device 10 after heating. In addition, during the pressing process, the application of external force will also cause the electrode fg U and the PTC material layer 12 to deform, and the problem of residual stress will be more prominent. With the development of miniaturization of electrical products, the miniaturization of overcurrent protection components is also an inevitable trend of Dangli. When the component size is reduced from 0805 (length to width) to 0603 size, its thickness must be relatively reduced. However, because the conventional overcurrent protection element uses high thermal compression bonding, it is easy to form wrinkles or even damage the surface of the pTC material layer 12. The current practice to avoid the above problems is to choose a thicker PTC material layer 12 and electrode foil n, but this will make the thickness of the overcurrent protection element 10 more than 100 microns (pm), which is not suitable for Increasingly miniaturized electronic devices. [Summary of the Invention] The object of the present invention is to provide an overcurrent protection element and a manufacturing method thereof, which can reduce the residual stress generated during the manufacturing process of the element, and has a thin profile and is suitable for a small size or contains multiple PTC materials Over-current protection element to reduce the normal resistance and high voltage resistance. To achieve the above object, the present invention discloses an overcurrent protection element including two electrode layers, a PTC material layer, and at least one conductive layer, wherein the overcurrent protection element has a laminated structure, and the PTC material layer and the two electrode layer system Located at the inner and outer sides, the at least one conductive layer is fitted on the surface of the PTC material layer and is provided between the PTC material layer and at least one of the electrode layers for H: \ Hu \ tysW. \ 900 丨 0 \ 900 丨 0.doc 200540883 is used for conducting and connecting. The above-mentioned overcurrent protection element can be manufactured by Guanghuanwan .. First, a PTC material layer is provided, and the surface of the PTC material Lu Zhihe 1. 10 layers is formed by plasma to form non-sputted and non-sputted An electrodeposition method forms at least one conductive layer. After that, at least an electrode layer is formed on the surface of the at least one conductive layer by electroplating or other electrodeposition methods. In fact, the PTC material layer can also be formed into a rough edge without using electropolymerization, and at least one conductive layer can be directly formed by a non-electrodeposition method such as sputtering. However, if the PTC material layer has a rough surface, the bonding strength between the PTC material layer and the at least one conductive layer can be increased, thereby reducing the probability of peeling of the electrode layer. The main purpose of the conductive layer is to conduct electricity when the electrode layer is subsequently formed using electric money or other electrodeposition methods. In addition, # by controlling the strength or duration of the plasma, the surface roughness of the PTC material layer can be adjusted, and the process parameters of the ㈣ plating process can adjust the thickness of the conductive layer to meet the needs. In the present invention, the electrode layer is fabricated by using electroplating or other electrodeposition methods, so that it does not need to go through a high temperature process of lamination, and can greatly reduce the residual stress in the device. In addition, the present invention is particularly applicable to SMD processes to produce over-current protection elements of small size (e.g., complying with 0605 or 0402 regulations) or containing multilayer PTC materials. By connecting multiple layers of PTC materials in parallel, the effect of withstanding high voltage can be obtained. [Embodiment] Figs. 2 (a) to 2 (c) illustrate a method for manufacturing the overcurrent protection element of the present invention. Please refer to Figures 2 (a) and 2 (b). On the surface of a PTC material layer 21, the surface is old_ Qiding Technology r # 90010 \ 900i0d〇c 200540883 using a plasma and sputtering method to form a fit in the The conductive layer 22 on the surface of the PTC material layer 2 is used for conducting electricity during subsequent electrodeposition. By ion bombardment of the plasma, the surface of the PTC material layer 21 can form a rough surface, and the conductive layer 22 then covers the surface of the pTC material layer 21. The material of the conductive layer 22 may be selected from silver, nickel, aluminum, titanium, and nickel-chromium alloy, and the thickness thereof is between 50 angstroms and 5000 angstroms. By adjusting the intensity and time of the plasma, the roughness of the interface can be flexibly adjusted, and the thickness of the conductive layer 22 can be controlled by adjusting the sputtering process parameters. In response to the trend of miniaturization of the device and reduction of the normal resistance of the device, the PTC material layer 21 will become thinner and thinner. If the roughness of the interface is too large, the distance between the two electric layers 22 and the electric layer 22 is too small in some cases, and it is easy to cause a short circuit between the two conductive layers 22. According to the present invention, the most suitable roughness can be adjusted to solve the above short circuit problem. Referring to FIG. 2 (c), an electrode layer 23 is formed on the surface of the conductive layer 22 by electroplating or other electrodeposition methods to form an overcurrent protection element 20. The material of the electrode layer 23 may be selected from nickel, copper or an alloy thereof, and the thickness thereof is between 0.3 mil and 3 mil. Traditionally, the method of using the entire electrode foil compression method is difficult to break through the bottleneck of miniaturization of the overcurrent protection element due to the limitation and size of the electrode foil itself. The overcurrent protection device 20 of the present invention is manufactured by electrodeposition method, and there is no restriction on size in principle, and it can be made relatively small, which is especially suitable for overcurrent protection devices of J size SMD type. The overcurrent protection element T is then covered with pre_preg material, covered with an external electrode layer, #etched, and electrically conductive vias (piating Th_gh ·, PTH) to form conductive vias according to a known SMD process. Current protection H: \ Hu \ tys \ Juding Technology said that \ 9001 〇 \ 〇〇〇〇〇〇〇 200540883 protection element. Since the above-mentioned subsequent process of SMD is known, it will not be described in detail here. Another embodiment of the present invention is shown in Figs. 3 (>) to 3 (c), which is applied to the SMD process. Referring to FIG. 3 (hook, first, a mask layer 34 can be formed on the surface of a pTC material layer M. Referring to FIG. 3 (b), two conductive layers 32 are embedded in the PTC material layer by plasma or sputtering. 31, and two electrode layers 33 are formed on the surfaces of the two conductive layers 32 by electroplating or other electrodeposition methods. Referring to FIG. 3 (c), the surface of the pTC material layer 31 covered by the cover layer 34 is removing the After the mask layer 34, a plurality of gaps 35 can be presented. Application _ The method of this embodiment can naturally form the gaps 35, so that the step of etching the electrode layer in the SMd process can be omitted. Compared with the conventional technology, the present invention has the following advantages ·· 1 · It does not need to apply high heat to produce by electrodeposition method. # PTc material can be produced at room temperature or slightly below temperature, so the residual stress generated in the process can be greatly reduced.
口 V電層係肷A PTC材料層，故具有相當良好的附著 I*生，、而電鍍亦可提升電極層與PTc材料層間之結合強度 及導電性’ $而提升元件開關（on-off )之可靠度 (reliability) 〇 3·可調整PTC元件表面夕由 干衣面之粗糙度，以避免兩電極層間發生 短路的現象。 可裝作較薄之過電流保護元件，以順應元件微小化的 勢。此外，本發明亦特別適用於SMD製程。 5.可選用較薄之PTC材料層’進而降低元件之電阻值， H:\Hu\tys\聚鼎科技中說\9〇〇丨⑽〇〇 1 〇d〇c -10- 200540883 6·因具有可製成薄型之特性，適於製作包含多層材料 之過電流保護元件。藉由並聯多層之PTC材料，可提高 其工作電壓，而具有耐高電壓之特性。 7·製程較簡單，可降低製造成本。 本發明之技術内容及技術特點已揭示如上，然而熟悉本 項技術之人士仍可能基於本發明之教示及揭示而作種種不 月離本發明精神之替換及修飾。因此，本發明之保護範圍 應不限於實施例所揭示者，而應包括各種不背離本發明之 替換及修飾，並為以下之申請專利範圍所涵蓋。 【圖式簡單說明】 圖1(a)至1(d)顯示習知之過電流保護元件之製作流程； 圖2(a)至2(c)顯示本發明之一較佳實施例之過電流保護 元件之製作流程；以及 圖3(a)至3(c)顯示本發明之另一較佳實施例之過電流保 護元件之製作流程。 【元件符號說明】 10 過電流保護元件 11 電極箔 12 PTC材料層 13 披覆陶瓷積層 14 外電極層 15 缺口 20 過電流保護元件 21 PTC材料層 22 導電層 23 電極層 31 PTC材料層 32 導電層 33 電極層 34 罩幕層 35 缺口 HAHiAtysHA 鼎科技中說\90010\900l0.doc - 11 -The V electrical layer is a PA PTC material layer, so it has a very good adhesion, and electroplating can also improve the bonding strength and conductivity between the electrode layer and the PTC material layer, and increase the on-off of the component. Reliability 〇3. The roughness of the surface of the PTC element can be adjusted to avoid the short circuit between the two electrode layers. Can be installed as a thinner overcurrent protection element to meet the trend of component miniaturization. In addition, the invention is also particularly suitable for SMD processes. 5. A thinner layer of PTC material can be used to reduce the resistance value of the device, H: \ Hu \ tys \ Juding Technology said \ 9〇 丨 ⑽〇〇1 〇d〇c -10- 200540883 6 · Cause It can be made into a thin type, which is suitable for making overcurrent protection elements including multiple layers of materials. By connecting multiple layers of PTC materials in parallel, the operating voltage can be increased, and it has the characteristics of withstanding high voltage. 7. The manufacturing process is simpler, which can reduce manufacturing costs. The technical content and technical features of the present invention have been disclosed as above. However, those skilled in the art may still make various substitutions and modifications based on the teaching and disclosure of the present invention without departing from the spirit of the present invention. Therefore, the protection scope of the present invention should not be limited to those disclosed in the embodiments, but should include various substitutions and modifications that do not depart from the present invention, and are covered by the following patent application scope. [Schematic description] Figures 1 (a) to 1 (d) show the manufacturing process of a conventional overcurrent protection element; Figures 2 (a) to 2 (c) show the overcurrent protection of a preferred embodiment of the present invention The manufacturing process of the device; and FIGS. 3 (a) to 3 (c) show the manufacturing process of the overcurrent protection device according to another preferred embodiment of the present invention. [Description of element symbols] 10 Overcurrent protection element 11 Electrode foil 12 PTC material layer 13 Covered with ceramic laminate 14 External electrode layer 15 Notch 20 Overcurrent protection element 21 PTC material layer 22 Conductive layer 23 Electrode layer 31 PTC material layer 32 Conductive layer 33 electrode layer 34 cover layer 35 notch HAHiAtysHA said in Ding Technology \ 90010 \ 900l0.doc-11-