201223750 六、發明說明： 【發明所屬之技術領域】 本發明係關於一種貼金屬層合板’詳細而言’係關於 一種具有液晶聚合物層，且高頻電氣特性優異之貼金屬層 合板。 【先前技術】 目前，電子機器大多因小型化、輕量化而使機器內部 的空間受限，因此多使用有可將配線或基板彎曲之可撓性 電路基板（以下簡稱FPC)。再者，最近，隨著機器的高 性能化，而使對傳送訊號之高頻化的對應成爲必須。 以往，在MHz程度的動作速度所使用的電子電路中， FPC係只要將應連接的配線，正確地在基板上配線，動作 便不會產生問題.。但是，若電子電路的動作速度變快，則 僅在上述要求的條件下便會變得不充分，因此FPC也必須 對應高頻化。 若於訊號的傳送路徑存在會改變阻抗的點，則在該點 會產生電磁波的反射，而產生電氣訊號遺失或訊號波形紊 亂等的缺陷。因此，爲了高頻訊號的傳送或是長距離傳送 ’必須使FPC之特性阻抗與機器本體電路之阻抗匹配。 特性阻抗，係以介電體的介電率、介電體厚度、電路 厚度、電路線寬的函數所表示，於阻抗匹配中，必須特別 將影響較大的介電體厚度增厚，並且使厚度公差減少。一 般而言，係使用將介電體厚度公差小的聚醯亞胺製膜成厚 _ -5- 201223750 度38〜50 μιη的貼銅層合板來進行阻抗匹配。然而，聚醯亞 胺，係吸濕率、介電損失較大，作爲在今後進展之GHz帶 的高頻基板之材料使用上，並不具有充分的電氣特性。 於傳送頻數之高頻化爲必須時，就對應於高頻之代表 性的基板而言，適合使用以液晶聚合物作爲基材層的電路 基板。液晶聚合物，係以低介電率、低介電損失爲特徵之 樹脂，與使用其他樹脂作爲絕緣層的情況相比較，使用相 同樹脂作爲絕緣層之電路基板，係具有使高頻領域之傳送 損失減少的效果。 再者，於高頻領域之特性阻抗的控制中，就適用薄膜 厚度公差少的液晶聚合物之貼金屬層合板而言，係可列舉 專利文獻1所示的基板材料。該文獻中所記載之層合板， 雖爲了提高液晶聚合物薄膜與金屬箔之間的層間接著強度 (黏著強度）’對於金屬箱與液晶聚合物接觸的面，以使 表面粗糙度Rz增大爲2.5〜4.Ομιη的方式形成突起物並進行 粗化處理’但仍有於高頻領域中訊號之傳送特性不充分的 問題。 另一方面’在製造具有液晶聚合物層之貼金屬層合板 時，一般而言，提案有下述方法：以生產性高的輥對輕方 式來搬送形成液晶聚合物層的液晶聚合物薄膜與金屬箔之 層合板，並邊加熱邊通過一對的加壓軋輥之間進行連續地 熱壓接。於該方法中，雖因熱壓接而與金屬箔充分地密著 ，但爲了維持層合板的尺寸特性，必須在層合時使液晶聚 合物分子之流動性，在受到抑制的同時進行熱壓接，而使 -6 - 201223750 維持液晶聚合物層之厚度公差的熱壓接條件成爲必要。 〔先前技術文獻〕 〔專利文獻〕 [專利文獻1]日本特開20〇5-219379號公報 【發明內容】 〔發明所欲解決之課題〕 本發明之目的’係提供一種爲了對應傳送訊號之高頻 化’將會導致特性阻抗公差的介電體厚度公差縮小，且於 高頻領域中訊號之傳送損失小的貼金屬層合板。 〔解決課題之手段〕 本發明者們發現，爲了達成上述目的，以液晶聚合物 作爲介電體層之貼金屬層合板中，於液晶聚合物層使用厚 度公差較小的薄膜，且，將金屬箔之表面凹凸形狀縮小， 藉此’得到於高頻領域中特性抗阻匹配與低傳送損失並存 的電路基板，而完成本發明。 亦即，本發明之要旨係如下所述。 (1 ) 一種貼金屬層合板，其係於液晶聚合物層之單 面或兩面具有金屬筢，其特徵爲：金屬箔，係將與液晶聚 合物層接觸的面粗化處理而於表層部具有突起物，以突起 物的高度Η相對於該突起物之根部的寬度L之比所表示的縱 橫比（H/L )爲3〜20之範圍，並且突起物的高度爲0.1〜 2μιη之範圍，液晶聚合物層，係具有1〇〜200μιη之厚度， 201223750 且膜厚公差未達6%。 (2 )如（1 )所記載之貼金屬層合板，其中實 處理之金屬箔的面之表面粗糙度Rz爲0.3 μηι以上未I 〇 (3 )如（1 )或（2 )所記載之貼金屬層合板 將形成液晶聚合物層之液晶聚合物薄膜與金屬箔， 的金屬加壓軋輥間進行加熱壓接所得。 (4 )如（3 )所記載之貼金屬層合板，其中液 物薄膜的熱變形溫度在260〜350 °C之範圍。 (5 )如（1 )〜（4 )中任一項所記載之貼金 板，其中於常溫中金屬箔與液晶聚合物層之18 0層 強度爲0.5〜5kN/m。 〔發明效果〕 依據本發明之貼金屬層合板，可於高頻領域中 抗匹配與低傳送損失並存，液晶聚合物層與金屬箔 密著性優異，且可滿足高頻用電路所要求的品質。 〔實施發明之最佳形態〕 以下，將針對本發明之實施形態進行詳細地說 於形成液晶聚合物層之液晶聚合物，係以僅由 族液晶聚合物，亦即，不含脂肪族長鏈之實質的芳 構成之液晶聚合物爲佳，再者，其中以如下述式 示，由6-烴基-2-萘甲酸與對烴苯甲酸所成之聚酯爲 -δ 施粗化 | 2.5 μιη ，其係 在對 晶聚合 屬層合 間剝離 特性阻 之層間 全芳香 香族所 1 )所 更佳》 ε 201223750 另外’下述式中之m及η’係表示各構成單位之存在莫耳比 的正數。 【化1】201223750 6. TECHNOLOGICAL FIELD OF THE INVENTION The present invention relates to a metal-clad laminate [detailed] relating to a metal-clad laminate having a liquid crystal polymer layer and excellent in high-frequency electrical characteristics. [Prior Art] At present, electronic devices are often limited in size and weight, and the space inside the device is limited. Therefore, a flexible circuit board (hereinafter referred to as FPC) capable of bending wiring or a substrate is often used. Furthermore, recently, as the performance of the device has increased, it has become necessary to respond to the high frequency of the transmission signal. Conventionally, in an electronic circuit used for an operating speed of a degree of MHz, the FPC system does not have a problem in that the wiring to be connected is correctly wired on the substrate. However, if the operating speed of the electronic circuit is fast, it will be insufficient under the above-mentioned required conditions, and therefore the FPC must also be high-frequency. If there is a point at the signal transmission path that changes the impedance, electromagnetic wave reflection occurs at this point, which causes defects such as loss of electrical signals or turbulence of the signal waveform. Therefore, in order to transmit high-frequency signals or long-distance transmission, the characteristic impedance of the FPC must be matched with the impedance of the machine body circuit. The characteristic impedance is expressed by a function of the dielectric constant of the dielectric, the thickness of the dielectric, the thickness of the circuit, and the line width of the circuit. In the impedance matching, the thickness of the dielectric having a large influence must be particularly thickened, and Thickness tolerances are reduced. In general, a copper-clad laminate having a thickness of _ -5 - 201223750 degrees 38 to 50 μm is formed by using a polyimide having a small dielectric thickness tolerance to perform impedance matching. However, polybenzamine has a large moisture absorption rate and a dielectric loss, and does not have sufficient electrical characteristics as a material for use in a high-frequency substrate of a GHz band which is progressing in the future. When the high frequency of the transmission frequency is necessary, it is suitable to use a liquid crystal polymer as a substrate layer for a substrate corresponding to a high frequency. The liquid crystal polymer is a resin characterized by a low dielectric constant and a low dielectric loss, and a circuit substrate using the same resin as an insulating layer has a high frequency field transmission as compared with a case where another resin is used as the insulating layer. The effect of loss reduction. In addition, in the control of the characteristic impedance of the high-frequency field, the substrate material shown in Patent Document 1 is used for the metal-clad laminate of the liquid crystal polymer having a small film thickness tolerance. In order to increase the interlayer adhesion strength (adhesive strength) between the liquid crystal polymer film and the metal foil, the laminate having the surface roughness Rz is increased in order to increase the interlayer adhesion strength (adhesion strength) between the liquid crystal polymer film and the metal foil. 2.5~4. Ομιη forms a protrusion and performs roughening treatment. However, there is still a problem that the transmission characteristics of the signal are insufficient in the high frequency field. On the other hand, when manufacturing a metallized laminate having a liquid crystal polymer layer, generally, there is proposed a method of transporting a liquid crystal polymer film forming a liquid crystal polymer layer in a light manner by a highly productive roll. The laminate of metal foil is continuously thermocompression bonded between a pair of press rolls while heating. In this method, although it is sufficiently adhered to the metal foil by thermocompression bonding, in order to maintain the dimensional characteristics of the laminate, it is necessary to cause the fluidity of the liquid crystal polymer molecules at the time of lamination to be hot-pressed while being suppressed. It is necessary to make the thermocompression bonding condition of -6 - 201223750 maintaining the thickness tolerance of the liquid crystal polymer layer. [PRIOR ART DOCUMENT] [Patent Document 1] Japanese Laid-Open Patent Publication No. Hei 20-219379. SUMMARY OF THE INVENTION [Problems to be Solved by the Invention] The object of the present invention is to provide a high level for corresponding transmission signals. "Frequency" will result in a reduction in the dielectric thickness tolerance of the characteristic impedance tolerance, and in the high frequency field, the signal transmission loss is small and the metal laminate is low. [Means for Solving the Problems] The present inventors have found that in order to achieve the above object, in a metal-clad laminate in which a liquid crystal polymer is used as a dielectric layer, a film having a small thickness tolerance is used for a liquid crystal polymer layer, and a metal foil is used. The surface unevenness shape is reduced, whereby the present invention is completed by obtaining a circuit substrate in which a characteristic resistance matching and a low transmission loss coexist in a high frequency field. That is, the gist of the present invention is as follows. (1) A metal-clad laminate having a metal crucible on one side or both sides of a liquid crystal polymer layer, characterized in that a metal foil is obtained by roughening a surface in contact with a liquid crystal polymer layer and having a surface layer portion The aspect ratio (H/L) expressed by the ratio of the height Η of the protrusion to the width L of the root of the protrusion is in the range of 3 to 20, and the height of the protrusion is in the range of 0.1 to 2 μm. The liquid crystal polymer layer has a thickness of 1 〇 to 200 μm, 201223750 and a film thickness tolerance of less than 6%. (2) The metal-clad laminate according to (1), wherein the surface roughness Rz of the surface of the metal foil to be treated is 0.3 μηι or more, and I 〇(3) is as described in (1) or (2) The metal laminate is obtained by heat-compression bonding between a liquid crystal polymer film in which a liquid crystal polymer layer is formed and a metal foil. (4) The metal-clad laminate according to (3), wherein the heat distortion temperature of the liquid film is in the range of 260 to 350 °C. (5) The gold plate according to any one of (1) to (4) wherein the strength of the 18-layer of the metal foil and the liquid crystal polymer layer at room temperature is 0.5 to 5 kN/m. [Effect of the Invention] According to the metal-clad laminate of the present invention, the anti-matching and the low transmission loss can be coexisted in the high-frequency field, and the liquid crystal polymer layer and the metal foil are excellent in adhesion and can satisfy the quality required for the high-frequency circuit. . BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a liquid crystal polymer in which a liquid crystal polymer layer is formed in detail according to an embodiment of the present invention is a liquid crystal polymer only, that is, an aliphatic long chain is not contained. A substantially aromatic liquid crystal polymer is preferred, wherein, as shown by the following formula, the polyester formed from 6-hydrocarbyl-2-naphthoic acid and para-hydrobenzoic acid is -δ roughened | 2.5 μιη, It is more preferable that the layer is a wholly aromatic aromatic group in the case of the peeling property resistance between the layers of the crystal polymerization. ε 201223750 In addition, m and η in the following formula indicate the positive number of the molar ratio of each constituent unit. . 【化1】
液晶聚合物，係在耐熱性、加工性之觀點，以具有對 光學向異性之溶融相的轉移溫度在200〜400 °C之範圍內， 特別是2 5 0〜3 5 之範圍內者爲佳。此外，對於形成液晶 聚合物層之液晶聚合物，在不損及其特性的範圍內，亦可 調配例如滑劑、抗氧化劑、充塡劑等。 就將液晶聚合物薄膜化而形成液晶聚合物層的方法而 言，係可列舉例如·· T模法、疊層延伸法、充氣法等。於 充氣法或疊層延伸法中，由於不僅對薄膜的機械軸方向（ MD方向），也對與其垂直的方向（TD方向）施加應力， 因此可得在MD方向與TD方向中能取得機械性質之平衡的 薄膜。 液晶聚合物層的厚度範圍爲10〜200μιη，較佳爲25〜 ΙΟΟμηι。液晶聚合物層的厚度，若未達ΙΟμΓη，則由於容易 破裂而使處理變得困難。此外，液晶聚合物層，係爲了取 得特性阻抗匹配，相對於厚度使膜厚公差在6%以內，較佳 爲使膜厚公差在5 %.以內。在此，相對於液晶聚合物層的厚 -9 - 201223750The liquid crystal polymer is preferably in the range of 200 to 400 ° C, particularly in the range of 2 5 0 to 3 5 , in terms of heat resistance and workability, and the transition temperature of the melt phase having optical anisotropy is in the range of 200 to 400 ° C. . Further, for the liquid crystal polymer forming the liquid crystal polymer layer, for example, a lubricant, an antioxidant, a smear, or the like may be blended in a range which does not impair the properties thereof. In the method of forming a liquid crystal polymer layer by thinning a liquid crystal polymer, for example, a T-die method, a lamination stretching method, an aeration method, or the like can be given. In the inflation method or the lamination stretching method, since stress is applied not only to the mechanical axis direction (MD direction) of the film but also to the direction perpendicular thereto (TD direction), mechanical properties can be obtained in the MD direction and the TD direction. Balanced film. The thickness of the liquid crystal polymer layer ranges from 10 to 200 μm, preferably from 25 to ΙΟΟμη. If the thickness of the liquid crystal polymer layer is less than ΓμΓη, handling is difficult due to easy cracking. Further, in order to obtain the characteristic impedance matching, the liquid crystal polymer layer has a film thickness tolerance of 6% or less with respect to the thickness, and preferably has a film thickness tolerance of 5% or less. Here, the thickness relative to the liquid crystal polymer layer -9 - 201223750
度’膜厚公差爲所測量的厚度數據之標準偏差乘以3倍所 求得的値。上述液晶聚合物層係可使用市售之液晶聚合物 薄膜’例如可使用JAPAN GORE TEX股份有限公司製BIAC (註冊商標）等。 本發明使用之金屬箔的材質並無特別限制，可例示例 如金、銀、銅、不鏽鋼、鎳、鋁等。從導電性、處理的容 易性、價格等的觀點而言，適合使用銅箔或不銹鋼箔。銅 箔，亦可使用藉由壓延法或電解法所製造之任一者。 金屬箔的厚度，係可在以1〜ΙΟΟμιη爲佳，更佳爲5〜 7〇 μηι，特佳爲8〜20 μιη的範圍。將金屬箔的厚度減薄一事 ，雖於電路加工中容易形成精細圖型的觀點而言爲佳，但 若過薄，則除了於貼金屬層合板的製造步驟中容易在金屬 箔產生皺摺之外，於經電路加工之配線基板中也容易產生 配線的破斷，而有作爲配線基板之信賴性降低之虞。另一 方面，若過厚，則在將金屬箔蝕刻加工而形成電路時，容 易在電路側面形成錐形，而對精細圖型的形成產生不利。 於本發明中，重要的是將金屬箔表面粗化處理後的粗 化形狀（凹凸形狀）與其凹凸的高度。檢測表面凹凸的指 標，常使用的Rz係以.十點平均粗糙度所表示者，並以JIS B 0601爲依據而測量。但，Rz雖作爲金屬箔自身大的起伏 指標爲有效，但接觸端子的直徑較粗化處理所使用的突起 物更大，而無法表示藉由粗化處理所形成之突起物的尺寸 (凹凸形狀）。因此，於本發明中，就用來評估粗化處理 程度的指標而言，使用依據剖面觀察所得之突起物之根部 -10- 201223750 的寬度L、與突起物的高度Η，而規定金屬箔粗化面之突起 物的形狀。於剖面觀察的手法中，係以使藉由粗化處理而 形成在表層部的突起物之整體納入觀察視野中的方式，來 設定倍率並進行計測。另外，就金屬箔之粗化處理使用的 突起物而言，較佳爲可列舉由Cu、Ni、Co、Cr、Ζη、以 及Mo所組成群中所選出之1種金屬，或者是，含有由該群 中所選出之至少一種以上的元素之金屬合金。 於突起物之高度Η的計測中，係藉由金屬箔之剖面觀 察的手法，來測量從金屬箔母材與突起物之界面起到突起 物之頂點的高度。本發明所使用之金屬箔.，其突起物的高 度Η爲0.1〜2μιη之範圍，較佳爲Ο.ίμιη以上未達Ιμηι之範圍 °突起物的高度若超過2 μιη，則會發生於所得之貼金屬層 合板的高頻領域中傳送損失變大的問題。突起物的高度未 達〇_1μιη時，即使依據本發明也極難得到高密著強度，且 會發生在金屬箔加工時產生電路剝離，或在焊料等之熱處 理時膨脹或剝離等的問題。 突起物之縱橫比，係計測突起物之根部的寬度L，並 以突起物的高度Η相對於突起物之根部的寬度L之比（H/L )來計算。突起物之縱橫比爲3〜20之範圍，較佳爲3〜I5 之範圍。縱橫比若超過20，則突起物的形狀會變得過於銳 利，而導致突起物在藉由輥對輥之搬送時脫離，且有發生 層合板之刮痕等的外觀不良，或使配線間短路之虞。縱橫 比未達3時，突起物變得容易從樹脂層脫離，即使依據本 發明也極難得到高密著強度。另外，若將本發明使用的金 -11 · 201223750 屬箔之粗化處理的程度以Rz (十點平均粗糙度）來表示， 則實施粗化處理的金屬箔的面之表面粗糙度Rz，係以 0.3μιη以上未達2.5μπι爲佳，以〇.5μηι以上未達2.0μιη爲更佳 。金屬箔，係可從滿足上述要件之市售品中適當地選擇而 使用，其可例示例如JX Nippon Mining & Metals股份有限 公司製，商品名AMFN。 當由液晶聚合物薄膜形成液晶聚合物層時，從貼金屬 層合板之生產性的觀點而言，液晶聚合物薄膜與金屬箔， 係以皆使用捲筒狀者爲佳。如以下說明，將該等以輥對輥 連續地搬送，並藉由該過程來進行壓接，因此可藉由生產 性良好的製程而得到貼金屬層合板。 適合的貼金屬層合板之製造方法，係使液晶聚合物薄 膜與金屬箔重疊，並進行熱壓接來接著，而層合。從接合 狀態之均一性的觀點而言，熱壓接，係可使用無橡膠覆蓋 之一對的金屬加壓軋輥來作爲加壓軋輥。雖亦可使用經橡 膠覆蓋的金屬加壓軋輥，但此時，由於將覆蓋橡膠與金屬 軋輥接著的接著劑之耐熱性等的問題，而難以在250 °C以 上實施加壓軋輥加壓。因此，使用經橡膠覆蓋之金屬加壓 軋輥時，僅適用低熔點的液晶聚合物，結果，所得之貼金 屬層合板的耐熱性降低，且不具有焊接耐熱性。 金屬加壓軋輥的表面，必須藉由某些手段來加溫。該 手段並無特別限制’可例示藉由介電加熱方式或熱媒循環 方式所造成的加溫。另外，亦可列舉將加壓軋輥設置在恆 溫蓬蓋內或對軋輥表面吹熱風等的手法，且亦可倂用前述 -12- 201223750 手法。藉由上述手段，可將加壓軋輥的表面溫度相對於軋 輥的寬度方向設在8 °C以內，藉此可使金屬與液晶聚合物 層的剝離強度優異，且成爲變異較少的貼金屬層合板。此 外，藉由使用上述無橡膠覆蓋的金屬加壓軋輥，可簡便地 進行軋輥表面的加溫。金屬加壓軋輥的表面溫度，係可以 較液晶聚合物薄膜之熱變形溫度更低5〜1 00 °C之範圍內者 爲佳，更佳爲較液晶聚合物薄膜的熱變形溫度更低30〜90 °C的溫度。金屬加壓軋輥的表面溫度，若較液晶聚合物薄 膜的熱變形溫度更低超過1 〇〇 °C的溫度，則有薄膜與金屬 箔接著不充分的情形。此外，若使金屬加壓軋輥的表面溫 度，較液晶聚合物薄膜的熱變形溫度更低未達5 °C，則會 使壓接時薄膜的流動變得明顯，而成爲外觀不良的層合板 。另外，所謂液晶聚合物薄膜的熱變形溫度，係指使用熱 機械分析裝置，將供熱壓接的薄膜，以寬度2mm長度3 0mm ，夾具間距離15mm，且在荷重5g，昇溫速度5°C /分鐘的條 件下，對試驗片之長度方向的熱膨脹量作測量，並顯示其 反曲點（Inflection point)。此外，壓接時的壓力，雖只 要在可均勻地對寬度方向加壓的範圍內，便無特別限制， 但以5〜200kN/m爲佳，以70〜150kN/m爲更佳。 於本發明之層合板中，關於上述液晶聚合物層與金屬 箔的接著面，該接著面於常溫時，金屬箔與液晶聚合物層 之180°層間剝離強度係以0.5〜5kN/m以上爲佳，更佳爲〇.8 〜2·OkN/m 。The degree of film thickness tolerance is the 値 obtained by multiplying the standard deviation of the measured thickness data by three times. As the liquid crystal polymer layer, a commercially available liquid crystal polymer film can be used. For example, BIAC (registered trademark) manufactured by JAPAN GORE TEX Co., Ltd. can be used. The material of the metal foil used in the present invention is not particularly limited, and examples thereof include gold, silver, copper, stainless steel, nickel, aluminum, and the like. From the viewpoints of conductivity, handling ease, price, and the like, a copper foil or a stainless steel foil is suitably used. As the copper foil, any of those produced by calendering or electrolysis can also be used. The thickness of the metal foil may preferably be 1 to ΙΟΟμηη, more preferably 5 to 7 〇 μηι, and particularly preferably 8 to 20 μηη. It is preferable that the thickness of the metal foil is reduced, but it is preferable from the viewpoint of easily forming a fine pattern in circuit processing, but if it is too thin, wrinkles are easily formed in the metal foil in addition to the manufacturing step of the metallized laminate. In addition, in the wiring board processed by the circuit, breakage of the wiring is likely to occur, and reliability as a wiring board is lowered. On the other hand, if it is too thick, when the metal foil is etched to form a circuit, it is easy to form a taper on the side of the circuit, which is disadvantageous for the formation of a fine pattern. In the present invention, it is important that the roughened shape (concavo-convex shape) after roughening the surface of the metal foil and the height of the concavities and convexities. The index for detecting surface irregularities, which is commonly used, is expressed by a ten-point average roughness and is measured based on JIS B 0601. However, although Rz is effective as a large fluctuation index of the metal foil itself, the diameter of the contact terminal is larger than that of the protrusion used for the roughening treatment, and the size of the protrusion formed by the roughening treatment cannot be expressed (the uneven shape) ). Therefore, in the present invention, in terms of the index for evaluating the degree of roughening treatment, the width L of the root portion of the protrusion -10- 201223750 and the height Η of the projection are obtained by the cross section, and the metal foil is specified. The shape of the protrusion of the face. In the method of the cross-sectional observation, the magnification is set and the measurement is performed so that the entire projection formed on the surface layer portion by the roughening treatment is included in the observation field. In addition, as for the protrusion used for the roughening treatment of the metal foil, one selected from the group consisting of Cu, Ni, Co, Cr, Ζ, and Mo is preferable, or a metal alloy of at least one or more elements selected from the group. In the measurement of the height Η of the projections, the height from the interface between the metal foil base material and the projections to the apex of the projections was measured by the observation of the cross section of the metal foil. In the metal foil used in the present invention, the height Η of the protrusions is in the range of 0.1 to 2 μm, preferably Ο. ίμιη or more does not reach the range of Ιμηι. If the height of the protrusion exceeds 2 μm, it may occur in the obtained The problem of large transmission loss in the high frequency field of metal-clad laminates. When the height of the projections is less than 〇_1μηη, even in accordance with the present invention, it is extremely difficult to obtain high adhesion strength, and there is a problem that circuit peeling occurs during metal foil processing, or expansion or peeling occurs during heat treatment such as solder. The aspect ratio of the projections is calculated by measuring the width L of the root portion of the projections and the ratio (H/L) of the height Η of the projections to the width L of the roots of the projections. The aspect ratio of the protrusions is in the range of 3 to 20, preferably in the range of 3 to I5. When the aspect ratio exceeds 20, the shape of the projections becomes too sharp, and the projections are detached by the roller-to-roll conveyance, and the appearance of the scratches of the laminate or the like is poor, or the wiring is short-circuited. After that. When the aspect ratio is less than 3, the projections are easily detached from the resin layer, and even according to the present invention, it is extremely difficult to obtain high adhesion strength. In addition, when the degree of roughening treatment of the gold-11·201223750 foil used in the present invention is represented by Rz (ten-point average roughness), the surface roughness Rz of the surface of the metal foil subjected to the roughening treatment is It is preferably 0.3 μm or more and less than 2.5 μm, and more preferably 0.5 μm or less and less than 2.0 μm. The metal foil can be suitably selected from commercially available products satisfying the above requirements, and is exemplified by JX Nippon Mining & Metals Co., Ltd., trade name AMFN. When the liquid crystal polymer layer is formed of a liquid crystal polymer film, it is preferred that the liquid crystal polymer film and the metal foil are both in the form of a roll from the viewpoint of productivity of the metal-clad laminate. As described below, these rolls are continuously conveyed by the roll-to-roller, and the pressure-bonding is performed by this process. Therefore, the metal-clad laminate can be obtained by a process having good productivity. A suitable method for producing a metal-clad laminate is to laminate a liquid crystal polymer film and a metal foil by thermocompression bonding. From the viewpoint of the uniformity of the joined state, in the thermocompression bonding, a metal press roll having one pair of rubber-free covers can be used as the press roll. Although it is also possible to use a rubber-coated metal roll which is covered with a rubber, at this time, it is difficult to apply pressure roller pressure at 250 ° C or more due to problems such as heat resistance of the adhesive which covers the rubber and the metal roll. Therefore, when a rubber-coated metal press roll is used, only a liquid crystal polymer having a low melting point is applied, and as a result, the obtained metal-clad laminate has low heat resistance and does not have solder heat resistance. The surface of the metal press roll must be warmed by some means. The means is not particularly limited. The heating by the dielectric heating method or the heat medium circulation method can be exemplified. Further, a method in which the pressure roller is placed in the constant temperature cover or a hot air is blown on the surface of the roll may be used, and the above-mentioned -12-201223750 method may be employed. By the above means, the surface temperature of the press roll can be set to be within 8 ° C with respect to the width direction of the roll, whereby the peeling strength of the metal and the liquid crystal polymer layer can be excellent, and the metallized layer having less variation can be obtained. Plywood. Further, by using the above-described metal-free pressure-coated roll without rubber coating, the surface of the roll can be easily heated. The surface temperature of the metal pressure roller may be lower than the heat distortion temperature of the liquid crystal polymer film in the range of 5 to 100 ° C, and more preferably lower than the heat distortion temperature of the liquid crystal polymer film. Temperature of 90 °C. When the surface temperature of the metal press roll is lower than the heat distortion temperature of the liquid crystal polymer film by more than 1 〇〇 ° C, there is a case where the film and the metal foil are insufficient. Further, when the surface temperature of the metal press roll is lower than the heat distortion temperature of the liquid crystal polymer film by less than 5 °C, the flow of the film at the time of pressure bonding becomes conspicuous, and the laminate becomes a poor appearance. In addition, the heat distortion temperature of the liquid crystal polymer film refers to a film which is thermocompression bonded by a thermomechanical analysis device, having a width of 2 mm and a length of 30 mm, a distance between the jigs of 15 mm, and a load of 5 g and a temperature increase rate of 5 ° C. The amount of thermal expansion in the longitudinal direction of the test piece was measured under the condition of /min, and its inflection point was displayed. Further, the pressure at the time of pressure bonding is not particularly limited as long as it can uniformly pressurize the width direction, but it is preferably 5 to 200 kN/m, more preferably 70 to 150 kN/m. In the laminate of the present invention, in the case of the liquid crystal polymer layer and the metal foil, the 180° interlayer peel strength of the metal foil and the liquid crystal polymer layer is 0.5 to 5 kN/m or more at the normal temperature. Good, better for 〇.8 〜2·OkN/m.
本發明之貼金屬層合板，係因金屬箔表面之突起物的 +S - . _ -13- 201223750 縱橫比較大’並且’使用突起物之高度比較低的金屬箔， 故可確保與液晶聚合物層有充分的接著力，且具有於精細 節距加工性或高頻領域中訊號傳送損失小等之優點。本發 明之貼金屬層合板，係特別適合作爲高頻電路基板或高密 度配線基板所使用的材料。另外，於本發明中，亦可使液 晶聚合物層的兩面具有金屬箔。例如，藉由在〗片液晶聚 合物薄膜的兩面’分別重疊有1片金屬箔的狀態下進行熱 壓接’可製造具有金屬箔/液晶聚合物薄膜/金屬箔之3層構 造的層合板。 【實施方式】 〔實施例〕 接著，雖藉由實施例來具體說明本發明，但本發明並 不因此等實施例而受到任何限定。另外，針對後述之本發 明的實施例，只要沒有特別的理由，則加工條件、測量（ 評估）條件係如下所述。 〔突起物的形狀與尺寸的測量〕 以剖面硏磨機，將形成有因粗化處理所成之突起物的 金屬箔剖面加工，並進行剖面SEM觀察，且利用觀察影像 來計測出突起物的高度Η與突起物之根部的寬度L之尺寸。 該突起物的高度Η與根部的寬度L，係由觀察影像任意地選 擇5點以上，並記錄其平均値。 -14- 201223750 〔表面粗糙度之測量〕 以JIS B 0601爲標準，使用觸針式表面粗度測定器（ TENCOR公司製、TENCOR P-10)，在測量寬度 200μπ^ 條件下測量出Rz。 〔層間剝離強度〕 以JISC 6471 8·1方法B( 180°方向剝離）爲標準，將 寬度1 mm之金屬箔剝離並測量。層間剝離強度，係對從貼 金屬層板所任意採取的3個以上之試驗片進行測量，並記 錄其平均値。 〔薄膜厚度公差之測量〕 使用度盤式指示器（dial gauge)，來測量以市售之 蝕刻液將金屬箔從貼金屬層合板去除後之液晶聚合物薄膜 的厚度。測量點的數量，係由任意的點中測量3 0點以上， 將標準偏差乘以3倍後的値（3σ )相對於測量數據之平均 値（Ave_ )之比（3<j/Ave.)，以100分率所表示者爲公差 〔傳送損失之測量〕 於液晶聚合物薄膜的兩面設有金屬箔之兩面貼金屬層 合板中，在兩方的金屬箔實施電路加工，而製作出由一方 爲接地，另一方爲訊號線的導體2層所構成之傳送線路（ 微帶傳輸線）。調整電路之導體寬度與導體厚度，以使該 -15- 201223750 傳送線路的特性阻抗成爲50Ω。傳送線路的設計，係使用 高頻電路設計用之軟體（Agilent Technologies公司製， Advanced Design System)來進行。於傳送線路的兩末端 ，係配置有由測量用訊號線•接地2條所成之等間隔的襯 墊。傳送損失，係藉由使用微波用Pi coprobe ( GGB公司製 )與網路分析器（Agilent Technologies公司製，E8364B) ，來測量S參數而計算出。" (實施例1〜3 ) 對厚度50 μιη、膜厚公差5.0%之液晶聚合物薄膜（ JAPAN GORE ΤΕΧ股份有限公司製，商品名BIAC，熱變形 溫度300°C )的兩面，分別重疊厚度12μιη的電解銅箔1，並 在無橡膠覆蓋的金屬加壓軋輥之間進行連續熱壓接，而製 造出實施例1之貼金屬層合板。此外，使用厚度12μιη的電 解銅箔2及3，與上述相同地對液晶聚合物薄膜的兩面進行 連續熱壓接，而製造出實施例2及實施例3之貼金屬層合板 〇 詳細而言，上述液晶聚合物薄膜與上述電解銅箔，係 皆使用長尺的滾筒狀者，並使用層合時設置於恆溫蓬蓋內 且表面溫度設定成24(TC (在寬度方向的溫度差爲8 °C以內 )的金屬加壓軋輥（直徑3 5 0mm )，以4m/分鐘、壓力 12 0kN/m的條件下進行連續熱壓接。另外，金屬加壓軋輥 ，係適用可調整成下述者，即：藉由埋設在軋輥的內部之 複數發熱線圈，而使加熱加壓時不易產生軋輥寬度方向之 -16- 201223750 金屬加壓軋輥表面的外周差。 上述實施例所使用的電解銅箔，係皆將接觸到液晶聚 合物薄膜的面粗化處理，如第1圖所示，形成在表層部的 突起物之高度Η，以及，突起物高度Η相對於突起物之根 部的寬度L之比（H/L，縱橫比），係分別如表1所示。此 外，經粗化處理的面之表面粗糙度Rz係如表1所示。針對 所得之貼金屬層合板的評估結果，一倂於表1中顯示。 (比較例1〜4 ) 厚度12μιη的電解銅箔，其因粗化處理所形成之突起物 具有如表1所示之縱橫比（H/L )與高度Η，且，除了使用 具有表面粗糙度Rz之電解銅箔以外，係與實施例丨相同地 製造貼金屬層合板，並進行評估。 -17- 201223750 【1® 傳送損失 [d B/mm] 4 0GHz CO ο ο (Ο ο ο (Ο ο ο Ν Τ Ο 因電路剝離而不可測量 因電路剝離而不可測量 因電路剝離而不可測量 3 0GHz in ο ο I ιο ο ο 1 to ο ο 1 σ) ο ο 1 2 0GHz 寸 ο ο I 寸 ο ο 1 寸 ο ο 1 to ο ο 1 1 OGH ζ C0 ο ο I C0 ο ο 1 C0 ο ο 1 寸 ο ο 1 ii 瘁槲 踩it s 燦·Ν ο ιο ο ΙΟ ο ΙΟ ο ιη Τ— in 〇 ΙΟ 〇 ω 層間剝 離強度 [k N/m] r- ο Γ^ ο 寸 〇 C0 d 寸 〇 表面粗糙度 R ζ [μ m] 00 r- 00 广 (Ο CO N CVJ CNJ 〇 CVJ 突起物 之高度 Η ίβ m] 00 ο CO ο 00 ο (Ο 04 in op τ~ 〇 OJ 突起物之 縱橫比 (H/L) ο 00 ο 寸 ο ο r— CO C0 CO in 實施例1 實施例2 實施例3 比較例1 比較例2 比較例3 比較例4 -18- 201223750 〔產業上之可利用性〕 本發明之貼金屬層合板，係以特性阻抗匹配性優異， 傳送損失低爲優點的電路基板材料，且特別適合作爲高頻 電路基板所使用之材料。此外，相對於以往仍存在課題之 低介電材料，可提供密著強度（層間密著強度）高，且信 賴性高的基板，並可利用在各種電子電路產業中。 【圖式簡單說明】 [第1圖]第1圖係對本發明所使用之經粗化處理的金屬 箔表層部之突起物做剖面觀察的槪略圖。 -19·The metal-clad laminate of the present invention is made of a liquid metal polymer because the protrusion of the surface of the metal foil is +S - . _ -13- 201223750 which is relatively large in length and width and uses a metal foil having a relatively low height of the protrusions. The layer has sufficient adhesion and has the advantages of small signal transmission loss in the fine pitch processing or high frequency field. The metal-clad laminate of the present invention is particularly suitable as a material for use in a high-frequency circuit substrate or a high-density wiring substrate. Further, in the present invention, the liquid crystal polymer layer may have a metal foil on both sides thereof. For example, a laminate having a three-layer structure of a metal foil/liquid crystal polymer film/metal foil can be produced by performing thermocompression bonding in a state in which one metal foil is superposed on both sides of a liquid crystal polymer film. [Embodiment] [Embodiment] The present invention will be specifically described by way of examples, but the present invention is not limited to the examples. Further, in the examples of the present invention to be described later, the processing conditions and the measurement (evaluation) conditions are as follows unless otherwise specified. [Measurement of Shape and Size of Protrusion] A cross-section honing machine is used to form a cross section of a metal foil formed with a projection formed by roughening, and to perform cross-sectional SEM observation, and to measure projections by observation images. The height is the size of the width L of the root of the protrusion. The height Η of the protrusion and the width L of the root were arbitrarily selected from the observation image by 5 or more points, and the average enthalpy was recorded. -14- 201223750 [Measurement of surface roughness] Rz was measured under the measurement width of 200 μπ^ using a stylus type surface roughness measuring instrument (TENCOR P-10, manufactured by TENCOR Co., Ltd.) in accordance with JIS B 0601. [Interlayer peel strength] A metal foil having a width of 1 mm was peeled off and measured in accordance with JIS C 6471 8·1 Method B (180° direction peeling). The interlaminar peel strength was measured for three or more test pieces arbitrarily taken from the metal clad laminate, and the average enthalpy was recorded. [Measurement of Film Thickness Tolerance] A dial gauge was used to measure the thickness of the liquid crystal polymer film obtained by removing the metal foil from the metal-clad laminate with a commercially available etching solution. The number of measurement points is the ratio of 値(3σ) after multiplying the standard deviation by 3 times to the average 値(Ave_) of the measured data by any point above 3 points (3<j/Ave.) In the case of the 100-point rate, the tolerance is measured. [Measurement of the transmission loss] In the metal-clad laminate with the metal foil on both sides of the liquid crystal polymer film, the metal foil is processed on both sides to produce one side. The ground is connected to the ground, and the other is a transmission line (microstrip transmission line) composed of two layers of conductors of the signal line. Adjust the conductor width of the circuit and the thickness of the conductor so that the characteristic impedance of the -15-201223750 transmission line becomes 50Ω. The design of the transmission line was carried out using a software for high-frequency circuit design (Advanced Design System, manufactured by Agilent Technologies). At both ends of the transmission line, there are linings which are equally spaced by the measurement signal line and the grounding. The transmission loss was calculated by measuring the S parameter using a microwave using Pi coprobe (manufactured by GGB Co., Ltd.) and a network analyzer (manufactured by Agilent Technologies, E8364B). < (Examples 1 to 3) The thickness of each of the two sides of a liquid crystal polymer film (manufactured by JAPAN GORE Co., Ltd., trade name: BIAC, heat distortion temperature: 300 ° C) having a thickness of 50 μm and a film thickness tolerance of 5.0% was overlapped. A metallized laminate of Example 1 was produced by subjecting an electrolytic copper foil 1 of 12 μm to continuous thermocompression bonding between metal-free press rolls without rubber coating. Further, in the same manner as described above, the electrolytic copper foils 2 and 3 having a thickness of 12 μm were subjected to continuous thermocompression bonding on both surfaces of the liquid crystal polymer film to produce the metallized laminates of Examples 2 and 3, in detail. The liquid crystal polymer film and the above-mentioned electrolytic copper foil are both long-sized roller-shaped ones, and are placed in a thermostatic cover when laminating, and the surface temperature is set to 24 (TC (temperature difference in the width direction is 8 °) The metal press roll (with a diameter of 305 mm) of C is continuously thermocompression bonded under the conditions of 4 m/min and a pressure of 120 kN/m. In addition, the metal press roll can be adjusted to be as follows. That is, the outer peripheral surface of the surface of the metal press roll of the -16-201223750 is less likely to occur in the width direction of the roll by the plurality of heat-generating coils embedded in the inside of the roll. The electrolytic copper foil used in the above embodiment is The surface roughening treatment of the liquid crystal polymer film is contacted, as shown in Fig. 1, the height Η of the protrusion formed in the surface layer portion, and the ratio of the height Η of the protrusion to the width L of the root portion of the protrusion ( H/L, The transverse ratios are shown in Table 1. In addition, the surface roughness Rz of the roughened surface is shown in Table 1. The evaluation results of the obtained metallized laminates are shown in Table 1. (Comparative Examples 1 to 4) Electrodeposited copper foil having a thickness of 12 μm, the projections formed by the roughening treatment have an aspect ratio (H/L) and a height Η as shown in Table 1, and have surface roughness in addition to use. A metal-clad laminate was produced and evaluated in the same manner as in Example 175 except for the electrolytic copper foil of Rz. -17- 201223750 [1® Transmission loss [d B/mm] 4 0GHz CO ο ο (Ο ο ο ( ο ο ο Ν Τ 而不 而不 Ο 电路 电路 电路 Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο Ο 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因 因ο ο 1 inch ο ο 1 to ο ο 1 1 OGH ζ C0 ο ο I C0 ο ο 1 C0 ο ο 1 inch ο ο 1 ii 瘁槲 step it s Ν Ν ο ο ιο ο ΙΟ ο ΙΟ ο ι Τ Τ — in 〇ΙΟ 〇 ω interlayer peel strength [k N/m] r- ο Γ ^ ο inch 〇 C0 d inch 〇 surface roughness R ζ [μ m] 00 r- 00 广(Ο CO N CVJ CNJ 〇CVJ Height of the protrusion Η ίβ m] 00 ο CO ο 00 ο (Ο 04 in op τ~ 〇OJ Aspect ratio of the protrusion (H/L) ο 00 ο inchο ο r —CO C0 CO in Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 -18- 201223750 [Industrial Applicability] The metal-clad laminate of the present invention is characterized by characteristic impedance A circuit board material having excellent matching properties and low transmission loss, and is particularly suitable as a material used for a high-frequency circuit substrate. Further, it is possible to provide a substrate having high adhesion strength (interlayer adhesion strength) and high reliability with respect to a low dielectric material which has a problem in the past, and can be used in various electronic circuit industries. BRIEF DESCRIPTION OF THE DRAWINGS [Fig. 1] Fig. 1 is a schematic cross-sectional view showing a projection of a surface of a roughened metal foil surface layer used in the present invention. -19·