1328982 九、發明說明： 【發明所屬之技術領域] 本發明係關於一種軟性金屬覆膜積層板（f丨exible metal clad laminate)，更明確地說，係關於一種其表面形 狀有利於形成精細圖案的軟性金屬覆膜積層板。 【先前技術】 近年來，使用捲帶晶粒自動接合技術（tape Automated Bonding，TAB)或軟式印刷電路板（FlexibIe Print Circuit， FPC)的印刷電路板多應用於作為尺寸及重量較小之電子 產品的印刷電路板。迄今’此類型印刷電路板的設計仍是 用一種黏著劑，例如環氧樹脂黏著劑，將一層金屬薄膜黏 附在一層軟性塑膠基材上° 不過，為了容納更多的電子裝置’此類型的印刷電路 板越顯輕薄。同時’由於塑膠基材與金屬薄摸之間的黏著 力並不佳，目前已著手發展不須使用黏著創而形成金屬層 的技術。例如，眾所皆知地’金屬薄膜係以薄膜形成技術’ 例如真空沉積、濺鍍及離子電鐘’直接在塑膠基材上形成’ 立後再藉由電解電鍵之類的技術在金属薄族上堆積成金屬 電鍍層。 若軟性金屬覆膜積層板使用上述方法形成’便可在該 軟性金屬覆膜積層板之上表面形成配線圖案而製成多種產 品。此時，需要精準的钱刻技術以形成精準的圖案’而此 #刻性質則與軟性金屬覆膜積層板表面的糖度有極大的關 5 1328982 聯性。 然而，若是只控制其表面的糙度，則能形成的精細圖 案之準確度便相當有限，因為當在不平坦形狀的表面形成 精細圖案時，即便表面的糙度相等，也仍可能會有蝕刻性 質之類的差異。 【發明内容】 本發明之設計係在解決先前技藝的問題，因此本發明 之目的係提供一種適於準確的形成精細圖案的軟性金屬覆 膜積層板，其係藉由在形成精細圖案時對具有不平坦形狀 和链度的表面施用光反射量而達成。 為了實現上述目的，本發明提供一種適於形成精細圖 案的軟性金屬覆膜積層板，其包含一導電金屬層，其表面 糙度（Rz)為0.5微米或更小，假設當光以第一入射角入射 在表面時之光反射量為I且當光以一大於第一入射角之第 二入射角入射在表面時之光反射量為II，則Π/Ι為1 .0或 以上，使其在形成精細圖案時得以提供最適化的蝕刻性質。 【實施方式】 在本文中，本發明的較佳實施例將參照附圖詳加說 明。在進行說明之前，應了解本專利說明書和附屬的申請 專利範圍中所使用的術語並不侷限於一般用語和字典上認 定的意義，而是由發明者根據其原理提出最佳解釋所定出 術語而根據與本發明的技術觀點相當的意義和觀點來解 6 1328982 釋。因此，本文中揭示的說明係為了例示較佳實施例 非藉以限制本發明的領域，因而其它的類似情況及修 仍涵蓋在本發明之精神和領域中。 第1圖的斷面圖係簡要的呈現本發明之適用於精 案的軟性金屬覆膜積層板的較佳實施例。 參考第1圖，依據本實施例，適用於精細圖案的 金屬覆膜積層板包括一聚合膜10; —種金屬層20，其 )一種導導金屬形成且位在該聚合膜10上；及一導電金 30，其係位在該種金屬層20上。 聚合膜10較佳者具有作為軟性金屬覆膜積層板 的彈性，例如由聚醯亞胺薄膜製成。該聚醯亞胺薄膜 良好的熱阻性和彈性及優異的機械強度，同時其熱擴 數與銅相當，因而常應用作為此種聚合膜1〇的材質。 種金屬層 20 係藉由空膜沉積法（vaccum deposition method)，例如藏鍍和離子電鐘，在該聚合 表面上形成。這些方法適於增強其黏著力。 種金屬層20係由銅或其合金製成，亦可使用鎳、 鎳鉻合金。不過，本發明對種金屬層的材質並未限制 可採用其它的材質。 導電金屬層 30 是藉由電解電鍍或無電鍍 (electroless plating)在種金屬層20上形成。其中以電 鍍較佳，因為其可快速又經濟的形成薄膜並使表面有 的平順性。使用電解電鍍時，其係將種金屬層20形成 所在的聚合膜1 0浸潰在一濕電鍍溶液中，將電源的陰 ，而 飾均 細圖 軟性 係由 屬層 所需 具有 張係 fi I m 膜10 鉻或 ，亦 金法 解電 良好 位置 極連 7 1328982 接到該種金屬層20，然後將電能接通到浸入該濕電鍍溶液 中的陽極以便將濕導電金屬層抽取到種金屬層20上。使用 無電鍍金時，先藉由鈀鹽溶液或之類將抽取用顆粒附著在 種金屬層20上，再將該聚合膜10浸入一無電鍍金溶液中。 導電金屬層30，若考量電傳導性，以銅質或其合金較 佳，不過本發明對導電金屬層30之材質並無設限，亦可使 用他種材質。 此外，導電金屬層30之表面糙度較佳是0.5微米或以 下。 在形成一精細圖案時，考量軟性金屬覆膜積層板的效 能，其表面糙度是影響蝕刻性的一項相當重大的因素。因 此，所形成的導電金屬層之糙度Rz較佳為0.5微米或更 小，以便形成小於5 0微米的精細圖案。 本發明中，在進行濕電鍍以形成軟性金屬覆膜積層板 的導電金屬層30時，該軟性金屬覆膜積層板的表面形狀是 藉由添加在該電解質中的添加物予以控制。例如，欲改變 該軟性金屬覆膜積層板之不均勻形狀，可使用添加物例 如：分子量小的水性纖維素醚、分子量小的水性聚伸烷二 醇醚、分子量小的水性聚伸乙亞胺、及水性磺化有機硫化 物。 第2a至2c圖的斷面圖顯示根據上述方法形成的軟性 金屬覆膜積層板的表面之多個實施例。 雖然糙度相等，但是當精細圖案係在一表面不平坦的 軟性金屬覆膜積層板上形成時，其光罩的黏著性質就可能 8 1328982 不同，且其表面之光反射量也會不同。 參照第2a至2c圖，第2a圖的不平坦面較大而第2c 圖的不平坦較平缓。在形成精細圖案時，第2c圖之光罩的 黏著性質將優於第2a圖。 此外，關於表面的光反射量，在70度的大入射角 B 和5度的小入射角A兩種情形下，其光反射量是由第2a 圖到第2 c圖依次增加。 參考第2a圖，當不平坦的形狀相同時，就70度之較 大入射角B而言，由於不平坦的高度大於光的傾角造成光 攔截，因此在70度之大入射角B的光反射量反而較5度 的小入射角A減少。 不過，參考第2c圖，當不平坦的形狀相同時’ 70度 的大入射角B有額外的散射光加入其實際的光反射量，因 而使其光反射量反而較5度的小入射角A增加。 若使用上述方法來測量在軟性金屬覆膜積層板表面之 光反射量，就可以了解在該表面上形成之不平坦形狀。 以下將說明各種不平坦的形狀對於形成精細圖案造成 的影響效應。 第3a至3c圖之斷面圖係簡要的顯示依據軟性金屬覆 膜積層板表面的不平坦形狀所形成的精細圖案的多種蝕刻 性質。 參考第3a至3c圖，其各有一軟性金屬覆膜積層板 101、102、103，其中包括在聚合膜上形成一種金屬層和一 導電金屬層；一光阻層 200，其係在該軟性金屬覆膜積層 9 1328982 板101、102、103上形成的罩層；及一光罩300，其上可 形成所需要的精細圖案。 當一蝕刻罩201、202、203經由曝光和顯影程序對該 光阻層200製備時，第3a圖的蝕刻罩201會因為嚴重的光 散射而受損。在隨後的製程中進行蝕刻時其將損及所需要 的精細圖案，呈現出來的極可能產生無蝕刻區或過度蝕刻 區，因而便形成拙劣的圖案而非精確的圖案。因此，以類 '；) 似於第3c圖的不平坦形狀蝕刻比第3a圖能更精確的形成 所需要的精細圖案。 以下將藉由具有不同不平坦形狀之本發明的軟性金屬 覆膜積層板之多個實施例詳細說明適用於形成精細圖案的 表面特性。 意即，如第1圖所顯示，軟性銅箔覆膜積層板係由一 銅種子層20和一銅電導層30依序在聚醯亞胺薄膜10上形 成而製成，並測量在入射角5度和70度之光反射量。其中， 在多個實施例和其多個對照實施例中每個的表面糙度 Rz 均為0.5微米或以下。 表 1顯示根據不平坦形狀變化對光反射量的測量結 果。在此，所謂”反射量”是依據世界通用標準方法 ASTM(American Society of Testing Materials)測量亮度與 明度的標準方法，即根據ASTM D245 7和D523，取得的實 驗數據值。 表1 10 1328982 反射量⑴ 反射量(II) 實際圖案照片 II/I 入射角5度 入射角70度 實施例1 110.0 175.9 第4a圖 1.6 實施例2 117.5 133.1 第4a圖 1.1 對照實施例1 46.8 14.4 第4b圖 0.308 對照實施例2 70.7 1.7 第4c圖 0.024 對照實施例3 61.7 1.9 第4c圖 0.030 見表1， 首先，應了解在實施例1 和2中入射角 70度 之光反射量大於入射角5度，因此較接近於第2c圖中顯示 之不平坦形狀，而在對照實施例1至3中入射角7 0度之光 反射量則小於入射角5度，因此較接近於第2a圖之不平坦 的形狀。 為了佐證上述說明，第4a圖之真實照片顯示在具有實 施例1和2之不平坦形狀的軟性金屬覆膜積層板上形成的 精細圖案，其中形成的斷面相當規則而無光阻劑殘留。另 一方面，第4b至4c圖之真實照片則顯示在具有對照實施 例1至3之不平坦形狀的軟性金屬覆膜積層板上形成的精 細圖案，其中由於產生無蝕刻區而使得所形成的斷面呈現 不規則狀。 此外，入射角70度之光反射量較佳是10或以上。此 係因為入射角70度對於軟性金屬覆膜積層板之糙度很敏 感，若光反射量少於10，較可能會產生無蝕刻區及電路筆 直。此外，在上述多個實施例和對照實施例之結果中顯示， 大入射角的光反射量以高於小入射角較佳，即大入射角的 11 1328982 光反射量對小入射角的光反射量之比值是 1.0或以上較 佳，以便能形成所需要的精細圖案而不產生任何無蝕刻區。 本發明在文中已詳細說明。不過，在此要強調的是， 這些詳細說明和多個特定實施例雖稱為本發明的較佳實施 例，卻僅用於例示說明，因為一般精於本技藝之人士均了 解這些詳細說明可在本發明之精髓和範圍中進行各種變動 和調整。 在工業界之適用性 根據本發明，在製造適用於精細圖案的軟性金屬覆膜 積層板時，藉由製備一種表面糙度Rz在0.5微米或更小的 導電金屬層且其中大入射角的光反射量以高於小入射角較 佳，亦即較佳者大入射角的光反射量對小入射角的光反射 量之比值是1.0或以上，才能在形成精細圖案過程中改良 其蝕刻性質。 此外，可利用光反射量在不平坦形狀的表面上的變化 來檢驗軟性金屬覆膜積層板的品質。 【圖式簡單說明】 本發明的其他目的和觀點將參考各附圖在下列實施例 中詳細說明： 第1圖之斷面圖是顯示本發明軟性金屬覆膜積層板的 較佳實施例； 第2a至2c圖之斷面圖是顯示在該軟性金屬覆膜積層 12 1328982 板上層部份形成的不平坦表面的多個實施例； 第3a至3c圖之斷面簡圖是顯示在該軟性金屬覆膜積 層板上層部份形成的不平坦表面形成精細圖案時的蝕刻性 質；及 第4a至4c圖的照片是顯示在該軟性金屬覆膜積層板 上層部份形成的不平坦表面形成之精細圖案。 【主要元件符號說明】 10聚合膜 3 0導電金屬層 102軟性金屬覆膜積層板 2 0 0光阻層 300光罩 2 03蝕刻層 B入射光 2 0種金屬層 101軟性金屬覆膜積層板 103軟性金屬覆膜積層板 2 0 1蝕刻層 2 0 2钱刻層 A入射光 131328982 IX. Description of the Invention: [Technical Field] The present invention relates to a flexible metal clad laminate, and more particularly to a surface shape which is advantageous for forming a fine pattern. Flexible metal coated laminate. [Prior Art] In recent years, printed circuit boards using Tape Automated Bonding (TAB) or FlexibIe Print Circuit (FPC) have been widely used as electronic products of smaller size and weight. Printed circuit board. So far, this type of printed circuit board is still designed with an adhesive, such as an epoxy adhesive, to adhere a layer of metal film to a layer of soft plastic substrate. However, in order to accommodate more electronic devices, this type of printing The board is lighter and thinner. At the same time, due to the poor adhesion between the plastic substrate and the thin metal, the technology for forming a metal layer without using adhesive bonding has been developed. For example, it is well known that 'metal film is formed by thin film forming technology' such as vacuum deposition, sputtering and ion-electric clocks directly on plastic substrates, and then by techniques such as electrolytic bonding. Stacked into a metal plating layer. If a soft metal-clad laminate is formed by the above method, a wiring pattern can be formed on the upper surface of the flexible metal-clad laminate to produce a variety of products. At this time, precise money engraving techniques are required to form a precise pattern, and the nature of the engraving is greatly related to the sugar content of the surface of the soft metal-clad laminate. However, if only the roughness of the surface is controlled, the accuracy of the fine pattern that can be formed is rather limited, because when a fine pattern is formed on the surface of the uneven shape, even if the roughness of the surface is equal, etching may still occur. Differences such as nature. SUMMARY OF THE INVENTION The design of the present invention solves the problems of the prior art, and it is therefore an object of the present invention to provide a soft metal-clad laminate suitable for accurately forming a fine pattern by having a fine pattern when forming a fine pattern. The surface of the uneven shape and the chain degree is achieved by applying a light reflection amount. In order to achieve the above object, the present invention provides a soft metal coated laminate suitable for forming a fine pattern comprising a conductive metal layer having a surface roughness (Rz) of 0.5 μm or less, assuming that light is incident at a first incidence When the angle is incident on the surface, the amount of light reflection is I and when the light is incident on the surface at a second incident angle greater than the first incident angle, the amount of light reflection is II, then Π/Ι is 1.0 or more, so that Optimal etch properties are provided when forming a fine pattern. [Embodiment] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Before the explanation, it should be understood that the terms used in the scope of this patent specification and the accompanying patent application are not limited to the general term and the meaning of the dictionary, but the term is determined by the inventor according to the principle of the best explanation. The interpretation of 6 1328982 is based on the meaning and viewpoints comparable to the technical point of view of the present invention. Therefore, the descriptions disclosed herein are intended to be illustrative of the preferred embodiments and are not intended to limit the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing a preferred embodiment of a soft metal coated laminate suitable for use in the present invention. Referring to FIG. 1, in accordance with the present embodiment, a metal coated laminate suitable for a fine pattern includes a polymeric film 10; a metal layer 20 formed with a conductive metal and positioned on the polymeric film 10; Conductive gold 30, which is tied to the metal layer 20. The polymer film 10 preferably has elasticity as a flexible metal film laminate, and is made of, for example, a polyimide film. The polyimide film has good thermal resistance and elasticity and excellent mechanical strength, and its thermal expansion is equivalent to that of copper. Therefore, it is often used as a material for such a polymeric film. The metal layer 20 is formed on the polymerized surface by a vaccum deposition method such as a plating plate and an ion clock. These methods are suitable for enhancing their adhesion. The metal layer 20 is made of copper or an alloy thereof, and nickel or nickel-chromium alloy may also be used. However, the material of the metal layer of the present invention is not limited to other materials. The conductive metal layer 30 is formed on the seed metal layer 20 by electrolytic plating or electroless plating. Among them, electroplating is preferred because it can form a film quickly and economically and has a smooth surface. When electrolytic plating is used, it is obtained by immersing the polymer film 10 in which the seed metal layer 20 is formed in a wet plating solution, and the power source is yin, and the fine-grained soft layer is required to have a tensile system fi I. m film 10 chrome or gold is also decomposed in a good position pole 7 1328982 is connected to the metal layer 20, and then the electrical energy is connected to the anode immersed in the wet plating solution to extract the wet conductive metal layer to the metal layer 20 on. When electroless gold is used, the extracting particles are first attached to the seed metal layer 20 by a palladium salt solution or the like, and the polymer film 10 is immersed in an electroless gold plating solution. The conductive metal layer 30 is preferably copper or an alloy thereof in consideration of electrical conductivity. However, the material of the conductive metal layer 30 is not limited in the present invention, and other materials may be used. Further, the surface roughness of the conductive metal layer 30 is preferably 0.5 μm or less. When forming a fine pattern, the effect of the soft metal coated laminate is considered, and the surface roughness is a considerable factor affecting the etching property. Therefore, the roughness Rz of the formed conductive metal layer is preferably 0.5 μm or less in order to form a fine pattern of less than 50 μm. In the present invention, when wet plating is performed to form the conductive metal layer 30 of the flexible metal-clad laminate, the surface shape of the flexible metal-clad laminate is controlled by the additive added to the electrolyte. For example, in order to change the uneven shape of the soft metal-clad laminate, an additive such as an aqueous cellulose ether having a small molecular weight, an aqueous polyalkylene glycol ether having a small molecular weight, or an aqueous polyethylenimine having a small molecular weight can be used. And aqueous sulfonated organic sulfides. The cross-sectional views of Figs. 2a to 2c show various embodiments of the surface of the flexible metal-clad laminate formed by the above method. Although the roughness is equal, when the fine pattern is formed on a flexible metal-clad laminate which is not flat on the surface, the adhesive property of the mask may be different, and the amount of light reflection on the surface may be different. Referring to Figures 2a to 2c, the uneven surface of Figure 2a is larger and the unevenness of Figure 2c is relatively flat. When the fine pattern is formed, the adhesive property of the mask of Fig. 2c will be superior to that of Fig. 2a. Further, regarding the amount of light reflection of the surface, in the case of a large incident angle B of 70 degrees and a small incident angle A of 5 degrees, the amount of light reflection increases sequentially from the 2ath to the 2ndth. Referring to Fig. 2a, when the uneven shape is the same, in the case of a large incident angle B of 70 degrees, since the uneven height is greater than the inclination angle of the light, the light is intercepted, so the light reflection at the incident angle B at a large angle of 70 degrees The amount is reduced by a smaller incident angle A than 5 degrees. However, referring to Fig. 2c, when the uneven shape is the same, the large incident angle B of 70 degrees has additional scattered light added to its actual light reflection amount, so that the amount of light reflection is smaller than the small incident angle A of 5 degrees. increase. If the above method is used to measure the amount of light reflection on the surface of the flexible metal-clad laminate, the uneven shape formed on the surface can be understood. The effect of various uneven shapes on the formation of fine patterns will be explained below. The cross-sectional views of Figs. 3a to 3c are a brief view showing various etching properties of a fine pattern formed in accordance with the uneven shape of the surface of the flexible metal-clad laminate. Referring to Figures 3a to 3c, each has a flexible metal-clad laminate 101, 102, 103 comprising a metal layer and a conductive metal layer formed on the polymeric film; a photoresist layer 200 attached to the soft metal The cover layer 9 1328982 is formed on the plates 101, 102, 103; and a mask 300 on which the desired fine pattern can be formed. When an etching cap 201, 202, 203 is prepared for the photoresist layer 200 via exposure and development processes, the etching cap 201 of Fig. 3a is damaged by severe light scattering. When etching is performed in a subsequent process, it will damage the desired fine pattern, and it is highly likely that an etch-free region or an over-etched region is formed, thus forming a poor pattern rather than a precise pattern. Therefore, the uneven shape etching like the class '3' can form the desired fine pattern more accurately than the 3a figure. The surface characteristics suitable for forming a fine pattern will be described in detail below by various embodiments of the flexible metal-clad laminate of the present invention having different uneven shapes. That is, as shown in Fig. 1, a soft copper foil-coated laminate is formed by sequentially forming a copper seed layer 20 and a copper electrically conductive layer 30 on the polyimide film 10, and measuring the incident angle. The amount of light reflection at 5 and 70 degrees. Here, the surface roughness Rz of each of the plurality of examples and the plurality of comparative examples thereof was 0.5 μm or less. Table 1 shows the measurement results of the amount of light reflection according to the change in the uneven shape. Here, the "reflection amount" is a standard method for measuring brightness and brightness according to ASTM (American Society of Testing Materials), that is, experimental data values obtained in accordance with ASTM D245 7 and D523. Table 1 10 1328982 Reflectance (1) Reflectance (II) Actual Pattern Photo II/I Incidence Angle 5 Degrees Incident Angle 70 Degrees Example 1 110.0 175.9 Figure 4a Figure 1.6 Example 2 117.5 133.1 Figure 4a Figure 1.1 Comparative Example 1 46.8 14.4 Figure 4b Figure 0.308 Comparative Example 2 70.7 1.7 Figure 4c Figure 0.024 Comparative Example 3 61.7 1.9 Figure 4c Figure 0.030 See Table 1. First, it should be understood that in Examples 1 and 2, the amount of light reflected at an incident angle of 70 degrees is greater than the angle of incidence. 5 degrees, so it is closer to the uneven shape shown in Fig. 2c, and in the comparative examples 1 to 3, the light reflection amount of the incident angle 70 degrees is smaller than the incident angle of 5 degrees, and thus is closer to the 2a map. Uneven shape. In order to support the above description, the real photograph of Fig. 4a shows a fine pattern formed on the flexible metal-clad laminate having the uneven shape of Examples 1 and 2, in which the formed cross section is relatively regular and no photoresist remains. On the other hand, the real photographs of Figs. 4b to 4c show the fine patterns formed on the soft metal-clad laminate sheets having the uneven shapes of Comparative Examples 1 to 3, in which the formed regions are formed due to the generation of the etching-free regions. The section is irregular. Further, the amount of light reflection at an incident angle of 70 degrees is preferably 10 or more. This is because the incident angle of 70 degrees is sensitive to the roughness of the soft metal-clad laminate. If the amount of light reflection is less than 10, it is more likely to produce an etch-free area and a straight circuit. Further, in the results of the above various embodiments and comparative examples, it is shown that the light reflection amount at a large incident angle is preferably higher than a small incident angle, that is, a light reflection amount of 11 1328982 at a large incident angle to a small incident angle. The ratio of the amounts is preferably 1.0 or more so that the desired fine pattern can be formed without producing any etch-free regions. The invention has been described in detail herein. It is to be expressly understood, however, that the claims of the claims Various changes and modifications are made in the spirit and scope of the invention. Applicability in the Industry According to the present invention, in the production of a soft metal-clad laminate suitable for a fine pattern, a light having a surface roughness Rz of 0.5 μm or less and a large incident angle is prepared. The amount of reflection is preferably higher than the small incident angle, that is, the ratio of the amount of light reflected by the larger incident angle to the amount of light reflected by the small incident angle is 1.0 or more, so that the etching property can be improved in the process of forming the fine pattern. Further, the quality of the soft metal-clad laminate can be examined by the change in the amount of light reflection on the surface of the uneven shape. BRIEF DESCRIPTION OF THE DRAWINGS Other objects and aspects of the present invention will be described in detail in the following embodiments with reference to the accompanying drawings. FIG. 1 is a cross-sectional view showing a preferred embodiment of the flexible metal-clad laminate of the present invention; 2A to 2c are cross-sectional views showing various embodiments of the uneven surface formed on the upper portion of the flexible metal-clad laminate 12 1328982; the cross-sectional views of the 3a to 3c are shown in the soft metal The etching property when the uneven surface formed by the layer portion of the laminated layer is formed into a fine pattern; and the photographs of FIGS. 4a to 4c are fine patterns formed by the uneven surface formed on the layer portion of the flexible metal coated laminate. . [Description of main components] 10 polymer film 30 conductive metal layer 102 soft metal coated laminate 2 0 photoresist layer 300 mask 2 03 etching layer B incident light 2 0 metal layer 101 soft metal coated laminate 103 Soft metal coated laminate 2 0 1 etching layer 2 0 2 money layer A incident light 13