201208509 六、發明說明： 【發明所屬之技術領域】 本發明係關於印刷電路板之組裝及更特別係關於於製& 印刷電路板組件時所使用之有機可焊防護劑塗料之處理 【先前技術】 使用印刷電路板（PCB)以藉由使用導電通路或跡線機械 支撐並電連接電子元件，其中該等通路或跡線—般係钱刻 於已層壓於一非導電基板上之銅板上。結果係—印刷線路 板或蝕刻線路板，且一旦組裝上電子元件，則其—般係稱 為印刷電路組件或印刷電路板組件（PCba)。 正如PCB之導電層一般係由已經圖案化以產生用於連接 及互聯該等電子元件之跡線的薄銅箔層所製成。最初，元 件包括安裝並焊接於鑽入該PCB之小孔中之導線以與該導 電銅層接觸。此鑽入過程需要非常精確、非常小的機械 頭、或非常準確的雷射鑽孔技術。最近，此「通孔」構建 方法已逐漸被「表面安裝」（其中將該等元件置於該pcB外 表面上之導電襯塾上，且使用焊料以電及機械方式固定於 該PCB)構建替代。 表面安裝具有數個優於通孔技術之優點，包括將較小的 兀相接至該PCB之能力；允許遠較多數量之元件及每個 兀件通較多之連接’需要鑽的孔較少；簡化、自動化及更 决速’、且裝’雙側組裝能力；較佳機械性能；及較低元件成 本。 在先前技術中’導電襯塾之塗層通常係由錫-錯合金製 150095.doc 201208509 · 成，但是由於R0HS(有害性物質限制）指令對電子裝置中限 制使用錯，在銅導電襯墊上使用無錯塗層已成為標準處理 法。藉由多種焊接技術將元件附接至銅襯墊，已知最常用 的技術係回流焊接。回流焊接包括使用一禪錫膏（即，粉 狀焊料與助熔劑之黏性混合物），其暫時將元件㈣Μ 等襯塾中。隨後，小心加熱(如’藉由紅外燈或在供箱中 之熱空氣對流）該組件以完成該連接之焊接。回流焊接處 理在焊錫膏中溶化焊料合金顆粒，而無過熱或損壞電子元 件且在該等元件與該等導電襯墊之間形成一強持久的冶金 結合，以提供電子電路結構完整性及導電率。標準的回流 焊接處理係四個階段布「问 j, u h區」中進行，各階段或區具有獨 特的溫度曲線，即預熱、熱浸、回流及冷卻。 爲了使焊接處理在該襯墊與元件之間建立有效且堅實的 機械及電連接，需使該銅襯墊無任何表面污染物（包括可 能存在之氧化物）。因為銅容易氧化，所以在該銅襯墊表 面上提供一已知為有機可焊防護劑（〇Sp)塗料之保護層直 至回流焊接處理開始。然而，爲了有效的回流焊接處理， 需要移除該OSP塗料以暴露該銅襯墊。 主要有兩種方法用於在回流焊接之前移除該〇卯層，但 該兩者均有缺點。在第一種方法中，可將特定化學溶劑施 用於該OSP層，再進行焊錫膏印刷。此溶劑係用於溶解該 OSP層並製備銅襯墊表面以進行焊錫膏印刷。此方法之缺 點包括增加與生產相關之時間、材料及能源成本之額外操 作步驟。此外，此方法產生額外的廢水。 150095.doc 201208509 第二種已知用於移除該〇sp層之方法係在焊錫膏混合物 中使用更咼反應性之助炫劑，此助熔劑係於預熱階段時溶 解該OSP層。此方法亦增加製程之成本及廢水，但是具有 與持續裝置小型化相關之更嚴重的問題。特定言之，隨著 電子兀件尺寸繼續減小，導電襯墊之尺寸及該PCB上之元 件之間的㈣亦減，】、。對任何特定襯塾而t，此相應地導 致需使用較少焊錫膏及因此使用較少助熔劑。該較少量之 助溶劑可能無法有效地完全溶解該osp層，而可能造成焊 點之品質及可靠性問題。 因此，相關技術中需改良生產PCB組件且特別係在回流 焊接處理之前自導電襯墊移除posp層之方法。 【發明内容】 本發明係關於PCB之組裝，且關於於製造PCBA時所使 用之0SP塗料之處理。特定言之，本發明提供回流焊接前 移除OSP塗料之改良方法，其克服上述有關先前技術之缺 點。本發明之改良方法包括使用一電漿氛圍處理並移除該 OSP塗料。 【實施方式】 本發明係關於在回流焊接一 PCB之前處理並移除0Sp塗 料之改良。特定言之，本發明使用一種電漿氛圍以在該 PCB進入回流焊接製程之前處理並移除該〇sp塗料。本發 明方法克服先前技術移除0SP之方法相關缺點。特定言 之本發明無為特定溶劑或特定助炫劑材料，因此消除額 外的材料成本及考量。此外，該電漿氛圍可係目前流線型 150095.doc 201208509 操作系統内產生。此外，本發明方法不產生額外的廢水且 可有效用於更小的電子元件尺寸，而不降低該焊料接合之 品質或可靠性。 參考圖1將更詳細地描述本發明，在圓！令一回流焊 統1〇-般係描述為包含-焊錫膏印刷站2〇、一元件取放站 30及-回流站40。亦顯示—具有一在適當位置之⑽層之 PCB 50及-電|源6{)。操作時，—般藉由—輸送帶將具有 該OSP層之PCB 50以圖i所示之箭頭方向朝該回流焊接系 統^動。將該電漿源6G置於該pCB 5G進人該系統ι〇之區 域正前方，且提供一能移除該〇sp層之電漿氛圍。該電漿 源60可係任何已知之電聚產生器，如大氣電浆搶且可由一 系列經排列以確保該電聚氛圍覆蓋該PCB 50之整個寬产之 嗔嘴組成。較佳係、安置該等喷嘴以水平地提供電^該 PCB之表面上，但是其他排列(包括斜置喷嘴)係在本發明 範·#之内。可將該系列之喷嘴併入該輸送帶之頂部。所產 生之電漿可係任何用於移除該⑽之適宜氣體，例如氧 氣、氬氣或其與氮氣之混合物。處理時，在該電漿源的之 出口與該PCB 50之間的距離可係1〇 更小。 藉由使用如上所述之電㈣，可容易地將該⑽層敍刻 掉’並使該等銅襯墊準制於焊錫膏印刷步驟中。正如， 避免先前技術方法之缺點。特定言之，無需使用特定溶劑 或特定回流材料。此外’該電漿源係安裝於生產線上，且 不為整個生產過程增加任何處理時間。 在該製程中之其他階段，亦可有利地使用電聚清除一 J50095.doc 201208509 PCB之導電襯墊。特定言之，可使用電聚或活性氣體在祥 接步驟之刖及期間立即清除該焊料襯墊。 應瞭解本文所述之實施例僅係示例性且熟習此項技術者 在不偏離本發明之精神及範圍下可進行變化及改良。預期 所有此等變化及改良皆包含於如上所述之本發明範圍内。 此外’所揭示之所有實施例在選擇上不是必要的，因為可 合併多項本發明實施例以提供所需結果。 【圖式簡單說明】 圖1係—顯示根據一項本發明實施例之一種處理p C B之 OSP層之方法的示意圖。 【主要元件符號說明】 10 20 30 40 50 60 回流焊接系統 焊錫膏印刷站 元件取放站 回流站 印刷電路板（PCB) 電漿源 150095.doc201208509 VI. Description of the Invention: [Technical Field of the Invention] The present invention relates to the assembly of printed circuit boards and more particularly to the treatment of organic solderable protective agent coatings used in the manufacture and manufacture of printed circuit board assemblies. Using a printed circuit board (PCB) to mechanically support and electrically connect electronic components by using conductive vias or traces, wherein the vias or traces are typically engraved on a copper plate that has been laminated to a non-conductive substrate. . The result is a printed circuit board or an etched circuit board, and once assembled with electronic components, it is commonly referred to as a printed circuit assembly or a printed circuit board assembly (PCba). Just as the conductive layers of the PCB are typically made of a thin layer of copper foil that has been patterned to create traces for connecting and interconnecting the electronic components. Initially, the component includes a wire that is mounted and soldered into a small hole drilled into the PCB to contact the conductive copper layer. This drilling process requires very precise, very small mechanical heads, or very accurate laser drilling techniques. Recently, this "through-hole" construction method has been gradually replaced by "surface mounting" (where the components are placed on the conductive lining on the outer surface of the pcB and solder is electrically and mechanically fixed to the PCB). . Surface mount has several advantages over via technology, including the ability to connect smaller turns to the PCB; allowing a much larger number of components and more connections to each component. Less; simplified, automated and faster speed', and installed 'double-sided assembly capability; better mechanical performance; and lower component costs. In the prior art, the coating of the conductive lining was usually made of tin-alloy alloy 150095.doc 201208509. However, due to the limitation of the ROHHS (Restriction of Harmful Substances) to the electronic device, the copper conductive pad was used. The use of error-free coatings has become the standard treatment. The components are attached to the copper pad by a variety of soldering techniques, the most commonly known technique being reflow soldering. Reflow soldering involves the use of a zen solder paste (i.e., a viscous mixture of powdered solder and flux) that temporarily ties the component (iv) and the like. Subsequently, the assembly is carefully heated (e.g., by convection of the infrared light or hot air in the supply tank) to complete the soldering of the joint. The reflow soldering process dissolves the solder alloy particles in the solder paste without overheating or damaging the electronic components and forming a strong and durable metallurgical bond between the components and the conductive pads to provide structural integrity and conductivity of the electronic circuit. . The standard reflow soldering process is carried out in four stages of “Question j, u h zone”. Each stage or zone has a unique temperature profile, namely preheating, hot dip, reflow and cooling. In order for the soldering process to establish an effective and robust mechanical and electrical connection between the pad and the component, the copper pad is left free of any surface contaminants (including oxides that may be present). Since copper is easily oxidized, a protective layer known as an organic solderable protectant (〇Sp) coating is provided on the surface of the copper liner until the reflow soldering process begins. However, for an effective reflow soldering process, the OSP coating needs to be removed to expose the copper liner. There are two main methods for removing the tantalum layer prior to reflow soldering, but both have disadvantages. In the first method, a specific chemical solvent can be applied to the OSP layer, followed by solder paste printing. This solvent is used to dissolve the OSP layer and prepare a copper liner surface for solder paste printing. The shortcomings of this approach include additional operational steps to increase production-related time, materials, and energy costs. In addition, this method produces additional wastewater. 150095.doc 201208509 A second method known for removing the layer of 〇sp is to use a more reactive fugitive in the solder paste mixture which dissolves the OSP layer during the preheating phase. This method also increases the cost of the process and wastewater, but has more serious problems associated with miniaturization of the continuous unit. In particular, as the size of electronic components continues to decrease, the size of the conductive pads and the (four) between the components on the PCB are also reduced. For any particular lining, this correspondingly results in the need to use less solder paste and therefore less flux. This relatively small amount of co-solvent may not be effective in completely dissolving the osp layer, which may cause problems in solder quality and reliability. Therefore, there is a need in the related art to improve the production of PCB components and in particular to remove the posp layer from the conductive pads prior to the reflow soldering process. SUMMARY OF THE INVENTION The present invention relates to the assembly of PCBs and to the treatment of 0SP coatings used in the manufacture of PCBAs. In particular, the present invention provides an improved method of removing OSP coating prior to reflow soldering that overcomes the above-mentioned disadvantages associated with the prior art. An improved method of the invention includes treating and removing the OSP coating using a plasma atmosphere. [Embodiment] The present invention relates to an improvement in the treatment and removal of an 0Sp coating prior to reflow soldering a PCB. In particular, the present invention uses a plasma atmosphere to treat and remove the 〇sp coating prior to the PCB entering the reflow soldering process. The method of the present invention overcomes the disadvantages associated with prior art methods of removing 0SP. In particular, the invention is not a specific solvent or a particular builder material, thus eliminating additional material costs and considerations. In addition, the plasma atmosphere can be generated within the current streamlined 150095.doc 201208509 operating system. Moreover, the method of the present invention does not produce additional wastewater and can be effectively used for smaller electronic component sizes without reducing the quality or reliability of the solder joint. The invention will be described in more detail with reference to Figure 1, in a circle! A reflow soldering system is described as including a solder paste printing station 2, a component pick-and-place station 30, and a reflow station 40. Also shown is a PCB 50 with a (10) layer in place and a source 6{). In operation, the PCB 50 having the OSP layer is moved toward the reflow soldering system in the direction of the arrow shown in Figure i by a conveyor belt. The plasma source 6G is placed in front of the pCB 5G into the area of the system ι and provides a plasma atmosphere that removes the 〇sp layer. The plasma source 60 can be any known electropolymerizer, such as atmospheric plasma, and can be comprised of a series of nozzles that are arranged to ensure that the electropolymer atmosphere covers the entire width of the PCB 50. Preferably, the nozzles are positioned to provide electrical power to the surface of the PCB, but other arrangements (including oblique nozzles) are within the scope of the present invention. The series of nozzles can be incorporated into the top of the conveyor belt. The plasma produced can be any suitable gas for removing the (10), such as oxygen, argon or a mixture thereof with nitrogen. During processing, the distance between the exit of the plasma source and the PCB 50 can be less than 1 。. The (10) layer can be easily erased by using the electric (four) as described above and the copper pads are made standard in the solder paste printing step. Just as to avoid the shortcomings of the prior art methods. In particular, there is no need to use a specific solvent or a specific reflow material. In addition, the plasma source is installed on the production line and does not add any processing time to the entire production process. At other stages of the process, it is also advantageous to use electropolymerization to remove the conductive pads of a J50095.doc 201208509 PCB. In particular, the solder pad can be removed immediately after and during the agitation step using electropolymer or reactive gas. It is to be understood that the embodiments described herein are merely exemplary and those skilled in the art can be modified and modified without departing from the spirit and scope of the invention. All such changes and modifications are intended to be included within the scope of the invention as described above. Moreover, all of the embodiments disclosed are not essential in the selection, as many embodiments of the invention may be combined to provide the desired results. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing a method of processing an OSP layer of p C B according to an embodiment of the present invention. [Main component symbol description] 10 20 30 40 50 60 Reflow soldering system Solder paste printing station Component pick-and-place station Reflow station Printed circuit board (PCB) Plasma source 150095.doc