201002162 九、發明說明： 【發明所屬之技術領域】 本發明涉及印刷電路板製作領域，特別涉及一種電路 板及其製作方法。 【先前技術】 利用喷墨列印技術製作導電線路於近年來受到了廣泛 關注，此方法只需將所需線路圖形直接由電腦給出，再藉 由控制器控制喷墨印刷系統之喷嘴，將油墨顆粒由喷嘴噴 出並逐點地形成線路圖形，製作線路圖形能夠精確控制線 路之位置及寬度，該方法屬非接觸式數碼圖案製程，可減 少不同印刷材料間相互污染。相較於傳統之線路製作方 法，具有製作流程更加簡化、低成本及低污染之優點。請 參見文獻：Murata，K·; Matsumoto, J.; Tezuka，A.; Oyama，K.; Matsuba, Υ·; Yokoyama, H.; Super fine wiring by inkjet printing Microprocesses and Nanotechnology Conference, ί 2004. Digest of Papers. 2004 International Oct. 27-29, 2004 Page(s):24 - 25。 先前技術中報導了 一種採用喷墨列印含有可溶性鈀鹽 與弱還原劑之墨水製造導電線路之方法。該方法將可溶性 鈀離子與弱還原劑製成可喷墨列印之墨水於基材表面列印 出含有鈀離子線路圖形，然後於該線路圖形經過高能光照 射還原，得到鈀質線路，但由於線路圖形於基材表面之附 著力不佳，線路圖形中沒有被還原之鈀離子與還原後之鈀 6 201002162 -粒子脫落到後續製程之化學溶液中，損壞化學溶液，而且 -線路中含有未反應之還原劑，殘留於導電線路内，對導電 線路之品質具有很大之影響。 因此，有必要提供一種電路板之製作方法，以提升導 電線路於基材表面之附著力，提高導電線路之品質。 【發明内容】 以下將以實施例說明一種電路板及其製作方法。 一種電路板之製作方法包括：對絕緣基材表面進行親 水性處理；將含有可溶性把鹽之油墨印刷於親水處理過之 絕緣基材之表面，形成線路圖形；採用非離子還原劑還原 線路圖形中之纪鹽以形成把質預製線路；於預製線路之表 面鍍覆金屬形成導電線路。 .-種電路板’其包括：絕緣基材，其具有—親水性表 面’她制預製線路形成於該親水性表面上 I覆該預製線路。 电狨心 *相較於先前技術，該電路板之製作方法可增強線路與 、邑緣基材表面之結合能力。後續之把離子還原處理中，採 用非料性還原劑，即有機還原劑與具有還原性之氣體， 。了採用離子型還原劑（如删氣化納、棒樣酸納等）還 二^線路中之把離子之脫吸附與再吸附而引起之線路解 析度下降之問題。 【實施方式】 7 201002162 下面將結合附圖及實施例對本技術方案實施例提供之 電路板及其製作方法作進一步詳細說明。 請參閱圖1，本實施例提供之電路板之製作方法包括以 下步驟： 第一步，對絕緣基材100表面100進行親水性處理。 如圖2所示，本實施例中，絕緣基材100可為製作單 層板時之絕緣層，也可為多層電路板製作過程中之多層電 路板表面壓合之絕緣層。絕緣基材100之材料通常以聚醯 亞胺類材料為主。本實施例中，絕緣基材100為需要製作 單面線路之絕緣層。該絕緣基材100具有用於形成導電線 路之表面110。該絕緣基材100之材質為聚醯亞胺。 藉由對絕緣基材100之表面110進行親水性處理，以 便於後續線路製作時增加表面110結合油墨之能力。增加 表面110之親水性有多種方法，如對絕緣基材100聚合物 進行改性處理，使得表面110形成極性官能團。 本實施例中，採用鹼性溶液對絕緣基材100之表面110 進行親水性處理。對絕緣基材100表面之處理包括以下步 驟：首先，清洗絕緣基材100之表面110。清洗時可採用丙 酮、乙醇或水等溶劑，以除去附著於表面110之汙物、氧 化物、油脂等。然後，應用強鹼性溶液對絕緣基材100之 表面110進行處理。該強鹼性溶液可為KOH溶液或KOH 與KMn04之混合溶液。本實施例中，將絕緣基材100置於 濃度為5摩爾/升（mol/L)之KOH溶液中處理5分鐘後取 出。最後，對處理後之絕緣基材100進行清洗。具體地， 8 201002162 .採用去離子水清洗絕緣基材100,去除表面11〇殘留之 KOH ’洗至表面no為接近中性。 藉由上述之處理，使得絕緣基材1〇〇表面之聚醯 亞胺中之醯亞胺鍵於強鹼性條件下斷開形成羧基與醯胺 鍵，羧基與醯胺基之親水性強於醯亞胺基，從而改善了絕 緣基材⑽表面110之親水性。同時，生成之幾基㈣吸 附陽離子’於KOH溶液中，其可吸附κ+。 第二步：將含有可溶性鈀鹽之油墨印刷於親水處理過 之絕緣基材100之表面11〇，形成線路圖形2〇〇。 如圖2所示，分別於該絕緣基材100之表面110形成 線路圖形200。線路圖形可藉由喷墨列印或平版印刷等 方式形成於絕緣基材⑽之表面11〇。以喷墨列印為例，喷 墨列印系統於控制器之控制下根據所需製作之導電線路之 =形=油墨自喷嘴逐點喷灑到表面11〇，使沈積於表面 之/墨形成線路圖形200。該油墨形成之線路圖 與所需製作之導電線路之圖形相同。 越2把例中’知用之油墨為水溶性之纪鹽溶液。該鈀 =趟H夂把、氯化t、硝酸把、飽絡合物或其他可溶性 .. ，了提向氣化鈀之溶解性，於氯化鈀溶液中 化銨亂化釦與氣化鈀質量比可為1:1，氯化鈀與氣 化鉍可形成絡合物 、虱 可向該油墨中加入表面度。於製備過程中還 . /〖生Μ、黏度調節劑、連接料或i 他助劑，用以調節油黑少主 土之表面張力、黏度等性能，從而提 201002162 回油<土，、待列印或印刷物體表面之社人 為陰離子型、陽離+刑 、σ 口 。表面活性劑可 除離子型、非離子型等，連接料 聚乙烯醇等高分子姑挝 了叶j马水说s曰 加入口質百ΠΓ 據所需油墨之性能選擇性地 1二 為°.1%至2°%之連接料、。.1%至50%之黏 :二即/:二’1%至5〇%之保濕劑、〇.1%至5%之表面活性劑 及0.1%至10%之其他助劑。 經親水處理過之絕緣基材1〇〇之表面ιι〇吸附有卸離 子，列印於表面Π〇該油墨中> 子發生離土甲3有鈀離子，鉀離子與鈀離 =發生離子父換’使得把離子吸附到絕緣基材⑽之表面 中之le鹽以形 第三步：採用還原劑還原線路圖形200 成纪質預製線路300。 如圖3及圖4所示，將形成於絕緣基材表面⑽ 之線路圖形200轉變成預製線路3⑽。即’表面⑽上 j路/圖形200之輯子經化學反應，使把離子還原成絶單 質，從而於表面HQ上形成鈀質預製線路3〇〇 Ο 為了防止線路圖形2〇〇中鈀離子於離子性還原劑中產 生脫吸附與再吸附，導致線路之解析度下降之問題，本實 施例中，將鈀離子還原為單質鈀採用非離子還原劑進行還 原。具體之，採用液態有機還原劑或氣體還原劑。 對於還原性較強之液態有機還原劑，如甲醛與水合肼 等，可將絕緣基材100浸入其溶液中，於常溫或低溫狀態 下還原。以曱盤為例，於50攝氏度下，將表面11〇具有線 路圖形200之絕緣基材ι〇〇浸入曱醛溶液中15分鐘，取出 201002162 絕緣基材100後用去離子水清洗。 對於還原性較弱之液態有機還原劑，如丙酮、乙二醇 等，可於紫外光照之條件下，使得線路圖形200中之鈀離 子還原為單質鈀。以丙酮為例，將表面110具有線路圖形 200之絕緣基材100浸入丙酮溶液中紫外光照射6分鐘，取 出絕緣基材100後用去離子水清洗。以乙二醇與丙酮之混 合溶液為例，將表面110具有線路圖形200之絕緣基材100 浸入上述溶液中紫外光照射6分鐘，取出絕緣基材100後 用去離子水清洗。還可應用還原性氣體將鈀離子還原，該 還原性氣體為乙烯、一氧化碳與氫氣等。 第四步，於預製線路300之表面鍍覆金屬400形成導 電線路500，從而得到電路板50。 對於上一步驟中所得到之預製線路300,由於預製線路 300係藉由將鈀鹽環原為鈀單質而形成之線路，而該鈀鹽中 金屬離子間可能沒有完全結合，其連續性較差，當鈀離子 被還原為金屬鈀後所得到之預製線路300中，鈀將會以不 連續之粒子存於並組成預製線路300,預製線路300之導電 性將勢必受到影響。 因此，如圖5所示，於鈀制預製線路300之表面經過 電鍍或化學鍍之方法鍍覆金屬400，從而形成連續之導電線 路500。該鍍覆金屬可為銅、鎳或銀等。 具體地，將形成預製線路300之絕緣基材100置於化 學鍍銅溶液中，於50攝氏度之溫度下進行化學鍍銅2分 鐘，即可使預製線路300形成完全電連通之導電線路500。 11 201002162 導電線路500中之銅粒子之粒徑為50至150奈米。該鍍液 還可包括銅化合物、還原劑與絡合劑。銅化合物可為硫酸 銅、氯化銅等；還原劑可為甲醛、乙醛酸等；絡合劑可為 乙二胺四乙酸二鈉、酒石酸鉀鈉等。當然，還可於鍍液中 加入穩定劑、光亮劑等，以滿足化學鍍之需要。具體地， 該鍍銅溶液之組分為：硫酸銅10克/升（g/L)、酒石酸鉀鈉 22g/L、乙二胺四乙酸二鈉50g/L、曱醛15毫升/升（mL/L) 及曱醇10mL/L。 經過上述方法得到之導電線路500,其包括形成於絕緣 基材100親水性表面110之鈀質預製線路300,以及形成於 鈀質預製線路300表面且包覆預製線路300之鍍覆金屬 400 ° 對於上述方法形成之電路板50,其包括絕緣基材100、 鈀制預製線路300與鍍覆金屬400。該絕緣基材100之表面 110經過親水性處理之表面110為一親水性表面。該預製線 路300形成於親水性表面110，且與親水性表面110較好之 結合。該鍍覆金屬400形成於預製線路300之表面且包覆 預製線路300。 於電路板50之製作過程中，採用KOH將絕緣基材100 之表面110改性，提高了絕緣基材100表面110之親水性， 並且於絕緣基材100之表面110吸附了鉀離子，於形成線 路圖形200時，採用水溶性之含有鈀離子之油墨，提高了 表面110與油墨之結合能力，並且吸附之鉀離子與油墨中 之鈀離子產生離子交換，進一步增強了線路圖形200與絕 12 201002162 •緣基材1GG之表面11G之結合能力。後續之_子還原處 理中，採用非離子性還原劑，即有機還原劑與具有還原性 之無機氣體，改善了離子型還原劑（如獨氣化納、捧樣酸 鈉等）還原時，線路圖形200中之免離子之脫吸附愈再吸 ^而引起之線路解析度下降之問題。此外，於預製線路· 表面鑛覆金属_提高了導電線路·之導電性與連續性。 ^上所述’本發料已符合發㈣利之要件，遂依法 ^出專利申請。惟，以上所述者僅為本發明之較佳實施方 $ ’自不能以此㈣本案之申請專職圍。舉凡孰 ^之人士援依本發明之精神所作之等效修飾或變:，皆 應涵蓋於以下申請專利範圍内。 【圖式簡單說明】 圖1係本技術方案實施例提供電路板製作方法之 圖。 圖。圖2係本技術方案實施例提供之絕緣基材之結構示意 圖3係圖2中絕緣基材形成線路圖形之結構示意圖。 圖4係圖2中絕緣基材形成預製線路之結構示意圖。 一立圖5係圖2中絕緣基材形成導電線路之電路板之結構 13 201002162 【主要元件符號說明】 電路板 50 絕緣基材 100 表面 110 線路圖形 200 預製線路 300 鑛覆金屬 400 導電線路 500 14201002162 IX. Description of the Invention: [Technical Field] The present invention relates to the field of printed circuit board manufacturing, and in particular to a circuit board and a method of fabricating the same. [Prior Art] The use of inkjet printing technology to make conductive lines has received extensive attention in recent years. This method only needs to directly design the required line pattern from the computer, and then control the nozzle of the inkjet printing system by the controller. The ink particles are ejected from the nozzles and form a line pattern point by point. The line pattern can accurately control the position and width of the line. The method is a non-contact digital pattern process, which can reduce mutual pollution between different printing materials. Compared with the traditional circuit manufacturing method, it has the advantages of more simplified production process, low cost and low pollution. See literature: Murata, K.; Matsumoto, J.; Tezuka, A.; Oyama, K.; Matsuba, Υ·; Yokoyama, H.; Super fine wiring by inkjet printing Microprocesses and Nanotechnology Conference, ί 2004. Digest of Papers. 2004 International Oct. 27-29, 2004 Page(s): 24-25. A method of fabricating a conductive line by ink jet printing ink containing a soluble palladium salt and a weak reducing agent has been reported in the prior art. The method comprises the steps of: printing an inkjet ink with a soluble palladium ion and a weak reducing agent to print a palladium ion line pattern on the surface of the substrate, and then reducing the pattern on the line pattern by high-energy light to obtain a palladium line, but The adhesion of the line pattern on the surface of the substrate is not good. There is no reduced palladium ion in the circuit pattern and the reduced palladium 6 201002162 - the particles fall off into the chemical solution of the subsequent process, damaging the chemical solution, and - the line contains unreacted The reducing agent remains in the conductive line and has a great influence on the quality of the conductive line. Therefore, it is necessary to provide a method of manufacturing a circuit board to improve the adhesion of the conductive line to the surface of the substrate and improve the quality of the conductive line. SUMMARY OF THE INVENTION A circuit board and a method of fabricating the same will be described below by way of embodiments. A method for manufacturing a circuit board comprises: performing hydrophilic treatment on a surface of an insulating substrate; printing an ink containing a soluble salt on a surface of a hydrophilically treated insulating substrate to form a line pattern; and using a non-ionic reducing agent to restore the line pattern The salt is formed to form a prefabricated line; the surface of the prefabricated line is plated with metal to form a conductive line. A circuit board includes: an insulating substrate having a hydrophilic surface on which a prefabricated line is formed to cover the prefabricated line. Electric * * Compared to the prior art, the circuit board can be used to enhance the bonding ability of the circuit to the surface of the rim substrate. In the subsequent ion reduction treatment, a non-reducing reducing agent, that is, an organic reducing agent and a reducing gas are used. The use of ionic reducing agents (such as degassing sodium, sodium sulphate, etc.) also reduces the problem of degrading the line caused by desorption and resorption of ions in the circuit. [Embodiment] 7 201002162 The circuit board provided by the embodiment of the present technical solution and the manufacturing method thereof will be further described in detail below with reference to the accompanying drawings and embodiments. Referring to FIG. 1, the manufacturing method of the circuit board provided in this embodiment includes the following steps: In the first step, the surface 100 of the insulating substrate 100 is subjected to hydrophilic treatment. As shown in FIG. 2, in the embodiment, the insulating substrate 100 may be an insulating layer when a single layer is formed, or may be an insulating layer pressed on the surface of the multilayer circuit board during the manufacturing process of the multilayer circuit board. The material of the insulating substrate 100 is usually a polyimine-based material. In the present embodiment, the insulating substrate 100 is an insulating layer that requires a single-sided wiring. The insulating substrate 100 has a surface 110 for forming a conductive line. The material of the insulating substrate 100 is polyimide. The surface 110 of the insulating substrate 100 is hydrophilically treated to facilitate the ability of the surface 110 to bond ink during subsequent line fabrication. There are various ways to increase the hydrophilicity of the surface 110, such as modifying the polymer of the insulating substrate 100 such that the surface 110 forms a polar functional group. In the present embodiment, the surface 110 of the insulating substrate 100 is subjected to a hydrophilic treatment using an alkaline solution. The treatment of the surface of the insulating substrate 100 includes the following steps: First, the surface 110 of the insulating substrate 100 is cleaned. A solvent such as acetone, ethanol or water may be used for cleaning to remove dirt, oxides, grease and the like adhering to the surface 110. Then, the surface 110 of the insulating substrate 100 is treated with a strong alkaline solution. The strongly alkaline solution may be a KOH solution or a mixed solution of KOH and KMn04. In the present embodiment, the insulating substrate 100 was taken out in a KOH solution having a concentration of 5 mol/liter (mol/L) for 5 minutes, and then taken out. Finally, the treated insulating substrate 100 is cleaned. Specifically, 8 201002162. The insulating substrate 100 is cleaned with deionized water, and the residual KOH of the surface 11 去除 is removed until the surface no is near neutral. By the above treatment, the sulfhydrylene bond in the polyimine on the surface of the insulating substrate 1 is broken under strong alkaline conditions to form a carboxyl group and a guanamine bond, and the carboxyl group and the guanamine group are more hydrophilic than the guanamine group. The quinone imine group improves the hydrophilicity of the surface 110 of the insulating substrate (10). At the same time, the resulting base (d) adsorbs the cations in the KOH solution, which adsorbs κ+. The second step: printing an ink containing a soluble palladium salt on the surface 11 of the hydrophilically treated insulating substrate 100 to form a wiring pattern 2〇〇. As shown in FIG. 2, a line pattern 200 is formed on the surface 110 of the insulating substrate 100, respectively. The wiring pattern can be formed on the surface 11 of the insulating substrate (10) by ink jet printing or lithography. Taking inkjet printing as an example, the inkjet printing system is sprayed under the control of the controller according to the desired shape of the conductive line = ink is sprayed from the nozzle to the surface 11 逐 to form the ink deposited on the surface. Line graphic 200. The wiring pattern formed by the ink is the same as the pattern of the conductive traces to be fabricated. The more the 2 known inks are the water-soluble salt solution. The palladium = 趟H夂, chlorinated t, nitric acid, saturated complex or other soluble.., the solubility of the palladium to the palladium chloride solution in the palladium chloride solution The mass ratio may be 1:1, palladium chloride and vaporized ruthenium may form a complex, and ruthenium may add a surface degree to the ink. In the preparation process also / / Μ Μ, viscosity modifier, binder or i auxiliaries, to adjust the surface tension, viscosity and other properties of the oil black less soil, so that 201002162 oil return < soil, and The people who print or print the surface of the object are anionic, cation, punishment, and σ. The surfactant can be deionized, non-ionic, etc., and the polymer such as polyvinyl alcohol is used as a binder. The leaf j is said to be added to the oral cavity. According to the performance of the desired ink, the selectivity is 1 and 2. 1% to 2% of the binder. .1% to 50% stickiness: two is /: two '1% to 5% by weight of humectant, 〇. 1% to 5% of surfactant and 0.1% to 10% of other auxiliaries. The surface of the hydrophilically treated insulating substrate 1 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 〇 The change is made to cause the ions to be adsorbed into the surface of the insulating substrate (10) to form a third step: the reducing pattern is used to reduce the line pattern 200 into a precursor pre-made line 300. As shown in FIGS. 3 and 4, the line pattern 200 formed on the surface (10) of the insulating substrate is converted into the prefabricated line 3 (10). That is, the surface of the j-channel/pattern 200 on the surface (10) is chemically reacted to reduce the ions into a simple substance, thereby forming a palladium pre-fabricated line on the surface HQ. 3D in order to prevent palladium ions in the line pattern 2 Desorption and re-adsorption are generated in the ionic reducing agent, which causes a problem that the resolution of the line is lowered. In the present embodiment, the palladium ion is reduced to elemental palladium by reduction with a nonionic reducing agent. Specifically, a liquid organic reducing agent or a gas reducing agent is used. For a liquid metal reducing agent having a relatively high reductive property, such as formaldehyde and hydrazine hydrate, the insulating substrate 100 can be immersed in the solution and reduced at normal temperature or low temperature. Taking the disk as an example, the insulating substrate ι having the surface pattern 200 was immersed in the furfural solution for 15 minutes at 50 degrees Celsius, and the 201002162 insulating substrate 100 was taken out and washed with deionized water. For a less-reducing liquid organic reducing agent, such as acetone, ethylene glycol, etc., the palladium ions in the line pattern 200 can be reduced to elemental palladium under ultraviolet light. Taking acetone as an example, the insulating substrate 100 having the wiring pattern 200 on the surface 110 is immersed in an acetone solution for ultraviolet light for 6 minutes, and the insulating substrate 100 is taken out and washed with deionized water. Taking a mixed solution of ethylene glycol and acetone as an example, the insulating substrate 100 having the wiring pattern 200 on the surface 110 is immersed in the above solution for ultraviolet light irradiation for 6 minutes, and the insulating substrate 100 is taken out and washed with deionized water. The palladium ion can also be reduced by using a reducing gas such as ethylene, carbon monoxide, hydrogen or the like. In the fourth step, the metal 400 is plated on the surface of the prefabricated line 300 to form the conductive line 500, thereby obtaining the circuit board 50. For the prefabricated line 300 obtained in the previous step, since the prefabricated line 300 is formed by the palladium salt ring as a palladium element, the metal ions in the palladium salt may not be completely combined, and the continuity is poor. In the prefabricated line 300 obtained after the palladium ions are reduced to metallic palladium, the palladium will be present as discrete particles and constitute the prefabricated line 300, and the conductivity of the prefabricated line 300 will be affected. Therefore, as shown in Fig. 5, the metal 400 is plated on the surface of the palladium prefabricated line 300 by electroplating or electroless plating to form a continuous conductive line 500. The plating metal may be copper, nickel or silver. Specifically, the insulating substrate 100 forming the prefabricated wiring 300 is placed in a chemical copper plating solution, and electroless copper plating is performed at a temperature of 50 ° C for 2 minutes to form the electrically conductive line 500 in which the prefabricated wiring 300 is completely electrically connected. 11 201002162 The copper particles in the conductive line 500 have a particle size of 50 to 150 nm. The plating solution may further include a copper compound, a reducing agent, and a complexing agent. The copper compound may be copper sulfate, copper chloride or the like; the reducing agent may be formaldehyde, glyoxylic acid or the like; the complexing agent may be disodium edetate, sodium potassium tartrate or the like. Of course, stabilizers, brighteners, etc. can also be added to the plating solution to meet the needs of electroless plating. Specifically, the composition of the copper plating solution is: copper sulfate 10 g / liter (g / L), sodium potassium tartrate 22 g / L, disodium edetate 50 g / L, furfural 15 ml / liter (mL /L) and sterol 10mL/L. The conductive line 500 obtained by the above method comprises a palladium prefabricated line 300 formed on the hydrophilic surface 110 of the insulating substrate 100, and a plated metal formed on the surface of the palladium prefabricated line 300 and covering the prefabricated line 300. The circuit board 50 formed by the above method includes an insulating substrate 100, a palladium prefabricated line 300, and a plated metal 400. The surface 110 of the surface 110 of the insulating substrate 100 subjected to the hydrophilic treatment is a hydrophilic surface. The preformed line 300 is formed on the hydrophilic surface 110 and is preferably combined with the hydrophilic surface 110. The plated metal 400 is formed on the surface of the prefabricated line 300 and covers the prefabricated line 300. During the fabrication of the circuit board 50, the surface 110 of the insulating substrate 100 is modified with KOH to improve the hydrophilicity of the surface 110 of the insulating substrate 100, and the potassium ions are adsorbed on the surface 110 of the insulating substrate 100 to form When the circuit pattern is 200, the water-soluble ink containing palladium ions is used to improve the bonding ability of the surface 110 and the ink, and the adsorbed potassium ions exchange ion exchange with the palladium ions in the ink, further enhancing the line pattern 200 and the absolute 12 201002162 • The bonding ability of the surface 11G of the edge substrate 1GG. In the subsequent _ sub-reduction treatment, a non-ionic reducing agent, that is, an organic reducing agent and a reducing inorganic gas, is used to improve the reduction of the ionic reducing agent (such as sodium sulphate, sodium sulphate, etc.). In the graph 200, the deionization of the ion-free desorption is further caused by the decrease in the resolution of the line. In addition, the prefabricated line and surface mineralized metal _ improve the conductivity and continuity of the conductive line. ^ The above mentioned 'issued materials have been in line with the requirements of the four (four), and the patent application is filed according to law. However, the above is only the preferred embodiment of the present invention. Equivalent modifications or variations made by persons in accordance with the spirit of the present invention are intended to be included within the scope of the following claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing a method of fabricating a circuit board according to an embodiment of the present technical solution. Figure. 2 is a schematic structural view of an insulating substrate provided by an embodiment of the present technical solution. FIG. 3 is a schematic structural view showing a circuit pattern formed by the insulating substrate of FIG. 4 is a schematic structural view of the insulating substrate forming a prefabricated line in FIG. Figure 5 is a structure of a circuit board in which an insulating substrate forms a conductive line in Fig. 2 201002162 [Description of main components] Circuit board 50 Insulating substrate 100 Surface 110 Line pattern 200 Prefabricated line 300 Mineral coated metal 400 Conductive line 500 14