200836278 九、發明說明 【發明所屬之技術領域】 本發明係關於半導體晶片之金凸塊或金配線形成用非 氰系金電鍍浴。此金電鍍浴可在矽或Ga/As化合物晶圓上 形成由表面平坦的金電鍍皮膜所成的金凸塊或金配線。 【先前技術】 非氰系金電鍍浴之基本浴係由作爲金鹽之亞硫酸鹼鹽 或亞硫酸金銨、作爲安定劑之水溶性胺、作爲結晶調整劑 之微量的T1化合物、P b化合物或A s化合物、作爲導電 鹽之亞硫酸鹽及硫酸鹽、和緩衝劑所構成。 藉由此非氰系金電鍍浴所形成之電鍍皮膜有優異的導 電性、熱壓合性等物理特性，耐氧化性、耐藥品性亦優異 。基於此理由，此鍍浴可較佳地適用於作爲半導體晶片的 電極之凸塊形成與配線形成等。 茲就半導體晶片之金凸塊之形成方法參照圖1所示之 半導體晶片的截面圖說明如下： 圖1中，1〇〇爲半導體晶片、2爲矽或Ga/As化合物晶 圓，於另一面（本圖中爲上面）形成有未圖示之1C線路。 於晶圓2之1C線路上形成有微小的A1電極4。形成有1C 線路之晶圓2上面與A1電極4之上面的邊緣係以鈍態膜6被 覆。在形成於A1電極4之上面中央之鈍態膜6的開口部7上 面及鈍態膜6上面，依序積層有用以被覆此等之TiW濺鍍 膜8、金濺鍍膜9。 -4- 200836278 如上述般，在矽或Ga/As化合物晶圓上，通常形成有 圖1所示般的鈍態膜。鈍態膜之目的在於使周圍之配線與 以金電鍍形成之金皮膜之間絕緣，並且保護周圍之配線。 鈍態膜之材質爲聚醯亞胺等樹脂及SiN等。 於金濺鍍膜9表面，如圖1所示般，爲具有在A1電極4 之邊緣部上方形成較中心部更往上***之封閉凸條1 〇之搗 缽狀的形狀。此形狀乃起因於形成於A1電極4上面周緣之 鈍態膜6之搗缽狀之形狀。金濺鍍膜9之凸條10的上端與位 於凸條1 0的中心位置之凹部底面1 1的段差X爲鈍態膜段差 〇 於金濺鍍膜9上形成有使用遮蔽材12形成的遮蔽圖案 。圖案化之遮蔽材12於A1電極4的上方有開口部14。於遮 蔽材12的開口部14內，藉由金電鍍形成金凸塊16。 藉由金電鍍形成於金濺鍍膜9上之金凸塊1 6，爲依照 金濺鍍膜9表面之形狀。因此，於金凸塊16表面產生有鈍 態膜段差所致之段差，成爲搗缽狀之形狀。 用具有以往的基本組成之非氰系金電鍍浴來形成金凸 塊之情況，由於前述鈍態膜6之突條所致之段差，得到的 金凸塊中會產生與鈍態膜段差相當之凹部20。 又，圖1中，1 8爲球狀之金球、焊球等之金屬球。於 金凸塊16上，附著有複數（本圖中爲2個）的金屬球18。 於有凹部20之金凸塊附著有金屬球18之情況，金屬球 18容易位於凹部20處。其結果，介在著此金屬球18將金線 熱壓合於金凸塊16時，金線與金屬球之接合會不充分。而 -5- 200836278 且，由於壓合面不平坦，故加壓變得不均一，致接合部無 法得到足夠之接合強度。 於基板之凸塊以倒裝晶片接合（flip chip bonding)來 搭載半導體晶片1 〇〇時，係使用泛用性接合材料之異向性 導電膜。異向性導電膜爲導電粒子均一地分散於環氧樹脂 等樹脂之中所成者。導電粒子爲在丙烯酸樹脂粒子表面依 序被覆鎳、金之粒子。於使基板之凸塊與半導體晶片用異 向性導電膜接合之情況，係夾著異向性導電膜將半導體晶 片壓合於基板之凸塊上。藉由此壓力，異向性導電膜內原 本相互分離之導電粒子可彼此密合，透過導電粒子使基板 之凸塊與半導體晶片成爲電性連接。 藉由金電鍍浴以形成金凸塊的方法乃公知者，例如， 用含有氰化金鉀之金電鍍浴的形成方法記載於日本專利特 開2003 -7762號公報（段落編號[002 1 ]、[0022])中。 【發明內容】 (發明所要解決之課題） 如上述般，於將半導體晶片組裝至基板中，係介在著 異向性導電膜進行接合，或介在著金屬球進行與金線之接 合。金凸塊、金配線之上部表面相當於與基板或金線之接 合面。其形狀，較佳者並非爲有搗缽狀等之凹凸的形狀， 而爲平坦的形狀。由於起因於鈍態膜段差之金凸塊或金配 線之接合面的凹部的深度及直徑較導電粒子或金屬球之粒 徑大，故於半導體晶片組裝至基板時會發生接合不良，致 -6 - 200836278 有產生電性缺陷之情況。 本發明係鑑於上述情況而提出者，目的在於提供可不 受鈍態膜段差之影響而形成皮膜表面凹凸差爲1 μηι以下 之平坦的金凸塊、金配線，於藉由異向性導電膜或金屬球 接合時可達到充分之接合強度所須之金凸塊或金配線形成 用非氰系金電鍍浴。 (用以解決課題之手段） 本發明者等，爲達成上述目的而一再進行硏究之結果 ，發現藉由在上述一般的非氰系金電鍍浴之基本組成中調 配入選自鈀鹽、鉑鹽、鋅鹽及銀鹽中之任一種以上以既定 的濃度調配，起因於鈍態膜之凹凸之金電鍍皮膜表面之凹 凸差可形成爲1 μηι以下。並得知此金皮膜有均一且緻密 的外觀、皮膜硬度、剪力強度特性，適於作爲半導體晶片 之凸塊、配線。 亦即，用以解決上述課題之本發明如下述： [1 ] 一種金凸塊或金配線形成用非氰系金電鍍浴，其 含有以金量計爲1〜20 g/L的亞硫酸金鹼鹽或亞硫酸金銨、 水溶性胺1〜30 g/L、以金屬濃度計爲〇·ι〜1〇0 mg/L的T1 化合物、Pb化合物或As化合物、以S03·2量計爲5〜100 g/L的亞硫酸鹽、以S04·2量計爲1〜120 g/L的硫酸鹽、緩 衝劑0.1〜3 0 g/L、與以金屬濃度計爲〇·；[〜；! 〇〇 mg/L的選自 鈀鹽、鉑鹽、鋅鹽及銀鹽中之任一種以上。 [2]—種金凸塊或金配線之形成方法，其係用[】]所記 200836278 載之金凸塊或金配線形成用非氰系金電鍍浴在經圖案化的 晶圓上進行金電鍍形成金凸塊或形成金配線。 (發明之效果） 本發明之非氰系金電鍍浴係於一般的非氰系金電鍍浴 之基本組成中含有既定量的鈀鹽、鉑鹽、鋅鹽或銀鹽。因 此，於形成金凸塊、金配線時，在其表面不會產生因鈍態 膜段差所致之凹凸。所得之金凸塊、金配線之皮膜表面的 凹凸差爲1 μηι以下。依據本發明，可於半導體晶片上形 成無段差之平坦的金皮膜表面之金凸塊、金配線。 藉由本發明所形成之金凸塊、金配線，均一且緻密， 外觀特性與皮膜硬度和剪力強度特性皆佳。 【實施方式】 本發明之金凸塊或金配線形成用非氰系金電鍍浴，係 於公知的金電鍍浴中含有選自鈀鹽、鉑鹽、鋅鹽及銀鹽中 之一種以上；所述公知的金電鑛浴爲由作爲金源之亞硫酸 金鹼鹽或亞硫酸金銨、作爲安定劑之水溶性胺、微量的結 晶調整劑、作爲導電鹽之亞硫酸鹽及硫酸鹽、與緩衝劑所 構成。 以下就本發明之金電鍍浴的必須成分之各成分逐一加 以說明。 (1)亞硫酸金鹼鹽、亞硫酸金銨（金源） 200836278 作爲本發明中所用之亞硫酸金鹼鹽，可使用公知之亞 硫酸金鹼鹽，並無特別限制。作爲亞硫酸金鹼鹽可舉出例 如亞硫酸金（I)鈉、亞硫酸金（I)鉀等。此等可1種單獨使用 ，亦可2種以上倂用。 本發明之金電鍍浴中，作爲金源係使用亞硫酸金鹼鹽 或亞硫酸金銨，其調配量，以金量計，通常爲1〜20 g/L， 以8〜15 g/L爲佳。亞硫酸金鹼鹽或亞硫酸金銨之調配量若 未滿1 g/L，會電鍍皮膜會不均一，致粗且脆，成爲所謂燒 焦鍍層（burnt deposits)之情況。若超過20 g/L，電鍍皮膜 之特性等雖無問題，但徒增成本。 (2)水溶性胺（安定劑） 作爲水溶性胺可使用例如：1，2 _二胺基乙烷、1，2 -二 胺基丙烷、1,6 -二胺基己烷等之二胺。此等可1種單獨使 用，亦可2種以上倂用。 水溶性胺之調配量通常爲1〜30 g/L，以4〜20 g/L爲佳 。水溶性胺之調配量若超過3 0 g/L，金屬鹽之安定性雖增 大，但得到之電鍍皮膜之硬度高、表面粗度會變小。其結 果，鍍金皮膜與金屬球或異向性導電膜之界面的接觸面積 會減小（亦即所謂之錨合（anchor)效果不充分），致接合強 度不足。而且，鑛金皮膜之熱處理後之硬度會大幅降低， 致與金配線或基板接合時會發生凸塊崩壞等不良情形。若 未滿1 g/L，界限電流密度會降低致產生鍍層燒焦之情形 200836278 (3 )T1化合物、Pb化合物、As化合物（結晶調整劑） 作爲本發明之金電鍍浴中所使用的結晶調整劑，可舉 出例如：乙酸鉈、丙二酸鉈、硫酸鉈、硝酸鉈等之T1化 合物；檸檬酸鉛、硝酸鉛、烷磺酸鉛等之Pb化合物；三 氧化二砷等之As化合物。此等T1化合物、Pb化合物、 As化合物可1種單獨使用，亦可組合2種以上使用。 結晶調整劑之調配量，可在無損於本發明之目的的範 圍內適當地使用，以金屬濃度計通常爲0.1〜100 mg/L，以 0.5〜50 g/L爲佳，以3〜25 g/L爲特佳。結晶調整劑之調配 量若超過100 mg/L，鑛層表面會有光澤面與非光澤狀表面 混在成不均一的狀態（電鍍包覆性變差）之情況。又，金會 成爲紊亂的大粒子析出致外觀產生斑駁狀，或因結晶調整 劑之過度共析導致金皮膜剝離之情況。此等會成爲接合不 良的原因。結晶調整劑之調配量若未滿0.1 mg/L，會有電 鍍包覆性、鍍浴安定性及耐久性會變差，抑或鍍浴分解之 情況。 (4)亞硫酸鹽、硫酸鹽（導電鹽） 本發明中作爲導電鹽使用之亞硫酸鹽、硫酸鹽可舉出 例如：亞硫酸鈉、亞硫酸鉀、焦亞硫酸鈉、亞硫酸氫鈉等 之亞硫酸鹽；硫酸鈉等之硫酸鹽。其中尤以亞硫酸鈉與硫 酸鈉之組合爲佳。 作爲本發明之金電鍍浴中之上述亞硫酸鹽及硫酸鹽之 -10- 200836278 調配量，可在無損於本發明之目的的範圍內適當地 惟以以下之調配量爲佳。 亞硫酸鹽，以S〇r2量計，通常定爲5〜100 g 10〜8 0 g/L爲佳，以20〜6 0 g/L爲特佳。亞硫酸鹽之 若未滿5 g/L，包覆性及液安定性會變差，會有鍍 之情況。若超過1〇〇 g/L，界限電流會降低會有產 燒焦之情形。 硫酸鹽，以S Ο厂2量計，通常定爲1〜1 2 0 g / L， g/L爲佳，以1〜4 0 g/L爲特佳。若未滿lg/L，會有 皮膜於熱處理後之硬度會過高，致凸塊與基板之接 ，或液安定性變差致鍍浴發生分解之情況。若趕 g/L，會有界限電流密度會降低致發生鍍層燒焦之惰 (5)緩衝劑 作爲本發明中所用之緩衝劑，只要是通常金電 所使用者皆可，並無特別限定，可使用例如：磷酸 酸鹽等無機酸鹽；檸檬酸、苯二甲酸鹽、乙二胺四 等之有機酸（羧酸、羥羧酸）鹽等。尤以磷酸鹽爲特^ 本發明之非氰系金電鍍浴中之緩衝劑的調配量 爲1〜30 g/L，以1〜20 g/L爲佳，以2〜15 g/L爲特佳 劑之調配量若未滿0.1 g/L，pH會降低，液安定性 ，會有發生鍍浴成分分解之情況。若超過30 g/L， 限電流密度降低，致發生鍍層燒焦之情況。 設定， /L，以 調配量 浴分解 生鍍層 以1〜60 形成的 合不良 ί 過 120 :形。 鍍浴中 鹽、硼 醋酸鹽 • 〇 通常定 。緩衝 會變差 會有界 -11 - 200836278 (6)鈀鹽、鉑鹽、鋅鹽及銀鹽 作爲調配於本發明之非氰系金電鍍浴之鈀鹽，可舉& 四胺鈀氯化物鹽、四胺鈀硫酸鹽等。 作爲調配於本發明之非氰系金電鍍浴之鉑鹽，可舉& 四胺鉑氯化物與乙二胺配位鹽等。 作爲調配於本發明之非氰系金電鍍浴之鋅鹽，可舉& 鋅胺配位鹽等。 作爲調配於本發明之非氰系金電鍍浴之銀鹽，可舉出 硫代硫酸銀鹽等。 鈀鹽、鉑鹽、鋅鹽及銀鹽可單獨使用任1種，亦可2種 以上倂用。 本發明之非氰系金電鍍浴中之鈀鹽、鉑鹽、鋅鹽及銀 鹽之調配量定爲此等金屬鹽之合計金屬濃度0.1〜200 mg/L ，以0.1〜100 mg/L爲佳，以0.1〜25 mg/L爲特佳。 於用本發明之非氰系金電鍍浴藉由電鍍在矽晶圓、化 合物晶圓上進行凸塊、配線等之金電鍍時，可依循通常方 法進行電鍍操作。例如，首先在形成於晶圓上之IC線路 表面藉由濺鍍形成A1電極。然後，依序形成作爲底層金 屬膜之Ti-W濺鍍膜、Au濺鍍膜。然後，在此晶圓上用遮 蔽劑進行遮蔽。然後，以晶圓作爲被鍍物進行金電鍍。最 後，自晶圓將遮蔽材、未被覆金凸塊與金配線的部分之底 層金屬膜除去。作爲除去遮蔽材之方法可例示使其溶解於 溶劑中除去的方法等。作爲除去底層金屬膜之方法，可例 示用過氧化氫溶劑、王水溶劑等剝離的方法。 -12- 200836278 遮蔽劑中，作爲酚醛清漆系正型光阻劑可舉出例如市 售品之LA-900、HA-900、作爲丙烯酸系負型光阻劑，可 舉出例如BMR C- 1 000(以上爲東京應化工業（股）製）等。 電鍍浴溫度通常爲40〜70 °C，以50〜65 °C爲佳。鍍浴溫 度若未滿40 °C，會因電流效率降低致析出不均一，而有電 鍍皮膜之膜厚與表面狀態不均一的情況。又，亦會有因鍍 浴之導電性降低致電壓上昇而使鍍浴分解之情況。鍍浴溫 度若超過70 °C，會有析出之金會生長成大粒子而形成皮膜 ，使得電鍍皮膜表面成爲無光澤面狀之情況，或因鍍浴溫 度高致使金配位鹽分解之情況。 電流密度，於金濃度爲8〜15 g/L、60 °C之鍍浴溫度之 情況，通常爲2.0 A/dm2以下，以0.1〜1.5 A/dm2爲佳，以 0.3〜0.8 A/dm2爲特佳。電流密度若超出上述範圍，會有析 出樹枝狀之皮膜，或因施加高電壓而使金屬配位體分解之 情形。電流密度若低於上述範圍，生產性會降低。且會有 析出之金粒子會粗大化、鑛層表面呈無光澤（mat)狀而不 適於與金配線之接合的情形。 作爲本發明之非氰系金電鍍浴之pH，通常爲7.0以上 ，以7.2〜10.0爲佳。非氰系金電鍍浴之pH若未滿7.0，會 有鍍浴相當不安定致鍍浴分解之情形。另一方面，若PH 超過1 0.0，會有遮蔽劑溶解致污染電鍍皮膜之情形，或因 光阻劑圖案消失導致無法形成所要形狀的金凸塊的情形。 本發明之非氰系金電鍍浴中，可於無損於本發明之目 的之範圍內適當地使用P Η調整劑等之其他成分。 -13- 200836278 作爲pH調整劑，可舉出例如：稀硫酸水、亞硫酸水 、磷酸等之酸、氫氧化鈉、氫氧化鉀、氨水等之鹼。 本發明之非氰系金電鍍浴，藉由補充管理作爲金源之 亞硫酸金鹼鹽等及構成鑛浴中之其他成分，可達成2循環（ 以鍍浴中之金量全部消費之情形作爲1循環）以上之使用。 作爲可用本發明之非氰系金電鍍浴電鍍之被鍍物，只 要是素材經金屬化賦予導電性者皆可，並無特別限制。尤 其特別適合於，例如，在使用酚醛清漆系正型光阻劑或丙 烯酸系負型光阻劑作爲遮蔽劑進行圖案化之矽晶圓上或 Ga/As晶圓上形成凸塊與配線等之情況。 [實施例] (實施例1〜6、比較例1〜2) 調製表1〜2所示之配方之非氰系金電鍍浴。各原料之 調配濃度之單位，若無特別指明，爲g/L。惟Na3Aii(S03)2係 以Au量、Na2S〇3係以S03量、Na2So4係以S04量之濃度表 不 ° 作爲被鍍物係用形成有1C線路之矽晶圓。此矽晶圓 有藉由酚醛清漆系正型光阻劑圖案化之凸塊開口部。矽晶 圓之基材截面組成爲金濺鍍膜/TiW濺鍍膜/鈍態膜/A1電 極/Si02· Si。其截面圖示於圖2(A)。圖2(A)中，22爲遮蔽 劑（光阻劑）、24爲金濺鍍膜、25爲TiW濺鍍膜、26爲鈍態 膜、28爲矽晶圓、30爲A1電極。 將被鍍物浸漬於調製之非氰系金電鍍浴1 L中，藉由 -14- 200836278 進行通電形成18 μπι膜厚之電鍍皮膜。又，非氰系金電鍍 浴之電流效率在一般的電鍍操作下通常爲100%。 於形成既定膜厚的皮膜後，將遮蔽劑除去，就形成的 凸塊表面之段差程度、浴安定性、電鍍皮膜外觀、皮膜硬 度（未處理及30(TC、30分鐘熱處理後）、用碘系蝕刻劑之 蝕刻性，以下述方法及基準進行評價。結果一倂示於表 [凸塊皮膜表面之段差的程度（μιη)] 就圖2(A)所示之鈍態膜段差a用觸針式輪廓描繪器 (KLA-TENKOR 公司製，Profiler-P15)測定，得 1·5 μηι。 如圖2(B)所示般，用實施例1〜6及比較例1、2之鍍浴 形成金凸塊34。然後以專用溶劑甲乙酮將遮蔽材22(酚醛 清漆系正型光阻劑）溶解。用觸針式輪廓描繪器測定，以 金凸塊34之邊端部之最大高度値與中央部之最小高度値的 差b作爲凸塊表面之段差（μπι)。 又’作爲凸塊所要求的特性之段差通常爲1 μηι以下 。又，於使用不含鈀鹽、鉑鹽、鋅鹽及銀鹽之任一種之通 常的鍍浴在同樣的被鍍物上形成金凸塊之情況，凸塊表面 之電鍍後段差（μπι)較起因於電鍍前之鈍態膜之段差（μηι)大 [浴安定性] 在被鍍物上進行電鍍後，觀察鍍浴的情形，依據下述 -15- 200836278 基準進行評價： 分解：鍍液分解。 X:鍍浴中金的沈澱用肉眼可觀察到之程度。 △:鍍浴中金的沈澱無法看出。以0·2 μπι之透析膜過 濾器過濾鍍浴1 000 mL之下可目視觀察到沈澱之程度。 〇：鍍浴中無法觀察到金的沈澱。 [電鍍皮膜外觀] 就形成於被鏟物上之金凸塊之表面皮膜外觀以目視觀 察及光學顯微鏡觀察，依據下述基準進行評價： X :色調偏紅，可看到樹枝狀析出之斑駁情形，或發 生鍍層燒焦情形。 △:無異常析出，爲光澤性外觀。 〇：色調爲檸檬黃色，爲無光澤〜半光澤之均一外觀 [皮膜硬度（維氏硬度；Hv)] 用形成於被鍍物上之特定凸塊部位，以維氏硬度計測 定其皮膜硬度（未熱處理及300 °C 30分鐘熱處理後）。 通常作爲凸塊電鍍用途所要求之特性，熱處理後之皮 膜硬度爲60 Hv以下。又，測定條件係以測定壓子爲25 gf 保持10秒爲條件。 [碘系蝕刻劑之Ail凸塊之均一蝕刻性] -16- 200836278 使被鍍物浸漬於在常溫下經充分攪拌的碘系蝕刻劑中 9 0秒鐘後，醇系沖洗液清洗，再以乙醇噴霧，以吹風機乾 燥。然後，用光學顯微鏡以50〜150之放大倍率觀察形成於 被鍍物上之全部凸塊的表面狀態，依據下述基準針對斑駁 情形之有無進行評估。此處，所謂「斑駁」係指於蝕刻時 選擇性地溶解的部分與不溶解之部分混合存在的狀套。 X :於5 0%以上之凸塊表面可觀察到斑駁情形。 △:僅於部分區域之凸塊表面可觀察到斑駁情形。 〇：於被鍍物之全部凸塊表面皆無法觀察到斑駁情形 [綜合評價] 由上述各評價結果依據下述評價基準進行評價： X :有關形成之金電鍍皮膜（金凸塊）及電鍍處理後之 非氰系金電鍍浴之上述評價結果中含有不佳之結果。 〇：有關形成之金電鍍皮膜（金凸塊）及電鍍處理後之 非氰系金電鍍浴之上述評價結果全部爲良好之結果。 -17- 200836278 [表1 ] 實方 酬 1 2 3 4 5 6 電鍍條件 電鍍溫度(°c) 60 60 60 60 60 60 電流密度(A/dm2) 0.5 0.5 0.5 0.4 0.6 0.5 電鍍時間(分） 58 58 58 58 58 58 配方濃度(g/L) Na3Au(S03)2WAii 計 10 10 10 10 10 10 Na2So3以 S03計 40 40 40 40 30 30 Na2So4以 S04計 10 10 10 10 30 30 1，2-二胺基乙烷 4 4 4 4 15 15 Tl(mg/L) 15 15 15 15 15 15 緩衝劑A 15 15 15 15 - - 緩衝劑B - - - - 5 5 鈀鹽(mg/L以Pd計） 7 - - - 5 一 鉑鹽(mg/L以Pt計） - 5 - - - 7 鋅鹽(mg/L以Ζιι計） - - 15 - - - 銀鹽(mg/L以Ag計） • 一 • 10 _ 編 凸塊表面之段差(μηι) 0.14 0.48 0.15 0.50 0.10 0.12 鍍浴安定性 〇 〇 〇 〇 〇 〇 電鍍皮膜外觀 〇 〇 〇 〇 〇 〇 皮膜硬度未熱處理(Ην) 105 112 115 110 121 123 皮膜硬度30(TC熱處理後(Ην) 48 47 46 47 47 48 蝕刻性 〇 〇 〇 〇 〇 〇 綜合評價 〇 〇 〇 〇 〇 〇 -18- 200836278 [表2]BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-cyanide gold plating bath for forming a gold bump or a gold wiring of a semiconductor wafer. This gold plating bath can form gold bumps or gold wiring formed of a gold plating film having a flat surface on a tantalum or Ga/As compound wafer. [Prior Art] The basic bath of the non-cyanide gold plating bath is a sulfite alkali salt or a gold ammonium sulfite as a gold salt, a water-soluble amine as a stabilizer, a trace amount of a T1 compound, a Pb compound as a crystal modifier. Or a s compound, a sulfite and a sulfate as a conductive salt, and a buffer. The plating film formed by the non-cyanide gold plating bath has excellent physical properties such as electrical conductivity and thermocompression, and is excellent in oxidation resistance and chemical resistance. For this reason, the plating bath can be preferably applied to bump formation, wiring formation, or the like as an electrode of a semiconductor wafer. Referring to the cross-sectional view of the semiconductor wafer shown in FIG. 1 for the method of forming the gold bump of the semiconductor wafer, the following is a schematic view: In FIG. 1, 1 is a semiconductor wafer, 2 is a germanium or a Ga/As compound wafer, and the other side is on the other side. (Upper in the figure) A 1C line (not shown) is formed. A minute A1 electrode 4 is formed on the 1C line of the wafer 2. The upper surface of the wafer 2 on which the 1C line is formed and the upper surface of the A1 electrode 4 are covered with a passive film 6. On the upper surface of the opening portion 7 of the passive film 6 formed at the center of the upper surface of the A1 electrode 4 and the upper surface of the passive film 6, a TiW sputtering film 8 and a gold sputtering film 9 for coating the same are sequentially laminated. -4- 200836278 As described above, a passivation film as shown in Fig. 1 is usually formed on a germanium or Ga/As compound wafer. The purpose of the passive film is to insulate the surrounding wiring from the gold film formed by gold plating and to protect the surrounding wiring. The material of the passive film is a resin such as polyimine and SiN. As shown in Fig. 1, the surface of the gold sputter film 9 has a shape in which a closed ridge 1 隆 which is raised upward from the center portion of the edge portion of the A1 electrode 4 is formed. This shape is caused by the shape of the meandering film 6 formed on the upper periphery of the A1 electrode 4. The step X of the upper end of the ridge 10 of the gold sputter film 9 and the bottom surface 11 of the recess at the center of the ridge 10 is a passive film step. The gold sputter film 9 is formed with a mask pattern formed using the mask member 12. The patterned masking material 12 has an opening 14 above the A1 electrode 4. Gold bumps 16 are formed by gold plating in the opening portion 14 of the masking material 12. The gold bumps 16 formed on the gold sputter film 9 by gold plating are in accordance with the shape of the surface of the gold sputter film 9. Therefore, a step caused by a blunt film step difference is formed on the surface of the gold bump 16 to have a meander shape. In the case where a gold bump is formed by a non-cyanide gold plating bath having a conventional basic composition, a step difference due to the protrusion of the passive film 6 causes a difference in the resulting gold bump to be inferior to the passive film step. The recess 20 is. Further, in Fig. 1, 18 is a spherical metal ball or a metal ball such as a solder ball. On the gold bumps 16, a plurality of metal balls 18 (two in the figure) are attached. In the case where the metal bumps 18 are attached to the gold bumps having the recesses 20, the metal balls 18 are easily located at the recesses 20. As a result, when the metal ball 18 thermally presses the gold wire to the gold bump 16, the bonding of the gold wire and the metal ball is insufficient. Further, -5-200836278, since the press-fit surface is not flat, the pressurization becomes uneven, so that the joint portion cannot obtain sufficient joint strength. When the semiconductor wafer 1 is mounted on the bump of the substrate by flip chip bonding, an anisotropic conductive film of a general-purpose bonding material is used. The anisotropic conductive film is one in which conductive particles are uniformly dispersed in a resin such as an epoxy resin. The conductive particles are particles in which nickel or gold is coated on the surface of the acrylic resin particles in this order. In the case where the bump of the substrate is bonded to the semiconductor wafer with the anisotropic conductive film, the semiconductor wafer is pressed against the bump of the substrate with the anisotropic conductive film interposed therebetween. By this pressure, the conductive particles which are originally separated from each other in the anisotropic conductive film can be in close contact with each other, and the bumps of the substrate are electrically connected to the semiconductor wafer through the conductive particles. A method of forming a gold bump by a gold plating bath is known, for example, a method of forming a gold plating bath containing gold potassium cyanide is described in Japanese Patent Laid-Open No. 2003-7762 (paragraph No. [002 1], [0022] in. SUMMARY OF THE INVENTION (Problems to be Solved by the Invention) As described above, when a semiconductor wafer is assembled to a substrate, bonding is performed via an anisotropic conductive film or a metal ball is bonded to a gold wire. The upper surface of the gold bump and the gold wiring corresponds to the surface to be bonded to the substrate or the gold wire. The shape is preferably a shape that is not flat and has a flat shape. Since the depth and diameter of the concave portion of the joint surface of the gold bump or the gold wiring which are caused by the passive film step are larger than the particle diameter of the conductive particles or the metal ball, joint failure occurs when the semiconductor wafer is assembled to the substrate, and -6 - 200836278 There are cases of electrical defects. The present invention has been made in view of the above circumstances, and it is an object of the invention to provide a flat gold bump or a gold wiring which is formed to have a film surface unevenness of 1 μm or less without being affected by a passive film step difference, by an anisotropic conductive film or A non-cyanide gold plating bath for forming gold bumps or gold wirings required for sufficient bonding strength when metal balls are joined. (Means for Solving the Problem) As a result of repeated investigations to achieve the above object, the present inventors have found that a palladium salt or a platinum salt is blended in the basic composition of the above-mentioned general non-cyanide gold plating bath. Any one or more of the zinc salt and the silver salt may be formulated at a predetermined concentration, and the unevenness of the surface of the gold plating film caused by the unevenness of the passive film may be 1 μm or less. It was found that the gold film has a uniform and dense appearance, film hardness, and shear strength characteristics, and is suitable as a bump or wiring for a semiconductor wafer. That is, the present invention for solving the above problems is as follows: [1] A non-cyanide gold plating bath for forming gold bumps or gold wires, which contains gold sulfite in an amount of 1 to 20 g/L in terms of gold. a base salt or a gold ammonium sulfite, a water-soluble amine of 1 to 30 g/L, a T1 compound, a Pb compound or an As compound having a metal concentration of 〇·ι 〜1〇0 mg/L, in terms of S03·2 5 to 100 g/L of sulfite, 1 to 120 g/L of sulfate in terms of S04·2, buffer of 0.1 to 30 g/L, and metal concentration: 〜·; 〇〇mg/L is selected from any one or more selected from the group consisting of a palladium salt, a platinum salt, a zinc salt, and a silver salt. [2]—Formation method for gold bumps or gold wirings, which are formed on a patterned wafer by a non-cyanide gold plating bath using gold bumps or gold wirings as described in []] 200836278 Electroplating forms gold bumps or forms gold wiring. (Effects of the Invention) The non-cyanide-based gold plating bath of the present invention contains a predetermined amount of a palladium salt, a platinum salt, a zinc salt or a silver salt in a basic composition of a general non-cyanide-based gold plating bath. Therefore, when gold bumps and gold wiring are formed, irregularities due to a passive film step are not generated on the surface. The unevenness of the surface of the obtained gold bump and gold wiring film was 1 μηι or less. According to the present invention, gold bumps and gold wirings having a flat gold film surface without a step can be formed on a semiconductor wafer. The gold bumps and gold wires formed by the present invention are uniform and compact, and the appearance characteristics and film hardness and shear strength characteristics are good. [Embodiment] The non-cyanide gold plating bath for forming gold bumps or gold wires of the present invention contains one or more selected from the group consisting of a palladium salt, a platinum salt, a zinc salt, and a silver salt in a known gold plating bath; The well-known gold-electric ore bath is a gold sulfite alkali salt or a gold ammonium sulfite, a water-soluble amine as a stabilizer, a trace amount of a crystal modifier, a sulfite and a sulfate as a conductive salt, and It is composed of a buffer. Hereinafter, each component of the essential component of the gold plating bath of the present invention will be described one by one. (1) Gold sulfite alkali salt, gold ammonium sulfite (gold source) 200836278 As the gold sulfite salt used in the present invention, a known gold sulfite salt can be used, and it is not particularly limited. The gold sulfite alkali salt may, for example, be gold (I) sodium sulfite or potassium (I) sulfite. These may be used alone or in combination of two or more. In the gold plating bath of the present invention, gold base sulfite or gold ammonium sulfite is used as a gold source, and the amount thereof is usually 1 to 20 g/L in terms of gold, and is 8 to 15 g/L. good. If the amount of the gold sulfite alkali salt or the gold ammonium sulfite is less than 1 g/L, the plating film may be uneven, coarse and brittle, and it may become a so-called burnt deposit. If it exceeds 20 g/L, the characteristics of the plating film and the like are not problematic, but the cost is increased. (2) Water-soluble amine (stabilizer) As the water-soluble amine, for example, a diamine such as 1,2-diaminoethane, 1,2-diaminopropane or 1,6-diaminohexane can be used. . These may be used alone or in combination of two or more. The amount of the water-soluble amine is usually 1 to 30 g/L, preferably 4 to 20 g/L. When the amount of the water-soluble amine is more than 30 g/L, the stability of the metal salt is increased, but the hardness of the obtained plating film is high and the surface roughness is small. As a result, the contact area of the interface between the gold plating film and the metal ball or the anisotropic conductive film is reduced (i.e., the so-called anchor effect is insufficient), resulting in insufficient bonding strength. Further, the hardness of the gold film after heat treatment is greatly reduced, and defects such as bump collapse occur when the gold wiring or the substrate is joined. If it is less than 1 g/L, the limit current density is lowered to cause the plating to burn. 200836278 (3) T1 compound, Pb compound, As compound (crystal modifier) is used as the crystal adjustment used in the gold plating bath of the present invention. The agent may, for example, be a T1 compound such as barium acetate, barium malonate, barium sulfate or barium nitrate; a Pb compound such as lead citrate, lead nitrate or lead alkanesulfonate; or an As compound such as arsenic trioxide. These T1 compounds, Pb compounds, and As compounds may be used alone or in combination of two or more. The amount of the crystallization modifier can be suitably used within the range not detracting from the object of the present invention, and is usually 0.1 to 100 mg/L in terms of metal concentration, preferably 0.5 to 50 g/L, and 3 to 25 g. /L is especially good. When the amount of the crystal modifier is more than 100 mg/L, the surface of the ore layer may be mixed with a non-glossy surface in a non-uniform state (the plating coating property is deteriorated). Further, gold may become a disordered large particle, which may cause a mottled appearance or a peeling of the gold film due to excessive eutectoid precipitation of the crystal modifier. These can be the cause of poor joints. If the amount of the crystal modifier is less than 0.1 mg/L, plating coating properties, plating bath stability and durability may be deteriorated, or the plating bath may be decomposed. (4) Sulfite and sulfate (conductive salt) The sulfite or sulfate used as the conductive salt in the present invention may, for example, be a sulfite such as sodium sulfite, potassium sulfite, sodium metabisulfite or sodium hydrogen sulfite. Sulfate such as sodium sulfate. Among them, a combination of sodium sulfite and sodium sulphate is preferred. The blending amount of the above-mentioned sulfite and sulfate in the gold plating bath of the present invention is preferably within the range not impairing the object of the present invention, and preferably the following blending amount. The sulfite is preferably 5 to 100 g 10 to 80 g/L in terms of S?r2, and particularly preferably 20 to 60 g/L. If the sulfite is less than 5 g/L, the coating property and the liquid stability will be deteriorated, and plating may occur. If it exceeds 1 〇〇 g/L, the limit current will decrease and there will be burnt. The sulphate is usually determined to be 1 to 1 2 0 g / L, preferably g/L, and particularly preferably 1 to 40 g/L. If it is less than lg/L, the hardness of the film after heat treatment will be too high, causing the bump to be connected to the substrate, or the liquid stability may be deteriorated to cause decomposition of the plating bath. If g/L is used, the current density will be lowered to cause the lamination of the plating layer. (5) The buffering agent is used as a buffering agent in the present invention, and is not particularly limited as long as it is generally used by a gold-electric battery. For example, an inorganic acid salt such as a phosphate salt; an organic acid (carboxylic acid, hydroxycarboxylic acid) salt such as citric acid, phthalic acid or ethylenediamine may be used. In particular, the amount of the buffer in the non-cyanide gold plating bath of the present invention is 1 to 30 g/L, preferably 1 to 20 g/L, and 2 to 15 g/L. If the dosage of the best agent is less than 0.1 g/L, the pH will decrease and the liquid will be stable, and the plating bath component will be decomposed. If it exceeds 30 g/L, the current-limiting density is lowered, causing the plating to burn. Set, /L, to the amount of the bath, the decomposition of the raw layer, the formation of 1~60, the poor ί, 120: shape. In the plating bath, salt, boron acetate • 〇 usually set. The buffer will be deteriorated and there will be a boundary -11 - 200836278 (6) Palladium salt, platinum salt, zinc salt and silver salt as the palladium salt formulated in the non-cyanide gold plating bath of the present invention, and the tetraamine palladium chloride can be mentioned. Salt, tetraamine palladium sulfate, and the like. The platinum salt to be blended in the non-cyanide-based gold plating bath of the present invention may, for example, be a tetraamine platinum chloride or an ethylenediamine complex salt. As the zinc salt to be blended in the non-cyanide-based gold plating bath of the present invention, a zinc amine complex salt or the like can be mentioned. The silver salt to be blended in the non-cyanide-based gold plating bath of the present invention may, for example, be a silver thiosulfate salt. The palladium salt, the platinum salt, the zinc salt and the silver salt may be used singly or in combination of two or more kinds. The blending amount of the palladium salt, the platinum salt, the zinc salt and the silver salt in the non-cyanide-based gold plating bath of the present invention is determined by the total metal concentration of the metal salt of 0.1 to 200 mg/L, and 0.1 to 100 mg/L. Good, especially 0.1~25 mg/L. When gold plating such as bumps or wiring is performed on a germanium wafer or a compound wafer by electroplating using the non-cyanide gold plating bath of the present invention, the plating operation can be carried out in accordance with a usual method. For example, an A1 electrode is first formed by sputtering on the surface of an IC line formed on a wafer. Then, a Ti-W sputtering film or an Au sputtering film as an underlying metal film was sequentially formed. Then, masking is performed on the wafer with a masking agent. Then, gold plating is performed using the wafer as a substrate to be plated. Finally, the underlying metal film of the masking material, the portion not covered with gold bumps and the gold wiring is removed from the wafer. As a method of removing the masking material, a method of dissolving in a solvent and the like can be exemplified. As a method of removing the underlying metal film, a method of peeling off with a hydrogen peroxide solvent, a aqua regia solvent or the like can be exemplified. -12-200836278 In the masking agent, examples of the novolac-based positive-type resist include LA-900 and HA-900 which are commercially available products, and an acrylic negative-type photoresist, for example, BMR C-1 000 (above is Tokyo Chemical Industry Co., Ltd.) and so on. The temperature of the plating bath is usually 40 to 70 ° C, preferably 50 to 65 ° C. If the bath temperature is less than 40 °C, the precipitation will be uneven due to the decrease in current efficiency, and the film thickness and surface state of the electroless plating film may be uneven. Further, there is a case where the plating bath is decomposed due to a decrease in the conductivity of the plating bath. If the temperature of the plating bath exceeds 70 °C, the precipitated gold will grow into large particles to form a film, which may cause the surface of the plating film to become a matte surface, or the gold coordination salt may be decomposed due to the high temperature of the plating bath. The current density is usually 2.0 A/dm 2 or less at a gold concentration of 8 to 15 g/L and a plating bath temperature of 60 ° C, preferably 0.1 to 1.5 A/dm 2 and 0.3 to 0.8 A/dm 2 . Very good. If the current density exceeds the above range, a dendritic film may be deposited, or the metal ligand may be decomposed by application of a high voltage. If the current density is lower than the above range, productivity is lowered. Further, there is a case where the precipitated gold particles are coarsened and the surface of the ore layer is mat-like and is not suitable for bonding with the gold wiring. The pH of the non-cyanide-based gold plating bath of the present invention is usually 7.0 or more, and preferably 7.2 to 10.0. If the pH of the non-cyanide gold plating bath is less than 7.0, there will be a situation where the plating bath is quite unstable and the plating bath is decomposed. On the other hand, if the pH exceeds 10.0, there is a case where the masking agent dissolves to contaminate the plating film, or a gold bump of a desired shape cannot be formed due to the disappearance of the photoresist pattern. In the non-cyanide-based gold plating bath of the present invention, other components such as a P Η adjusting agent can be suitably used within the range not impaired by the present invention. -13- 200836278 The pH adjusting agent may, for example, be an acid such as dilute sulfuric acid water, sulfurous acid water or phosphoric acid, or a base such as sodium hydroxide, potassium hydroxide or ammonia water. In the non-cyanide-based gold plating bath of the present invention, it is possible to achieve two cycles by supplementing and managing the gold sulfite alkali salt as a gold source and other components in the mineral bath (in the case of all the gold in the plating bath) 1 cycle) use above. The object to be plated which can be plated by the non-cyanide-based gold plating bath of the present invention is not particularly limited as long as the material is metallized to impart conductivity. In particular, it is particularly suitable for, for example, forming bumps and wiring on a germanium wafer or a Ga/As wafer patterned using a novolac-based positive photoresist or an acrylic negative photoresist as a masking agent. Happening. [Examples] (Examples 1 to 6 and Comparative Examples 1 to 2) A non-cyanide gold plating bath of the formulation shown in Tables 1 to 2 was prepared. The unit of the concentration of each raw material is g/L unless otherwise specified. However, Na3Aii(S03)2 is a ruthenium wafer in which a 1C line is formed by using an Au amount, a Na2S〇3 system with a S03 amount, and a Na2So4 system with a S04 amount. The wafer has a bump opening patterned by a novolac-based positive photoresist. The cross-section of the substrate of the twin crystal is gold sputter/TiW sputter/passive film/A1 electrode/Si02·Si. A cross-sectional view thereof is shown in Fig. 2(A). In Fig. 2(A), 22 is a masking agent (photoresist), 24 is a gold sputter film, 25 is a TiW sputter film, 26 is a passivation film, 28 is a germanium wafer, and 30 is an A1 electrode. The object to be plated was immersed in 1 L of a prepared non-cyanide gold plating bath, and electroplated by -14-200836278 to form an electroplated film having a film thickness of 18 μm. Further, the current efficiency of the non-cyanide gold plating bath is usually 100% under a general plating operation. After forming a film with a predetermined film thickness, the masking agent is removed, the degree of the surface of the bump is formed, the bath stability, the appearance of the plating film, and the hardness of the film (untreated and 30 (TC, 30 minutes after heat treatment), and iodine) The etching property of the etchant was evaluated by the following method and standard. The results are shown in the table [degree of the difference in the surface of the bump film (μιη)] The contact of the passivation film shown in Fig. 2(A) is a touch The pin profiler (Profiler-P15, manufactured by KLA-TENKOR Co., Ltd.) was measured to obtain 1.5 μm. As shown in Fig. 2(B), the plating baths of Examples 1 to 6 and Comparative Examples 1 and 2 were used. Gold bumps 34. The masking material 22 (novolak-based positive photoresist) is then dissolved in a special solvent, methyl ethyl ketone. The maximum height 値 and the center of the edge of the gold bump 34 are measured by a stylus profiler. The difference b of the minimum height 部 of the part is used as the step difference (μπι) of the surface of the bump. The section of the characteristic required for the bump is usually 1 μηι or less. Further, the use of palladium-free, platinum salt, zinc salt and Any of the common baths of silver salt form gold bumps on the same object to be plated In the case, the post-plating step difference (μπι) of the bump surface is larger than the step difference (μηι) due to the passive film before electroplating [bath stability] After plating on the object to be plated, the condition of the plating bath is observed, according to -15- 200836278 Benchmark evaluation: Decomposition: plating solution decomposition X: The precipitation of gold in the plating bath can be observed with the naked eye. △: The precipitation of gold in the plating bath cannot be seen. Dialysis at 0·2 μπι The degree of precipitation was visually observed under a membrane filter of 1 000 mL. 〇: Gold precipitation could not be observed in the plating bath. [Electroplating appearance] The surface film of gold bumps formed on the shovel The appearance was visually observed and observed under an optical microscope, and evaluated according to the following criteria: X: The color tone was reddish, and the dendrite of the dendritic precipitation was observed, or the plating was burnt. Δ: No abnormal precipitation, and a glossy appearance. 〇: The hue is lemon yellow, and the uniform appearance of matt to semi-gloss [Film hardness (Vickers hardness; Hv)] The hardness of the film is measured by a Vickers hardness tester using a specific bump portion formed on the object to be plated ( Not heat treated After heat treatment at 300 °C for 30 minutes) Usually, the hardness required for the heat treatment of bumps is 60 Hv or less. The measurement conditions are based on the measurement of 25 gf for 10 seconds. Uniform etching property of Ail bump of etchant] -16- 200836278 The object to be plated is immersed in an iodine-based etchant which is sufficiently stirred at room temperature for 90 seconds, and then the alcohol-based rinse solution is washed and then sprayed with ethanol. After drying with a hair dryer, the surface state of all the bumps formed on the object to be plated was observed with an optical microscope at a magnification of 50 to 150, and the presence or absence of the mottle condition was evaluated in accordance with the following criteria. Here, "mottled" means a sleeve which is selectively dissolved in a portion which is selectively dissolved during etching and which is insoluble. X: Mottled condition can be observed on the surface of the bump above 50%. △: The mottled condition was observed only on the surface of the bump of the partial region. 〇: No mottled condition can be observed on all the bump surfaces of the object to be plated [Comprehensive evaluation] The evaluation results are evaluated based on the following evaluation criteria: X: Gold plating film (gold bump) and plating treatment The above evaluation results of the subsequent non-cyanide gold plating bath contained poor results. 〇: The above evaluation results of the formed gold plating film (gold bump) and the non-cyanide gold plating bath after the plating treatment were all good results. -17- 200836278 [Table 1] Real pay 1 2 3 4 5 6 Plating conditions Plating temperature (°c) 60 60 60 60 60 60 Current density (A/dm2) 0.5 0.5 0.5 0.4 0.6 0.5 Plating time (minutes) 58 58 58 58 58 58 Formulation concentration (g/L) Na3Au(S03)2WAii Meter 10 10 10 10 10 10 Na2So3 in S03 40 40 40 40 30 30 Na2So4 in S04 10 10 10 10 30 30 1,2-Diamine Ethylethane 4 4 4 4 15 15 Tl (mg/L) 15 15 15 15 15 15 Buffer A 15 15 15 15 - - Buffer B - - - - 5 5 Palladium salt (mg/L in Pd) 7 - - - 5 A platinum salt (mg/L in Pt) - 5 - - - 7 Zinc salt (mg/L in Ζιι) - - 15 - - - Silver salt (mg/L in Ag) • One • 10 _ Segment difference of the surface of the bump (μηι) 0.14 0.48 0.15 0.50 0.10 0.12 Stability of the plating bath 〇〇〇〇〇〇 plating film appearance 〇〇〇〇〇〇 film hardness not heat treated (Ην) 105 112 115 110 121 123 Hardness 30 (after TC heat treatment (Ην) 48 47 46 47 47 48 Comprehensive evaluation of etching properties 〇〇〇〇〇〇-18- 200836278 [Table 2]
比較例 1 2 電鍍條件 電鍍溫度(°c) 60 60 電流密度(A/dm2) 0.5 0.5 電鍍時間(分） 58 58 配方濃度(g/L) Na3Au(S03)2以 Au 計 10 10 Na2So3以 S03計 40 30 Na2S〇4以 S〇4i十 10 30 1，2-二胺基乙烷 4 15 Tl(mg/L) 15 15 緩衝劑A 15 - 緩衝劑B - 5 鈀鹽(mg/L以Pd計） - - 鉑鹽(mg/L以Pt計） - - 鋅鹽(mg/L以Zn計） - - 銀鹽(mg/L以Ag計） _ • 凸塊表面之段差(//m) 1.86 1.91 鍍浴安定性 〇 〇 電鍍皮膜外觀 〇 〇 皮膜硬度未熱處理(Hv) 103 96 皮膜硬度300°C熱處理後(Ην) 44 45 蝕刻性 〇 〇 綜合評價 X X 於表1〜2中，作爲緩衝劑A、緩衝劑B、鈀鹽、鉑鹽 、鋅鹽、銀鹽係使用下述者： 緩衝劑A :乙二胺四醋酸鉀 -19- 200836278 緩衝劑B :焦磷酸鉀 鈀鹽：四胺鈀二氯化物 鉑鹽：四胺鉑二氯化物 鋅鹽··硫酸鋅 銀鹽：硫代硫酸銀銨 【圖式簡單說明】 圖1爲表示形成於遮蔽材之開口部的金凸塊之一例的 半導體晶片之部分截面圖。 圖2爲遮蔽材經圖案化之半導體晶片的部分截面圖（A) ，與表示於金電鍍後將遮蔽材除去之半導體晶片的部分截 面圖（B)。 【主要元件符號說明】 2、2 8 ·晶圓 4、3 0 ： A1 電極 6、2 6 :鈍態膜 7 :開口部 8、 25 : TiW濺鍍膜 9、 24 :金濺鍍膜 1 〇 :金濺鍍膜之凸條 1 1 :凹部之底面 12、22 :遮蔽材 1 4、3 2 :遮蔽材之開口部 -20- 200836278 1 6、3 4 :金凸塊 1 8 :金屬球 20 :凹部 X :鈍態膜之段差Comparative Example 1 2 Plating conditions Plating temperature (°c) 60 60 Current density (A/dm2) 0.5 0.5 Plating time (minutes) 58 58 Formulation concentration (g/L) Na3Au(S03)2 in Au 10 10 Na2So3 to S03 40 30 Na2S〇4 to S〇4i 十 10 30 1,2-diaminoethane 4 15 Tl (mg/L) 15 15 buffer A 15 - buffer B - 5 palladium salt (mg / L to Pd -) Platinum salt (mg/L in Pt) - - Zinc salt (mg/L in terms of Zn) - - Silver salt (mg/L in terms of Ag) _ • Segment difference on the surface of the bump (//m) 1.86 1.91 plating bath stability 〇〇 plating film appearance 〇〇 film hardness is not heat treated (Hv) 103 96 film hardness 300 ° C heat treatment (Η ν) 44 45 etch 〇〇 comprehensive evaluation XX in Table 1-2, as a buffer The agent A, the buffer B, the palladium salt, the platinum salt, the zinc salt, and the silver salt are used as follows: Buffer A: Ethylenediamine tetraacetate potassium-19-200836278 Buffer B: potassium pyrophosphate palladium salt: tetraamine Palladium dichloride platinum salt: tetraamine platinum dichloride zinc salt · zinc sulfate silver salt: silver ammonium thiosulfate [simple description of the drawings] Fig. 1 is a view showing an example of gold bumps formed in the opening portion of the masking material of A partial sectional view of the semiconductor wafer. Fig. 2 is a partial cross-sectional view (A) of a patterned semiconductor wafer of a masking material, and a partial cross-sectional view (B) showing a semiconductor wafer from which a masking material is removed after gold plating. [Description of main component symbols] 2, 2 8 · Wafer 4, 3 0 : A1 Electrode 6, 2 6 : Passive film 7 : Openings 8, 25 : TiW sputter film 9, 24: Gold sputter film 1 〇: Gold Sputtered strip 1 1 : bottom surface 12, 22 of recessed portion: masking material 1 4, 3 2 : opening portion of masking material -20- 200836278 1 6 , 3 4 : gold bump 1 8 : metal ball 20 : recess X : the step of the passive film