TWI437650B - 半導體裝置連接用銅鉑合金細線 - Google Patents

半導體裝置連接用銅鉑合金細線 Download PDF

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TWI437650B
TWI437650B TW102116584A TW102116584A TWI437650B TW I437650 B TWI437650 B TW I437650B TW 102116584 A TW102116584 A TW 102116584A TW 102116584 A TW102116584 A TW 102116584A TW I437650 B TWI437650 B TW I437650B
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copper
wire
platinum
mass
bonding
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TW201411748A (zh
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Hiroyuki Amano
Michitaka Mikami
Junichi Okazaki
takuya Hamamoto
Shinichiro Nakashima
Tsutomu Yamashita
Syuichi Mitoma
Kosuke Ono
Bin Ryu
Hiroyuki SHIGYOU
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Tanaka Electronics Ind
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Description

半導體裝置連接用銅鉑合金細線

本發明係關於一種使用於以超音波並用熱壓著方式,連接半導體元件上的焊墊電極與外部電極之銅合金細線,且特別有關於一種在純度99.995質量%以上之銅(Cu)富含基體中,固溶少量鉑(Pt)之銅-鉑合金細線。

隨著近年來黃金價格高漲,以銅合金細線取代目前之4N黃金合金細線,再度受到注目。

適用於目前之銅合金細線之目前之超音波並用熱壓著接合方法,係使鋁焊墊上的銅合金接合線,保持在氮氣環境氣體或氫氣混入氮氣環境氣體等之非氧化性環境氣體,以電弧輸入熱加熱熔融接合線尖端,藉表面張力形成球後,在150~300℃之範圍內加熱過之半導體元件的電極上,以超硬工具自上方壓著接合線之球部,由其負荷及來自超硬工具之超音波震動之能量,接合銅合金細線與鋁焊墊者。

施加超音波之效果,係當用於助長銅合金細線之變形之接合面積擴大時,破壞及去除形成於銅鉑合金細線的表面之小於100奈米(nm)之表面氧化膜,藉此,使銅(Cu)等之金屬原子在下表面露出,在與相對接觸之打線焊墊之界面上產生塑性流動,一邊漸增彼此密著之新生表面,一邊原子間結合兩者。

又,適用於目前之銅合金細線之由超音波而得的楔打線方法,係使畫有回環之接合線,置於導線架上的導體配線之位置上,之後,以超硬工具自接合線上方,一邊使接合線壓抵在導線架上的導體配線,一邊在常溫施加超音波震動,以使接合線楔接合在導線架的導體上。接著,接合線被夾住,接 合線與超硬工具一齊上升以被切斷。

藉進行此等第1打線及第2打線,半導體元件與導線架被彼此連接。

雖然到目前為止,於銅(Cu)中固溶有鉑(Pt)等之貴金屬元素之銅富含合金細線有以下之物件,但是,無法控制銅(Cu)中之氧(O),所以,在銅合金細線表面產生氧化不均,而有無法進行第二次接合之問題。亦即,形成有濃淡之氧化膜,當氧化膜較濃時,即使施加超音波震動,氧化膜也不被分解,所以,必須加大接合面積以確保接合強度,當成為比20μm還要細之線徑時,有第二次接合強度不穩定之問題。

這樣的實例首先有日本特公平5-20493號公報(下述之專利文獻1)。其係使包含鎂(Mg)、鉿(Hf)等及鉑(Pt)之24個元素(將稀土類元素當作一個元素),在銅(Cu)中含有0.01~2重量%,藉此,其係「固定合金中之H、O、N、C,抑制氫氣、氧氣、氮氣及一氧化碳之產生(相同公報第2頁右上欄)」。但是,其並未開示控制銅富含合金細線的表面的氧化膜之技術。

又,有日本特開2008-085320號公報(下述之專利文獻2)。其係使鎂及磷之至少一種總計10~700質量ppm,使Ag、Pd、Pt及Au之至少一種總計10~5000質量ppm,使氧為6~30質量ppm含有在高純度銅為特徵之半導體裝置用銅合金接合線(相同公報之申請專利範圍第2項),其係欲控制接合線表面的氧化膜的氧,以改善球接合形狀及接合強度者。

此先前技術也與更早之先前技術同樣地,其係使包含在銅富含合金之氧(O)藉添加元素來控制者,完全未開示控制銅富含合金細線的表面的氧化膜之技術。

如上例所示,目前之銅合金接合線係調配既定之合金化成分,藉此,自銅(Cu)基體中欲排除非金屬成分之 氧(O)者。

結果,銅合金細線表面之氧化膜,一般以通常之化學性蝕刻或還原性環境氣體之高溫熱處理來去除。因此,當表面潔淨之銅合金細線表面在之後被熱處理,或者,被放置於大氣中時,形成種種氧化膜,銅合金細線表面的氧化膜不穩定之課題依然沒有被解決。

[先前技術文獻] [專利文獻]

[專利文獻1]日本特公平5-20493號公報

[專利文獻2]日本特開2008-085320號公報

本發明係提供一種使銅鉑合金細線表面之氧化膜,形成較薄且均勻的一定厚度,藉此,第二次接合性很優良,長期間之接合穩定性也很優良的銅鉑合金接合線,以及防止由球接合而得的第一次接合性中之晶片龜裂或鋁飛濺,提高斜靠性。

本發明人等發現當使銅鉑二元合金細線,自素線連續鑄造時,其成為在其極表面層中,析出銅(Cu)而鉑(Pt)濃度極低,之後,自表面往中心部逐漸增加的構造之傾向。而且,發現當使此極表面層中的銅(Cu)在大氣中氧化時,雖然立即形成一定厚度之氧化銅,但是,在銅鉑二元合金細線之內部存在鉑(Pt),藉此,氧化之進行被妨礙。如此形成的極表面層中之銅(Cu)的氧化膜,可藉鉑(Pt)之添加量以控制厚度,所以,可提供一種第二次接合性很優良的銅鉑合金接合線。

先前的銅接合線之製法,係與一般銅棒材或線材相同,其係自鑄塊鑄造而得的塊體或大直徑之連續鑄造材切出,藉伸線加工逐次縮小直徑,達到需要的μm等級之直徑。

在此種製造工序中,於鑄造後,表面之氧化層比較厚,其妨礙之後的伸線加工,所以,必須以切削或酸洗工序加以去除,與極表面層之銅層一齊被去除,而在線材之剖面方向中,不純物等之濃度係大概相同。

本發明人等發現的上述偏析,係在以直接連續鑄造製造直徑10mm以下的素線之過程中被觀察到者,其中,此素線藉酸洗過程等並未去除表面層,藉伸線加工過程,製成達到期望直徑之接合線,所以,在形成此等素線時之凝固過程中產生的偏析構造,係照原樣被維持。

因此,當此被鑄造的素線在凝固後,接觸到大氣環境氣體時,幾乎不含鉑(Pt)之極表面層的銅(Cu)被氧化,而形成氧化層,但是,如此形成的氧化層,係通過在鑄造後不久形成於素線上的氧化層,更經過伸線加工而被伸線成接合線之過程,對應伸線加工之加工度而變薄,即使如此,自外部進行氧化者之氧化領域,係停留在對應鉑(Pt)濃度之一定範圍,使氧化膜厚維持在均勻且相同的厚度。

此等之機構詳細雖然尚未明瞭,但是,其被考慮成當由自接合線素線之表面往內部測量的銅(Cu)與鉑(Pt)之濃度分佈檢討時,形成於接合線素線表面之銅(Cu)偏析層純度極高,所以,在最表層中,此高純度銅(Cu)形成與氧強力結合之均勻緻密且極薄的氧化層,此氧化層抑制氧往內部侵入,同時在其下方之銅(Cu)基體中,鉑(Pt)更抑制氧往內部侵入,直到經過之後的伸線加工而被加工到既定直徑之接合線,使氧化物層之厚度維持均勻且一定。

而且,在本發明中,銅鉑接合線為避免形成第一次接合之壓著球時太硬,檢討非金屬元素之氧(O)與硫(S)及磷(P)之添加量。

亦即,著眼於一直被當作銅(Cu)之不純物而被排斥的硫(S),在熔融球形成時,避免硫(S)析出在銅(Cu)球表面,所以,在鉑(Pt)金屬成分之外,再固溶非金屬成分之氧(O) 到銅(Cu)中,固定硫(S)在銅(Cu)基體中。結果,即使超音波並用熱壓著接合熔融球,在接合線之壓著球變形時,不產生加工硬化,動態強度也不變高。而且,藉調質熱處理,降低接合線之硬度,藉此,降低接合線之靜態強度。

又,在硫(S)、氧(O)及如有需要則加上磷(P)被抑制之濃度範圍,固溶到該基體中,藉此,控制由構成基體之鉑(Pt)及被固溶固定到此等基體中之添加元素而得的靜態強度及動態強度,同時提高接合線之韌性。

本發明之半導體裝置的接合線用銅鉑合金細線,係在由鉑(Pt)及剩餘部分為純度99.995質量%以上之銅(Cu)所構成的連續伸線過之半導體裝置用銅鉑二元合金細線中,該銅鉑合金細線之銅(Cu)基體中,固溶有做為金屬元素之鉑(Pt)0.1~2.0質量%,及做為非金屬元素之硫(S)1~10質量ppm與氧(O)10~150質量ppm,而且,6nm以下之均勻氧化膜覆蓋表層。

又,本發明之半導體裝置的接合線用銅鉑合金細線,係在由鉑(Pt)及剩餘部分為純度99.995質量%以上之銅(Cu)所構成的連續伸線過之半導體裝置用銅鉑二元合金細線中,該銅鉑合金細線之銅(Cu)基體中,固溶有做為金屬元素之鉑(Pt)0.1~2.0質量%與磷(P)1~5質量ppm,及做為非金屬元素之硫(S)1~10質量ppm與氧(O)10~150質量ppm,而且,6nm以下之均勻氧化膜覆蓋表層。

目前已知鉑(Pt)即使少量含有,也可防止銅(Cu)之氧化之性質。但是,已知在銅鉑二元合金細線凝固時,銅(Cu)析出在表層,純度愈高則此傾向愈明顯。在此,於本發明中,當利用此等性質而對連續鑄造後之鑄造品,一邊保持在高溫狀態一邊進行大氣冷卻時,在銅鉑二元合金細線之表面形成均勻的銅(Cu)薄膜。此銅(Cu)薄膜即使在之後進行中間熱處理,其膜厚也無變化。

又,在本發明中,鉑(Pt)係限制氧(O)及銅 (Cu)基體中之硫(S)之舉動。使鉑(Pt)之範圍限制在鉑(Pt)0.1~2.0質量%之原因在於:其未滿0.1質量%時,無法防止銅(Cu)之氧化進行,當其超過2.0質量%時,動態強度太高,而產生鋁飛濺及晶片龜裂。

此等鉑(Pt)之濃度範圍,如下所述,係對應圖3所示的氧化膜之厚度為6nm~2nm。

為穩定本發明之接合線之接合特性,鉑(Pt)宜為0.1~0.8質量%範圍,0.1~0.3質量%範圍則較宜。

在本發明中,使硫(S)添加1~10質量ppm之原因在於:使其具有接合線之韌性。當硫(S)未滿1質量ppm時,無法使其具有韌性,當其超過10質量ppm時,在球接合時,硫(S)係表面偏析而產生晶片龜裂。

又,硫(S)在熔融球接合時之接合線變形中,發現動態再結晶,即使接合線塑性變形,加工硬化也比較小,所以,與不含硫(S)之接合線相比較下,其晶片龜裂比較少。又,在本發明中,使氧(O)添加10~150質量ppm之原因在於:用於限制鉑(Pt)及銅(Cu)基體中之硫(S)之舉動。當氧(O)未滿10質量ppm時,無法具有此效果,當氧(O)超過150質量ppm時,在熔融球形成時,於球表面很容易形成氧化膜。為確實限制硫(S)之舉動,以氧(O)之含量較硫(S)之含量亦多為宜。

而且,在本發明中,宜為在銅(Cu)基體中,固溶有磷(P)1~5質量ppm。當銅(Cu)基體中具有磷(P)1~5質量ppm時,可限制氧(O)之移動,增加接合線之韌性。當磷(P)未滿1質量ppm時,其無此效果,當磷(P)超過5質量ppm時,硫(S)與氧(O)之平衡會崩潰。

本發明中之純度99.995質量%以上之銅(Cu)中之不純元素,可例舉銀(Ag)、鐵(Fe)、鎳(Ni)、鉛(Pb)、錫(Sn)、銻(Sb)、砷(As)、鉍(Bi)及鉻(Cr)等。

為發現銅(Cu)基體之動態強度及韌性,宜為銅(Cu)之 純度係99.998質量%以上。

在本發明中,連續伸線後之被調質熱處理過得銅鉑合金細線之維氏硬度,宜為77~105Hv。因為鉑(Pt)之添加量比較多,所以,當維氏硬度較高時,連續伸線後的銅鉑合金細線之靜態強度及動態強度變高,很容易產生鋁飛濺及晶片龜裂。其維氏硬度係75~85 Hv則較宜。

調質熱處理溫度雖然可依據銅鉑合金細線之成分組成而適宜選擇,但是,一般係在非氧化性環境氣體中,於300℃~500℃進行數秒鐘以下。在調質熱處理前,接合線於冷間被連續伸線加工,所以,藉調質熱處理,可產生應變被緩和的細微再結晶之銅(Cu)基體組織。依據連續伸線加工之剖面減少率(伸線加工前之線徑與伸線加工後之線徑之比),調質熱處理之溫度被決定。而且,可以在被連續伸線過之銅鉑合金細線,於施加一定張力之狀態下進行調質熱處理,以去除伸線應變。

此連續伸線宜為相對於連續伸線前之線徑而言,被冷間加工90%以上者。因為使接合線自鑄造組織轉變為伸線組織。被冷間加工99%以上則較宜。連續伸線加工宜為模具伸線,鑽石模則更佳。藉此,可生成被同心配置且細長之細微再結晶組織。

在本發明中,無須連續伸線前之素線之中間熱處理。中間熱處理已知一般係在非氧化性環境氣體中,於400℃~800℃實施60~180分鐘,但是,在銅鉑合金粗線的表面臨時形成之銅(Cu)薄膜或氧化膜的厚度幾乎不變。

本發明之接合線係在銅(Cu)基體中,含有做為金屬元素之鉑(Pt)0.1~2.0質量%,所以,銅鉑合金細線之表面的氧化膜較薄,在第一次接合時,即使形成熔融球,因為氧化膜而熔融球也不變硬。

又,如上所述,在接合線之表面臨時形成的氧化膜之厚度 係均勻且穩定,所以,在第二次接合時,藉一定輸出的超音波接合,本發明之銅鉑合金接合線可穩定接合。

因為固定做為非金屬元素之硫(S)與氧(O),所以,可利用接合線之韌性以很好地描繪接合回環,連接後之接合強度也可長期間穩定。

又,本發明之接合線不添加較銅(Cu)亦容易氧化的元素,所以,可固定氧(O)在銅(Cu)基體中,在形成熔融球時,藉表面氧化而不產生晶片龜裂。而且,在熔融球變形時,硫(S)無表面偏析,所以,動態強度不變高,自塑性變形時之接合線施加在晶片上之單位負荷也不增大,可防止晶片龜裂。又,磷(P)係與氧(O)結合而發揮銅鉑合金細線之焊劑之作用。

[圖1]、[圖2]

縱座標‧‧‧相對二次離子強度(次數)

橫座標‧‧‧深度(μm)

[圖3]

縱座標‧‧‧氧化膜厚度(nm)

橫座標‧‧‧鉑濃度(%)

圖1係測量自實施例(No.3)之素線表面往內部之銅(Cu)及鉑(Pt)之濃度分佈之曲線圖。

圖2係測量自實施例(No.3)之素線表面往內部之氧濃度分佈之曲線圖。

圖3係表示鉑濃度與接合線表面的氧化膜厚之關係之曲線圖。

實施例1~30及比較例1~6,係熔融表1所示之成分組成之合金,連續鑄造以製作直徑5mm之銅合金粗線。

自實施例1之銅鉑合金粗線的表面,以SIMS之質量分析計分別測量鉑(Pt)及銅(Cu)(第1圖)、氧(O)之濃度。曲線圖之橫軸係自粗線表面之深度(μm),縱軸係此等之相對二次離子強度(對數)。

當依據圖1時,鉑(Pt)不存在於表層,相對二次離子強度直至50nm皆比固溶體之母材還要低。相對於此,銅(Cu)在表面附近,其純度極高。

當依據圖2時,氧(O)係自表層至50nm直線性減少,之後,幾乎不往中心方向進入。由圖面可知:氧化膜厚度係0.05μm(50nm)左右。

接著,中間熱處理此實施例3之銅鉑合金粗線。中間熱處理係在至500℃之範圍進行120分鐘,之後,在水中急冷。而且,當同樣地測量表層氧化膜之厚度時,幾乎不見變化。

又,關於伸線加工此等粗線以做成直徑17μm之接合線,測量鉑(Pt)濃度與氧化物層厚度之關係,係表示於第3圖。

自鉑(Pt)濃度為0時之氧化膜厚度10nm,隨著鉑(Pt)濃度增加而氧化膜厚度激烈減少,接著,曲線變緩和,同時在鉑濃度係1~2質量%之領域中,氧化膜厚度2nm,大概飽和。

如下所述,實用上之本發明之效果,係在氧化膜厚度6nm~2nm時發揮。

之後,在冷間連續伸線實施例與比較例之接合線,在400℃進行1秒鐘以下之調質熱處理,各做成直徑17μm之接合線。在測量調質熱處理後的接合線之維氏硬度時,使用維氏硬度計(AKASI公司製型號MVK-G3)。而且,維氏硬度之數值係使用拉伸率4%時之接合線之硬度。

(熱壓著並用超音波接合條件)

在銅合金細線的線徑係17μm,回環長度係5mm,回環高度係170μm。使用K&S公司製之MAGUZAMU型全自動接合器,球接合銅合金細線到晶片(厚度0.5mm)上的電鍍0.8μm鋁(Al)-0.5質量%銅(Cu)合金膜上。接合條件係在120kHz之頻率下,關於FAB製作條件、負載及超音波條件,在第一次接合係FAB直徑為接合線直徑之1.6倍,壓著球直徑係接合線直徑之兩倍,又,關於第二次接合係任意調整,使得可 獲得良好接合,關於全部樣品100個係在相同條件下,實施第一次接合及第二次接合。毛細管使用配合接合線尺寸之SPT公司製物件。

接著,對於此被接合之銅鉑合金細線,進行鋁飛濺實驗、斜靠實驗及第二次接合性實驗。

(鋁飛濺實驗)

使接合後之樣品自正上方使用光學顯微鏡(奧林帕司製測量顯微鏡,STM6),以20倍之倍率觀察接合處周邊之鋁焊墊是否熱變形而捲縮。此鋁飛濺實驗係成為以FAB製作壓著熔融球時之FAB硬度之指標。實施例及比較例之接合線各觀察100處,只要發生一個鋁飛濺則標記X,一個也沒發生則標記○。而且,實施例及比較例皆未觀察到晶片龜裂。

(斜靠實驗)

自連結第一接合與第二接合的接合處之直線之延長上,以光學顯微鏡(奧林帕司製測量顯微鏡,STM6)觀察100支接合線之回環頂點的傾斜,求出其標準差(σ)。標準差(σ)只偏移4μm以下者則判定斜靠優◎,標準差(σ)偏移超過4μm~8μm者判定斜靠良○,標準差(σ)偏移超過8μm者判定斜靠不良X。

(第二次接合性實驗)

在銅(Cu)板上電鍍鎳(Ni)10μm,在其上電鍍鈀(Pd)1μm,在其上本身觸媒電鍍金(Au)0.5μm,其當作接合線基板。使此接合線基板一邊在175℃加熱,一邊進行銅合金細線之楔接合及接合線之拉引測試。結果,藉第二次接合有無剝離,調查第二次接合之接合性。在此,◎標記稱做機械強度係6.0gf以上者,○標記稱做機械強度係5.2~6.0gf者,△標記稱做機械強度係4.5~5.2gf者,X標記稱做機械強度係4.5gf以下者。

關於實施例1~30及比較例1~6之各實驗結果表示於表1。而且,氧濃度係藉燃燒法(LECO製氧.氮分析裝置 TC-436AR)測量之值,其雖然係基體中之固溶氧+表面氧化膜的氧之數值,但是,氧化膜之厚度係數nm等級,其影響被認為很微小,實質上,基體中的固溶氧濃度不改變,所以,以下當作固溶氧濃度處理。

又,為當作參考,也附加維氏硬度。

在例舉實施例及比較例之表1中,當對比接合線之組成範圍、被覆層之有無及鋁飛濺、斜靠、第二次接合性之實驗結果時,其結果如下。比較例1係硫(S)濃度為0.06質量ppm,其成為未滿下限值。又,氧(O)濃度係170質量ppm,其超過上限值。因此,比較例1係接合線之硬度較低,斜靠性較差,另外,由加工硬化而得的硬度變高,而鋁飛濺較差。又,表層之氧分佈成為斑塊狀圖案,第二次接合性也較差。

比較例2係原材料銅(Cu)純度為99.991質量%, 其成為未滿下限值。又,未含有硫(S),氧(O)濃度超過上限值。因此,比較例2也接合線變得太硬,鋁飛濺不佳。又,第二次接合性因為鈀被覆而稍差。

比較例3係原材料銅(Cu)純度為99.992質量%,其與比較例2同樣地成為未滿下限值。又,鉑(Pt)濃度係2.2質量%,其超過上限值。因此,比較例3係接合線變得太硬,鋁飛濺不佳。

比較例4係鉑(Pt)濃度較低,硫(S)濃度係16質量%,其超過上限值。因此,比較例4即使接合線硬度較低,其顯現動態強度而變得太硬,鋁飛濺不佳。

比較例5係鉑(Pt)濃度為0.02質量%,其未滿下限值。又,硫(S)濃度也係0.08質量ppm,其皆成為未滿下限值。因此,比較例4係接合線變得太軟,斜靠性較差。

比較例6係原材料銅(Cu)純度為99.993質量%,其與比較例2及比較例3同樣地成為未滿下限值。又,氧(O)也較高,因此,比較例6係接合線變得太硬,鋁飛濺不佳。

相對於以上之比較例而言,滿足本發明之成分組成範圍之條件之實施例,皆獲得良好的鋁飛濺、斜靠性及第二次接合性之結果。

其範圍係鉑(Pt)濃度為0.1~2.0質量%、硫(S)濃度為1~10質量ppm、氧(O)濃度為10~150質量ppm,其中,雖然鉑(Pt)濃度增加,同時接合線之硬度變高,但是,即使接合線硬度超過100Hv(實施例1、5、8、15、17、20、26),鋁飛濺實驗結果很良好,球壓著時之伴隨塑性流動之動態強度不變高。

又,本發明之接合線雖然上述鉑(Pt)濃度在0.1~2.0質量%中,可發揮效果,但是,該接合線構造由第3圖之曲線圖觀之,係對應鉑(Pt)濃度而氧化膜之厚度係6nm~2nm。

相對於氧化膜之厚度而言之評估雖然未例舉在表1,但是,一般當超過6nm時,第二次接合性降低,又,下限值2nm如上所述,其相對於鉑(Pt)濃度而言為飽和,但是,當鉑(Pt)濃度超過2.0質量%時,如上所述,動態強度變得太高而產生晶片龜裂,所以其被限制。

而且,即使接合線硬度未滿80Hv(實施例10、11、14、23),斜靠性實驗結果及第二次接合性實驗結果皆良好,其發揮硫(S)及氧(O)一齊添加之效果。尤其,在此等濃度範圍中,於各中間值或如完成之成分平衡中,此等效果皆很良好。

而且,磷(P)之添加係與硫(S)與氧(O)一同強化此等效果,又,由金(Au)及鈀(Pd)所構成之被覆層而得的效果,也加在此等之上而發揮作用。

[產業上之利用可能性]

本發明係第一次接合性、第二次接合性及回環形成性與先前接合線相比較下,大幅提高,所以,可提高接合線之可靠性,同時使接合工序可用比先前者更低的成本進行,產業上之利用價值極大。

縱座標‧‧‧氧化膜厚度(nm)

橫座標‧‧‧鉑濃度(%)

Claims (6)

  1. 一種半導體裝置連接用銅鉑合金細線,係由鉑(Pt)及剩餘部分係純度99.995質量%以上之銅(Cu)所構成,且經予連續伸線過,其特徵在於:該銅鉑合金細線之銅(Cu)基體中,固溶有做為金屬元素之鉑(Pt)0.1~2.0質量%、以及做為非金屬元素之硫(S)1~10質量ppm及氧(O)10~150質量ppm,而且,6nm以下之氧化層被覆表層。
  2. 一種半導體裝置連接用銅鉑合金細線,係由鉑(Pt)及剩餘部分系純度99.995質量%以上之銅(Cu)所構成且經予連續伸線過,其特徵在於:該銅鉑合金細線之銅(Cu)基體中,固溶有做為金屬元素之鉑(Pt)0.1~2.0質量%及磷(P)1~5質量ppm、以及做為非金屬元素之硫(S)1~10質量ppm及氧(O)10~150質量ppm,而且,6nm以下之氧化層被覆表層。
  3. 依申請專利範圍第1項或第2項所述之半導體裝置連接用銅鉑合金細線,其中,前述銅鉑合金細線的剩餘部分銅(Cu)之純度係99.998質量%以上。
  4. 依申請專利範圍第1項或第2項所述之半導體裝置連接用銅鉑合金細線,其中,前述銅鉑合金細線之維氏硬度係77~105Hv。
  5. 依申請專利範圍第1項或第2項所述之半導體裝置連接用銅鉑合金細線,其中,前述氧(O)之含量比前述硫(S)之含量還要多。
  6. 依申請專利範圍第1項或第2項所述之半導體裝置連接 用銅鉑合金細線,其中,前述連續伸線係對於形成有氧化膜之連續伸線前的線徑,進行90%以上之冷間加工者。
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