TW380358B - Surface mount pad - Google Patents

Surface mount pad Download PDF

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Publication number
TW380358B
TW380358B TW086117324A TW86117324A TW380358B TW 380358 B TW380358 B TW 380358B TW 086117324 A TW086117324 A TW 086117324A TW 86117324 A TW86117324 A TW 86117324A TW 380358 B TW380358 B TW 380358B
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TW
Taiwan
Prior art keywords
contact
pad
circuit board
printed circuit
pads
Prior art date
Application number
TW086117324A
Other languages
English (en)
Inventor
Dimitry Grabbe
Original Assignee
Whitaker Corp
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Publication of TW380358B publication Critical patent/TW380358B/zh

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Classifications

    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00Apparatus or processes for manufacturing printed circuits
    • H05K3/40Forming printed elements for providing electric connections to or between printed circuits
    • H05K3/4007Surface contacts, e.g. bumps
    • H05K3/4015Surface contacts, e.g. bumps using auxiliary conductive elements, e.g. pieces of metal foil, metallic spheres
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00Apparatus or processes for manufacturing printed circuits
    • H05K3/30Assembling printed circuits with electric components, e.g. with resistor
    • H05K3/32Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits
    • H05K3/34Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits by soldering
    • H05K3/341Surface mounted components
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01RELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R12/00Structural associations of a plurality of mutually-insulated electrical connecting elements, specially adapted for printed circuits, e.g. printed circuit boards [PCB], flat or ribbon cables, or like generally planar structures, e.g. terminal strips, terminal blocks; Coupling devices specially adapted for printed circuits, flat or ribbon cables, or like generally planar structures; Terminals specially adapted for contact with, or insertion into, printed circuits, flat or ribbon cables, or like generally planar structures
    • H01R12/70Coupling devices
    • H01R12/71Coupling devices for rigid printing circuits or like structures
    • H01R12/712Coupling devices for rigid printing circuits or like structures co-operating with the surface of the printed circuit or with a coupling device exclusively provided on the surface of the printed circuit
    • H01R12/714Coupling devices for rigid printing circuits or like structures co-operating with the surface of the printed circuit or with a coupling device exclusively provided on the surface of the printed circuit with contacts abutting directly the printed circuit; Button contacts therefore provided on the printed circuit
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01RELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R13/00Details of coupling devices of the kinds covered by groups H01R12/70 or H01R24/00 - H01R33/00
    • H01R13/02Contact members
    • H01R13/22Contacts for co-operating by abutting
    • H01R13/24Contacts for co-operating by abutting resilient; resiliently-mounted
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2203/00Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
    • H05K2203/03Metal processing
    • H05K2203/033Punching metal foil, e.g. solder foil
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2203/00Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
    • H05K2203/03Metal processing
    • H05K2203/0338Transferring metal or conductive material other than a circuit pattern, e.g. bump, solder, printed component
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50Manufacturing or production processes characterised by the final manufactured product
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49002Electrical device making
    • Y10T29/49117Conductor or circuit manufacturing
    • Y10T29/49124On flat or curved insulated base, e.g., printed circuit, etc.
    • Y10T29/49147Assembling terminal to base
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49002Electrical device making
    • Y10T29/49117Conductor or circuit manufacturing
    • Y10T29/49124On flat or curved insulated base, e.g., printed circuit, etc.
    • Y10T29/49147Assembling terminal to base
    • Y10T29/49149Assembling terminal to base by metal fusion bonding

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Electric Connection Of Electric Components To Printed Circuits (AREA)
  • Structures For Mounting Electric Components On Printed Circuit Boards (AREA)

Description

86558 86558 經濟部中央標準局員工消費合作社印製 五、發明説明() 本發明係有關於將電子元件電連接至 及更詳而言之,尤指m安録印刷 安裝墊,以進行前述之電連,接。 板上之表面 雪針格陣聊他)、陸格_ (LGAs)、球格㈣ 、 5在電子工業中為眾所周知的電子封奘曰此心 …
RrA a .彳黾千封裝。目前的趨勢是使用 ^ LGA封裝。LGA封袭需要壓縮承座技術。該封裝 通吊在其安裝塾的表面設置有金子,這樣在封裝及印刷電 路板間僅需要很小的壓迫接觸力即可以獲致可#的電連 接。當印刷電路板完成製造時,典型地在穿孔(貫通孔)或 1〇表面安裝墊處施佈有焊料以便將元件安裝在其上。將電子 $裝以壓迫方式安裝在前述具焊料的安裝墊或穿孔上,射 ^要相當高的壓迫力量,才能在封裝與印刷電路板間建立 可靠的電連接。而要在封裝及具焊料的安裝墊間得到可靠 電連接,所需施加的接觸力則大約為15〇克,而在兩金表 1達到相同可靠的電遂接則僅.需要5〇克的力。因為電 子封裝的安裝墊都是鍍金的,那麼最好在印刷電路板的對 應的塾片上也提供一層金表面。但是,製造這樣的一塊印 刷電路板需要很複雜的製程,才能在印刷電路板的隔絕區 域鍍上一層金。 20 頌給格拉伯等人的美國專利第5,073,118號揭露出電 接點’其包括有一頭部,其上具有一扁平接觸墊結令面, 及形狀呈配合銷的踵部,該配合銷延伸穿過印刷電路板鍍 有焊料的穿孔(貫通孔),以容許像LGA這樣的電子封此 以壓迫性方式安裝在扁平接觸墊結合面上。該接觸墊結 -3 (讀先閱讀背面之注意事項再填寫本頁) 裝- .—1 - - - - -、ST.¾ I--- 8〇558 Β7 ' 五、發明説明() 面鍍有金手,因此降低了達到可靠電連接所需要的摩迫 力。但是這種..技術並未提供 > 種方法以將電子封裝連接至 不具備鍍有焊料之穿孔且是針對表面安裝式連接的印刷電 硌板上。因弗便存在一禮間題,即需要在電子封裝及專為 5 表面安裝連接設計之印刷電路板間建丘二種金-對-金的電 連接。 '' 本發明之目的在於提供一種在電子封裝及一印刷電路 板乏表面安裝墊片間建立可靠的壓迫式電連接之結構及方 法。-. ' 10 前述之目的可藉著提供一大致為平面具可以表面安裝 方式連择至印刷電路板之接觸墊來達成'^該接鵷墊具有一 安裝奉面I可焊接至印刷電路板之鍍有烊料之墊片上。在 該安裝表面相對侧具有一接觸結合面(接觸表面),該揍觸 表面鐘有一層如金或起金屬、之材料,該材料係與該電子封 15 裝之接觸墊電相容,於是僅需要施加相對小的壓迫力即可 在其間建立可靠的'電連接。· 本發明將配合附圖,以說明方式說明,其中: 圖1為拫據本發明接觸墊之皋體圖,該接觸墊在安裝 前係懸吊於印刷電路板上; 經濟部中央標準局員工消費合作社印製 (請先聞讀背面之注意事項再填寫本頁) 20 圖2為根據本發明接觸墊之立體圖,該等接觸墊在組 合至印刷電路板上前先黏性地結合至一薄膜上; 圖3為一横剖面圖,揭露出製造根據本發明結構之方 法; 圖4為圖2所示接觸墊及薄膜之横剖视圖; 本紙張尺度適用中國國家標準(CNS ) A4規格(210X297公釐) A7 86558 B7 五、發明説明() 10 15 經濟部中央標準局員工消費合作社印製 圖5係與圖3相似之橫剖面圖,其中接觸墊仍然安裝 在一薄膜上,及袜焊接至印刷電路板<墊片上;及 圖6為接觸墊在移除薄膜後之橫剖面圖。 .本發明將先參考圖1來說明,其中接觸墊2在組合前 係懸吊在印刷電路板4之上。該印刷電路4典型地製備有 線路8以與印刷電路滅Γ上的組件連接,及製備有墊片6係 由談等線路延伸以便與該組件連接。該墊月6塗佈有一層 焊料膏7,如圖4所示。圖中揭露的接觸墊2大致具有— 碟狀的平面型本體。該接觸墊2亦可以製做成其他形狀, 以配合墊片6的特殊形狀,該墊片6係設置在印刷電路板 4的上表面14 ^該接觸墊2具有一安裝表面12,在運用 表面安裝技術下可以安裝至印刷電路板4的墊片6上。位 在該安裝表面12相對侧的接觸表面則採用傳統的冶金 技術以在電子封裝(圖中未示)的墊片間構成可靠的電連 接。傳統使用的冶金技術的範例則為鎳阻隔層6,其上塗 有一層金層9,可以電鍍、濺鍍、焊接或軋合等技術加上 去’彼等在該工業中都是熟知的技術。該接觸墊2較佳的 禽相成分如下,第一層為在安裝表面12上的焊料7,然 後再一層鋼3,然後再一層鎳5,最後再一層位在接觸表 面10上的金9。 現在將配合圖2至圖5而詳細地說明將接觸塾組合至 印刷電路板上。先請參考圖2,一陣列的接觸墊2係黏至 一層薄膜20上’該薄膜材料為聚醯亞胺、多元酯或其他 任何材料,只要可承受焊料熔化的溫度即可。該薄膜2〇 (諳先鬩讀背面之注意事項再填寫本頁)
^Rt^n n mt —m »1- - - 丁 、T 各紙張尺度適用中國國家標準(CNS ) Α4規格(2丨0X297公釐) A7 86558 B7 ' , 五、發明説明() 在其接觸表面22上有一層黏膠16(見圖3),可暫時性地 將排成陣列的接觸墊2黏住在相對應於印刷電路板4上的 接觸墊6位置處,而接觸墊2即寸安裝在其上。該陣列之 形成方式如下,先將一銅片15根據前述之方式完成電鍍 5 作業。然後將每一接觸墊2由該完成電鍍之銅片15上沖 壓裁切而成,如圖3淆示。沖壓作業最好採用沖頭11, 該衝頭會由圖3所示之位置朝下移動及接觸到銅片15, 並將一接觸墊2經由模板13處衝出。朝下的沖壓行程的 結束點剛好將接觸墊2黏在薄膜20上。接觸墊2可利用 10 這種方式形成,其中.銅片持續地由一方向送入,或利用另 一相似的方法形成,其中銅片在兩個軸線上移動,以杳更 寬的銅片上沖壓陣列式孔洞。在另一種實施例中,也可以 採用製造印刷電路板的技術,以在薄膜20上創造出接觸 墊陣列。 15 圖4揭露出薄膜20及一接觸墊2的一部份,該薄膜 經濟部中央標準局員工消費合作社印製 (請先閱讀背面之注意事項再填寫本頁) 20已與接觸墊2結合及置於印刷電路板4的上方,使得 接觸墊2與印刷電路板4的墊片6對齊。因為接觸表面22 延伸超過接觸墊陣列的邊緣,因此可以用來定位及黏性地 將薄膜連接至印刷電路板4的頂表面14,以將接觸墊陣 20 列適當地定位以進行焊接作業。 現請參考圖5,將更詳細地揭露焊接作業。整個總成 係置錫爐(回焊爐)内,使得焊料7熔化流動以在接觸墊2 與印刷電路板4之墊片6間形成焊料連接。同時要注意的 是,在此步驟中該黏膠16被熔化而自薄膜20處分離。在 -6- 本紙張尺度適用中國國家標準(CNS > A4規格(210X297公釐)
8655S A7 B7 五、發明説明() 另一實施例中,亦可以採用耐高溫黏膠,因此在過錫爐步 騍中不會熔化。最後,薄膜20由接觸墊2處撕離(圖6), 而組合步驟亦完成了。具有電相容接觸表面10之接觸墊 2在安裝到印刷電路板4後,即可以壓迫方式在其上安裝 5 一電子封裝。 ' 本發明的優點在於提供一電相容接觸墊,以在電子封 裝及印刷電路板的墊片間建立一僅需低壓縮力即可達到的 可靠電連接。本發明的額外優點在於提供一種簡單的組合 方法,使得接觸墊不需複雜的局部'化電鍍作業即可連接至 10 印刷電路板上。 (請先聞讀背面之注意事項再填寫本頁) 經濟部中央標隼局員工消費合作社印製 -7- 83. 3.10,000 本紙張尺度適用中國國家標準(CNS ) A4規格(210X297公釐)

Claims (1)

  1. 經濟部中央標準局員工消費合作社印製 A8 g 86558 D8 , 六、申請專利範圍 1- 一種接觸墊,其具有一接觸表面以在電子封裝與印刷 電路板間構成電連接,該接觸塾之特徵在於: 一大致平坦且具有一安裝表面之本體,該安裝表面可 $表面焊接至印刷t路板之聲片上,該接觸表面鍍有一層 5 與該電子封裝磋觸墊材料電相容之材料,及在該電子封裝 及該印刷電板之墊片間II著在其間施,加壓力而建立可靠之 電連接。 2. 根據申請專利範.圍第1項之接觸塾5其中該接觸本體 •係由鋼所構成。 1〇 3. 根據申請專利範圍第?項之接觸墊,其中該接觸本體 之第一主要表面上鍍有一層鎳。 4. 根據申請專利範圍第3項之接觸墊,其中該接觸本體 之鎳層上鍍上一層金以形成接觸表面。 5. 根據申請專利範圍第1項之接觸墊,其中該接觸本體 15 進一步在其相對於該接觸表面之第二主要表面上包括一層 焊料,以形成一安裝表面。 6. 一種將大致為平面型之接觸墊陣列安裝至相對應印刷 電路板墊片陣列上之方法,該等接觸墊具有一接觸表面且 鍍有一層材料,該材料係與一電子封裝之接觸墊材料電相 20 容,該方法包括有碑下之步驟: 將多數接觸墊黏性地附著盖一薄膜上,使得該等接觸 墊構成一與該印刷電路板上附著之墊片陣列相對應之陣 列; 將焊料膏施佈至印刷電路板上之對應聲片陣列之每一 -8- 本紙張尺度適用争國國家標準(匸奶)八4^洛(210><297公釐) —.-------装------訂-----^—W (請先閎讀背面之注意事項再填寫本頁) gg 86558 C8 - D8 六、申請專利範圍 對應墊片之榦露表面上; 將具有該接觸墊陣列之薄膜置於該印刷電路板上,使 得每一陣列中之接觸墊與該印刷電錶板上相對應墊片之裸 露表面接合; 5 重新使該焯料膏流動;及 將該薄膜由該接辑墊上移除。 7. 根據申讀專利範圍第6項之方法,進一步包括延屐該 薄m超過該接觸墊陣列區域,及施佈一接觸.黏膠至該處之 一主要表面之步驟。’ ίο δ. 根據申請專利範圍第7項之方法,其中每一接觸墊係 在每一單次沖壓行程中,由一片鍍層材料片上沖壓裁切, 且黏性地釁放至該薄膜上而形成。 (請先閎讀背面之注意事項再填寫本頁) 經濟部中央標準局員工消費合作社印製 本紙張尺度適用中國國家標隼(CNS ) Α4規格(210X297公釐)
TW086117324A 1996-12-10 1997-11-20 Surface mount pad TW380358B (en)

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US76306096A 1996-12-10 1996-12-10

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TW380358B true TW380358B (en) 2000-01-21

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US (1) US6012225A (zh)
AU (1) AU5597398A (zh)
TW (1) TW380358B (zh)
WO (1) WO1998026637A1 (zh)

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