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TWI501366B - 封裝基板及其製法 - Google Patents

封裝基板及其製法 Download PDF

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Publication number
TWI501366B
TWI501366B TW100112523A TW100112523A TWI501366B TW I501366 B TWI501366 B TW I501366B TW 100112523 A TW100112523 A TW 100112523A TW 100112523 A TW100112523 A TW 100112523A TW I501366 B TWI501366 B TW I501366B
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Taiwan
Prior art keywords
electrical contact
contact pads
straight
type copper
contact pad
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TW100112523A
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English (en)
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TW201241981A (en
Inventor
Shih Ping Hsu
Tsung Yuan Chen
Ho Shing Lee
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Unimicron Technology Corp
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Priority to TW100112523A priority Critical patent/TWI501366B/zh
Publication of TW201241981A publication Critical patent/TW201241981A/zh
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Publication of TWI501366B publication Critical patent/TWI501366B/zh

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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/10Bump connectors; Manufacturing methods related thereto
    • H01L2224/15Structure, shape, material or disposition of the bump connectors after the connecting process
    • H01L2224/16Structure, shape, material or disposition of the bump connectors after the connecting process of an individual bump connector
    • H01L2224/161Disposition
    • H01L2224/16151Disposition the bump connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/16221Disposition the bump connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/16225Disposition the bump connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/26Layer connectors, e.g. plate connectors, solder or adhesive layers; Manufacturing methods related thereto
    • H01L2224/31Structure, shape, material or disposition of the layer connectors after the connecting process
    • H01L2224/32Structure, shape, material or disposition of the layer connectors after the connecting process of an individual layer connector
    • H01L2224/321Disposition
    • H01L2224/32151Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/32221Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/32225Disposition the layer connector connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42Wire connectors; Manufacturing methods related thereto
    • H01L2224/47Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/4805Shape
    • H01L2224/4809Loop shape
    • H01L2224/48091Arched
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42Wire connectors; Manufacturing methods related thereto
    • H01L2224/47Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/481Disposition
    • H01L2224/48151Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/48221Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/48225Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation
    • H01L2224/48227Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being non-metallic, e.g. insulating substrate with or without metallisation connecting the wire to a bond pad of the item
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/73Means for bonding being of different types provided for in two or more of groups H01L2224/10, H01L2224/18, H01L2224/26, H01L2224/34, H01L2224/42, H01L2224/50, H01L2224/63, H01L2224/71
    • H01L2224/732Location after the connecting process
    • H01L2224/73201Location after the connecting process on the same surface
    • H01L2224/73203Bump and layer connectors
    • H01L2224/73204Bump and layer connectors the bump connector being embedded into the layer connector
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/15Details of package parts other than the semiconductor or other solid state devices to be connected
    • H01L2924/151Die mounting substrate
    • H01L2924/153Connection portion
    • H01L2924/1531Connection portion the connection portion being formed only on the surface of the substrate opposite to the die mounting surface
    • H01L2924/15311Connection portion the connection portion being formed only on the surface of the substrate opposite to the die mounting surface being a ball array, e.g. BGA

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  • Electric Connection Of Electric Components To Printed Circuits (AREA)

Description

封裝基板及其製法
  本發明係有關一種封裝基板及其製法,尤指一種具直柱型銅凸塊之封裝基板及其製法。
  隨著電子產品的微型化發展趨勢,印刷電路板(PCB)表面可供設置半導體封裝結構的面積越來越小,因此遂發展出一種半導體封裝結構之立體堆疊技術,其係將複數個半導體封裝結構相互堆疊一起,而成為一層疊封裝件(package on package,簡稱POP),以符合小型表面接合面積與高密度元件設置之要求。
  請參閱第1圖,係習知之層疊封裝件之剖視圖,如圖所示,習知之層疊封裝件係將兩個具有晶片111,121的封裝結構11,12相互堆疊,並直接以焊球13連接,俾使該兩個封裝結構11,12之間有所間隔而不至於互相碰觸。
  惟,為了確保兩個封裝結構11,12之間不會互相碰觸,習知技術一般須使用較大直徑之焊球13以加深晶片封裝區域深度D,這使得焊球13的體積較大而佔用較大封裝基板表面積,進而不利於封裝基板面積的縮小;另外,在現代電子產品逐漸微型化之趨勢下,封裝基板上的焊墊112,122之間的間距也愈來愈小,因此於迴銲連接時,體積較大的焊球13也容易溢流至四周而造成橋接現象,進而導致不良品的產生。
  因此,如何避免習知技術中之層疊封裝件的焊球佔用過大的封裝基板面積,且容易在迴銲時造成橋接,而使得整體良率下降等問題,實已成為目前亟欲解決的課題。
  鑑於上述習知技術之種種缺失,本發明之主要目的係提供一種良率較高之封裝基板及其製法。
  為達上述及其他目的,本發明揭露一種封裝基板,係包括:線路板,係具有交互相疊之至少一介電層與線路層,且具有相對之第一表面及第二表面;複數第一電性接觸墊,係設於該第一表面上;複數第二電性接觸墊,係設於該第一表面上,其中,該等第一電性接觸墊係圍繞該等第二電性接觸墊,且該第一電性接觸墊之寬度係大於該第二電性接觸墊之寬度;以及直柱型銅凸塊,係設於各該第一電性接觸墊上,且該直柱型銅凸塊與該第一電性接觸墊之間係具有一導電層,其中,該直柱型銅凸塊之寬度係小於該第一電性接觸墊之寬度,且該直柱型銅凸塊係高於該第二電性接觸墊,以供該直柱型銅凸塊藉由焊料連接至其他基板,同時,該第一表面、第一電性接觸墊、第二電性接觸墊、與直柱型銅凸塊表面係外露於環境中。
  前述之封裝基板中,該第二表面復可具有複數第三電性接觸墊。
  依上述之封裝基板,該導電層22之材料係可選自由電鍍鎳/金、化學鍍鎳/金、化鎳浸金(ENIG)、化鎳鈀浸金(ENEPIG)及化學鍍錫(Immersion Tin)所組成之群組中之其中一者。
本發明復提供一種封裝基板之製法,係包括:提供一線路板,係具有交互相疊之至少一介電層與線路層,且具有相對之第一表面及第二表面,該第一表面上設有複數第一電性接觸墊及複數第二電性接觸墊,其中,該等第一電性接觸墊係圍繞該等第二電性接觸墊,且該第一電性接觸墊之寬度係大於該第二電性接觸墊之寬度;於該第一表面、該第一電性接觸墊及第二電性接觸墊上形成第一阻層,且該第一阻層具有複數第一開孔,以令各該第一電性接觸墊對應外露於各該第一開孔;於各該第一開孔外露之第一電性接觸墊上形成直柱型銅凸塊;以及移除該第一阻層,俾令該直柱型銅凸塊高於該第二電性接觸墊,該直柱型銅凸塊之寬度係小於該第一電性接觸墊之寬度,該直柱型銅凸塊係用以藉由焊料連接其他基板,且該第一表面、第一電性接觸墊、第二電性接觸墊、與直柱型銅凸塊表面係外露於環境中。
依上所述之封裝基板之製法,該第二表面復可具有複數第三電性接觸墊。
前述之封裝基板之製法中,形成該直柱型銅凸塊之步驟係可包括:於形成該第一阻層前,於該線路板之第一表面、該等第一電性接觸墊及第二電性接觸墊上形成導電層;於該導電層上形成該第一阻層,且該第一阻層中形成該等第一開孔;電鍍形成該直柱型銅凸塊;以及移除該第一阻層之步驟復包括移除該第一阻層所覆蓋之導電層。
由上可知,由於本發明之封裝基板用以連接其他封裝 結構的金屬凸塊係明顯高於置晶用電性接觸墊,所以能有效提高層疊封裝件(POP)對晶片的容許厚度,並避免相互堆疊之封裝結構有非預期的碰觸,且可使用較小直徑焊球,進而能改善後續封裝結構的可靠度。
以下藉由特定的具體實施例說明本發明之實施方式,熟悉此技藝之人士可由本說明書所揭示之內容輕易地瞭解本發明之其他優點及功效。
請參閱第2A至2F圖,係本發明之封裝基板及其製法的剖視圖。
如第2A圖所示,提供一線路板20,係具有交互相疊之至少一介電層(未以元件符號標示)與例如內層線路201的線路層,且具有相對之第一表面20a及第二表面20b,該第一表面20a上設有複數第一電性接觸墊211及複數第二電性接觸墊212,其中,該等第一電性接觸墊211係圍繞該等第二電性接觸墊212,且該第一電性接觸墊211之寬度係大於該第二電性接觸墊212之寬度,且該第二表面20b復具有複數第三電性接觸墊213。
如第2B圖所示,於該線路板20之第一表面20a、該等第一電性接觸墊211及第二電性接觸墊212上形成導電層22。
如第2C圖所示,於該導電層22上形成該第一阻層23a,且該第一阻層23a中形成有複數第一開孔230,以令各該第一電性接觸墊211對應外露於各該第一開孔230,並 於該第二表面20b與第三電性接觸墊213上形成該第二阻層23b。
如第2D圖所示,於各該第一開孔230外露之第一電性接觸墊211上形成直柱型銅凸塊24。
如第2E圖所示,移除該第二阻層23b、該第一阻層23a及其所覆蓋之導電層22,俾令該直柱型銅凸塊24高於該第二電性接觸墊212,該直柱型銅凸塊24之寬度係小於該第一電性接觸墊211之寬度,且該第一表面20a、第一電性接觸墊211、第二電性接觸墊212、與直柱型銅凸塊24表面係顯露於外。
本發明復提供一種封裝基板,係包括:線路板20,係具有交互相疊之至少一介電層與線路層,且具有相對之第一表面20a及第二表面20b;複數第一電性接觸墊211,係設於該第一表面20a上;複數第二電性接觸墊212,係設於該第一表面20a上,其中,該等第一電性接觸墊211係圍繞該等第二電性接觸墊212,且該第一電性接觸墊211之寬度係大於該第二電性接觸墊212之寬度;以及直柱型銅凸塊24,係設於各該第一電性接觸墊211上,且該直柱型銅凸塊24與該第一電性接觸墊211之間係具 有一導電層22,其中,該直柱型銅凸塊24之寬度係小於該第一電性接觸墊211之寬度,且該直柱型銅凸塊24係高於該第二電性接觸墊212,以供該直柱型銅凸塊24藉由焊料連接至其他基板,同時,該第一表面20a、第一電性接觸墊211、第二電性接觸墊212、與直柱型銅凸塊24表面係外露於環境中。
所述之封裝基板中,該第二表面20b復可具有複數第三電性接觸墊213。
於上述之封裝基板中,該導電層22之材料係可選自由電鍍鎳/金、化學鍍鎳/金、化鎳浸金(ENIG)、化鎳鈀浸金(ENEPIG)及化學鍍錫(Immersion Tin)所組成之群組中之其中一者。
綜上所述,相較於習知技術,由於本發明之封裝基板用以連接其他封裝結構的金屬凸塊(例如直柱型銅凸塊24)係明顯高於置晶用電性接觸墊(例如第二電性接觸墊212),所以能有效提高層疊封裝件(package on package,簡稱POP)對晶片的容許厚度,並避免相互堆疊之封裝結構有非預期的碰觸,且可使用較小直徑焊球,而能防止迴銲時的橋接,進而能改善後續封裝結構的可靠度。
上述實施例係用以例示性說明本發明之原理及其功效,而非用於限制本發明。任何熟習此項技藝之人士均可在不違背本發明之精神及範疇下,對上述實施例進行修改。因此本發明之權利保護範圍,應如後述之申請專 利範圍所列。
11、12‧‧‧封裝結構
111、121‧‧‧晶片
112、122‧‧‧焊墊
13、32‧‧‧焊球
D‧‧‧晶片封裝區域深度
20‧‧‧線路板
20a‧‧‧第一表面
20b‧‧‧第二表面
201‧‧‧內層線路
211‧‧‧第一電性接觸墊
212‧‧‧第二電性接觸墊
213‧‧‧第三電性接觸墊
22‧‧‧導電層
23a‧‧‧第一阻層
230‧‧‧第一開孔
23b‧‧‧第二阻層
24‧‧‧直柱型銅凸塊
26‧‧‧第一晶片
27‧‧‧封裝材料
3‧‧‧封裝結構
31‧‧‧第二晶片
第1圖係習知之層疊封裝件之剖視圖;以及第2A至2E圖係本發明之封裝基板及其製法的剖視圖。
20...線路板
20a...第一表面
20b...第二表面
201...內層線路
211...第一電性接觸墊
212...第二電性接觸墊
213...第三電性接觸墊
22...導電層
24...直柱型銅凸塊

Claims (6)

  1. 一種封裝基板,係包括:線路板,係具有交互相疊之至少一介電層與線路層,且具有相對之第一表面及第二表面;複數第一電性接觸墊,係設於該第一表面上;複數第二電性接觸墊,係設於該第一表面上,其中,該等第一電性接觸墊係圍繞該等第二電性接觸墊,且該第一電性接觸墊之寬度係大於該第二電性接觸墊之寬度;以及直柱型銅凸塊,係設於各該第一電性接觸墊上,且該直柱型銅凸塊與該第一電性接觸墊之間係具有一導電層,其中,該直柱型銅凸塊之寬度係小於該第一電性接觸墊之寬度,且該直柱型銅凸塊係高於該第二電性接觸墊,以供該直柱型銅凸塊藉由焊料連接至其他基板,同時,該第一表面、第一電性接觸墊、第二電性接觸墊、與直柱型銅凸塊表面係外露於環境中。
  2. 如申請專利範圍第1項所述之封裝基板,其中,該第二表面復具有複數第三電性接觸墊。
  3. 如申請專利範圍第1項所述之封裝基板,其中,該導電層之材料係選自由電鍍鎳/金、化學鍍鎳/金、化鎳浸金(ENIG)、化鎳鈀浸金(ENEPIG)及化學鍍錫(Immersion Tin)所組成之群組中之其中一者。
  4. 一種封裝基板之製法,係包括:提供一線路板,係具有交互相疊之至少一介電層與線路層,且具有相對之第一表面及第二表面,該第一表 面上設有複數第一電性接觸墊及複數第二電性接觸墊,其中,該等第一電性接觸墊係圍繞該等第二電性接觸墊,且該第一電性接觸墊之寬度係大於該第二電性接觸墊之寬度;於該第一表面、該第一電性接觸墊及第二電性接觸墊上形成第一阻層,且該第一阻層具有複數第一開孔,以令各該第一電性接觸墊對應外露於各該第一開孔;於各該第一開孔外露之第一電性接觸墊上形成直柱型銅凸塊;以及移除該第一阻層,俾令該直柱型銅凸塊高於該第二電性接觸墊,該直柱型銅凸塊之寬度係小於該第一電性接觸墊之寬度,該直柱型銅凸塊係用以藉由焊料連接其他基板,且該第一表面、第一電性接觸墊、第二電性接觸墊、與直柱型銅凸塊表面係顯露於外。
  5. 如申請專利範圍第4項所述之封裝基板之製法,其中,該第二表面復具有複數第三電性接觸墊。
  6. 如申請專利範圍第4項所述之封裝基板之製法,其中,形成該直柱型銅凸塊之步驟係包括:於形成該第一阻層前,於該線路板之第一表面、該等第一電性接觸墊及第二電性接觸墊上形成導電層;於該導電層上形成該第一阻層,且該第一阻層中形成該等第一開孔;電鍍形成該直柱型銅凸塊;以及移除該第一阻層之步驟復包括移除該第一阻層所覆蓋之導電層。
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CN108231729B (zh) * 2017-12-29 2020-07-14 通富微电子股份有限公司 一种封装基板、芯片封装体及芯片堆叠封装方法

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