Integrated electronic device having flip-chip connection with circuit board and fabrication method thereof

• US 20040209453A1
• Filed: 05/18/2004
• Published: 10/21/2004
• Est. Priority Date: 07/20/1994
• Status: Abandoned Application

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Shimizu, Kozo, Nakanishi, Teru, Akamatsu, Toshiya, Karasawa, Kazuaki
• Application Number:
  US10/847,614
• Publication Number:
  US 20040209453A1
• Time in Patent Office: Days
• US Class Current: 438/613
• CPC Class Codes: B23K 35/26 with the principal constituent melting at less than 400 degrees C
• CPC Class Codes: H01L 2224/05624 Aluminium [Al] as principal constituent
• CPC Class Codes: H01L 2224/05639 Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/05644 Gold [Au] as principal constituent
• CPC Class Codes: H01L 2224/05655 Nickel [Ni] as principal constituent
• CPC Class Codes: H01L 2224/1147 using a lift-off mask
• CPC Class Codes: H01L 2224/13099 Material
• CPC Class Codes: H01L 2224/13109 Indium [In] as principal constituent
• CPC Class Codes: H01L 2224/13111 Tin [Sn] as principal constituent
• CPC Class Codes: H01L 2224/13201 the principal constituent melting at a temperature of less than 400°C
• CPC Class Codes: H01L 2224/13211 Tin [Sn] as principal constituent
• CPC Class Codes: H01L 2224/133 with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• CPC Class Codes: H01L 2224/16506 comprising an eutectic alloy
• CPC Class Codes: H01L 2224/29099 Material
• CPC Class Codes: H01L 2224/81097 Heating
• CPC Class Codes: H01L 2224/81191 wherein the bump connectors are disposed only on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/81192 wherein the bump connectors are disposed only on another item or body to be connected to the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/81201 Compression bonding
• CPC Class Codes: H01L 2224/81805 involving forming a eutectic alloy at the bonding interface
• CPC Class Codes: H01L 2224/81825 Solid-liquid interdiffusion
• CPC Class Codes: H01L 24/05 : of an individual bonding area
• CPC Class Codes: H01L 24/13 : of an individual bump connector
• CPC Class Codes: H01L 24/16 : of an individual bump connector
• CPC Class Codes: H01L 24/81 : using a bump connector
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00013 : Fully indexed content
• CPC Class Codes: H01L 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01004 : Beryllium [Be]
• CPC Class Codes: H01L 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01015 : Phosphorus [P]
• CPC Class Codes: H01L 2924/01022 : Titanium [Ti]
• CPC Class Codes: H01L 2924/01024 : Chromium [Cr]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/0103 : Zinc [Zn]
• CPC Class Codes: H01L 2924/01031 : Gallium [Ga]
• CPC Class Codes: H01L 2924/01032 : Germanium [Ge]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/01049 : Indium [In]
• CPC Class Codes: H01L 2924/0105 : Tin [Sn]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/01083 : Bismuth [Bi]
• CPC Class Codes: H01L 2924/01322 : Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/351 : Thermal stress
• CPC Class Codes: H05K 3/3436 : having an array of bottom contacts, e.g. pad grid array or ball grid array components
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product

Abstract

An integrated electronic device having an electric connection between a first electrode of a semiconductor chip and a second electrode of a circuit board. One embodiment according to the present invention is a method for fabricating an integrated electronic device having an electric connection between a first electrode of a semiconductor chip and a second electrode of a circuit board, both surfaces of the first and second electrodes having an adhesive tendency to molten metal, the method comprising the steps of forming a metal bump on the first electrode, the metal bump being made of a soldering metal alloy consisting of a solid phase component and a liquid phase component at an operating temperature; and forming an electric connection between the first electrode and the second electrode by heating the soldering metal alloy so as to adhere to the surface of the second electrode.

Claims

1. A method for fabricating an integrated electronic device having an electric connection connecting a first electrode of a first substrate with a second electrode of a second substrate, surfaces of the first and second electrodes having repellant and adhesive tendencies to molten metal, respectively, the method comprising the steps of:

forming a first soldering metal bump on the surface of the first electrode, the first soldering metal bump including at least one of components of an eutectic alloy having an eutectic temperature, wherein the first soldering metal bump has a first melting temperature;

forming a second soldering metal bump on the surface of the second electrode, the second soldering metal bump including the rest of the components of the eutectic alloy, wherein the second soldering metal bump has a second melting temperature;

aligning the first and second soldering metal bumps to each other, and then keeping both in contact with each other; and

heating the first and second soldering metal bumps at such a connection temperature that a connection part made of the eutectic alloy is formed between the first and second soldering metal bumps,

wherein the connection temperature is higher than the eutectic temperature and lower than the melting temperatures of the first and second soldering metal bumps.

2. A method for fabricating an integrated electronic device according to claim 1, wherein the eutectic temperature of the eutectic alloy is higher than a highest limit of an operating temperature of the integrated electronic device.

3. A method for fabricating an integrated electronic device according to claim 1, wherein one of the first and second soldering metal bumps is made of at least a component of a binary alloy of In—

Bi, a tertiary alloy of Sn—

Bi—

In or a four-element alloy of Sn—

Pb—

Bi—

In, and the other of the first and second soldering metal bumps is made of the rest of the components of the binary alloy, the tertiary alloy or the four element alloy.

4. A method for fabricating an integrated electronic device according to claim 1, wherein one of the first and second soldering metal bumps is made of at least a component of a binary alloy of Cd—

Bi, a tertiary alloy of Sn—

Bi—

Cd or a four element alloy of Sn—

Pb—

Bi—

Cd, and the other of the first and second soldering metal bumps is made of the rest of the components of the binary alloy, the tertiary alloy or the four element alloy.

5. A method for fabricating an integrated electronic device according to claim 1, wherein the electric connection is composed of Ge as an additional minor component.

6. A method for fabricating an integrated electronic device according to claim 1, wherein the first substrate is a semiconductor chip and the second substrate is a circuit board.

7. A method for fabricating an integrated electronic device according to claim 5, wherein the first substrate is a semiconductor chip and the second substrate is a circuit board.

8. A method for fabricating an integrated electronic device having an electric connection connecting a first electrode of a first substrate with a second electrode of a second substrate, both surfaces of the first and second electrodes having an adhesive tendency to molten metal, the method comprising the steps of:

forming a soldering metal bump on the surface of the first electrode, the soldering metal bump essentially consisting of components of an eutectic alloy having an eutectic temperature, wherein the soldering metal bump has a melting temperature higher than the eutectic temperature;

mounting the first substrate on the second substrate such that the soldering metal bump is aligned to the corresponding second electrode; and

melting the soldering metal bump at the melting temperature, and then solidifying the soldering metal bump into the electric connection connecting the first electrode with the second electrode.

9. A method for fabricating an integrated electronic device according to claim 8, wherein the eutectic temperature of the eutectic alloy is in the operating temperature range of the integrated electronic device.