Process for flip chip connecting a semiconductor chip

• US 5,284,796 A
• Filed: 09/02/1992
• Issued: 02/08/1994
• Est. Priority Date: 09/10/1991
• Status: Expired due to Term

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Nakanishi, Teru, Ochiai, Masayuki, Hashimoto, Kaoru, Karasawa, Kazuaki
• Primary Examiner(s): Chaudhuri, Olik
• Assistant Examiner(s): Graybill, David E.
• Application Number:
  US07/939,695
• Time in Patent Office: 524 Days
• Field of Search: 437/183, 437/209, 437/226, 228/180.2, 228/254
• US Class Current: 438/108
• CPC Class Codes: H01L 2224/10135 Alignment aids
• CPC Class Codes: H01L 2224/1134 Stud bumping, i.e. using a wire-bonding apparatus
• CPC Class Codes: H01L 2224/13099 Material
• CPC Class Codes: H01L 2224/131 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 2224/13124 Aluminium [Al] as principal constituent
• CPC Class Codes: H01L 2224/13144 Gold [Au] as principal constituent
• CPC Class Codes: H01L 2224/45124 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48 of an individual wire connector
• CPC Class Codes: H01L 2224/81001 involving a temporary auxiliary member not forming part of the bonding apparatus
• CPC Class Codes: H01L 2224/81136 involving guiding structures, e.g. spacers or supporting members
• CPC Class Codes: H01L 2224/81191 wherein the bump connectors are disposed only on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/81193 wherein the bump connectors are disposed on both the semiconductor or solid-state body and another item or body to be connected to the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/81801 Soldering or alloying
• 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 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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 2924/01013 Aluminum [Al]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01078 : Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• 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 2924/09701 : Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/12033 : Gunn diode
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 2924/19043 : being a resistor
• CPC Class Codes: H05K 3/303 : Surface mounted components, e.g. affixing before soldering, aligning means, spacing means H05K3/32 takes precedence
• CPC Class Codes: H05K 3/3431 : Leadless components

Abstract

A process for a flip chip connection of a semiconductor chip includes the steps of forming a plurality of stud bumps on the semiconductor chip, on which a plurality of solder bumps are formed, in the vicinity of the outer periphery thereof and on the outside of the solder bumps, providing a cut groove between a plurality of the solder bumps and the stud bumps, mating the solder bumps on the semiconductor chip and the corresponding solder bumps on the circuit board and heating for subsequent integration of the mating solder bumps, and breaking way the outer peripheral portion of the semiconductor chip along the cutting groove after a flip chip connection in order to remove the stud bumps.

Claims

1. A process for flip chip connection of a semiconductor chip, in which solder bumps formed on the semiconductor chip in a matrix, arrangement are mated with a solder bumps formed on corresponding circuit board for flip chip connection, the process of said flip chip connection comprising the steps of:

forming a plurality of stud bumps on the semiconductor chip, on which a plurality of solder bumps are formed in the vicinity of the outer periphery thereof and the outer side of said solder bumps;

providing a cutting groove between a plurality of said solder bumps and said stud bumps;

mating the solder bumps on said semiconductor chip and the corresponding solder bumps on said circuit board and heating for integration of the mating solder bumps; and

breaking away the outer peripheral portion of said semiconductor chip along said cutting groove after a flip chip connection in order to remove said stud bumps.

2. A process as set forth in claim 1, wherein said step of forming said stud bumps is performed by wire bonding a wire on a pad one time or a plurality of times in a repeated manner and by subsequently crushing the bonded wire to a desired height.

3. A process as set forth in claim 1, wherein each of said stud bumps is formed with a height higher than the height of the individual solder bumps but shorter than the total height of the mating solder bumps.

4. A process as set forth in claim 3, wherein the height of each of said stud bumps is selected so as to form a smaller diameter waist portion at an intermediate portion of the integrated solder bumps.

5. A flip chip connection method as set forth in claim 1, wherein said step of forming each said stud bump is performed by wire bonding and cutting a wire to a predetermined cut length and then crushing said predetermined cut length of wire into a length corresponding to the desired height of said stud bump and forming a tip end plane surface.

6. A process as set forth in claim 5, wherein the step of wire bonding and cutting is performed by initially cutting the wire to a length shorter than said predetermined cut length, and sequentially repeating the step until the length of the cut wire attains said predetermined cut length.