Process for manufacturing electronic circuits

• US 6,161,748 A
• Filed: 03/30/2000
• Issued: 12/19/2000
• Est. Priority Date: 05/19/1995
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Fukuda, Hiroshi, Kazui, Shinichi, Katayama, Kaoru, Iwata, Yasuhiro, Ohta, Toshihiko, Shirai, Mitsugu, Tamura, Mitsunori
• Primary Examiner(s): Ryan, Patrick
• Assistant Examiner(s): STONER, KILEY SHAWN
• Application Number:
  US09/538,515
• Time in Patent Office: 264 Days
• Field of Search: 228/8, 228/9, 228/10, 228/6.2, 228/33, 228/36
• US Class Current: 228/8
• CPC Class Codes: H01L 2224/1181 Cleaning, e.g. oxide removal step, desmearing
• CPC Class Codes: H01L 2224/13111 Tin [Sn] as principal constituent
• CPC Class Codes: H01L 2224/16 of an individual bump connector
• CPC Class Codes: H01L 2224/45014 Ribbon connectors, e.g. rectangular cross-section
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/75 Apparatus for connecting with bump connectors or layer connectors
• CPC Class Codes: H01L 2224/7501 Means for cleaning, e.g. brushes, for hydro blasting, for ultrasonic cleaning, for dry ice blasting, using gas-flow, by etching, by applying flux or plasma
• CPC Class Codes: H01L 2224/81014 Thermal cleaning, e.g. decomposition, sublimation
• CPC Class Codes: H01L 2224/81022 Cleaning the bonding area, e.g. oxide removal step, desmearing
• CPC Class Codes: H01L 2224/81801 Soldering or alloying
• CPC Class Codes: H01L 24/75 Apparatus for connecting with bump connectors or layer connectors
• 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 2924/00014 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 2924/01019 Potassium [K]
• CPC Class Codes: H01L 2924/01024 Chromium [Cr]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/0105 : Tin [Sn]
• CPC Class Codes: H01L 2924/01075 : Rhenium [Re]
• CPC Class Codes: H01L 2924/01078 : Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/09701 : Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/12042 : LASER
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/15787 : Ceramics, e.g. crystalline carbides, nitrides or oxides
• CPC Class Codes: H01L 2924/16152 : Cap comprising a cavity for hosting the device, e.g. U-shaped cap
• CPC Class Codes: H01L 2924/166 : Material
• CPC Class Codes: H01L 2924/206 : Length ranges
• CPC Class Codes: H05K 3/3457 : Solder materials or compositions; Methods of application thereof
• CPC Class Codes: H05K 3/3489 : Composition of fluxes; Methods of application thereof; Other methods of activating the contact surfaces
• CPC Class Codes: Y10T 29/4913 : Assembling to base an electrical component, e.g., capacitor, etc.
• CPC Class Codes: Y10T 29/49144 : by metal fusion
• CPC Class Codes: Y10T 29/49155 : Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/49156 : with selective destruction of conductive paths
• CPC Class Codes: Y10T 29/49174 : Assembling terminal to elongated conductor

Abstract

The process for manufacturing an electronic circuit includes disposing an electronic device on a circuit substrate and hot melting a solder formed on the electronic device or the circuit substrate to bond the electronic device and the circuit substrate. The process includes the steps of feeding a liquid onto lands on the circuit substrate, aligning and mounting the electronic device on the lands, placing the circuit substrate in a treating vessel and heating the circuit substrate. The heating step includes controlling a pressure of an atmosphere in the treating vessel, hot-melting the solder to prevent at least a portion of the liquid from evaporating until the electronic device and the circuit substrate are bonded and to permit the liquid to evaporate after the electronic device and the circuit substrate are bonded.

Claims

1. An apparatus for manufacturing an electronic circuit substrate by hot-melting bump terminals of a solder material formed on an electronic device to connect surfaces of the electronic device and of a circuit substrate to each other, said apparatus comprising a treating vessel adapted to receive therein said electronic circuit substrate, pressure control means for controlling a pressure in said treating vessel, heating means provided in said treating vessel, transfer means for transferring into said treating vessel the electronic circuit substrate, in which said electronic device is temnorarily fixed on said circuit substrate by means of an alcoholic solution supplied in a manner to cover the connecting surface of said circuit substrate and the solder terminals on said electronic device, and apparatus control means for controlling an evaporation rate of said alcoholic solution for solder bonding by permitting said heating means to heat said electronic circuit substrate transferred into said treating vessel by said transfer means and permitting said pressure control means to control a pressure in said treating vessel.

2. The apparatus according to claim 1, wherein said pressure control means comprises evacuation means and gas introducing means, and can create an atmosphere containing a predetermined low concentration of oxygen within said treating vessel.

3. The apparatus according to claim 1, wherein said apparatus control means controls said heating means and said pressure control means in such a manner to inhibit evaporation of at least a part of said alcoholic solution until said solder material is subjected to hot-melting to connect said electronic device and said circuit substrate to each other, and to allow said alcoholic solution to evaporate after said electronic device and said circuit substrate are connected to each other.

4. The apparatus according to claim 3, wherein said apparatus control means causes said pressure control means to decrease a pressure in said treating vessel in order to evaporate said alcoholic solution after said electronic device and said circuit substrate are connected to each other.

5. The apparatus according to claim 3, wherein said alcoholic solution has a higher boiling point than a melting point of said solder material.