The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 30, 1994
Filed:
May. 29, 1992
Toru Nishikawa, Fujisawa, JP;
Ryohei Satoh, Yokohama, JP;
Masahide Harada, Fujisawa, JP;
Tetsuya Hayashida, Tokyo, JP;
Mitugu Shirai, Hatano, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a method of soldering for use in fabricating electronic circuit device, after an oxide layer and/or contaminated layer on a surface of a soldering material and members to be soldered thereby is removed by sputter-cleaning with atom or ion, the members are aligned in an oxidizing atmosphere within a predetermined time period and, then, the soldering material is heated in non-oxidizing atmosphere to performe soldering. An apparatus for performing the above method comprises a sputter cleaning device, an alignment device operable in atmospheric condition and a heating and soldering device in the form of a belt furnace operable in non-oxidizing or reducing environment. Instead of the sputter cleaning device, a mechanical polishing or cutting device can be used to cleaning a surface of solder or a member to be bonded or a solder ball plated with gold may be used. An alignment between two members to be bonded is provided by an alignment mark means which comprises a protrusion on a surface of one member and a complimental recess formed at a center portion of a protrusion means formed on a corresponding surface of the other member.