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:
May. 06, 1986
Filed:
May. 13, 1985
John D Dreibelbis, Chalfont, PA (US);
I Marvin Weilerstein, Philadelphia, PA (US);
Kulicke and Soffa Industries Inc., Horsham, PA (US);
Abstract
Apparatus is provided for monitoring conditions of a fine wire interconnection during a bonding operation. The apparatus comprise a system which is capable of being installed on new automatic wire bonders or retrofitted into existing automatic wire bonders of the type which employ a main bonding processor for controlling the motion of the bonding tool. The semiconductor to be bonded is connected to a reference voltage and a variable frequency oscillator is magnetically or a.c. coupled to the fine wire above the bonding tool and below the wire feed. The bonding wire incurs changes in inductive and capacitive reactance during the bonding operation which cause variations in the frequency of the oscillator. A series of frequency samples are taken and recorded during a teaching operation in which good wire bond interconnections are made. The recorded frequency samples for each fine wire interconnection are compared to the frequency samples being taken during subsequent bonding operations and decisions are made at critical points of the bonding operation whether or not a good wire bond interconnection is being made without damaging the semiconductor device with excessive force or current.