Method and apparatus for the production and quality testing of a bonded wire connection
AssigneeF & K Delvotec Bondtechnik GmbH
InventorFarhad Farassat
Life of this patent
Estimating the term…
Abstract
A method of producing a bonded wire connection between an electronic component or a subassembly and a carrier by introducing energy from an ultrasound transducer into a wire that is to be bonded. According to this method, during the introduction of energy the impedance of the ultrasound transducer is measured as a function of time. The shape of the curve representing this time dependence is evaluated on the basis of a pre-specified comparison criteria, and the power input to the ultrasound transducer and/or a bond weight exerted on the wire is/are controlled in dependence on the result of this evaluation. A device usable for carrying out this method is also described.
Claims27
A method of producing a bonded wire connection between an electronic component or subassembly and a carrier by introducing energy from an ultrasound transducer into a wire that is to be bonded, the method comprising:
- measuring an impedance of an ultrasound transducer as a function of time while introducing energy from the transducer into a wire;
- evaluating a shape of a curve representing impedance time dependence on a basis of pre-specified comparison criteria;
- and
- controlling at least one of energy fed to the ultrasound transducer and a bond weight exerted on the wire, dependent on a result of the evaluating.
A method of testing the quality of a bonded wire connection between an electronic component or subassembly and a carrier, the connection having been produced by introducing energy into a wire that is to be bonded by means of an ultrasound transducer, the method comprising:
- measuring an impedance of an ultrasound transducer as a function of time during introduction of energy from the transducer to a wire,
- evaluating a shape of a curve representing time-dependence of the impedance on a basis of pre-specified comparison criteria;
- and
- using a result of the evaluation to automatically derive a decision about the quality of the bonded wire connection.
A device for producing a bonded wire connection between an electronic component or subassembly and a carrier by introducing energy from an ultrasound transducer into a wire that is to be bonded, the device comprising:
- an impedance-measuring device associated with an ultrasound transducer, the impedance-measuring device providing an output;
- a recording device connected to the output of the impedance-measuring device for recording a time dependence of the output signal of the impedance-measuring device in a predetermined time period during a bonding process for signalling purposes;
- at least one of a timing control device and a bonding process control device connected to the recording device,
- an evaluation device configured to evaluate a curve of time dependence and provide an output;
- and
- at least one of a bond-weight control unit and a bond-power control unit and a decision stage connected to the output of the evaluation device, so as to send out a decision signal corresponding to an evaluated quality of the bonded connection.
A device for testing the quality of a bonded wire connection between an electronic component or subassembly and a carrier by introducing energy from an ultrasound transducer into a wire that is to be bonded, the device comprising:
- an impedance-measuring device associated with an ultrasound transducer;
- a recording device for recording a time dependence of an output signal of the impedance-measuring device in a predetermined time period during a bonding process;
- an evaluation device to evaluate a curve of time dependence;
- and
- a decision stage connected to an output of the evaluation device and configured to send out a decision signal that characterizes the quality of the bonded connection.
A wire bonder comprising:
- an impedance-measuring device associated with an ultrasound transducer;
- a recording device for recording a time dependence, of an output signal of the impedance-measuring device in a predetermined time period during a bonding process;
- an evaluation device configured to evaluate a curve of time dependence;
- and
- at least one of a bond-weight control unit and a bond-power control unit connected to an output of the evaluation device.
Dependencies are inferred from the claim text.