Kabushiki Kaisha Shinkawa

Shinkawa Ltd.

Kazumasa Sasakura

Osamu Nakamura

Yoshimitsu Terakado

Yoshihito Hagiwara

Hiroaki Yoshino

Shigeru Shiozawa

Yuki Sekine

Tatsuyuki Sunada

A discharge examination device for examining discharge of a wire-bonding apparatus that applies a voltage between a torch electrode and a wire to procure the discharge therebetween includes a current detection unit, a timer unit and a discharge determination unit. The current detection unit detects a discharge current flowing through the wire. The timer unit measures discharge detection time after application of the voltage before detection of the discharge current. The discharge determination unit determines whether or not the discharge is abnormal based on the discharge detection time. With this, a discharge examination device, a wire-bonding apparatus, and a discharge examination method that are capable of detecting abnormality of discharge are provided.

Discharge examination device, wire-bonding apparatus, and discharge examination method

A ball forming devicefor forming a ballat a tip of a wireby producing discharge between a torch electrodeand the tip of the wire, the device includes: a current supply unitconfigured to supply a ball-forming current between the torch electrodeand the tip of the wire; and a current control unitconfigured to control the current supply unit, so that a signal of the ball-forming current for a predetermined period includes a first period in which the signal takes a predetermined current value and a second period including a triangle wave. With this, it is possible to provide a ball forming device, a wire-bonding apparatus, and a ball formation method that are capable of suppressing formation of deformed balls.

Ball forming device, wire-bonding apparatus, and ball formation method

A wire bonding apparatus equipped with a capillary through which a wire is passed, a torch electrode which is installed in a substantially horizontally movable manner so as to be positioned beneath the capillary, and a torch electrode driver which drives the torch electrode, in which the torch electrode is directly coupled to an output shaft of a pulse motor which is driven by a high-resolution angle control circuit, so that a resolution of the pulse motor obtained by the high-resolution angle control circuit is 30,000 parts per revolution or greater.

Wire bonding apparatus

A bonding apparatus comprising a capillary through which a wire passes, a torch electrode that makes a substantially horizontal pivotal movement so as to be brought under the capillary, and a rotary motor that drives the torch electrode, thus allowing the torch electrode to have any desired range of movement so as to provide superior working characteristics.

A device and method is available for detecting abnormalities of an electric discharge generated for forming a ball at the end of a bonding wire in a bonding apparatus. A high voltage is applied across the bonding wire and an electrode, and the maximum value of the applied high voltage is detected and sent, via a peak hold circuit, to a computer that compares the maximum high voltage with an insulation breakdown voltage of a normal detection range and calculates a gap between the end of the bonding wire and the electrode, thus determining the discharge abnormalities based upon the result of the calculation of the gap.

Discharge abnormality detection device and method for use in wire

To assure the continuity of bonding by preventing any buckling of a covered wire or slipping-off of the covered wire from a second clamper, the second clamper is caused to vibrate while a capillary and first clamper are being raised to a ball formation level after the first clamper is closed and the second clamper is opened in the step of raising the capillary and first clamper to the ball formation level, thus preventing the covered wire from sticking to the second clamper.

Method for wire-bonding a covered wire

To prevent melting and scattering of a covering-film during ball formation, the covering-film, at the time a ball is formed, has been completely removed from the portion of a covered wire which corresponds to the tail length that protrudes from the tip of a capillary.

A method for cleaning a bonding tool of a bonding apparatus includes a step of positioning a tip portion of the bonding tool between a pair of discharge electrodes, which are primarily used for removing a covering that covers a bonding wire, and a step of causing an electrical discharge across the discharge electrodes by applying a high voltage, such as of 3500 V, by connecting the discharge electrodes to positive and negative poles of a discharge power source, respectively. The electrical discharge is performed with the bonding wire kept inside the bonding tool so as not to project out of the bonding tool or after the bonding wire is removed from the bonding tool.

Method for cleaning a bonding tool used on covered bonding wires

In a wire-bonding machine and method that uses a covered wire, discharge electrodes comprise a pair of discharge electrodes for covering-film removal, in which the upper and lower surfaces of electromagnetic parts used as discharge terminals are held by two insulating parts, and a discharge electrode for ball formation, which is movable together with one of the pair of discharge electrodes for covering-film removal. The discharge electrodes for covering-film removal are positioned so as to be in close proximity to, but not in contact with, the side surfaces of the portion of the covered wire corresponding to an intended second bonding point during the removal of the covering-film from the portion corresponding to the intended second bonding point, and the discharge electrode for ball formation is positioned to one side of the covered wire when the discharge electrodes for covering-film removal are opened, and when the capillary is raised to the ball formation level, the tip of the covered wire is positioned to one side of the discharge electrode for ball formation.

Wire-bonding apparatus and method using a covered wire

To assure that a loop height remains constant even if the wiring distance should vary and no slack is generated in the hypotenuse of the bonded wire: the length of the covered wire required for a next wiring operation is set by a formula which combines a first-order function of a wiring distance, a first-order reciprocal function of the wiring distance and a constant; the covering-film at the corresponding position is removed; and the exposed-core portion of the covered wire from which the covering-film has been removed is bonded to the lead of a lead frame with the loop height fixed even if the wiring distance should change.

To assure a continuity of bonding by preventing buckling of a covered wire and slipping-off of the covered wire from a second clamper, after a first clamper is closed and the second clamper is opened in a step in which a capillary and first clamper are raised to a ball formation level, the capillary and first clamper are lowered, thus pulling the covered wire downward so that the covered wire does not stick to the second clamper; and then the capillary and first clamper are raised to the ball formation level.

In a method and apparatus for making uniform size balls at the end of bonding wires, a constant current circuit is installed between a high voltage power source and a discharge electrode so that a constant high voltage is applied between the bonding wire end and the discharge electrode and a discharge voltage is detected by a discharge voltage detecting circuit so that the thus detected discharge voltage is converted into a time so that a discharge time setting circuit which controls the constant current circuit regulates the discharge time period of the high voltage.

Growing community of inventors

Musashi Murayama, Japan

Kazumasa Sasakura