Abstract: For dispensing solder on a substrate, a soldering wire and a forming gas heated to a predetermined temperature are fed to a mixing chamber of a two-component nozzle so that, in the mixing chamber, solder is melted off and carried with the gas stream. The solder blown out of the two-component nozzle settles on the substrate. The two-component nozzle is moved or swivelled relative to the substrate in order to distribute the solder over a predetermined area of the substrate.

Abstract: A Wire Bonder comprises a bondhead that can be moved in a horizontal plane that has a capillary clamped to a horn and parts of an image recognition system. The tip of the capillary and the optical axis of the image recognition system are separated by a vectorial distance D. The Wire Bonder has a device with a body with an optical marking and with two stop faces that enable the vectorial distance D to be recalibrated at any time. The control program of the Wire Bonder is set up on the one hand to move the capillary towards the first stop face and to determine a first co-ordinate xC of the position of the bondhead as soon as the capillary touches the first stop face and then to move the capillary towards the second stop face and to determine a second co-ordinate yC of the position of the bondhead as soon as the capillary touches the second stop face.

Abstract: A Wire Bonder is designed in such a way and equipped with the appropriate means so that in production the current bond cycle is completed in all possible cases such as interruption of the electrical power supply, failure of the compressed air, failure of the vacuum, actuation of the emergency switch, triggering a stop signal caused by the response of a safety mechanism. A bond cycle is to be understood as one single bonding process with which the bond wire is attached to a connection point of the semiconductor chip, formed into a wire loop and attached to a connecting point of the substrate and with which the wire is then tom away from the finished wedge bond.

Abstract: A device for measuring the oscillation amplitude of the tip of a capillary by means of a light beam comprises a light source and an opto-receiver and two apertured diaphragms that are arranged between the light source and the opto-receiver and which lie on a common axis. The apertured diaphragms are preferably formed by means of drill holes arranged on a common axis in side walls of a channel formed in a body. The two apertured diaphragms define the diameter of the light beam.

Abstract: The picking of a semiconductor chip from a foil takes place by means of a chip gripper which bears on a bondhead and can be deflected in a predetermined direction and with the aid of a needle. An inductive sensor serves the precise measurement of the deflection of the chip gripper with reference to the bondhead.

Abstract: A device for the metered delivery of a viscous liquid has a pump body with a drill hole accommodating two pistons which connects a first chamber serving as an intake chamber and a second chamber serving as a discharge chamber. Two swivel arms driven by two cam discs are foreseen as the drive mechanism for the back and forth movement of the two pistons. For the metered delivery of an adhesive which contains flakes of silver the drill hole is designed such that it serves for guiding the pistons as well as for sealing the pump path.

Abstract: With a device for the formation of a wire ball at the end of a wire an in and out swivelling electrode with an oblong shape is connected to the shaft of a motor directly or indirectly via a connecting piece so that the electrode is essentially rotated on its longitudinal axis when swivelling in and out. The mass inertia of the electrode is low as regards the rotational axis which is why it can be turned with negligible expenditure of energy. On swivelling in and out, the electrode is turned back and forth between a lower limit position in which a surface necessary for creating the spark, the so-called firing lug is located underneath the capillary of the Wire Bonder and an upper limit position in which the firing lug is located laterally elevated next to the capillary.

Abstract: A device with electrodes for the formation of a ball at the end of a wire protruding out of a capillary comprises a first electrode which has a tip and at least one further electrode. The first electrode and the at least one further electrode are electrically connected. The distance between the tip of the first electrode and the end of the wire is smaller than the distance between any point on the at least one further electrode and the end of the wire.

Abstract: In order that, on wire bonding by means of a Wire Bonder, optimum bonding results can be achieved after a capillary change it is suggested that, after a change from a first capillary to a second capillary, the ultrasonic transducer which applies ultrasonics to the horn which guides the capillary is controlled with a parameter P2 which results from the parameter P1 before the capillary change as P2=g(k1, k2)*P1 or P2=g(k1, k2, A1, A2)*P1 or P2=g(k1, k2, A1, A2, H1, H2)*P1, whereby the quantities k1 and k2 designate the estimated values for the flexural strength, the quantities A1 and A2 the amplitudes of the freely oscillating capillary and H1 and H2 the diameters in the narrowest part of the longitudinal drill hole of the first or second capillary and whereby the function g is a predetermined function.

Abstract: Optimum bond parameters for a bond force FB and an ultrasonic variable PB and, optionally, at least one further bond parameter GB of a Wire Bonder for ball bonding can be determined by means of a method with which a predetermined number of bond cycles is carried out, whereby the bond parameters to be optimised are each varied within a predefined range, whereby with each bond cycle n, after attachment of the wire ball to the connection point of the semiconductor chip, the following steps are carried out:

Abstract: A device for the metered delivery of a viscous liquid has a pump body with a drill hole accommodating two pistons which connects a first chamber serving as an intake chamber and a second chamber serving as a discharge chamber. Two swivel arms driven by two cam discs are foreseen as the drive mechanism for the back and forth movement of the two pistons. For the metered delivery of an adhesive which contains flakes of silver the drill hole is designed such that it serves for guiding the pistons as well as for sealing the pump path.

Abstract: On measurement of a component Ay of the amplitude of the oscillations of the tip of a capillary which is clamped to a horn to which ultrasonics can be applied from an ultrasonic transducer, whereby measurement is based on the shading of a light beam by the capillary and whereby the intensity of the light beam is measured by means of an opto-receiver, the capillary is placed at one side of the light beam without it shading the light beam and ultrasonics is applied to it. The capillary is then moved in steps through the light beam whereby, for each of the i=1 to n steps, the direct voltage portion UDC(yi) and the alternating voltage portion UAC(yi) of the output signal of the opto-receiver are determined as well as a co-ordinate yi whereby the co-ordinate yi designates the position of the capillary in relation to a co-ordinate axis y running perpendicularly to the light beam. The amplitude Ay is then calculated from the values measured.

Abstract: A clamping element for the transport of a substrate in a predefined transport direction comprises a first and a second leg with a first and second clamping jaw for clamping a substrate. Each of the two clamping jaws has a clamping plate which is movable in transport direction relative to the corresponding leg. A sensor measures the deflection of the first clamping plate relative to the first leg. As soon as the measured deflection exceeds a predefined threshold value, the clamping element is opened.

Abstract: A pressure transducer for the production of a controlled under or overpressure comprises a valve to which compressed air can be applied, a motor for adjusting the position of the valve block, a sensor for measuring the pressure to be controlled and an electronic controller. The valve comprises a valve block working together with a valve seat. The rotational movement of the shaft of the motor is converted into a longitudinal movement of the valve block by means of a coupling. Between the shaft of the motor and the valve block, a spring is inserted which applies a mechanical load to the motor so that the motor does not reach the set speed given by the controller but turns slower. The load on the motor is dependent on the position of the valve block. For the controller, this is equivalent to a linearization of the characteristic curve of the regulated system.

Abstract: With a device for the formation of a wire ball at the end of a wire an in and out swivelling electrode with an oblong shape is connected to the shaft of a motor directly or indirectly via a connecting piece so that the electrode is essentially rotated on its longitudinal axis when swivelling in and out. The mass inertia of the electrode is low as regards the rotational axis which is why it can be turned with negligible expenditure of energy. On swivelling in and out, the electrode is turned back and forth between a lower limit position in which a surface necessary for creating the spark, the so-called firing lug is located underneath the capillary of the Wire Bonder and an upper limit position in which the firing lug is located laterally elevated next to the capillary.

Abstract: A pick-up tool for the mounting of semiconductor chips onto a substrate has a suction device which consists of a plate made out of a dimensionally stable material one surface of which has structures made of hardened adhesive. The material for the plate is, for example, aluminum, a carbon fiber composite material or a dimensionally stable plastic. A suitable material for the structure is, for example, an adhesive which has Teflon® as the filing material.

Abstract: A device with electrodes for the formation of a ball at the end of a wire protruding out of a capillary comprises a first electrode which has a tip and at least one further electrode. The first electrode and the at least one further electrode are electrically connected. The distance between the tip of the first electrode and the end of the wire is smaller than the distance between any point on the at least one further electrode and the end of the wire.

Abstract: A Wire Bonder has a capillary clamped to a horn. An ultrasonic transducer applies ultrasonics to the horn whereby the ultrasonic transducer is controlled by a parameter P. For calibration of the parameter P, a pizoresistive sensor integrated into a semiconductor chip is used. The capillary is lowered onto the semiconductor chip and a bond force is applied to it. Afterwards, a value P1 of the parameter P is applied to the ultrasonic transducer and the output signal of the sensor is stored as the reference value URef as soon as the transient reaction is concluded. The bond force is selected great enough so that the capillary does not slide back and forth. The Wire Bonder, for example after changing the capillary, is then recalibrated in that a correction factor &ggr; is analogously determined so that the amplitude of the sensor signal assumes the value URef when the ultrasonic transducer is operated with the value P2=&ggr;*P1.

Abstract: With the mounting of a semiconductor chip onto a substrate having a portion of adhesive the bondhead is lowered to a predetermined height H above a support holding the substrate. At the same time, the pick-up tool is fixed in an upper limit position on the bondhead. As soon as the bondhead has reached the height H, the fixing of the pick-up tool is released so that the pick-up tool moves downwards from the upper limit position and presses the semiconductor chip onto the adhesive. After a predetermined time after releasing the fixing of the pick-up tool, the bondhead is raised and moved away. With a bondhead particularly suited for the method, the pick-up tool and the bondhead are connected by means of a chamber to which compressed air and/or vacuum can be applied so that, to a large extent, the movement of the pick-up tool can be controlled.

Abstract: To determine the vectorial distance D between the tip of a capillary and an optical axis of an image recognition system of a Wire Bonder, a glass fibre supplied with light is used as a reference point and as a sensor. On the one hand, the glass fibre serves as a reference point with which the position of the optical axis of the image recognition system can be determined. On the other hand, the glass fibre serves as a sensor with which the position of the tip of the capillary can be determined in that it is determined at which position of the bondhead the intensity of the light which is reflected back into the glass fibre by a wire ball formed at the tip of the capillary is at a maximum.