Abstract The bonding of multiple leads on an individual basis is a tedious, time-consuming operation which is often impractical and uneconomical. For example, in bonding individual leads with a beam of radiant energy such as a laser beam, it is frequently impractical and uneconomical to align the lead with a bonding site, align the bonding site and the lead with the beam of radiant energy, apply the laser beam and then repeat the process for each lead to be bonded. As disclosed herein, a beam of radiant energy is shaped into a predetermined pattern so that the beam can be simultaneously applied to a plurality of leads. A composite cylindrical lens is disclosed, for example, which includes a plurality of cylindrical lens segments wherein a line formed by each segment when a collimated beam of radiant energy strikes the composite lens forms a side of a polygon. A perimeter pattern may be formed in this manner which is suitable for simultaneous multiple lead bonding. For example, in simultaneously bonding a plurality of leads extending from a beam leadlike device, the perimeter pattern may have essentially the same configuration as the device so that radiant energy may be applied simultaneously to the leads to be bonded without applying the radiant energy directly to the device itself.
A device for simultaneously bonding a plurality of leads extending from a first workpiece wherein the first workpiece is positioned relative to a second workpiece so that each lead is aligned with a bonding site on the second workpiece, the device comprising: means for generating a collimated beam of radiant energy; four cylindrical lens segments, each segment having a generally triangular configuration with one side of each segment substantially perpendicular to the cylindrical cross section of the segment, the segments being positioned relative to each other to form a generally rectangular composite cylindrical lens wherein the side of each segment perpendicular to the cylindrical cross section of the segment forms the sides of the generally rectangular composite cylindrical lens, said composite lens being positioned in the collimated beam of radiant energy so as to form two pairs of generally parallel lines at the focal plane of the composite lens which pairs of parallel lines intersect at generally right angles; and means for applying said pairs of parallel lines on the leads extending from the first workpiece to simultaneously bond the leads to their bonding sites without applying radiant energy directly to the first workpiece.
Claim 2
Independent Claim
194 words
A device for simultaneously bonding a plurality of leads extending from a first workpiece wherein the first workpiece is positioned relative to a second workpiece so that each lead is aligned with a bonding site on the second workpiece, the device comprising: means for generating a collimated beam of radiant energy; four cylindrical lens segments, each segment having a generally triangular configuration with one side of each segment substantially perpendicular to the cylindrical cross section of the segment, the segments being positioned relative to each other to form a generally rectangular composite cylindrical lens wherein the side of each segment perpendicular to the cylindrical cross section of the segment forms the sides of the generally rectangular composite cylindrical lens, said composite lens being positioned in the collimated beam of radiant energy so as to form two pairs of generally parallel lines at the focal plane of the composite lens which pairs of parallel lines intersect at generally right angles; and means for applying said pairs of parallel lines on the leads extending from the first workpiece to simultaneously bond the leads to their bonding sites without applying radiant energy directly to the first workpiece.
Claim 3
Dependent Claim
41 words
The device of claim 1, wherein the four cylindrical lens segments are substantially identical, each segment having the configuration of a right-angled isosceles triangle with the side opposite the right angle being perpendicular to the cylindrical cross section of the segment.