Magnetic pre-alignment of semiconductor device chips for bonding

Claim 2

Apparatus for prealigning semiconductor device chips having soft ferromagnetic integral leads thereon with corresponding fingers of a lead frame structure to promote subsequent consistent prEcision engagement therebetween for bonding, said apparatus comprising: a template having two major parallel surfaces and a plurality of recesses in one of said surfaces; a conductive lead frame structure having sets of soft ferromagnetic fingers said sets being located in said lead frame so as to correspond to said template recesses, said lead frame fingers having free end portions which correspond to the integral lead pattern on a semiconductor device chip; a first means for holding the lead frame substantially against said one template surface; a magnetic plate coextensive and contiguous the opposite surface of the template, said plate having two major faces serving as opposing poles of a magnet; a second means for concentrating the magnetic force from the plate in the areas of the template recesses; means for temporarily securing said first means, said lead frame, said template, and said magnetic plate together in mutual registration wherein said sets of lead frame fingers overlie said template recesses; and means for vibrating said template so that all of the semiconductor device chips in the template recesses are automatically prealigned, with the integral chip leads being brought into close proximity with their corresponding lead frame finger-free ends thereby promoting subsequent consistent precision engagement therebetween for bonding.

Claim 3

Apparatus for prealigning semiconductor device chips having soft ferromagnetic integral leads thereon with conductive lead frame structures to promote subsequent consistent precision engagement therebetween for bonding, said apparatus comprising: a template having two major parallel surfaces, a plurality of recesses in one of said surfaces, said recesses being located in spaced rows and columns, said recesses having an opening extending to the opposite surface of said template; a conductive lead frame structure having sets of soft ferromagnetic fingers, said sets being located in spaced rows and columns corresponding to said template recesses, said lead frame fingers having free ends corresponding to the integral lead pattern on the semiconductor chips to be located in the template recesses; a first means for holding said lead frame substantially against said one template surface; a rubbery strip coextensive and contiguous the opposite surface of the template, said strip having two major faces serving as opposite poles of a permanent magnet, soft ferromagnetic pins extending from one face of said rubbery strip, said pins being located in spaced rows and columns corresponding to said openings in said template, said pins being inserted in said openings so that said pins extend partially therethrough; means for temporarily securing said first means, said lead frame, said template, and said rubbery strip together in mutual registration wherein said sets of lead frame fingers overlie said template recesses and said pins remain inserted in the template openings; and means for vibrating said template so that all of the semiconductor chips located in the template recesses can be automatically prealigned, with the integral chip leads being brought into close proximity with their overlying corresponding lead frame finger-free ends thereby promoting subsequent consistent precision engagement therebetween for bonding.

Claim 4

Apparatus for prealigning semiconductor device chips having soft ferromagnetic integral leads thereon with conductive lead frame structures to promote subsequent consistent precision engagement therebetween for bonding, said apparatus comprising: a template having two major parallel surfaces, a plurality of recesses in one of said surfaces, said recesses being located in spaced rows and columns, said recesses having an opening extending to the opposite surface of said template; a conductive lead frame structure having sets of soft ferromagnetic fingers, said sets being located in spaced rows and columns corresponding to said template recesses, said lead frame fingers having free ends corresponding to the integral lead pattern on the semiconductor chips to be located in the template recesses; a first means for holding said lead frame substantially against said one template surface; a rubbery strip coextensive and contiguous the opposite surface of the template, said strip having two major faces serving as opposite poles of a permanent magnet, soft ferromagnetic pins extending from one face of said rubbery strip, said pins being located in spaced rows and columns corresponding to said openings in said template, said pins being inserted in said openings so that said pins extend partially therethrough; means for temporarily securing said first means, said lead frame, said template, and said rubbery strip together in mutual registration wherein said sets of lead frame fingers overlie said template recesses and said pins remain inserted in the template openings; and means for vibrating said template so that all of the semiconductor chips located in the template recesses can be automatically prealigned, with the integral chip leads being brought into close proximity with their overlying corresponding lead frame finger-free ends thereby promoting subsequent consistent precision engagement therebetween for bonding.