Method and apparatus for bonding miniature semiconductor pill-type components to a circuit board

Claim 5

In an apparatus for transferring a miniature semiconductor pill-type component from a temporary carrier lead frame and directly soldering said component to a printed circuit board, said apparatus including means for supporting a lead frame having a plurality of spaced semiconductor pill-type components temporarily attached thereto, each component having a disc-shaped plastic body encapsulating a semiconductor device chip with a diameter of Db and a plurality of discrete leads for said chip radially extending from the body with the outer portions of the leads defining a diameter of D1, said lead frame having two diametrically opposite holding tabs partially extending into the component body and providing temporary support therefor, means for supporting a printed circuit board having a plurality of mutually spaced convergent solder coated conductors corresponding to said component leads, and visual enlargement means for viewing alignment of said component leads with their corresponding circuit board conductors; a combination transfer and soldering tool comprising: a metallic, open ended tube, said tube having a bore extending longitudinally throughout its entire length, said bore being circular with a diameter larger than Db yet smaller than D1 whereby one may view inner portions of said component leads and said circuit board conductors for purposes of alignment by looking through said bore in said tube with said visual enlargement means, said tube having a generally flat end surface adapted for engaging said component leads, two diametrically opposite slots in said tube end surface corresponding to said lead frame holding tabs, a rigid, metallic arm connected to said tube being spaced from said end surface and projecting from said tube, means for heating said tube communicating with said arm wherein heat is conductively transferred to said end surface to heat it to a temperature above the melting point of the solder on said circuit board conductors, and wherein means for downwardly moving said tube may cooperate with said arm to engage said tube end surface with said component leads to press them against said circuit board conductors for soldering and so that said lead frame holding tabs are automatically pulled from said component body by coaction with said slots in said tube end surface.

Claim 6

In an apparatus for transferring a miniature semiconductor pill-type component from a temporary carrier lead frame and directly soldering said component to a printed circuit board, said apparatus including means for supporting a lead frame having a plurality of spaced semiconductor pill-type components temporarily attached thereto, each component having a disc-shaped plastic body encapsulating a semiconductor device chip with a diameter of Db and a plurality of discrete leads for said chip radially extending from the body with the outer portions of the leads defining a diameter of D1, said lead frame having two diametrically opposite holding tabs partially extending into the component body and providing temporary support therefor, means for supporting a printed circuit board having a plurality of mutually spaced convergent solder coated conductors corresponding to said component leads, and visual enlargement means for viewing alignment of said component leads with their corresponding circuit board conductors; a combination transfer and soldering tool comprising: a metallic, open ended tube, said tube having a bore extending longitudinally throughout its entire length, said bore being circular with a diameter larger than Db yet smaller than D1 whereby one may view inner portions of said component leads and said circuit board conductors for purposes of alignment by looking through said bore in said tube with said visual enlargement means, said tube having a generally flat end surface adapted for engaging said component leads, two diametrically opposite slots in said tube end surface corresponding to said lead frame holding tabs, a rigid, metallic arm connected to said tube being spaced from said end surface and projecting from said tube, means for heating said tube communicating with said arm wherein heat is conductively transferred to said end surface to heat it to a temperature above the melting point of the solder on said circuit board conductors, and wherein means for downwardly moving said tube may cooperate with said arm to engage said tube end surface with said component leads to press them against said circuit board conductors for soldering and so that said lead frame holding tabs are automatically pulled from said component body by coaction with said slots in said tube end surface.

Claim 7

Apparatus for transferring a miniature semiconductor pill-type component from a temporary carrier lead frame and directly soldering said component to a printed circuit board, said apparatus comprising: means for supporting a lead frame having a plurality of spaced semiconductor pill-type components temporarily attached tHereto, each component having a plastic body encapsulating a semiconductor device chip and a plurality of discrete leads for said chip radially extending from the body, said lead frame having at least two holding tabs which extend partially into said component body thereby providing temporary support for said component; means for supporting a printed circuit board having a plurality of mutually spaced, convergent solder-coated conductors thereon which correspond to said component leads; means for maintaining said lead frame parallel with and within about 0.25 inch above said circuit board; a combination transfer and soldering tool positioned above one of said components, said tool being a metallic, tubular open ended tube with an end surface adapted to engage said component leads, said tool having a bore extending throughout its entire length, said bore being larger than said component body yet smaller than the periphery defined by the outer portions of said component leads, at least two slots in said tool end surface corresponding to said holding tabs in the lead frame structure; means for continually heating said tool end surface to a temperature above the melting point of the solder on said circuit board conductors; visual enlargement means positioned above said tool in mutual registration with said bore wherein one can view inner portions of said component leads and conductors by looking through said bore in said tool; means for aligning said component leads with their corresponding circuit board conductors wherein said alignment can be observed by looking through said bore in said tool; means for moving said tool toward said circuit board to engage said tool end surface with said component leads to sequentially bend said component leads toward said circuit board conductors, automatically tear said lead frame holding tabs from said component body by coaction with said tool slots after maintenance of lead conductor alignment is assured and finally, to clamp said leads against their corresponding circuit board conductors thereby permanently soldering said component to said circuit board with the heated tool.

Claim 8

Apparatus for transferring a miniature semiconductor pill-type component from a temporary carrier lead frame and directly soldering said component to a printed circuit board, said apparatus comprising: means for supporting a lead frame having a plurality of spaced semiconductor pill-type components temporarily attached tHereto, each component having a plastic body encapsulating a semiconductor device chip and a plurality of discrete leads for said chip radially extending from the body, said lead frame having at least two holding tabs which extend partially into said component body thereby providing temporary support for said component; means for supporting a printed circuit board having a plurality of mutually spaced, convergent solder-coated conductors thereon which correspond to said component leads; means for maintaining said lead frame parallel with and within about 0.25 inch above said circuit board; a combination transfer and soldering tool positioned above one of said components, said tool being a metallic, tubular open ended tube with an end surface adapted to engage said component leads, said tool having a bore extending throughout its entire length, said bore being larger than said component body yet smaller than the periphery defined by the outer portions of said component leads, at least two slots in said tool end surface corresponding to said holding tabs in the lead frame structure; means for continually heating said tool end surface to a temperature above the melting point of the solder on said circuit board conductors; visual enlargement means positioned above said tool in mutual registration with said bore wherein one can view inner portions of said component leads and conductors by looking through said bore in said tool; means for aligning said component leads with their corresponding circuit board conductors wherein said alignment can be observed by looking through said bore in said tool; means for moving said tool toward said circuit board to engage said tool end surface with said component leads to sequentially bend said component leads toward said circuit board conductors, automatically tear said lead frame holding tabs from said component body by coaction with said tool slots after maintenance of lead conductor alignment is assured and finally, to clamp said leads against their corresponding circuit board conductors thereby permanently soldering said component to said circuit board with the heated tool.