公开(公告)号：SG48462A1

公开(公告)日：1998-04-17

申请号：SG1996010224

申请日：1996-07-06

Applicant: IBM

Inventor： PAPATHOMAS KONSTANINOS I ,  FUERNISS STEPHEN JOSEPH ,  DITTRICH DEBORAH LYNN ,  WANG DAVID WEI

IPC: C08G59/18 ,  C08F2/48 ,  C08G59/00 ,  C08G59/68 ,  C08G73/02 ,  H01L23/29 ,  H01L23/31 ,  H05K3/28 ,  H05K3/34 ,  H01L23/48

Abstract: An electronic package assembly where a low profile integrated circuit chip package is soldered to an organic (e.g., epoxy resin) substrate, e.g., a printed circuit board or card, the projecting conductive leads of the integrated circuit chip package and the solder which substantially covers these leads (and respective conductors on the substrate) having been substantially covered with ultraviolet photocured encapsulant material (e.g., an epoxy resin or a cyanate with a photoinitiator and silica) to provide reinforcement for the solder-lead connections. The encapsulant material is dispensed about the solder and lead joints following solder reflow and solidification so as to substantially surround the solder and any portions of the leads not covered with solder.

公开(公告)号：DE68925596D1

公开(公告)日：1996-03-21

申请号：DE68925596

申请日：1989-04-25

Applicant: IBM

Inventor： FEILCHENFELD NATALIE BARBARA ,  FUERNISS STEPHEN JOSEPH ,  GLENNING JOHN JOSEPH ,  PAWLOWSKI WALTER PAUL ,  PHELAN GIANA MARRONE ,  RICKERL PAUL GEORGE

IPC: H05K3/06 ,  G03F7/038 ,  G03F7/16 ,  G03F7/32 ,  H01L21/768 ,  H01L23/522 ,  H05K1/03 ,  H05K3/46

Abstract: A polyimide pattern is formed on a substrate by providing a layer of photosensitive polyimide precursor containing the polyimide precursor and a compound having a photosensitive group on the substrate and prebaking the layer. The layer is then exposed imagewise to actinic radiation through a photomask to form an exposed image pattern of the polyimide precursor in the layer. The unexposed areas of the layer are removed using a liquid developer and the exposed image pattern is cured by heating. In one aspect of the present invention, the prebaking step employs a judicious selection of times and temperatures to eliminate the problem of formation of a white residue that occurs from using prior art prebake procedures. In another aspect of the present invention, a particular liquid developer composition is employed to facilitate the formation of sloped vias in the polyimide. In another aspect of the present invention, a particular range of exposure wavelength(s) is employed to obtain smooth walled vias.