Method of manufacturing thick-film circuit devices
Method of screening paste solder onto leaded hybrid substrates
Method and transfer plate for applying solder to component leads
Method and apparatus for solder bumping of printed circuit boards
Microbeam laser machine for acting on objects having thin layers of material
Process of fabricating a circuit package
Method of making high density solder bumps and a substrate socket for high density solder bumps
ApplicationNo. 510401 filed on 08/02/1995
US Classes:438/616, By transcription from auxiliary substrate228/180.22, Lead-less (or "bumped") device257/E21.503, Encapsulation of active face of flip chip device, e.g., under filling or under encapsulation of flip-chip, encapsulation perform on chip or mounting substrate (EPO)257/E21.508, Forming solder bumps (EPO)257/E21.511, Mounting on insulating member provided with metallic leads, e.g., flip-chip mounting, conductive die mounting (EPO)257/E23.021, Bump or ball contacts (EPO)257/E23.061, Leads being also applied on sidewalls or bottom of substrate, e.g., leadless packages for surface mounting (EPO)257/E23.067, Via connections through substrates, e.g., pins going through substrate, coaxial cables (EPO)257/E23.068Additional leads joined to metallizations on insulating substrate, e.g., pins, bumps, wires, flat leads (EPO)
ExaminersPrimary: Graybill, David E.
Attorney, Agent or Firm
Foreign Patent References
International ClassesH01L 021/288
AbstractA process within substrate is provided with vias communicating with surface contacts or bumps. Joining material paste is forced through holes in a screen onto an area array of the contacts on the substrate then the screen is biased against the substrate as the paste is heated and cooled to transfer the joining material onto the contacts. Alternately, joining material paste is forced into the screen and then a substrate is placed onto the screen with an area array of bump contacts of the substrate in contact with the solder paste, and then the paste is heated and cooled to transfer the material onto the bumps. The joining material may be a solder paste, conductive adhesive paste, or transient liquid bond paste. The substrate may be a semiconductor chip substrate, flexible or rigid organic substrate, or a metal substrate coated to form a dielectric surface. Also, the substrate may be a computer chip, chip carrier substrate or a circuit board substrate. The process may be used to produce flip chips, ball grid array modules, column grid array modules, circuit boards, and attachment structures of the preceding components including information handling systems.