CORE-SHELL BALL GRID ARRAY MATERIALS FOR LARGE FORM FACTOR INTEGRATED CIRCUIT PACKAGES

Abstract: solder materials, solder balls, and solder features, and microelectronic devices and systems deploying the solders are discussed. a solder ball includes an inner core that is an alloy of tin, silver, and copper, which has a relatively high melting point. surrounding the inner core is a shell or cladding of a tin-bismuth alloy having a lower melting point. an optional nickel coating is on the inner core and between the inner core and the shell or cladding. during surface mount, the lower melting point the tin-bismuth alloy is used as the reflow temperature.

Inventor(s): Rui Zhang, Jiaqi Wu, Brian Franco, Xiao Lu, Mukul Renavikar

CPC Classification: H01L24/13 (SEMICONDUCTOR DEVICES NOT COVERED BY CLASS (use of semiconductor devices for measuring ; resistors in general ; magnets, inductors or transformers ; capacitors in general ; electrolytic devices ; batteries or accumulators ; waveguides, resonators or lines of the waveguide type ; line connectors or current collectors ; stimulated-emission devices ; electromechanical resonators ; loudspeakers, microphones, gramophone pick-ups or like acoustic electromechanical transducers ; electric light sources in general ; printed circuits, hybrid circuits, casings or constructional details of electrical apparatus, manufacture of assemblages of electrical components ; use of semiconductor devices in circuits having a particular application, see the subclass for the application))

Search for rejections for patent application number 20250218992