Patent ID: 6125043
Filing Date: 2000-09-26
Classification: H01L,H05K,Y02P,Y10S,Y10T

Abstract:
A circuit board arrangement comprisinga component (101) having a pad (102);a circuit board (1) on which said component (101) is mounted, said circuit board having another pad (2) electrically connected to said pad (102) on the component (101);stand-offs (20) between the component (101) and the circuit board (1) for holding said component (101) at a predetermined distance from said circuit board (1); anda portion (105) of solder extending between said component (101) and said circuit board (1) and acting to provide an automatic passive alignment of said component (101) on said circuit board and to provide an electrical connection between said pad (102) on said component and said another pad (2) on said circuit board;wherein said electrical connection between said pads is made and said automatic passive alignment occurs by a method including the steps of:dividing a contacting surface of said portion (105) of said solder contacting said another pad (2) on said circuit board (1) into a central zone and at least one peripheral edge zone;alloying said solder in said central zone more strongly with one material in a center part (3) of said another pad (2) contacting said solder than said solder in said at least one peripheral edge zone; andmelting said portion (105) of said solder extending between said pads to form a melted piece of the solder, allowing the melted piece to solidify and selecting the dimensions of said stand-offs so that said component (101) is drawn to rest on said stand-offs (20) on said circuit board and said automatic passive alignment of said component is provided by action of surface tension in said melted piece of said solder during solidification of said melted piece.