Patent ID: 7845547

Claim:
A method for manufacturing a printed wiring board having a bump, comprising: forming a solder-resist layer having a small-diameter aperture and a large-diameter aperture, each aperture exposing a respective conductive pad of the printed wiring board; printing a solder paste in the large-diameter aperture in the solder-resist layer, but not printing the solder paste in the small-diameter aperture in the solder resist layer; loading a solder ball in each of the large-diameter aperture and the small-diameter aperture using a mask having aperture areas that correspond to the small-diameter aperture and large-diameter aperture of the solder-resist layer; forming a small-diameter bump from the solder ball in the small-diameter aperture; and forming a large-diameter bump from both the solder paste and the solder ball in the large-diameter aperture, wherein the loading a solder ball comprises: positioning a cylinder member having an aperture area that faces an upper side of the mask; aggregating the solder balls on the mask immediately below the cylinder member by inrushing air to the aperture area of the cylinder member; and loading the aggregated solder balls in the small-diameter aperture and the large-diameter aperture in the solder-resist layer through the aperture areas of the mask by moving the cylinder member relative to the mask.