Patent ID: 8157157

Claim:
A solder ball loading method for loading solder balls on connection pads of a sheet printed wiring board, comprising multiple printed wiring boards each of which has a respective connection pad formation region that includes a plurality of said connection pads, the method comprising: forming a solder resist layer on the sheet printed wiring board, the solder resist layer having openings each of which expose at least part of a respective connection pad within the connection pad formation regions of each of the printed wiring boards; applying a flux on an entire surface of each of the connection pad formation regions such that the connection pads of each of the printed wiring boards are covered with the flux; preparing a mask including: a mask main body having multiple opening groups, each opening group corresponding to each respective connection pad formation region of the sheet printed wiring board, and each opening group including a plurality of openings corresponding to the plurality of connection pads of the connection pad formation region, and a spacer interposed between the printed wiring board and the mask main body having multiple spacer opening portions, each spacer opening portion corresponding to each respective opening group having the plurality of openings of the mask main body, wherein a diameter of said openings of the mask main body is larger than a diameter of a respective opening of the solder resist layer, the spacer contacting only an area of the printed wiring board where no flux is provided, and a connection pad formation region being smaller than the opening portion of the spacer; aligning the openings of the mask main body to face the respective connection pads of the printed wiring board; and supplying the solder ball to the mask; and dropping the solder ball on the connection pad having flux thereon, through one of the plurality of openings of the mask main body.