Patent ID: 7497365

Claim:
A paste coater for applying solder paste to arrays of bump electrodes that project outward from a semiconductor package, comprising: a sub frame; a transfer roller rotatably and horizontally supported at said sub frame; a roller drive mechanism for rotating said transfer roller; a paste storage unit for storing paste to be supplied to the surface of said transfer roller; a squeegee having a distal edge parallel to a rotary shaft of said transfer roller, and being located with a gap between the surface of said transfer roller and the distal edge; a squeegee holder comprising a leaf spring that has one end fixed to said sub frame and the other end oscillatable, and that is folded so as to have a U-shaped cross section and a movable piece whose cross section is L-shaped, and where the squeegee is mounted at one end and the other end is secured to the other end of the leaf spring and it forms a cantilever using the leaf spring as a supporting point; and supporting said squeegee while urging said squeegee in one of either a direction to extend the gap or a direction to reduce the gap; a gap adjustment mechanism comprising a screw fitted to said sub frame and an elevating member projecting from a head of the screw and contacting said movable piece, and impelling said squeegee to the direction to narrow the gap down; a slide mechanism to move said sub frame to a perpendicular direction with regard to the rotary shaft of said transfer roller; and a controller for controlling at least one of said roller drive mechanism and said slide mechanism, so that a tangential velocity at the surface of said transfer roller is lower than a movement velocity of said sub frame.