a method for controlling the height , shape and placement of solder connections of a surface mount circuit device , such as a flip chip , by way of controlling the extent to which solder is able to flow on a conductor during reflow , but without the conventional use of a solder mask in a manner that results in a portion of the mask remaining beneath the device . each conductor is defined to include a bond pad and a reduced - width portion adjacent the bond pad . the width of each reduced - width portion is sufficiently narrower than the width of its adjacent bond pad to impede the flow of molten solder onto the reduced - width portion from a solder bump registered with the bond pad . as a result , when reflow soldering a circuit device to the circuit board , molten solder substantially remains on the bond pads and , for a given solder bump size , the bond pads determine the shape and height of the resulting solder connections .