High density connector having a ball type of contact surface

An electrical connector (1) for use with a circuit substrate has a spacer member (10) and a plurality of elongated conductors (8). The conductors are fitted into passages (25) on the spacer member (10). A tail end of each conductor terminates in a well (11) on a surface of the spacer member that facilitates the attachment of the electrical connector to the substrate. The passages in the spacer member hold the conductor tail ends in alignment while providing a clearance around the conductors to accommodate the effects of thermal expansion and contraction. Solder paste (19) from the well (11) with or without a preformed solder ball (12) is coalesced into a spherical shaped conductive body at least partially extending outside said well for connection between the conductors and the circuit substrate. A spherical shaped conductor body is fused to the end of the conductors (8).