An umbilical has a center tube that is a steel tube, and that the cross section of the center tube at the extremity of the umbilical is made corrugated on a length that extends substantially from the extremity to a distance from the extremity so that fatigue strain on non corrugated parts of the steel tube is avoided when the extremity of the umbilical is inserted into a bend stiffener. The clip is delivered to the location in a collapsed stated and is released from a sheath convert to an undeflected or relaxed state. A plurality of cell plugs are formed adjacent to side surfaces of the bit lines. The dicing tape that is affixed to the semiconductor wafer is held by a holding jig. Also described are a microprocessor having an ALU incorporating one or more of the adder circuits, as well as a method of adding two numbers which generates differential sum and sum-complement outputs but does not use full-differential domino circuits, thus providing considerable savings in circuit area, circuit conductors, and layout complexity.