Abstract: A transformer element 1 is formed on a semiconductor substrate using first and second wiring layers arranged parallel to each other in a vertical direction, and includes a first inductor 2 and a second inductor 3. The first and second inductors 2 and 3 are each provided using the first and second wiring layers such that if projected into one of the first and second wiring layers either along a vertical upward direction or a vertical downward direction, outlines of a projection form a symmetrical shape with respect to a predetermined reference plane, and portions corresponding to intersections between the outlines of the projection on the wiring layer are formed so as to be out of contact with each other.

Abstract: A fluorine-containing alkylsuccinic acid diester of the formula: ##STR1## wherein R.sub.1 is an aliphatic alkyl or alkenyl group, and one of R.sub.2 and R.sub.3 is a fluoroalkylether group and the other is a fluoroalkyl group, a fluoroalkenyl group, a fluorophenyl group, an aliphatic alkyl group or-an aliphatic alkenyl group, which has excellent lubricity in an atmosphere having low to high humidity.