A structure for resistors and the method for tuning the same. The resistor
comprises an electrically conducting region coupled to a liner region.
Both the electrically conducting region and the liner region are
electrically coupled to first and second contact regions. A voltage
difference is applied between the first and second contact regions. As a
result, a current flows between the first and second contact regions in
the electrically conducting region. The voltage difference and the
materials of the electrically conducting region and the liner region are
such that electromigration occurs only in the electrically conducting
region. As a result, a void region within the electrically conducting
region expands in the direction of the flow of the charged particles
constituting the current. Because the resistor loses a conducting portion
of the electrically conducting region to the void region, the resistance
of the resistor is increased (i.e., tuned).