The present application relates to a semiconductor structure and a method of forming the same.  More particularly, the present application relates to a high density vertical resistor structure that is embedded in a dielectric material and is located between different interconnect levels.  The present application also provides a method of forming such a semiconductor structure. 
A resistor, which is a passive two-terminal electrical component that implements electrical resistance as a circuit element, is one of the most common electrical components present in almost every electrical device.  In electronic circuits, resistors can be used to limit current flow, to adjust signal levels, bias active elements, and terminate transition lines. 
Resistors are needed in back-end-of-the-line (BEOL) interconnect technology to balance overall RC loads and improve circuit performance.  Typical resistors for BEOL interconnect levels include expanded, planar resistors which occupy a large amount of real estate at high cost.  As device dimensions continue to scale down, there is an ever increasing need for resistivity control of the resistor materials employed. 
There is thus a need for embedded resistors in BEOL technology which occupy a significant reduced area on the chip, while allowing tunable resistance values.