Unit of area in RTL Compiler
The answers from Cadence forum:

If your library says the are of a buffer is 10 square units and your design has 2 buffers, RC should report an area of 20. A few things to keep in mind:


most libraries use square microns for units but some use their own reference unit which may or may not be documented in library
RC report cell area as well as area. area includes cell area and an estimate of net area. As mentioned before, the cell area is not estimated whereas net is.


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