Process development and monitoring with atomic force profiling for CMP

CMP processes are being used in an increasing number of applications in the wafer fab in response to shrinking device geometries with their increased need for planarity. There is a corresponding growing need for measurement o f post-CMP parameters over lengths from device size (<1 mu m) to die size ( >10mm). Measurements required for process development and production monito ring include plug recess, dishing around lines and plugs, erosion in patter ned areas and planarity across the die. A new instrument, combining capabil ities of stylus surface profilers and atomic force microscopes, has been de veloped specifically for this purpose.