Does your SEM really tell the truth?

The scanning electron microscope (SEM) has gone through a tremendous evolution to become a critical tool for many, diverse scientifi c and industrial applications. The high resolution of the SEM is especially useful for qualitative and quantitative applications for both nanotechnology and nanomanufacturing. It is likely that one of the fi rst questions asked when the fi rst scanning electron micrograph was ever taken was: "...how big is that?" The quality of that answer has improved a great deal over the past few years, especially since SEMs are being used as a primary tool on semiconductor processing lines to monitor the manufacturing processes. The needs of semiconductor production prompted a rapid evolution of the instrument and its capabilities. Over the past 20 years or so, instrument manufacturers, through this substantial semiconductor industry investment of research and development (R&D) money, have vastly improved the performance of these instruments. All users have benefi tted from this investment, especially where metrology with an SEM is concerned. But, how good are these data? This presentation will discuss a sub-set of the most important aspects and larger issues associated with imaging and metrology with the SEM. Every user should know, and understand these issues before any critical quantitative work is attempted.