Statistical Models for Estimating the Measurement of Pitch in Metrology Instruments
Nien F. Zhang, Michael T. Postek, Robert D. Larrabee
The measurement of pitch in metrology instruments is through to be a benign self-compensating function. In the course of issuing the new scanning electron microscope standard SRM 2090, a new algorithm for the measurement of pitch was developed. This is based on linear regression models. For a pitch measurement, a regression line is traditionally fitted to each edge of the data independently, then the distance between some arbitrary threshold on that line is determined. The new algorithm eliminates the need for a threshold. An evaluation of uncertainty of the measurement process is also described.