Precision measurement of X-axis stage mirror profile in scanning beam interference lithography by three-probe system based on bidirectional integration model

A profile of an X-axis stage mirror results in a phase error of gratings in Scanning Beam Interference Lithography. Traditional methods of measuring the profile require extra probes and another large stage mirror on Y-axis, or requires other operations such as rotating measured object to adjust the zero-adjustment errors. This paper introduces a three-probe system removing the need for Y-axis optical path structure and proposes a bidirectional integration model to solve the problem of zero-adjustment error, simplifying the optical path structure and the measurement process. This method is confirmed by theoretical analysis and experimental results, which is better than traditional methods and can also be used in other application fields of three-point method.