Two-Dimensional Phase-Shift Control In Laser Interference Patterns

Nanotechnology is a key technology in today’s world, and it has been successfully used in many areas such as medicine, pharmacy and biological detection. Nanolithography, as the core of nanotechnology, has very important application prospects. In a variety of nanolithography technologies, laser interference nanolithography has its advantage of low cost. In order to improve the resolution of the laser interference pattern, ensure the quality of the interference pattern and obtain a large area of the interference pattern, precise control of phase-shift laser interference must be done in nanolithography.In this report, two-dimensional phase-shift control and disturbance compensation of the laser interference pattern are achieved by controlling the nano displacement in a laser interference system. Nano displacement is introduced by a PZT mirror stage driven with a high resolution D/A converter and a precision voltage source. When different voltages are applied to PZT, it will move mirror forward or backward, and the precise detection and control of the phase-shift of the interference pattern are achieved by changing the optical path length difference.