Dynamic maskless holographic lithography and applications

The purpose of this research is to improve the resolution of dynamic maskless holographic lithography (DMHL) by using two-photon absorption, to provide a more thorough characterization of the process, and to expand the functionality of the process by adding previously undemonstrated patterning modes. Two-photon DMHL will be performed in both 2D and 3D configurations with specific characterization relating to process resolution and repeatability. The physical limits of DMHL will be discussed and ways to circumvent them will be proposed and tested.;DMHL eliminates the need for a separate mask for every different pattern exposure and allows for real-time shaping of the exposure pattern. It uses an electrically addressable spatial light modulator (SLM) to create an arbitrary intensity pattern at the specimen plane. The SLM is a phase mask that displays a hologram. An algorithm is used to find an appropriate phase hologram for each desired intensity pattern. Each pixel of the SLM shapes the wavefront of the incoming laser light so that the natural Fourier transforming property of a lens causes the desired image to appear in the specimen plane. The process enables one-off projects to be done without the cost of fabricating a mask, and makes it possible to perform lithography with fewer (or even no) moving parts.