Progress and Preliminary Results on EB Stepper

Abstract

The EB stepper is an electron beam projection lithography (EPL) system. The EB stepper system is similar to an optical scanning exposure system with a reticle. Nikon has been developing EB stepper on the basis of the optical stepper design. The field size of the electron optical (EO) subsystem of EB stepper (subfield/(SF)) is 1 mm square on a reticle and 250 µm square on a wafer (demagnification: 4×). For full chip exposure, SF exposures are stitched using electron beam deflection and stage movement. A new type of stage has been developed for EB stepper using air guides and linear motors to achieve a high-throughput target. These subsystems are assembled separately at present. In this paper, preliminary results on EB stepper as an exposure system are reported. Progress on infrastructures for EPL is discussed.

Highly Reliable Piezoelectric Actuator for Precision Stage System

“…The feature size of current electronic circuits has become the same as ultraviolet wavelengths in the range of 0.1 mm due to the use of shorter wavelength light sources such as a F 2 laser. An electron beam (EB) should be adopted as the primary exposure source and it may be widely used in applications such as the exposure system for mask fabrication, 1) and critical-dimension scanning electron microscopes (CD-SEM) for pattern inspection. One of the core technologies supporting such manufacturing equipment is the ultra-precision stage, which enables the target to be moved accurately and quickly.…”

Slip-Free Driving Method for Nonresonant Piezoelectric Actuator

“…Magnetic-noise elimination, small footprint, or simplified control-operation would be necessary, either. 3) Piezoelectric actuators employing the DC piezoelectric effect have extremely high resolution, but their stroke is very small. [4][5][6] The inchworm positioner, for instance, attains a high positioning accuracy and a long stroke simultaneously, but the feeding velocity is limited to several mm/s and the feeding motion is intermittent and discontinuous.…”