High‐performance synchrotron orbital radiation x‐ray stepper Available to Purchase

A newly designed synchrotron orbital radiation x‐ray stepper system has been developed to establish practical quarter‐micrometer x‐ray lithography and installed in the Tsukuba Research Laboratory for SORTEC Corporation, Japan. This stepper features the newly devised high‐precision real‐time full‐closed alignment system and the ultraprecision vertical wafer stage which can be operated at an atmospheric helium pressure. In order to realize precision positioning of the wafer stage, we developed a 10‐axis stage by combining a coarse XY positioning stage guided by hydrostatic air bearings and a fine positioning stage driven by six piezoelectric actuators. We also developed holographic alignment error detection optics, which consists of a three‐axis Fourier transform lens system. Alignment error between the mask and the wafer can be detected during exposure and is fed back to the servo control system. By this real‐time alignment error correction, an alignment precision of 0.06 μm(3σ) was successfully achieved.