Maskless Lithography Beyond EUV Using Transmissive Diffractive Microlenses

The high-flux free-electron lasers being developed for EUV can also deliver a better wavelength for lithography, i.e., 4.5 nm.  This change, together with diffractive microlenses in a maskless lithography scheme, called X-ZPAL, will outperform EUV and lower the cost of semiconductor manufacturing. The elements X-ZPAL will be described along with the innovations resulting from its adoption. 

Henry I. Smith is Emeritus Professor at MIT. He, his students and co-workers have contributed a number of innovations to nanoscale science and engineering, including:  x-ray lithography, the attenuating phase-shift mask, achromatic-interference lithography, zone-plate-array lithography, interferometric mask alignment and graphoepitaxy.