title: Micro/nano scale amorphization of silicon by femtosecond laser irradiation.
abstract: This research aimed to investigate the feasibility of using direct amorphization of silicon induced by femtosecond laser irradiation for maskless lithography. A thin layer of amorphous silicon of predetermined pattern was first generated by irradiation by a femtosecond laser of Mega Hertz pulse frequency. The following KOH etching revealed that the amorphous silicon layer acted as an etch stop. Line width less than 1/67 the focused spot size was demonstrated and hence the proposed maskless lithography process has the potential of producing submicron and nanoscale features by employing a laser beam of shorter wavelength and a high NA focusing lens. Scanning Electron Microscope (SEM), a Micro-Raman and Energy Dispersive X-ray (EDX) spectroscopy analyses were used to evaluate the quality of amorphous layer and the etching process.
authors.affiliation: Department of Mechanical and Industrial Engineering, Ryerson University, 350 Victoria Street, Toronto, ON, Canada M5B 2K3.
authors.forename: Amirkianoosh
authors.initials: A
authors.lastname: Kiani
authors.forename: Krishnan
authors.initials: K
authors.lastname: Venkatakrishnan
authors.forename: Bo
authors.initials: B
authors.lastname: Tan