Photolithographic Mask Fabrication Process Using Cr/Sapphire Carriers

Abstract

Elaboration of the technology of novel photolithographic masks fabricated on sapphire substrates for UV and DUV application was described. The main technological steps of mask fabrication as Cr metallization deposition, selection of resist for lithography and Cr layer etching were developed and reported. The etching of Cr films was carried out through resist mask. Detailed study of Cr layer etching process was performed using different solutions such as KMnO4, HCl and ceric ammonium nitrate-based solutions to obtain good-quality structures with the smallest possible undercut of Cr layer and smooth edge. The mask fabrication process was validated by fabrication of test structures of microelectronic device using photolithography technique.