Optimized lithography and etching processes for a magnetic oxide micro-device

A new process based on thick novolak UV resists is proposed for elaborating a Mott field effect transistor (FET) based on "ferroelectric/manganite" heterostructures. The whole process of this micro-device, which is a succession of photo-lithography, dry etching (IBE and RIE) and metal deposition steps, has been optimized and devices with vertical gate lengths as small as 5 μm have been successfully patterned. Special care was taken to prevent interference phenomena during UV lithography.