Sub-micron circuit fabrication on diamond anvils for mesoscopic high-pressure experiments

Abstract

We present a fabrication procedure to produce high-quality liftoff structures on diamond anvils that extend continuously from the culet onto the slanted facets. Feature sizes as small as 500 nm are achieved using a trilayer resist stack and electron beam lithography. Device structures with strong adhesion to the diamond surface and high abrasion resistance are realized by optimizing the surface treatment. To benchmark our process, we fabricate a multi-lead tungsten circuit to measure changes in the superconducting transition temperature of zirconium across the structural phase transition at ∼30 GPa, revealing a nearly fourfold increase in the critical temperature. Our process is reproducible in most traditional academic and industrial cleanroom facilities. This method enables reproducible, high-resolution circuit fabrication on diamond anvils and other faceted crystalline substrates.