“Enabling Atomic Layer Etching of Magnetic and Noble Metals”
The demand for a universal memory grows each year, driven by the desire for increased storage density with better device performance. As the critical dimension of the memory nanostructures continues to shrink and new materials are introduced, additional patterning techniques and chemistries must be developed to overcome the challenges in materials processing. The ability to selectively and directionally control material removal at an atomic level allows for the further advancement of memory technologies.
My work focuses on utilizing plasma processing to control the removal and manipulate the chemical states of hard-to-etch metallic and intermetallic films such as Co, Pt and CoFeB, which are essential for magnetic memories. Sequential exposure of chlorine and hydrogen discharges were studied to enable enhanced etch rates of elemental and metal alloy thin films by up to 40% while preserving both the thin film stoichiometry and critical magnetic properties. In addition, alternating cycles of oxygen plasma in conjunction with organic vapor were investigated to facilitate etch rates down to 0.5 nm/cycle. Plasma oxidation created the necessary chemical contrast for selective material removal during the subsequent organic chemical vapor etch. Furthermore, ions present in the discharge enabled directionality in nano-scale patterning of the aforementioned hard-to-etch materials necessary for implementing next generation memories.
Date/Time:
Date(s) - May 04, 2018
10:00 am - 11:00 am
Location:
Boelter Hall 3400
420 Westwood Plaza Los Angeles CA 90095