A strategy for fabricating micro-scale freestanding single-crystalline complex oxide device arrays

Huandong Chen; Yang Liu; Harish Kumarasubramanian; Mythili Surendran; Jayakanth Ravichandran

doi:10.1021/acsaelm.4c01480

paper

A strategy for fabricating micro-scale freestanding single-crystalline complex oxide device arrays

arXiv:2408.10071 · doi:10.1021/acsaelm.4c01480

Abstract

We present a general fabrication strategy for freestanding single-crystalline complex oxide device arrays via wet chemical etching-based microfabrication processes and epitaxial lift-off. Here, we used 0.5Ba(Zr $_{0.2}$ Ti $_{0.8}$ )O $_{3}$ -0.5Ba(Zr $_{0.7}$ Ti $_{0.3}$ )O $_{3}$ (BCZT) as a model relaxor ferroelectric oxide system and La $_{0.7}$ Sr $_{0.3}$ MnO $_{3}$ as the sacrificial layer for demonstration. Arrays of SrRuO $_{3}$ (SRO) / BCZT / SRO ferroelectric capacitor mesas were first defined and isolated on the growth wafer, and then they were released using epitaxial lift-off with lithography-defined surrounding etching holes, after which the freestanding device arrays were integrated onto a glass substrate. Our proposed strategy sheds light on preparing various freestanding single-crystalline oxide devices and paves the way for their heterogeneous integration onto arbitrary substates.