Heterogeneous integration of single-crystalline complex-oxide membranes

Dielectric films for high performance capacitive energy storage: multiscale engineering

“…Success for flexible energy-storage films has been proven using modified deposition on flexible substrates, 85,86 which might also be possible using lift-off techniques. 87,88…”

High-performance freestanding thermoelectric membrane by intact exfoliation of van der Waals epitaxial bismuth antimony telluride film

“…Thermoelectric Bi 2 Te 3 -based thin lms have been achieved by the conventional heterogeneous epitaxial growth on single crystalline substrates with a small lattice mismatch and atomically at surface 17,18 , which suppress the formation of structural and atomic defects. However, this heterogenous epitaxial thin lm growth limits the applications to the curved and exible thermoelectrics due to the clamping effect, inherited from strong bond between overlayer lm and substrate at interface, of epitaxial thin lms on the at substrate 19,20 . Furthermore, it is extremely di cult to grow high quality epitaxial thin lms on the materials with large lattice mismatch or on the exible matters 21 .…”

“…Indeed, the layer structured Bi 0.5 Sb 1.5 Te 3 (BST) alloy, which are widespread p-type material for room temperature refrigeration and power generation, has been successfully grown via the vdWE on the graphene transferred amorphous silica substrate and on the pseudomorphic Te monolayer at the surface of sapphire substrate, showing comparable electrical properties to single crystal BST alloy. Considering the previous lift-off techniques for freestanding complex-oxide membranes 20 , this vdWE BST thin lm, which has a weak bonding at the vdW hetero-interface between Te-terminated quintuple layer and pseudomorphic Te monolayer on sapphire substrate, has a potential for intact exfoliation and direct transfer on curved or exible supports for freestanding thermoelectric membranes. The naturally-formed pseudomorphic Te monolayer on the sapphire substrate during in-situ spontaneous vdWE growth is of bene t in practical lift-off process in chemical solution, working as a sacri cial layer.…”

A platform for making and transferring oxide films

“…In the past few years, free-standing membranes of certain oxides have been made 4,5 by removing epitaxial films from substrates using a process dubbed chemical lift-off. Now, on page 75, Kum et al 6 report a versatile method for producing a wide variety of complex-oxide films that can be easily transferred to any material.…”

“…The film could then be exfoliated from the strontium ruthenate by depositing a layer of nickel on top of the film. The nickel acts as a stressor -it provides 6 report a versatile approach for making high-quality films of technologically useful compounds called complex oxides and transferring these films to other materials. As a demonstration, the authors grew a film of the complex oxide cobalt ferrite using a technique known as remote epitaxy, whereby the film and the underlying substrate are separated by a few sheets of the material graphene.…”