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Exotic material properties and topological nontrivial surface states have been theoretically predicted to emerge in [111]-oriented perovskite layers. The realization of such [111]-oriented perovskite superlattices has been found challenging, and even the growth of perovskite oxide films along this crystallographic direction has been proven as a formidable task, attributed to the highly polar character of the perovskite (111) surface. Successful epitaxial growth along this direction has so far been limited to thin film deposition techniques involving a relatively high kinetic energy, specifically pulsed laser deposition and sputtering. Here, we report on the self-regulated growth of [111]-oriented high-quality SrVO3 by hybrid molecular beam epitaxy. The favorable growth kinetics available for the growth of perovskite oxides by hybrid molecular beam epitaxy on non-polar surfaces was also present for the growth of [111]-oriented films, resulting in high-quality SrVO3(111) thin films with residual resistivity ratios exceeding 20. The ability to grow high-quality perovskite oxides along energetically unfavorable crystallographic directions using hybrid molecular beam epitaxy opens up opportunities to study the transport properties of topological nontrivial and correlated electron systems.
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This content will become publicly available on December 1, 2026
Effect of inert gas background pressure on resonant infrared matrix-assisted pulsed laser evaporation deposition of two-dimensional hybrid perovskite
Hybrid perovskite materials have emerged as excellent candidates for next-generation optoelectronic applications. Nevertheless, many vapor deposition techniques face challenges like phase segregation, thermal decomposition, and nonstoichiometric film growth. Resonant infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE) addresses these challenges by eliminating thermal stability concerns for precursor materials while maintaining stoichiometry and producing high-quality film growth. Despite its advantages, scaling up RIR-MAPLE remains underexplored compared to conventional techniques. A main challenge is to ensure high throughput with precise control over film properties. RIR-MAPLE films are typically grown under an active vacuum (chamber pressure of ∼10−5 Torr). Film deposition under background gas pressure has not been investigated, leaving questions about how an inert gas environment could influence material properties. Thus, understanding film deposition in a reduced vacuum environment with background inert gas, such as nitrogen gas, is crucial to demonstrate the feasibility of higher throughput to achieve industrial scalability. This study examines the effect of nitrogen background pressure on the deposition of two-dimensional hybrid perovskite films, namely, phenethylammonium lead iodide revealing significant improvements in film crystallinity, optical properties, and defect density with increasing background pressure, thereby highlighting the potential for scaling RIR-MAPLE for the synthesis of high-performance hybrid perovskite films.
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- Award ID(s):
- 2227551
- PAR ID:
- 10655935
- Publisher / Repository:
- AIP Publishing
- Date Published:
- Journal Name:
- Journal of Vacuum Science & Technology A
- Volume:
- 43
- Issue:
- 6
- ISSN:
- 0734-2101
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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