Frontiers in the Growth of Complex Oxide Thin Films: Past, Present, and Future of Hybrid MBE

Abstract

Driven by an ever-expanding interest in new material systems with new functionality, the growth of atomic-scale electronic materials by molecular beam epitaxy (MBE) has evolved continuously since the 1950s. Here, a new MBE technique called hybrid-MBE (hMBE) is reviewed that has been proven a powerful approach for tackling the challenge of growing high-quality, multicomponent complex oxides, specifically the ABO 3 perovskites. The goal of this work is to (1) discuss the development of hMBE in a historical context, (2) review the advantageous surface kinetics and chemistry that enable the self-regulated growth of ABO 3 perovskites, (3) layout the key components and technical challenges associated with hMBE, (4) review the status of the field and the materials that have been successfully grown by hMBE which demonstrate its general applicability, and (5) discuss the future of hMBE in regards to technical innovations and expansion into new material classes, which are aimed at expanding into industrial realm and at tackling new scientific endeavors.

Epitaxial Oxides on Semiconductors: From Fundamentals to New Devices

“…Increasing the scalability and throughput of epitaxial growth on semiconductors should be an important objective to extend pathways to practical integration. Efforts to grow epitaxial oxides on semiconductors via ALD and hybrid MBE have shown great promise. Continued effort should be focused on improving the quality of epitaxial films and interfaces grown using these techniques.…”

“…Zhang and coworkers have explored the hybrid MBE (hMBE) growth method to fabricate stoichiometric STO films on Si with scalable growth rates on the order of 1 nm min −1 . The hMBE technique has been thoroughly detailed in a recent review . Sr is evaporated from an elemental thermal source and Ti and O are obtained from the alkaloid precursor titanium tetraisopropoxide (TTIP).…”

Surface Characterizations and Selective Etching of Sr‐Rich Segregation on Top of SrVO3 Thin‐Films Grown by Pulsed Laser Deposition

“…An optimized and competitive SrVO 3 (SVO) thin‐film is characterized by two factors, a stoichiometric cationic ratio Sr/V equal to 1 and a high relative resistivity ratio (RRR) which is the ratio of electrical resistivity at room temperature (300 K) and the one at low temperature (2 K). State of the art SVO thin‐films grown by pulsed laser deposition (PLD) onto SrTiO 3 (STO) (100) have a RRR of 2.4, which is much lower compared to hybrid‐MBE deposition technique ,. Since PLD is a most common technique for complex oxides, process conditions to perform an efficient SVO thin‐film are taken under strong interest ,,.…”

“…State of the art SVO thin-films grown by pulsed laser deposition (PLD) onto SrTiO 3 (STO) (100) have a RRR of 2.4, [10] which is much lower compared to hybrid-MBE deposition technique. [9,[20][21][22] Since PLD is a most common technique for complex oxides, [23][24][25] process conditions to perform an efficient SVO thin-film are taken under strong interest. [6,26,27] In this regard, oxygen is particularly known as a crucial parameter leading for instance to the creation of a Metal Insulator Transition (MIT) in other perovskite compounds for STO, [28][29][30] and LaNiO 3 .…”

Observation of Crystalline Oxidized Silicon Phase

“…The crystalline phase for the widely used and studied SiO x /Si system has been discovered by controlling the oxidation of clean Si in vacuum conditions. The found material provides a novel well‐defined platform for both the fundamental studies and the engineering of the bandgap area by controlling the defect‐level density and internal electric field in applications, supporting use of vacuum‐based technology in the materials engineering . Role of atomic‐scale control of the SiO x /Si properties is expected to increase further when the size of SiO x /Si building blocks in various applications decreases continuously.…”