Epitaxial Oxides on Semiconductors: From Fundamentals to New Devices

Abstract

Functional oxides are an untapped resource for futuristic devices and functionalities. These functionalities can range from high temperature superconductivity to multiferroicity and novel catalytic schemes. The most prominent route for transforming these ideas from a single device in the lab to practical technologies is by integration with semiconductors. Moreover, coupling oxides with semiconductors can herald new and unexpected functionalities that exist in neither of the individual materials. Therefore, oxide epitaxy on semiconductors provides a materials platform for novel device technologies. As oxides and semiconductors exhibit properties that are complementary to one another, epitaxial heterostructures comprised of the two are uniquely poised to deliver rich functionalities. This review discusses recent advancements in the growth of epitaxial oxides on semiconductors, and the electronic and physical structure of their interfaces. Leaning on these fundamentals and practicalities, the material behavior and functionality of semiconductor-oxide heterostructures is discussed, and their potential as device building blocks is highlighted. The culmination of this discussion is a review of recent advances in the development of prototype devices based on semiconductor-oxide heterostructures, in areas ranging from silicon photonics to photocatalysis. This overview is intended to stimulate ideas for new concepts of functional devices and lay the groundwork for their realization.

Domain matching epitaxy stabilized metastable, tetragonal BiFeO3 on symmetry-mismatched c-plane ZnO

“…Most of the elongated islands in Fig. 2(b) are oriented along three equivalent ZnO [11][12][13][14][15][16][17][18][19][20] directions, consistent with the domain schematically shown in Fig. 1(e).…”

Epitaxial Growth of Cobalt Oxide Thin Films on Sapphire Substrates Using Atmospheric Pressure Mist Chemical Vapor Deposition

“…Therefore, the annealing temperature of 650 °C, The electrical properties of CoO films were evaluated using the Hall-effect measurement. The electrical resistivities of the as-grown CoO and Co 3 O 4 films were 1.8 × 10 5 Ω-cm and 2.3 × 10 2 Ω-cm, respectively, which are consistent with the values reported by other studies (>10 4 Ohm cm for CoO; 1~10 3 Ohm cm for Co 3 O 4 ) [22]. Based on the results reported by previous studies, the electrical performance of various metal-oxide semiconductor films can be further improved via annealing at the temperature higher than that used in the film growth process [43,44].…”

Metastable Tetragonal BiFeO3 Stabilized on Anisotropic a-Plane ZnO

“…Owing to the chemical compatibility between T-BFO and ZnO, a sharp interface with a negligible interdiffusion layer was observed, suggesting a high-quality interfacial growth of T-BFO. By contrast, the growths of ABO 3 oxides on group IV and III–V semiconductors all generate remarkable interfacial reaction layers . The lattice spacings of T-BFO(110) and ZnO­(1-100) facets are determined to be 2.664 and 2.813 Å, respectively.…”

“…By contrast, the growths of ABO 3 oxides on group IV and III−V semiconductors all generate remarkable interfacial reaction layers. 33 The lattice spacings of T-BFO(110) and ZnO(1-100) facets are determined to be 2.664 and 2.813 Å, respectively. Accordingly, the lattice mismatch (f) between T-BFO and ZnO along ZnO[1-100] is estimated to be −5.3%.…”