Epitaxial Ba0.5Sr0.5TiO3–GaN heterostructures with abrupt interfaces

Losego, Mark D.; Kourkoutis, Lena F.; Mita, Seiji; Craft, H. S.; Muller, David A.; Collazo, Ramón; Sitar, Zlatko; Maria, Jon Paul

doi:10.1016/j.jcrysgro.2008.11.085

Cited by 17 publications

(7 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Deposition in water vapour reduces the FWHM values in φ by a factor of two compared with deposition in oxygen, from 3.7° to 1.6°. Though substantial, these line widths are consistent with the 7% lattice mismatch at this oxide-nitride interface and compare favourably to reports of cubic oxide epitaxy on GaN, particularly with respect to in-plane crystallinity 6,12,25,26 . We note that a low-resolution x-ray diffraction configuration was used (crossed beam collimator and receiving slits) to maximize intensity as the films are 25 nm thick.…”

Section: Film Characterizationsupporting

confidence: 88%

See 1 more Smart Citation

Surfactant-enabled epitaxy through control of growth mode with chemical boundary conditions

et al. 2011

View full text Add to dashboard Cite

Property coupling at interfaces between active materials is a rich source of functionality, if defect densities are low, interfaces are smooth and the microstructure is featureless. Conventional synthesis techniques generally fail to achieve this when materials have highly dissimilar structure, symmetry and bond type-precisely when the potential for property engineering is most pronounced. Here we present a general synthesis methodology, involving systematic control of the chemical boundary conditions in situ, by which the crystal habit, and thus growth mode, can be actively engineered. In so doing, we establish the capability for layer-by-layer deposition in systems that otherwise default to island formation and grainy morphology. This technique is demonstrated via atomically smooth {111} calcium oxide films on (0001) gallium nitride. The operative surfactant-based mechanism is verified by temperature-dependent predictions from ab initio thermodynamic calculations. Calcium oxide films with smooth morphology exhibit a three order of magnitude enhancement of insulation resistance.

show abstract

Section: Film Characterizationsupporting

confidence: 88%

“…With conventional growth techniques, at only several monolayers thickness, rocksalt films collapse into pyramidal islands with {100} faces [9][10][11] . This seemingly unavoidable behaviour leads to a grainy morphology and diminished functionality 12,13 . The surfactant-assisted method applied currently to CaO can be extended to more complicated systems.…”

mentioning

confidence: 99%

Surfactant-enabled epitaxy through control of growth mode with chemical boundary conditions

et al. 2011

View full text Add to dashboard Cite

show abstract

“…In addition to a thorough investigation of the structure, this work further addresses important practical aspects of ferroelectric behavior, including material fatigue (exhibiting 10.2% degradation after 1.1 × 10 10 cycles), and leakage (<2 μA cm −2 ). Alternative integration approaches were attempted by PLD and RF magnetron sputtering of ferroelectric Ba 0.5 Sr 0.5 TiO 3 directly on GaN without buffer layers, which resulted in films that exhibited domain structures.…”

Section: Materials and Functional Propertiesmentioning

confidence: 99%

Epitaxial Oxides on Semiconductors: From Fundamentals to New Devices

Kumah

Ngai

Kornblum

2019

Adv Funct Materials

View full text Add to dashboard Cite

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.

show abstract

“…Devices such as heterojunction bipolar transistors, quantum well lasers and heterojunction field effect transistors (FET), already have a significant technological impact. The semiconductor-ferroelectric heterostructures have attracted much attention due to their large potential for electronic and optoelectronic device applications (Lorentz et al, 2007;Losego et al, 2009;Mbenkum et al, 2005;Voora et al, 2009;. The ferroelectric constituent possesses switchable dielectric polarization, which can be exploited for modificating the electronic and optical properties of a semiconductor heterostructure.…”

mentioning

confidence: 99%

“…Thus, it is interesting to grow high quality wurtzite ZnO and InN films on perovskite STO substrates, and it is useful to determine the valence band offset (VBO) of these heterojunctions. The heterojunction of semiconductor-ZnO or InN/ferroelectric-BaTiO 3 (BTO) provides an interesting optoelectronic application due to the anticipated strong polarization coupling between the fixed semiconductor dipole and the switchable ferroelectric dipole (Lorentz et al, 2007;Losego et al, 2009;Mbenkum et al, 2005;Voora et al, 2009;. ZnO TFT, highly attractive for display applications due to transparency in the visible and low growth temperatures, are limited by large threshold and operating voltages (Kim et al, 2005).…”

mentioning

confidence: 99%