Photoconductivity of CaH₂-reduced BaSnO₃ thin films

Abstract

Incorporation of foreign chemical elements in oxides can significantly alter their optoelectronic performances, and thus it is widely used to seek new transparent conductive oxides. Chemical-doping BaSnO 3 systems, like La-doped BaSnO 3 , are of increasing interest with extremely high electrical mobility and excellent oxygen stability, exhibiting the potential application in next-generation all-perovskite optoelectronic devices. In this work, hydrogen was introduced into BaSnO 3 through CaH 2 reduction of BaSnO 3 thin films, and the electrical properties, as well as the photo-response behavior, were investigated. Secondary ion mass spectroscopy demonstrated the uniform distribution of hydrogen within the BaSnO 3 thin film. The addition of hydrogen greatly enhanced the conductivity of the BaSnO 3 thin film, exhibiting a carrier concentration $8.04 Â 10 19 cm À3 and mobility $9.52 cm 2 V À1 s À1 at 300 K, and thus resulted in a fast relaxation process in the transient photoconductivity, which was characterized by a double exponential function indicating two physical contributions.

Unraveling the Oxygen Effect on the Properties of Sputtered BaSnO3 Thin Films

“…From the best peak deconvolution, one can see two spectral components, centered at around 529.4 ± 0.2 and 531.0 ± 0.1 eV, respectively. The first spectral component, located at the low binding energy (∼529.4 eV), is ascribed to the lattice oxygen (O L ) in BSO-based compounds, while the second component is related to the oxygen vacancies (O V ). , The ratio of peak areas (O V /O L ), which is positively correlated with the relative concentration of oxygen vacancies, is presented in Figure d, confirming that the number of oxygen vacancies increases with a decrease in oxygen partial pressure. To meet the requirement of charge neutrality, it is reasonably believed that the Sn 2+ ions should exist in oxygen-deficient BSO films .…”

“…The wavelength scanning regime is between 300 and 700 nm. More measurement details can be found in prior work …”

Oxygen vacancy-assisted recovery process for increasing electron mobility in n-type BaSnO3 epitaxial thin films

“…S5a) 26,27 , so hydrogen interstitials are unlikely to be the main origin of mobile carriers. Instead, deconvolution of the O 1s XPS spectra of both films indicates that the areal ratio of the O(II) peak (~531.6 eV) to the O(I) peak (~530.1 eV), which are related to oxygen vacancies and lattice oxygens 23 , respectively, increased from 0.588 in as-grown BSO to 1.42 in the 5% H 2 BSO films (Fig. S5b, c); this result reveals the formation of oxygen vacancies, which can be additional sources of mobile electrons in the LBSO films after H 2 treatment.…”

“…The increase in n under a reducing atmosphere may be related to the introduction of carrier-generating point defects such as oxygen vacancies or interstitial hydrogen [22][23][24] . Treatment under excessively reducing conditions at high temperature (i.e., 5% H 2 at 950°C) to increase the diffusivity of the point defects led to a significant suppression of the (001) XRD peak and insulating properties of the LBSO epitaxial films; these changes can be attributed to the collapse of the BSO crystal structure due to excessive formation (or incorporation) of oxygen vacancies in BSO (Fig.…”

Magnetically Tunable Photocurrent in La0.7Sr0.3MnO3/BaSnO3 Heterojunctions

“…Under illuminated condition, a Xenon lamp coupled into a grating monochromator (Oriel Cornerstone 260) was used for the light source, and the photocurrent data were collected by a 6487 Keithley electrometer, as described previously in Ref. . Under magnetic condition, the magnetic field was applied parallel to the surface of LSMO/BSO heterojunction, and the light source is the laser diodes (≈10 mW cm −2 ) with different wavelengths (360 and 532 nm).…”