Sol-gel Synthesis of LaAlO₃; Epitaxial Growth of LaAlO₃ Thin Films on SrTiO₃(100)

Abstract

A LaAlO3 precursor solution was prepared via an all alkoxide sol-gel route. The solution of lanthanum methoxyethoxide and aluminum methoxyethoxide in 2-methoxyethanol was prepared via ligand exchange starting from lanthanum isopropoxide and aluminum sec-butoxide and was used to make both LaAlO3 powders and films. Complete hydrolysis of the solution formed a gel that yielded well-crystallized LaAlO3 powders when fired in air at 800 °C. A partially hydrolyzed solution was spun-cast on SrTiO3 (100) single crystal substrates. Epitaxial films of LaAlO3 were subsequently formed during pyrolysis in O2 at 800 °C in a rapid thermal annealing furnace for a total of 8 min. The films were strongly c-axis oriented, verified by x-ray rocking curve results from the (003) plane with full-width at half-maximum (FWHM) = 0.87°, and had good in-plane texture shown by a φ scan of the (202) plane with FWHM = 1.07°.

Volatile Surfactant-Assisted MOCVD: Application to LaAlO3 Thin-Film Growth

“…[6] However, there have been few reports of the successful deposition of LaAlO 3 films of high crystalline quality. The only reports in the literature to date have been of epitaxial LaAlO 3 films grown by pulsed laser deposition (PLD), [6,7] radio frequency (RF) magnetron sputtering, [8] and sol-gel [9] on perovskite substrates (SrTiO 3 and LaAlO 3 itself). Attempts to grow LaAlO 3 on Si, MgO, Al 2 O 3 , CeO 2 , and YSZ led to amorphous, or at best polycrystalline, films.…”

MOCVD of LaAlO3 Films from a Molten Precursor Mixture: Characterization of Liquid, Gas, and Deposited Phases

“…[5] Moreover, the growing demand for fabrication of multilayer superconductor±insulator± superconductor (SIS) arrays, has spurred, over the past few years, intense scientific investigation on the growth of buffers, interlayers or overlayers suitable for high T c oxide films. Few studies have been reported on the growth of LaAlO 3 by physical vapor deposition (PVD) techniques [6] on Si substrates, and by sol±gel processes on sapphire [7] and SrTiO 3 [8] substrates. The metal±organic (MO) CVD technology proved an interesting alternative or complement to PVD techniques.…”

Chemical Solution Deposition of Lanthanum Zirconate Buffer Layers on Biaxially Textured Ni–1.7% Fe–3% W Alloy Substrates for Coated-conductor Fabrication

“…[1][2][3][4][5][6] Rolling assisted biaxially textured substrates are ideal templates for the solution process. A coated conductor is defined as the superconductor deposited on a long-length textured substrate.…”