Interfacial control of LaAlO3 films deposited on Si (100) using a thin La–Al–Si–O silicate film as the barrier layer

• Published in: Thin solid films 2006-12, Vol.515 (4), p.2722-2725
• Main Authors: Xiang, W.F., Liu, Y.Z., Lu, H.B., Yan, L., He, M., Chen, Z.H.
• Format: Article
• Language: English
• Subjects: Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Interfaces; Lanthanide aluminium oxide; Laser-assisted molecular beam epitaxy; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Molecular, atomic, ion, and chemical beam epitaxy; Physics; Theory and models of film growth; Transmission electron microscopy; X-ray photoelectron spectroscopy
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2006.03.006

Amorphous LaAlO3 thin films have been deposited by laser molecular beam epitaxy system on Si substrate with an abrupt interface. The formation of the interface between LaAlO3 and silicon was investigated in detail using high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy. When several atomic-thick LaAlO3 film was deposited at low temperature and subsequently annealed at high vacuum, a stable Si–La–Al–O silicate thin layer was formed. Using this very thin film as a buffer layer, LaAlO3 films can be deposited with an atomically defined interface at the high temperature and oxygen pressure conditions. With good understanding of the formation mechanism for the interfacial structure, we can control the interface between high-k oxide and Si substrate via optimized deposition parameters and specific growth sequences.