TY - JOUR

T1 - Integration of low dimensional crystalline Si into functional epitaxial oxides

AU - Laha, Apurba

AU - Bugiel, E.

AU - Dargis, R.

AU - Schwendt, D.

AU - Badylevich, M.

AU - Afanas'ev, V. V.

AU - Stesmans, A.

AU - Fissel, A.

AU - Osten, H. J.

PY - 2009/3

Y1 - 2009/3

N2 - In this work we show that by efficiently exploiting the growth kinetics during molecular beam epitaxy (MBE) one could create Si nanostructures of different dimensions. Examples are Si quantum dots (QD) or quantum wells (QW), which are buried into an epitaxial rare-earth oxide, e.g. Gd2O3. Electrical measurements carried out on Pt/Gd2O3/Si MOS capacitors comprised with Si-QD demonstrate that such well embedded Si-QD with average size of 5 nm and density of 2×1012 cm-2 exhibit very good charge storage capacity with suitable retention (∼105 s) and endurance (∼105 write/erase cycles) characteristics. The Pt/Gd2O3/Si (metal-oxide-semiconductor (MOS)) basic memory cells with embedded Si-QD display large programming window (∼1.5-2 V) and fast writing speed and hence could be a potential candidate for future non-volatile memory application. The optical absorption of such Si-QD embedded into epitaxial Gd2O3 was found to exhibit a spectral threshold maximum up to 2.9±0.1 eV depending on their sizes, inferring a significant influence of quantum confinement on the QD/oxide interface band diagram. Ultra-thin single-crystalline Si-QW with epitaxial insulator (Gd2O3) as the barrier layers were grown by a novel approach based on cooperative vapor phase MBE on Si wafer with sharp interfaces between well and barriers. The current-voltage characteristics obtained for such structure exhibits negative differential resistance at lower temperature, making them a good candidate for resonant tunneling devices.

AB - In this work we show that by efficiently exploiting the growth kinetics during molecular beam epitaxy (MBE) one could create Si nanostructures of different dimensions. Examples are Si quantum dots (QD) or quantum wells (QW), which are buried into an epitaxial rare-earth oxide, e.g. Gd2O3. Electrical measurements carried out on Pt/Gd2O3/Si MOS capacitors comprised with Si-QD demonstrate that such well embedded Si-QD with average size of 5 nm and density of 2×1012 cm-2 exhibit very good charge storage capacity with suitable retention (∼105 s) and endurance (∼105 write/erase cycles) characteristics. The Pt/Gd2O3/Si (metal-oxide-semiconductor (MOS)) basic memory cells with embedded Si-QD display large programming window (∼1.5-2 V) and fast writing speed and hence could be a potential candidate for future non-volatile memory application. The optical absorption of such Si-QD embedded into epitaxial Gd2O3 was found to exhibit a spectral threshold maximum up to 2.9±0.1 eV depending on their sizes, inferring a significant influence of quantum confinement on the QD/oxide interface band diagram. Ultra-thin single-crystalline Si-QW with epitaxial insulator (Gd2O3) as the barrier layers were grown by a novel approach based on cooperative vapor phase MBE on Si wafer with sharp interfaces between well and barriers. The current-voltage characteristics obtained for such structure exhibits negative differential resistance at lower temperature, making them a good candidate for resonant tunneling devices.

KW - Epitaxial gadolinium oxide

KW - Nonvolatile memories

KW - Oxide-semiconductor-oxide quantum well

KW - Resonant tunneling diode

KW - Si quantum dots

UR - http://www.scopus.com/inward/record.url?scp=61349192163&partnerID=8YFLogxK

U2 - 10.1016/j.mejo.2008.06.064

DO - 10.1016/j.mejo.2008.06.064

M3 - Article

AN - SCOPUS:61349192163

VL - 40

SP - 633

EP - 637

JO - Microelectronics journal

JF - Microelectronics journal

SN - 0026-2692

IS - 3

ER -