TY - GEN

T1 - Semiconductor nanostructures in crystalline rare earth oxide for nanoelectronic device applications

AU - Laha, Apurba

AU - Bugiel, E.

AU - Ranjith, R.

AU - Osten, H. J.

AU - Fissel, Andreas

AU - Afanas'Ev, V. V.

AU - Badylevich, M.

PY - 2010

Y1 - 2010

N2 - In this paper, we will demonstrate a novel approach to incorporate Si and/or Ge nanostructures into crystalline rare earth oxides using molecular beam epitaxy (MBE) for nanoelectronic devices application. By efficiently exploiting the growth kinetics during MBE we succeeded in creating semiconductor nanostructures exhibiting various dimensions, ranging from three dimensionally confined quantum dots (QDs) to the quantum wells, where the particles are confined in one dimension. The crystalline rare earth oxide that has been used in this study is the epitaxial gadolinium oxide (Gd2O3). The monolithic heterostructures comprised of Gd2O3-Ge/Si- Gd2O3 grown on Si substrate exhibit excellent crystalline quality with atomically sharp interface. The room temperature capacitance-voltage measurements performed on a metal oxide semiconductor (MOS) structure with embedded Si, Ge and Si(1-x)Gex QDs into oxide exhibit the electron storage density of 8*1012 cm -2, correspond to two electron per quantum dot and large retention time (>105sec) exhibiting its potential in future nonvolatile memory devices. In addition, silicon quantum dots imbedded in lattice-matched Gd2O3 matrix exhibit large size-dependent bandgap widening. Measurements of photocharging spectra of these crystals indicate only marginal variation of the photoionization threshold energy. The latter suggests that most of the confinement-induced bandgap width variation is caused by the upward shift of the Si nanocrystal (QDs) conduction band bottom.

AB - In this paper, we will demonstrate a novel approach to incorporate Si and/or Ge nanostructures into crystalline rare earth oxides using molecular beam epitaxy (MBE) for nanoelectronic devices application. By efficiently exploiting the growth kinetics during MBE we succeeded in creating semiconductor nanostructures exhibiting various dimensions, ranging from three dimensionally confined quantum dots (QDs) to the quantum wells, where the particles are confined in one dimension. The crystalline rare earth oxide that has been used in this study is the epitaxial gadolinium oxide (Gd2O3). The monolithic heterostructures comprised of Gd2O3-Ge/Si- Gd2O3 grown on Si substrate exhibit excellent crystalline quality with atomically sharp interface. The room temperature capacitance-voltage measurements performed on a metal oxide semiconductor (MOS) structure with embedded Si, Ge and Si(1-x)Gex QDs into oxide exhibit the electron storage density of 8*1012 cm -2, correspond to two electron per quantum dot and large retention time (>105sec) exhibiting its potential in future nonvolatile memory devices. In addition, silicon quantum dots imbedded in lattice-matched Gd2O3 matrix exhibit large size-dependent bandgap widening. Measurements of photocharging spectra of these crystals indicate only marginal variation of the photoionization threshold energy. The latter suggests that most of the confinement-induced bandgap width variation is caused by the upward shift of the Si nanocrystal (QDs) conduction band bottom.

KW - Molecular beam epitaxy

KW - Quantum dot memories

KW - Rare earth oxide

KW - Semiconductor nanostructure

UR - http://www.scopus.com/inward/record.url?scp=79951698391&partnerID=8YFLogxK

U2 - 10.1109/ICM.2010.5696129

DO - 10.1109/ICM.2010.5696129

M3 - Conference contribution

AN - SCOPUS:79951698391

SN - 9781612841519

T3 - Proceedings of the International Conference on Microelectronics, ICM

SP - 248

EP - 251

BT - 2010 International Conference on Microelectronics, ICM'10

T2 - 2010 International Conference on Microelectronics, ICM'10

Y2 - 19 December 2010 through 22 December 2010

ER -