TY - GEN
T1 - Synthesis of light emitting Ge nanocrystals by reactive RF sputtering
AU - Hernández-Hernández, Arturo
AU - Rangel-Kuoppa, Víctor Tapio
AU - Plach, Thomas
AU - De Moure-Flores, Francisco
AU - Quiñones-Galvan, José G.
AU - Zepeda, Karen E.Nieto
AU - Zapata-Torres, Martin
AU - Meléndez-Lira, Miguel
PY - 2011
Y1 - 2011
N2 - In this work we report the results of the synthesis, structural and optical characterization of SiO2/Ge/SiO2 heterostructures by reactive RF sputtering. The SiO2 films were grown by reactive sputtering employing a plasma mixture of oxygen and argon. The Ge layer was grown employing an Ar atmosphere. The samples were prepared on p-type Si (1 1 1) substrates by reactive sputtering. The effect of the partial pressure of oxygen on the electronic properties of the heterostructure is reported[1]. Structural characterization was carried out by grazing angle X-ray difraction. Surface roughness was quantified by atomic force microscopy. The presence of Ge nanocrystals (Ge-NCs) was evidenced by X-ray diffraction. The vibrational properties were studied by Raman spectroscopy. The Raman spectra showed modes associated to germanium indicating the formation of low dimensionality germanium particles embedded within a SiO2 matrix. Photoluminescence emission is observed around ∼1.7 eV and it is associated to the quantum confinement of carriers in Ge-NCs. Ohmic contacts were deposited using a van der Pauw geometry employing an a AuSb alloy for the contacts. Temperature dependent Hall (T-Hall) measurements were done between 35 K and 150 K, using the van der Pauw method. The results indicated low resistivity values that could be explained due to some variable range hopping conduction mechanism.
AB - In this work we report the results of the synthesis, structural and optical characterization of SiO2/Ge/SiO2 heterostructures by reactive RF sputtering. The SiO2 films were grown by reactive sputtering employing a plasma mixture of oxygen and argon. The Ge layer was grown employing an Ar atmosphere. The samples were prepared on p-type Si (1 1 1) substrates by reactive sputtering. The effect of the partial pressure of oxygen on the electronic properties of the heterostructure is reported[1]. Structural characterization was carried out by grazing angle X-ray difraction. Surface roughness was quantified by atomic force microscopy. The presence of Ge nanocrystals (Ge-NCs) was evidenced by X-ray diffraction. The vibrational properties were studied by Raman spectroscopy. The Raman spectra showed modes associated to germanium indicating the formation of low dimensionality germanium particles embedded within a SiO2 matrix. Photoluminescence emission is observed around ∼1.7 eV and it is associated to the quantum confinement of carriers in Ge-NCs. Ohmic contacts were deposited using a van der Pauw geometry employing an a AuSb alloy for the contacts. Temperature dependent Hall (T-Hall) measurements were done between 35 K and 150 K, using the van der Pauw method. The results indicated low resistivity values that could be explained due to some variable range hopping conduction mechanism.
KW - Efros-Shkovskii hopping
KW - Ge Nanocrystals
KW - Light emitting
KW - Reactive RF Sputtering
UR - http://www.scopus.com/inward/record.url?scp=80053223799&partnerID=8YFLogxK
U2 - 10.4028/www.scientific.net/SSP.178-179.61
DO - 10.4028/www.scientific.net/SSP.178-179.61
M3 - Contribución a la conferencia
SN - 9783037852323
T3 - Solid State Phenomena
SP - 61
EP - 66
BT - Gettering and Defect Engineering in Semiconductor Technology XIV, GADEST2011
PB - Trans Tech Publications Ltd
T2 - 14th International Biannual Meeting on Gettering and Defect Engineering in Semiconductor Technology, GADEST2011
Y2 - 25 September 2011 through 30 September 2011
ER -