We demonstrate a very-low temperature cleaning technique based on atomic hydrogen irradiation for highly (1 %) tensile strained Ge epilayers grown on metastable, partially strain relaxed GeSn buffer layers. Atomic hydrogen is obtained by catalytic cracking of hydrogen gas on a hot tungsten filament in an ultra-high vacuum chamber. X-ray photoemission spectroscopy, reflection high energy electron spectroscopy, atomic force microscopy, secondary ion mass spectroscopy, and micro-Raman showed that an O- and C-free Ge surface was achieved, while maintaining the same roughness and strain condition of the as-deposited sample and without any Sn segregation, at a process temperature in the 100-300 °C range.
DI GASPARE, L., Sabbagh, D., De Seta, M., Sodo, A., Wirths, S., Buca, D., et al. (2015). Epi-cleaning of Ge/GeSn heterostructures. JOURNAL OF APPLIED PHYSICS, 117, 045306 [10.1063/1.4906616].
Epi-cleaning of Ge/GeSn heterostructures
DI GASPARE, LUCIANA;De Seta M;SODO, ARMIDA;CAPELLINI, GIOVANNI
2015-01-01
Abstract
We demonstrate a very-low temperature cleaning technique based on atomic hydrogen irradiation for highly (1 %) tensile strained Ge epilayers grown on metastable, partially strain relaxed GeSn buffer layers. Atomic hydrogen is obtained by catalytic cracking of hydrogen gas on a hot tungsten filament in an ultra-high vacuum chamber. X-ray photoemission spectroscopy, reflection high energy electron spectroscopy, atomic force microscopy, secondary ion mass spectroscopy, and micro-Raman showed that an O- and C-free Ge surface was achieved, while maintaining the same roughness and strain condition of the as-deposited sample and without any Sn segregation, at a process temperature in the 100-300 °C range.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
