High-quality Ge films on Si substrates using Sb surfactant-mediated graded SiGe buffers
نویسندگان
چکیده
High-quality Ge films were grown on Si substrates by solid-source molecular beam epitaxy using SiGe graded layer and Sb surfactant-mediation technique. Transmission electron microscopy measurements show that samples grown using this method have a lower threading dislocation density than those grown by other typical methods, such as grading at high temperature ~700 °C! only, grading at intermediate temperature ~510 °C! only, and the use of low temperature Si buffer. A relaxed Ge film on a 4-mm-thick graded buffer was grown and shown to have a threading dislocation density of 5.4310 cm and surface roughness of 35 Å. Ge p – i – n diodes were fabricated and tested. Under a reverse bias of 1 V, the p – i – n Ge mesa photodiodes exhibit a very low dark current density of 0.15 mA/cm. © 2001 American Institute of Physics. @DOI: 10.1063/1.1421092#
منابع مشابه
Sb surfactant - mediated SiGe graded layers for Ge photodiodes integrated on
High-quality SiGe and Ge thin films were grown on Si substrates by molecular-beam epitaxy using a technique that combines SiGe composition grading and Sb surfactant mediation. Both transmission electron microscopy and Schimmel defect etch measurements show that the Sb surfactant-mediated SiGe graded buffer layers have lower dislocation densities than those without an Sb surfactant. A systematic...
متن کاملPii: S0040-6090(00)00849-x
A method to grow high-quality SiGe graded buffer layer is presented. The main concept of the method is to use Sb as a surfactant when growing SiGe graded layers. Compared with a Si0.5Ge0.5 graded sample without Sb surfactant, the Sb-assisted Si0.5Ge0.5 graded layer has much smoother surface and a signi®cantly lower threading dislocation density. Thermal conductivity of a symmetrically strained ...
متن کاملA surfactant-mediated relaxed Si0.5Ge0.5 graded layer with a very low threading dislocation density and smooth surface
A method to grow a relaxed Si0.5Ge0.5 graded layer with a very smooth surface and a very low threading dislocation density using solid-source molecular-beam epitaxy is reported. This method included the use of Sb as a surfactant for the growth of a 2 mm compositionally graded SiGe buffer with the Ge concentration linearly graded from 0% to 50% followed by a 0.3 mm constant Si0.5Ge0.5 layer. The...
متن کاملDislocations in Relaxed SiGe/Si Heterostructures
Recent advances in the understanding and control of threading dislocations in substantially relaxed SiGe buffer layers on Si are presented. A model for threading dislocation flow in relaxed graded SiGe buffers is used to determine the potential lower limit of threading dislocation density in relaxed SiGe buffers. Greater densities than expected from the model are seen in relaxed graded alloys w...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2001