A comprehensive study of Ge1−xSix on Ge for the Ge nMOSFETs with tensile stress, shallow junctions and reduced leakage

For the first time, growth of high-quality Ge-rich Ge
_1-x
Si
_x
(0 ¿ × ¿ 0.14) layers on Ge substrate was demonstrated. An effective suppression of the phosphorus diffusion in Ge
_1-x
Si
_x
and a better thermal stability of the nickel germanide on Ge
_1-x
Si
_x
were observed. A higher rectifying ratio with a reduced diode leakage current in n
⁺
-Ge
_1-x
Si
_x
/p-Ge
_1-x
Si
_x
is compared with n
⁺
-Ge/p-Ge. These results indicate that it is suitable for Ge
_1-x
Si
_x
to be used as source/drain (S/D) to fabricate the uniaxial tensile-strained channel Ge nMOSFETs.