Tem Investigation of Co-Si Thin Films on S1-xGex/Si

摘要: Cobalt disilicide (CoSi2) is an attractive contact material for Si1-xGex devices due to its low resistivity, Schottky barrier, and good thermal chemical stability. Previous studies have shown that blanket Co films on Si0.80Ge0.20 react at annealing temperatures of 700 °C form CoSi, CoSi2 a Ge-rich alloy; no Co-Ge phases were found. The preferentially reacts with the Si, which can lead Ge segregation island formation. To gain better understanding cobalt silicide formation, electron microscopy investigation Co/Si1-xGex/Si was performed.Si1-xGex (x ≤ 0.3) 64 nm 260-nm thick grown by molecular beam epitaxy 550 phosphorus-doped Si substrates. ranging in thickness from 5 25 electron-beam evaporated (evaporator base pressure < 6.67 x 10-8 Pa) room temperature films.