Low temperature (~ 250 °C) layer exchange crystallization of Si1 − xGex (x = 1–0) on insulator for advanced flexible devices

Abstract

Low-temperature (~250°C) layer exchange crystallization of poly-Si1−xGex (x=1–0) films on insulators has been investigated for realization of advanced flexible devices. We propose utilization of Au as catalyst to enhance the crystallization at low temperatures. By annealing (~250°C, 20h) of the a-Si1−xGex (x=1–0)/Au stacked structures formed on insulating substrates, the SiGe and Au layers exchange their positions, and Au/poly-SiGe stacked structures are obtained. The Ge fractions of the obtained poly-SiGe layers are identical to that of the initial a-SiGe layers, and there is no Si or Ge segregation. This low temperature crystallization technique enables poly-SiGe films on plastic substrates, which are essential to realize advanced flexible devices.