Effect of the Ge content on the Schottky barrier height in structures based on Si1 − x Ge x solid solution
Abstract
The subject of investigation is the influence of the Ge content on the Schottky barrier height in Au-p-i-n/Al structures based on Si1 − x Ge x (0 < x < 0.26) solid solutions grown by electron-beam floating-zone melting. In Au-i-Si1 − x Ge x , Au-αGe/Si(Li), Au-αGe/Si, and Au-n-Si1 − x Ge x structures, the height of the barrier is about 1 eV, which exceeds the average value of this parameter for silicon available in the literature. It is shown that an excess Ge concentration in the near-surface region of the Si1 − x Ge x crystal causes self-passivation of the surface, which leads to a rise in the barrier height. In the Au-i-Si1 − x Ge x structures, the Schottky barrier height increases from 0.97 to 1.03 eV as Ge content x increases from 0 to 0.11.