Electrical and optical characterizations of TiC/porous Si/Si structures

In this paper, the electrical and optical behaviour of a new porous silicon (PS) based structure based on a titanium carbide (TiC) covered PS structure has been studied. The layer of the titanium carbide was deposited by radio frequency (RF) pulverisation of titanium under methane/argon atmosphere. A rectifying behaviour has been observed from the I-V curves of the structures, which suggests a Schottky-like junction. The change in the electrical parameters, such as the ideality factor, resistivity of the films, differential resistance, etc., was attributed to the presence and the increase of hydrogen concentration when the TiC layer increases. The value of the refractive index of the TiC layers is close to that Of Si3N4. The values of the extinction coefficient k indicate that the TiC layers are transparent. Finally, spectral response measurements show that the TiC/PS/Si structure is transparent in the near infrared region. (C) 2004 Elsevier Ltd. All rights reserved.