3. Results and discussion
The surface morphologies of Si-NPA and SiC/Si-NPA measured
by FE-SEM are presented in Fig. 1. Si-NPA can be described as
a regular array composed of large quantities of well-separated,
quasi-identical silicon pillars from Fig. 1(a). The inset image is a
high resolution cross-section photograph of an individual Si pillar.
Fig. 1(b) shows the surface morphology of SiC/Si-NPA. It is easy
to find that SiC/Si-NPA inherited the morphological feature of Si-
NPA, i.e., the uniformly distributed pillar array perpendicular to the
sample surface. Judged from the image with higher magnification
times (the inset image) and a cross-section FE-SEM image offered
in a previous work [17], it is determined that the SiC nanocrystals
grown during the carbonization process aggregated together and
formed a continuous film covering all over the surface of Si-NPA,
either the pillar surfaces or the valleys around the pillars.
XRD pattern and Raman shifts for SiC/Si-NPA are presented in
Fig. 2. The peaks locating at 35.5◦, 60.3◦ and 71.8◦ in XRD pattern
are indexed to the diffractions from the (1 1 1), (2 2 0) and (3 1 1)
crystal planes of cubic SiC, respectively. The reflections locating
at 28.1◦ and 47.2◦ are caused by the (1 1 1) and (2 2 0) crystal
planes of Si-NPA. According to Scherrer’s formula, the average
grain size of the crystalline 3C–SiC is calculated to be 15.4 nm.
Raman shifts for SiC/Si-NPA in Fig. 2(b) show two broad bands
centered at ∼796 cm−1 and ∼974 cm−1 which are corresponded
Fig. 2.