Growth of boron doped hydrogenated nanocrystalline cubic silicon carbide (3C-SiC) films by Hot Wire-CVD

• Boron doped nc-3C-SiC films prepared by HW-CVD using SiH4/CH4/B2H6.
• 3C-Si-C films have preferred orientation in (1 1 1) direction.
• Introduction of boron into SiC matrix retard the crystallanity in the film structure.
• Film large number of SiC nanocrystallites embedded in the a-Si matrix.
• Band gap values, ETauc and E04 (E04 > ETauc) decreases with increase in B2H6 flow rate.

Boron doped nanocrystalline cubic silicon carbide (3C-SiC) films have been prepared by HW-CVD using silane (SiH4)/methane (CH4)/diborane (B2H6) gas mixture. The influence of boron doping on structural, optical, morphological and electrical properties have been investigated. The formation of 3C-SiC films have been confirmed by low angle XRD, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Fourier transform infra-red (FTIR) spectroscopy and high resolution-transmission electron microscopy (HR-TEM) analysis whereas effective boron doping in nc-3C-SiC have been confirmed by conductivity, charge carrier activation energy, and Hall measurements. Raman spectroscopy and HR-TEM analysis revealed that introduction of boron into the SiC matrix retards the crystallanity in the film structure. The field emission scanning electron microscopy (FE-SEM) and non contact atomic force microscopy (NC-AFM) results signify that 3C-SiC film contain well resolved, large number of silicon carbide (SiC) nanocrystallites embedded in the a-Si matrix having rms surface roughness ∼1.64 nm. Hydrogen content in doped films are found smaller than that of un-doped films. Optical band gap values, ETauc and E04 decreases with increase in B2H6 flow rate.

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