Silicon carbide (SiC) is mechanically robust, chemically inert, non toxic and biocompatible, so is a good material for application in harsh environment and for biomedical purpose Here we report a study on properties of ?-SiC NWs and SiC layers deposited on silicon. Nanowires has been prepared with carbon oxide (core-shell), silane and propane both by using nickel as catalyst in a CVD and VPE system. Nanowires has been characterised by X-ray diffraction (XRD), by Scanning Electron Microscopy (SEM), Cathodoluminescence (CL) and by means Transmission Electron Microscopy (TEM). XRD patterns confirmed the characteristic peaks of the cubic phase. The room temperature CL spectrum revealed a broad peak centred at about 2.34 eV, related to the indirect band gap transition in ?-SiC, and an intense blue band at about 2.68 eV. TEM images showed the crystalline core, having a <111> growth axis, sheathed by amorphous oxide. Typical SiC planar defects were present mainly on (111) planes, either stacking faults or rotational twins. Selected area electron diffraction from single NWs indicated the main phase as ?-SiC. The SiC thin films were deposited on 2'' 001 Si wafers by means of VPE technique with induction heating in a cold and hot wall reactors. A growth procedure at atmospheric pressure involving several steps (thermal etching, carburisation, epitaxial growth) was implemented. The precursor of choice were dilute SiH4 and C3H8 while H2 was used as carrier gas. The layers have been characterised by XRD, SEM, AFM. X-Ray diffraction evidences SiC(001) film is well oriented whit respect to the substrate having a narrow peak. SEM and AFM observations indicate a smooth film with good morphology.
Growth of 3C-SiC nanowires and layers on Si
MBosi;CFerrari;FFabbri;C FRIGERI;FRossi;
2012
Abstract
Silicon carbide (SiC) is mechanically robust, chemically inert, non toxic and biocompatible, so is a good material for application in harsh environment and for biomedical purpose Here we report a study on properties of ?-SiC NWs and SiC layers deposited on silicon. Nanowires has been prepared with carbon oxide (core-shell), silane and propane both by using nickel as catalyst in a CVD and VPE system. Nanowires has been characterised by X-ray diffraction (XRD), by Scanning Electron Microscopy (SEM), Cathodoluminescence (CL) and by means Transmission Electron Microscopy (TEM). XRD patterns confirmed the characteristic peaks of the cubic phase. The room temperature CL spectrum revealed a broad peak centred at about 2.34 eV, related to the indirect band gap transition in ?-SiC, and an intense blue band at about 2.68 eV. TEM images showed the crystalline core, having a <111> growth axis, sheathed by amorphous oxide. Typical SiC planar defects were present mainly on (111) planes, either stacking faults or rotational twins. Selected area electron diffraction from single NWs indicated the main phase as ?-SiC. The SiC thin films were deposited on 2'' 001 Si wafers by means of VPE technique with induction heating in a cold and hot wall reactors. A growth procedure at atmospheric pressure involving several steps (thermal etching, carburisation, epitaxial growth) was implemented. The precursor of choice were dilute SiH4 and C3H8 while H2 was used as carrier gas. The layers have been characterised by XRD, SEM, AFM. X-Ray diffraction evidences SiC(001) film is well oriented whit respect to the substrate having a narrow peak. SEM and AFM observations indicate a smooth film with good morphology.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
