No abstract

The atomic force microscopy-based local oxidation (AFM-LO) of silicon carbide (SiC) is extremely difficult in general, mainly due to their physical hardness and chemical inactivity. Herein, we report the strongly enhanced AFM-LO of 4H-SiC at room temperature without the heating, chemicals or photoillumination. It is demonstrated that the increased tip loading force (∼>100 nN) on the highly doped SiC can produce a high enough electric field (∼8×106 V/cm) under the cathode tip for transporting oxyanions, thereby leading to direct oxide growth on 4H-SiC. The doping concentration and electric field profile of the tip-SiC sample structures were further examined by two-dimensional numerical simulations.

Au/SiO 2 /n-Si metal-oxide-silicon-on-insulator (MOSOI) capacitors were fabricated to study the damage caused by reactive ion etching (RIE) on (1 1 0) oriented silicon-on-insulator (SOI) substrates. The MOSOI capacitors with an etch-damaged SOI layer were characterized by capacitance-voltage (C-V) measurements and compared to the sacrificial oxidation treated samples and the reference samples without etching treatment. The measurements revealed that C-V curves significantly change and a negative voltage shift occurs for plasma-damaged capacitors. The simulated band diagram profiles and potential distribution of the corresponding structures indicate that the C-V shift is mainly due to the removal of a parasitic depletion capacitance (C p ) in the substrate, when the interface charges (Q f ) are present at the gate oxide/SOI interface. For etch-damaged MOSOI samples, the surface roughness and the interface charges (Q f ) have been found to increase by ∼1.94 × 10 12 cm −2 with respect to the reference devices, whereas the increase was reduced for sacrificial-oxidation treated samples, which implies a recovery from the plasma-induced etch damage on SOI structures.