Papers by Keyword: KPFM

Abstract: Investigation of the doped areas in 4H-SiC power devices has been done by non-destructive characterization methods. It consists of local surface potential measurements by Kelvin Probe Force Microscopy (KPFM) coupled with scanning electron microscopy (SEM) and µ-Raman spectroscopy. Near-field mappings of the devices’ surface have been realized, allowing us to discern the differently doped areas.

Abstract: A non-destructive technique for the characterization of the doped regions inside wide bandgap (WBG) semiconductor structures of power devices is presented. It consists in local measurements of the surface potential by Kelvin Probe Force Microscopy (KPFM) coupled to micro-Raman spectroscopy. The combined experiments allow to visualize the space charge extent of the doped region using the near-field mapping and to estimate its dopant concentration using the Raman spectroscopy. The technique has been successfully applied for the characterization of a WBG SiC (silicon carbide) device.

Abstract: Single layer graphene is fabricated on the Si face of silicon carbide through thermal decomposition. The thickness of graphene was checked by a combination of ex situ Kelvin probe force microscopy together with Raman spectroscopy and atomic force microscopy. The amount of residual strain induced is calculated to between 1.3% and 0.7%. Results also show that the magnitude of strain increased with growth time while the uniformity of strain improved.

Abstract: We report an investigation of the formation of triangular defects (TDs) in 4H–SiC expitaxial layers using Kelvin probe force microscopy (KPFM) and a nano-indenter. The results provide valuable information on the crystallographic structure, including the polytype nature of the TDs and surface potential profile. The TDs were also characterized using micro-Raman spectroscopy and high-resolution transmission electron microscopy. We found that the TDs were composed of a thick 3C-SiC band, as well as stacking faults (SFs) in the 4H-SiC epilayer.

Abstract: The megasonic cleaning efficiency is evaluated as a function of the angle of incidence of acoustic waves on a Si wafer. Acoustic Schlichting streaming alone is not able to remove nanoparticles smaller than 400 nm. It is shown that oscillating or collapsing behavior of bubbles are responsible for removing nanoparticles smaller than 400 nm during a cleaning process with ultrasound. Optimal particle removal efficiency is obtained around the angle of acoustic transmission of the silicon wafer.