Experimental evidence is given for boron (B) enhanced diffusion of nitrogen (N) in ion-implanted 4H silicon carbide (4H-SiC), when a nitrogen implant is co-doped within an existing boron p-type well. The co-implanted nitrogen is shown to diffuse continuously with time when samples are annealed at 1600 °C—with little movement of the boron p-well implant profile. An effective nitrogen in boron diffusivity at 1600 °C is determined to be at least 60 times larger than that of a mono-doped nitrogen implant.

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High-Voltage MOSFETs are essential devices for complementing and extending the domains of application of any core technology including low-power, low-voltage CMOS. In this paper, we propose and describe advanced Extended-Drain MOSFETs, designed, processed and characterized in ultrathin body and buried oxide Fully Depleted Silicon on Insulator technology (UTBB-FDSOI). These transistors have been implemented in two technology nodes (28 nm and 14 nm) with different silicon film and buried oxide thicknesses (TSi < 10nm and TBOX ≤ 25nm). Our innovative concept of Dual Ground Plane (DGP) provides RESURF-like effect (reduced surface field) and offers additional flexibility for HVMOS integration directly in the ultrathin film of the FDSOI wafer. In this configuration, the primary back-gate controls the threshold voltage (VTH) to ensure performance and low leakage current. The second back-gate, located underneath the drift region, acts as a field plate enabling the improvement of the ON resistance (RON) and breakdown voltage (BV). The trade-off RON.S versus BV is investigated as a function of doping level, length and thickness of the drift region. We report promising results and discuss further developments for successful integration of high-voltage MOSFETs in ultrathin CMOS FDSOI technology.

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Silicon carbide bipolar diodes fabricated by nitrogen implantation with a subsequent annealing at 1100 °C and passivated with a deposited oxide have been characterized. Capacitance– and current–voltage measurements have been made to analyze the quality of the junction. Admittance spectroscopy shows the presence of three peaks: two correspond to nitrogen and aluminum shallow levels; the third one has been more precisely studied by deep level transient spectroscopy. It presents an activation energy of Ev+0.49 eV and is probably due to a hole trap created by the nitrogen implantation.