High-resistance layers in n-type 4H-silicon carbide by hydrogen ion implantation

The effect of hydrogen ion implantation damage on the resistivity of n-type 4H–silicon carbide is investigated. The variation of resistivity as a function of measurement temperature and postimplant annealing temperature is studied. Calculated resistivities obtained from resistance measurements are as high as ${\text{8×10}}^6$ Ω cm when resistances are measured at room temperature. When measured at 250 °C, the resistivity of the implanted layer is ${\text{1×10}}^4$ Ω cm. The resistivity is almost constant for annealings up to 1000 °C. The high-resistance behavior is believed to be related to implantation damage caused by 350 keV ${\mathrm{H}}^{\mathrm{+}}$ implantation. The results of this study can be used to obtain high-resistance regions for device isolation.