ABSTRACTLow-loped p-type silicon carbide buffer layers are grown by chemical vapor deposition on conducting and semi-insulating substrates. Capacitance-voltage and electrical admittance techniques are developed for accurate non-destructive characterization. The electrical admittance techniques suggested are capable of measuring the resistivity in a very wide range, up to 7 orders of magnitude. MESFET devices using thick buffer layers on conducting substrates are reported with Ft=8.4 GHz and Fmax=32 GHz.