Method to determine forward gate capacitance of HFETs using resonance effect

A new method to determine gate capacitance under forward bias is presented. The method uses the frequency domain resonance of the real part of the Z₁₁ parameter at microwave frequencies. This method extends the range of conventional CV profiling to higher forward gate bias regions. The result of this method helps to resolve the ambiguity of forward bias gate capacitance in large signal device models