Analysis of shielded coplanar waveguide with trapezoidal electrodes

In many fabricated integrated optical devices, the electrodes may have a trapezoidal cross section. A hybrid computational method (the point matching method/the conformal mapping technique) for analyzing the shielded coplanar waveguide with such electrodes is described. This method provides a simple and fast approach to the quasistatic analysis of the structures. The calculated fields are used to estimate the characteristic impedance and microwave effective index of the structures. The effect of the electrode wall angle becomes significant when the angle is smaller than 82°.