Analytical Model and Mechanism of Homogenization Field for Lateral Power Devices

The analytical model and mechanism of homogenization field (HOF) for lateral power devices is developed in this article. The HOF structure features periodical voltage sustaining cells connected in series from source to drain, which introduces the periodic field modulation to realize the 3-D homogenization of electric field. In the model, the periodic electric field distribution of the HOF structure is obtained by solving the Poisson’s equation in one half HOF-cell. Then, a design formula is deduced by considering the optimal field distribution. Two lateral double-diffused metal–oxide semiconductor (LDMOS) devices using the HOF structure were fabricated to demonstrate the analytical model. The analytical model is in good agreement with both the simulations and experiments. In the experiments, a low $R_{ \mathrm{\scriptscriptstyle ON},sp}$ of 53.3 $\text{m}\Omega \cdot $ cm2 was realized under a high ${V}_{B}$ of 669.5 V, achieving a HOF LDMOS with high figure of merit FOM $= {V}_{B}^{2}/{R}_{ \mathrm{\scriptscriptstyle ON},sp}$ of 8.41 MW/cm2.