Analytical model of buried air partial SOI LDMOS

A two-dimensional analytical model has been proposed for the Air Partial Silicon-On-Insulator (APSOI) LDMOS in this paper for the first time. The analytical solutions for the device are derived on the basis of the two-dimensional Poisson equation. An electric field modulation model that takes into account both the lateral and vertical electric field is proposed. The surface electric field is modulated through the variation of buried layer parameters with electric field modulation effect. Under the same simulation parameters, the breakdown voltage of APSOI LDMOS is 140% higher than that of traditional SOI and 93% higher than that of the traditional Silicon-On-Insulator structure with Step-Doped Drift region (SDDSOI). Also, it has been researched that the role of the key structural parameter in device performance is consistent with the expected results of the model, which proves that the effectiveness of electric field modulation effect and our model has guiding significance for device parameter optimization.