A Stabilized Numerical Scheme to Simulate Synergistic Effect of TID and TDR in Semiconductor Devices

The synergistic effects between total ionizing dose (TID) and transient dose rate (TDR) effects are explored. To implement the analysis, a stable 3D parallel numerical scheme is specially developed. Using the control volume finite element tearing and interconnect (CV-FETI) method, the discontinuous boundary conditions can be included with the usual numerical properties. Newton's method is employed to overcome the nonconvergence brought by the nonlinear property of the drift- diffusion model. Compared to with the commercial COMSOL Multiphysics software, our CV-FETIM shows strong numerical stability on unstructured meshes. The proposed method is validated by comparing the numerical results with those calculated using commercial software. Then, this new solver is applied to simulate MOSFET, STI-based LDMOSFET, and FinFET. By adjusting the dose rate, oxide traps, and interface traps, the independent TID, independent TDR, and TID-TDR synergistic effects are investigated. On picosecond or nanosecond timescales, the duration, amplitude, and decline rate of the radiation-induced photocurrent are studied. Moreover, the influence of interface traps on different surfaces is compared. The numerical results indicated that the developed numerical scheme possesses good stability, accuracy, and applicability.