Process-induced charge trapping and junction breakdown instability in deep trench isolation for high voltage Smart Power IC process

In BCD process for high voltage Smart Power IC, junction breakdown instability in DTI(Deep Trench Isolation) process is strongly depend on the process-induced mechanical stress and DTI test pattern shape. The DTI test pattern with sharp corner generates larger charge trap density and larger breakdown voltage shift than that of round corner test pattern. Through 3D TCAD simulation and SEM/TEM analysis, we noticed that sharp corner type has higher process-induced mechanical stress and more silicon dislocation defect than that of round corner type.