A family of novel surge protection devices with improved parameter control

A novel breakover diode (BOD) structure for overvoltage protection applications is proposed. The structure incorporates a surface breakdown trigger mechanism (SBTM), which facilitates the generation of a range of triggering voltages, independent of the starting material´s resistivity and by modification of only a single process step. Significant reduction in the tolerance of the triggering voltage (V_BF) has also been achieved. The switching point´s dependence on the forward breakdown voltage has virtually been eliminated and independent control of the breakover current (I_BO) is available. Prototype devices exhibit narrow breakover voltage (V_BO) windows and significantly reduced leakage current (I_L) ratings. Experimental results are in good agreement with simulated trends