Radiation-induced inter-device leakage is studied using an analytical model and TCAD simulation. There were some different opinions in understanding the process of defect build-up in trench oxide and parasitic leakage path turning on from earlier studies.To reanalyze this problem and make it beyond argument,every possible variable is considered using theoretical analysis,not just the change of electric field or oxide thickness independently. Among all possible inter-device leakage paths,parasitic structures with N-well as both drain and source are comparatively more sensitive to the total dose effect when a voltage discrepancy exists between the drain and source region.Since N-well regions are commonly connected to the same power supply,these kinds of structures will not be a problem in a real CMOS integrated circuit.Generally speaking,conduction paths of inter-device leakage existing in a real integrated circuit and under real electrical circumstances are not very sensitive to the total ionizing dose effect. Radiation-induced inter-device leakage is studied using an analytical model and TCAD simulation. There were some different opinions in understanding the process of defect build-up in trench oxide and parasitic leakage path turning on from earlier studies. About realyalyze this problem and make every possible variable is considered using theoretical analysis, not just the change of electric field or oxide thickness independently. Among all possible inter-device leakage paths, parasitic structures with N-well as both drain and source are comparatively more sensitive to the total dose effect when a voltage discrepancy exists between the drain and the source region. Since N-well regions are commonly connected to the same power supply, these kinds of structures will not be a problem in a real CMOS integrated circuit. Generalized speaking, conduction paths of inter-device leakage existing in a real integrated circuit and under real electrical cases are not very sensitive to the tot al ionizing dose effect.