Modelling of the degradation mechanisms has a crucial role during the aging analysis, which determines the accuracy of the lifetime estimation. Conventionally, analytical and semi-empirical models are utilized during the aging analysis. Analytical models employ deterministic equations during the degradation calculation and they can be scaled for different technology nodes; hence providing flexibility. However, scaling errors and approximations during the model development may degrade the accuracy. On the other hand, semi-empirical models are generated via accelerated aging test (AAT) performed on the silicon, which often promise more reliable results for a given technology. This paper comprehensively examines the semi-empirical modelling process from test chip design to AAT experiments.