In state-of-the-art organic transistors, the transit frequency f_T is reported to be f_T = 40 MHz for vertical organic transistors, where a voltage-normalized f_T corresponds to 0.36 MHz V⁻². The reported highest f_T for conventional organic transistors is f_T = 160 MHz, where the voltage-normalized f_T is 0.1 MHz V⁻². While the reported transit frequency f_T of n-MOSFETs for silicon technology when normalized by the applied biases exceeds 300 GHz V⁻². The reported carrier mobility of organic semiconductors is over 100 cm² V⁻¹ s⁻¹, which is almost an order of magnitude lower than that of silicon. However, the transit frequency f_T of organic transistors lags far behind silicon technology by about six orders of magnitude at a comparable device length below 300 nm. In this work, a technology computer-aided design (TCAD) simulator is adjusted to the experimental DC and AC characteristics of the 200 nm device length vertical organic permeable-base transistors (OPBTs) based on C₆₀ as semiconductor. The AC performance of the devices is investigated and quantitatively analyzed the influence and contribution of key design, structure and material parameters that determine f_T and f_max. The feasible ways to enhance and optimize the highest achievable f_T and f_max are identified to reach the (Formula presented.) and overcome the limitations to high-frequency operation in organic transistors.