The characteristic and parametric dimensioning of Enclosed Layout (ELT) MOSFET with various geometric sizes and shapes has been taken into consideration for the study of irradiations and leakage at room temperature, which has been confirmed on several technological platforms. Using the most advanced technologies, parametric changes with minimum W/L ratios, layout area and input capacitance to reduce leakage current can improve the performance. The technique of hardening of the MOSFETs in contrary to total-dose radiation effects in space environment built in enclosure to the enclosed transistor for the elimination of edges, responsible of conventional NMOS transistors leakage path creation. High yielding, high level of integration, radiation immune, high speed, low costing and high volume production are the profit advantages of the enclosed layout.