Improving the X-ray radiation tolerance of the analog ICs by using OCTO layout style

This paper investigates and compares experimentally the total ionizing dose (TID) effects in the main analog parameters of the fully depleted (FD) OCTO Silicon-On-Insulator (SOI)n-type Metal-Oxide-Semiconductor Field Effect Transistor (MOSFET) (OSM), that presents an octagonal gate geometry, versus its conventional (rectangular gate geometry) counterpart (CSM). The main analog parameters taken into account in this study are the drain current in saturation region (I_DSsat), the maximum transconductance (g_m-max), the transconductance (g_m) over the drain current (I_DS) ratio (g_m/I_DS), the unity voltage gain frequency (f_T), intrinsic voltage gain (A_V) and Early voltage (V_EA). This work demonstrates that OCTO layout style achieved the same relative variation due the TID effects as the conventional for the main analog parameters, but keeping the higher electrical performance related to the LCE and PAMDLE effects. In addition the OSM had a higher tolerance in terms of g_m-max, I_DSsat and V_EA relative variation and f_T and A_V performance in strong inversion regime.