A two-dimensional analysis of sheet and contact resistance effects in basic cells of gate-array circuits

Edge contact transistors are widely used in basic cells of gate-array circuits and custom designed circuits. The role of sheet and contact in affecting the performance of these transistors is investigated. A two-dimensional model has been developed to calculate the transistor's effective series resistance at various bias conditions. Very good correlation between the model and experiments has been obtained. It is found that different series resistances are observed in linear and saturation regions for edge contacts transistors in contrast to the conventional transistors. The results show that the effective series resistance of an edge contact transistor is nonuniform and is a complex function of the gate voltage, the drain voltage, and the linear or saturation bias conditions.