Accurate modeling of large angle tilt and pure vertical implantations: application to the simulation of n- and p-LDMOS backgates

The lateral and vertical extensions of the backgate of complementary laterally diffused metal oxide semiconductor (LDMOS) are simulated. The importance of channeling for a large-angle tilt implantation and a purely vertical (0°) implantation are studied with the atomistic simulator Crystal-TRIM. The three-dimensional (3-D) nature of the large-angle tilt implantation is transposed to two dimensions through the introduction of a pseudo-tilt angle. Both the concept of pseudo-tilt angle and the channeling effects have been integrated in the two-dimensional (2-D) process and device simulator IMPACT. These model improvements give a quantitative agreement of doping profiles and sheet resistances with experiments, and therefore provide a reliable basis for the development of n- and p-LDMOS technologies.