Mesh Grid of SILVACO TCAD Effect on Net Doping Profile for NMOS Structures

摘要

Process of developing the NMOS structure is performed in 2D SILVACO Athena and Atlas Simulation. The NMOS fabrication process steps were chosen from reference [4]. Mesh grid effect on net doping profile was obtained by varying the grid. Variation of grid was determined through observation between fine mesh and loosen mesh in y-axis. Simulation results show that mesh grid affects the doping concentration inside the substrate. Doping concentration will affect junction depth formation where the net doping of phosphorus shows a different concentration at the surface of substrate. Changes of junction depth formation will then gave an effect to the value of threshold voltage. Observation using sheet resistance of Athena tool shows that having high density mesh in y-axis will results in increases in net doping in polysilicon and highly doped region but reduced the concentration in the lightly doped region.