The effect of beam scanning methods in process transfer

Equipment matching is a major consideration for process transfers between fab areas. When process transfers occur between fabs with similar equipment, simple dose matching is often adequate. However, it is not enough in the ease where transfers occur between fabs with fundamentally different equipment sets. Implant parameters such as tilt angle, twist angle, multiple-positioning and continuous-rotation may have profound effects on uniformity, two-dimensional shadowing, and dopant profiles. These effects, in turn, may result in threshold voltage shifts, changes in drive current, transistor asymmetry, and wide distributions of electrical parameters across wafers.