Patent ID: 6458665
Filing Date: 2002-10-01
Classification: H01L

Abstract:
A halo ion implantation method for a semiconductor device, comprising:preparing a semiconductor substrate having at least one flat zone and doped with an impurity so as to fabricate a semiconductor device with a cell array region and a peripheral circuit region; forming a gate oxide film on the semiconductor substrate; forming a plurality of gate electrodes on the gate oxide film in the cell array region so that each of the gate electrodes is arranged in parallel in a direction horizontal or vertical to the flat zone; and implanting halo ions into the semiconductor substrate using each of the gate electrodes as a mask, wherein the halo ion implantation occurs within predetermined angle ranges for &thgr; and &phgr;, where the absolute value of the product of the tangent of &thgr; and the cosine of &phgr; is greater than the ratio of s divided by h, wherein s is a clearance between the gate electrodes formed in the cell array region, h is the height of a gate electrode, &phgr; is the horizontal angle in a direction in which impurity ions are incident from a direction orthogonal to a longitudinal direction of a gate electrode, and &thgr; is the vertical angle in a direction in which impurity ions are incident from a direction vertical to the surface of the semiconductor substrate to prevent halo ion implantation in the cell array region.