Patent ID: 6573166
Filing Date: 2003-06-03
Classification: H01L

Abstract:
A method for fabricating lightly doped drains (LDD) having different resistance values, the method comprising:providing a semiconductor wafer, a substrate of the semiconductor wafer comprising a first active area and a second active area set on the substrate; forming a first gate and a second gate on the first active area and the second active area, respectively; performing a first ion implantation process to implant dopants of a first electric type on a surface of portions of the substrate within the second active area; performing a second ion implantation process to implant dopants of a second electric type on surfaces of portions of the substrate within the first active area and the second active area, the first electric type and the second electric type are different; and activating the dopants of each electric type and neutralizing portions of the dopants of each electric type to form, respectively, a first LDD and a second LDD ad and the to the first gate and the second gate, the first LDD and the second LDD having different resistance values.