| 摘要 |
Methods are disclosed for forming an SRAM cell having symmetrically implanted active regions and reduced cross-diffusion therein. One method comprises patterning a resist layer overlying a semiconductor substrate to form resist structures about symmetrically located on opposite sides of active regions of the cell, implanting one or more dopant species using a first implant using the resist structures as an implant mask, rotating the semiconductor substrate relative to the first implant by about 180 degrees, and implanting one or more dopant species into the semiconductor substrate with a second implant using the resist structures as an implant mask. A method of performing a symmetric angle implant is also disclosed to provide reduced cross-diffusion within the cell, comprising patterning equally spaced resist structures on opposite sides of the active regions of the cell to equally shadow laterally opposed first and second angled implants.
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