Maskless process for self-aligned contacts

Abstract

A method for forming self-aligned borderless contacts without a masking process, in accordance with the invention, includes forming a shallow trench isolation region about an active area region and forming a gate structure through the active area region. The gate structure and shallow trench isolation region extend above a surface of a substrate, and the substrate has an exposed portion of the between the gate structure and shallow trench isolation region. Undoped polysilicon is deposited over the gate structure, the shallow trench isolation region and the exposed portion of the substrate. The polysilicon is removed from the gate structure and shallow trench isolation region, and remaining polysilicon is doped to form contacts in contact with the substrate.