Slim Spacer Implementation to Improve Drive Current

Abstract

Slim spacers are implemented in transistor fabrication. More particularly, wide sidewall spacers are initially formed and used to guide dopants into source/drain regions in a semiconductor substrate. The wide sidewall spacers are then removed and slim sidewall spacers are formed alongside a gate stack of the transistor. The slim spacers facilitate transferring stress from an overlying pre metal dielectric (PMD) liner to a channel of the transistor, and also facilitate reducing a resistance in the transistor by allowing silicide regions to be formed closer to the channel. This mitigates yield loss by facilitating predictable or otherwise desirable behavior of the transistor.

1 . A transistor formed on a semiconductor substrate, comprising:
 a gate stack;   sidewall spacers on either side of the gate stack;   source/drain regions in the substrate on either side of the gate stack and sidewall spacers, the sidewall spacers having a width between about 10 nm and about 30 nm.   
   
   
       2 . The transistor of  claim 1 , comprising:
 silicide regions in the substrate over the source/drain regions.   
   
   
       3 . The transistor of  claim 2 , comprising:
 a pre metal dielectric (PMD) liner over the silicide regions, sidewall spacers and gate stack, where the sidewall spacers facilitate transferring stress from the PMD liner to a channel region in the substrate below the gate stack and between the source/drain extension regions.