Separation of Gate Diffusion Salicides Without Use of Additional Masks
Original Publication Date: 1987-Jan-01
Included in the Prior Art Database: 2005-Jan-31
This article relates to a process sequence used to avoid the problems associated with simultaneous silicide formations in semiconductor gate and shallow source/drain diffusion regions without the need for additional mask steps. When one self-aligned silicide (salicide) process step is used on both the gate and source/drain regions simultaneously, the process is detrimental to the shallow source/drain diffusions located below the gate structure. By separating the process steps used to salicide the gates and the shallow source/drain diffusion regions, the conflicting needs of the two regions are enhanced. By using one refractory metal as a block for selective salicidation using another refractory metal, the gate area salicidation is separated from the shallow source/drain diffusion area salicidation.