ABSTRACT
In this chapter, author presents a simulation study explaining how the contact etch stop layer (CESL) transmits its intrinsic stress to the Si channel. It is demonstrated that the CESL stress transmission is the outcome of several CESL parts acting separately (direct effect) or in association (indirect effect). Several options have been proposed in the chapter to account for the modifications in mobility under stress. The first one is the so-called piezoresistive approach, which relates the strained to unstrained mobility. The second alternative relates the change in mobility to the effective conduction mass, omitting thereby impact of the reduced intervalley scatterings. Any semiconductor device manufacturing process consists of multiple steps, including material layer depositions, etching of the layers or their portions, as well as heating and cooling cycles. Commonly one calculates stresses in the final device structure with different stressor regions by specifying values of intrinsic stresses, which is known as the one-step model, where stresses are calculated only once.
