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In this work, self-heating effects (SHE) in nanometer-scale metal-oxide-semiconductor field-effect transistor structures—namely, FinFETs (FFs), nanosheet gate-all-around FETs (NSFs), and nanowire gate-all-around FETs (GAAFs)—are investigated via three-dimensional device electrothermal simulations using technology computer-aided design software tools. Initially, transistor design parameter values are set so that their on-state currents are similar for the same operating voltage (VDD). It is found that NSFs and GAAFs are more susceptible to SHE and that p-channel transistors have higher peak internal temperatures than do their n-channel counterparts due to the poor thermal conductivity of the silicon-germanium used as the p-type source/drain material. Subsequently, the on-state currents of FFs, NSFs, and GAAFs are compared under the constraint of identical peak internal temperature, which is required to ensure long-term reliability, revealing that NSFs and GAAFs offer no performance advantage over FFs under this constraint. Design optimization of p-channel NSFs for minimal SHE is subsequently investigated. It is found that with such optimization, NSFs operating at lower VDD (for similar SHE) can achieve similar on-state current as FFs. [ABSTRACT FROM AUTHOR]

The effects of oxygen-inserted (OI) layers and a low-temperature-deposited oxide (LTO) capping layer on rapid thermal activation of ultrashallow implanted boron, phosphorus, and arsenic atoms in silicon (Si) are investigated using sheet resistance (R sh ) measurements, secondary ion mass spectrometry analyses, and technology computer-aided design simulations. The experimental findings suggest that the electrical activation of dopants in Si is not significantly affected by the presence of OI layers so that they can be effective for achieving lower R sh along with shallower junction depth, thanks to reduced dopant loss and diffusion during thermal annealing. On the other hand, an LTO capping layer is found to result in larger R sh associated with the lower peak active dopant concentration as a result of dopant segregation and/or reduced uphill diffusion. The presence of OI layers is found to mitigate these detrimental effects. [ABSTRACT FROM AUTHOR]