Simulation Study on Different Integration Schemes to Form Single Diffusion Break

Single diffusion break (SDB), which provides electrical insulation between two finFET devices, is one of the critical steps in finFET semiconductor fabrication. With device dimension scaling down, SDB has shown a growing importance on chip yield performance. In recent years, various SDB approaches have been developed along with integration evolutions to enable smaller process nodes. In this paper, the 3 main SDB approaches, including fin/STI approach, ILD approach and HKMG approach, are investigated systemically by virtual fabrication with Coventor SEMulator3D®. We find unique advantages and disadvantages present for each approach. The fin/STI approach suffers least from aspect ratio and material complexity but has the most demanding requirements on overlay and CD control. Being self-aligned approaches, ILD and HKMG approaches behave well in overlay and CD control. Nevertheless, both methods are more demanding on etch processes due to higher aspect ratio and presence of multiple materials on the stack.