Strained Nanosheet Channels Using an Interposer Stress Layer

A sacrificial layer is introduced as an intermediary component during the manufacturing process. This sacrificial layer is deposited over the channel region, patterned to define source and drain regions, and subsequently removed to create voids that are filled with conductive material. This intermediary approach enables precise formation of source/drain regions and stress application to the channel without requiring complex direct patterning methods, thereby improving gate control while managing manufacturing complexity

The source and drain regions are formed in advance before the final gate structure is completed. The sacrificial layer is deposited and patterned prior to gate formation, allowing preliminary definition of active regions. This preliminary action enables better control of the channel region and facilitates subsequent gate-all-around formation without increasing overall process complexity

Traditional mechanical direct-patterning methods for forming source and drain regions are replaced with a chemical deposition and removal process. The sacrificial layer is deposited using chemical vapor deposition or atomic layer deposition, then selectively removed through chemical etching or oxidation. This substitution of mechanical patterning with chemical processes enables better control at scaled dimensions while maintaining manufacturing efficiency

The manufacturing approach changes from direct physical patterning to a multi-step process involving deposition parameters, temperature control, and chemical reaction parameters. By controlling deposition thickness, etch selectivity, and removal conditions, precise feature formation is achieved at scaled dimensions. This parameter-based control enables continued scaling while managing process complexity through well-established semiconductor fabrication techniques