Evaluation of (110) versus (001) Channel Orientation for Improved nFET/pFET Device Performance Trade-Off in Gate-All-Around Nanosheet Technology

Stacked gate-all-around nanosheet (NS) pFET and nFET transistors have been fabricated on Si (110) and Si (001) substrates to determine the device performance dependence on Si channel orientation for short and long-channel NS devices. Systematic studies showed that pFET (110) NS channels have superior hole mobility with performance that is less sensitive to channel thickness than in (001) NS channels. It is also shown that the degradation in the electron mobility for nFET (110) NS channels is significantly smaller compared to the improvement in the hole mobility. Therefore, integrating NS transistors on Si (110) substrates instead of on the conventional Si (001) substrates will lead to better overall performance.