DEVICE HAVING HYBRID NANOSHEET STRUCTURE AND METHOD

Smart overview of the Invention

The patent application discusses a device featuring a hybrid nanosheet structure, which includes a stack of nanostructures wrapped by a gate structure. An isolation region separates these stacks from adjacent ones, and the device incorporates a source/drain region adjacent to the nanostructures. A spacer layer is placed on the sidewalls of both the gate structure and the source/drain region, ensuring separation between neighboring transistors' source/drain regions.

As semiconductor integrated circuits (ICs) have evolved, there has been a trend towards smaller, more complex designs that increase functional density while reducing geometry size. This miniaturization enhances production efficiency and reduces costs but also complicates IC processing and manufacturing. The patent introduces innovations in electronic devices, particularly field-effect transistors (FETs), including gate-all-around (GAA) FETs and nanosheet FETs, to address these challenges.

The application describes various embodiments for implementing hybrid logic circuit cells with different active area widths to optimize speed performance and power efficiency. It highlights that devices with fewer sheets in contact with source/drain regions conserve power, while those with more sheets achieve higher speeds. The use of a "Flexible Bottom Insulator" (FBI) is proposed to minimize leakage currents, enhancing the device's performance.

To prevent unwanted growth during epitaxial processes, the patent suggests using a spacer layer over shallow trench isolation (STI) areas, protecting them during subsequent etch operations. This method reduces the risk of polysilicon collapse and maintains structural integrity. The application also details photolithography techniques for patterning nanostructure devices, enabling smaller pitches through double-patterning or multi-patterning processes.

Illustrations within the document showcase various stages of manufacturing FETs, such as nanosheet FETs, with detailed descriptions of cross-sectional views and fabrication steps. These figures demonstrate the practical application of the described methods and structures in creating advanced semiconductor devices.