1：Experimental Design and Method Selection:

The study uses a top-down self-aligned-double-patterning I-line lithography process (sidewall transfer lithography) to fabricate SiNW FETs on 4-inch wafers, with HfO2 encapsulation for biosensing. Electrical characterization and DNA hybridization detection are performed in dry environment to avoid charge screening issues.

2：Sample Selection and Data Sources:

p-type SOI wafers with crystalline silicon thickness of 55 nm and buried oxide layer thickness of 145 nm are used. Devices include SiNWs and silicon ribbons with varying geometries (length, width, number of nanowires).

3：List of Experimental Equipment and Materials:

Equipment includes Applied Materials P5000 cluster tool for etching, ALD for HfO2 deposition, RIE systems, PECVD for SiO2 deposition, PVD for metal deposition, probe stations (Cascade 12000, Karl Süss), parameter analyzers (HP 4155, Keithley 4200-SCS), fluorescence microscopes (Olympus BX41M, Zeiss LSM700 confocal). Materials include SOI wafers, SiO2, a-Si, SiN, HfO2, APTES, glutaraldehyde, DNA probes and targets, buffers.

4：Experimental Procedures and Operational Workflow:

Fabrication involves SOI wafer thinning, SiNW definition using STL, dielectric integration (HfO2 deposition), source/drain formation, contact formation, biofunctionalization (silanization, DNA grafting), and DNA hybridization. Electrical measurements are done before and after each functionalization step. Fluorescence imaging confirms DNA hybridization.

5：Data Analysis Methods:

Threshold voltage shifts are extracted from ID-VBG curves using linear extrapolation. Statistical analysis is performed on multiple devices to assess reproducibility and efficiency. Fluorescence intensity is analyzed using Image Pro plus software.