Super-Resolution Fluorescence Imaging for Semiconductor Nanoscale Metrology and Inspection.

The increase in the number and complexity of process levels in semiconductor production has driven the need for the development of new measurement methods that can evaluate semiconductor devices at the critical dimensions of fine patterns and simultaneously inspect nanoscale contaminants or defects. However, conventional optical inspection methods often fail to resolve device patterns or defects at the level of tens of nanometers required for device development owing to their diffraction-limited resolutions. In this study, we used the stochastic optical reconstruction microscopy (STORM) technique to image semiconductor nanostructures with feature sizes as small as 30 nm and detect individual 20 nm-diameter contaminants. STORM imaging of semiconductor nanopatterns is based on the development of a selective labeling method of fluorophores for a negative silicon oxide surface using the charge interaction of positive polyethylenimine molecules. This study demonstrates the potential of STORM for nanoscale metrology and in-line defect inspection of semiconductor integrated circuits.

Tunable electrical properties of multilayer HfSe2 field effect transistors by oxygen plasma treatment.

HfSe2 field effect transistors are systematically studied in order to selectively tune their electrical properties by optimizing layer thickness and oxygen plasma treatment. The optimized plasma-treated HfSe2 field effect transistors showed a high on/off ratio improvement of four orders of magnitude, from 27 to 105, a field effect mobility increase from 2.16 to 3.04 cm2 V-1 s-1, a subthreshold swing improvement from 30.6 to 4.8 V dec-1, and a positive threshold voltage shift between depletion mode and enhancement mode, from -7.02 to 11.5 V. The plasma-treated HfSe2 photodetector also demonstrates a reasonable photoresponsivity from the visible to the near-infrared region of light.

Determination of the absolute thickness of ultrathin Al2O3 overlayers on Si (100) substrate.

The thickness of nanometer Al(2)O(3) films was studied by X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The thickness was determined from mutual calibration of the XPS and TEM measurements. The thickness offset of Al(2)O(3) films was proved to be close to zero by in situ XPS analysis. The thicknesses of a series of Al(2)O(3)/Si (100) films with different Al(2)O(3) thicknesses could be determined by mutual calibration from the thicknesses measured by TEM and XPS. The electron attenuation length of the Al 2p electron was determined as 2.4334 nm in the Al(2)O(3) matrix.