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In this paper, we carried out the two-dimensional (2D) strain measurement in sub-10 nm SiGe layer; images were obtained by dark-field electron holography (DFEH). This technique is based on transmission electron microscopy (TEM), in which dark-field holograms were obtained from a (400) diffraction spot. The measured results were compared to the X-ray diffraction (XRD) results in terms of the strain value and the depth of strain distribution in a very thin SiGe layer. Subsequently, we were able to successfully analyze the 2D strain maps along the [100] growth direction of the nanoscale SiGe region. The strain was measured and found to be in the range of 1.8–2.4%. The strain precision was estimated at 2.5 × 10 −3 . As a result, the DFEH technique is truly useful for measuring 2D strain maps in very thin SiGe layers with nanometer resolution and high precision.

We have researched low temperature silicon oxide (SiO2) with improved electrical properties and excellent film step-coverage. In-situ O2 plasma densification (DENSIFICATION) effect on SiO2 that has been deposited by PE-ALD at temperature (2 network defects by the oxygen radicals. Angle Resolved X-ray Photoelectron Spectroscopy (AR-XPS) analysis was carried out to observe the core-level binding energies shifts (chemical shifts) in the different SiO2 films. The characteristics of wet etch rate of high quality low temperature SiO2 demonstrated lower than high temperature LP-CVD SiO2 values. Compared to LP-CVD SiO2, PE-ALD SiO2 with DENSIFICATION showed excellent I-V characteristics with lower leakage current and similar to the thermal SiO2 carrier transport plot.

Recent years have seen a great deal of progress in the development of transmission electron microscopy-based techniques for strain measurement. Dark-field electron holography (DFEH) is a new technique offering configuration of the off-axis principle. Using this technique with medium magnification (Holo-M), we carried out strain measurements in nanoscale-triangular SiGe/(001) Si with (004), (2-20) and (-111) diffraction spots. The reconstruction of holograms and interpretation of strain maps in term of strain precision were discussed and the strain distributions in the SiGe/(001) Si patterns were visualized. Based on linear anisotropic elastic theory for strain simulation, the simulated results obtained by the finite element method compared with the experimental results acquired by DFEH. The strain values were found to be 0.9-1.0%, 1.1-1.2% and 1.0-1.1%, for the (004), (2-20) and (-111) diffracted beams, respectively, and the strain precisions were determined to be ~2.1 × 10-3, 3.2 × 10-3 and 9.1 × 10-3 for the corresponding diffraction spots. As a result, DFEH is highlighted as a powerful technique for strain measurement, offering high-strain precision, high-spatial resolution and a large field of view.

Chemical, physical, and electrical characteristics of high quality silicon dioxide (SiO2) films grown using low temperature plasma enhanced atomic layer deposition (PE-ALD) have been investigated as a buffer layer for three dimensional vertical nand flash memory devices. The comparative angle resolved x-ray photoelectron spectroscopy studies show the plasma treatment cycle causes to shift the core level binding energy (chemical shifts) in the SiO2 film. The wet etch rates with respect to plasma treatment cycle times were varied due to curing of the SiO2 network defects by Ar+ ions and oxygen radicals. It is assumed that the angle between the bonds linking SiO4 tetrahedra is a critical point understanding the variation in wet etch rate of SiO2. The features of wet etch rate of low temperature high quality SiO2 demonstrated lower than high temperature low-pressure chemical vapor deposition (LP-CVD) SiO2 values. In addition, the better step-coverage compared to that of the LP-CVD SiO2 film was achieved from the deep trench structure having the 20:1 aspect ratio. PE-ALD SiO2 with plasma treatment cycle showed excellent I–V properties with higher breakdown voltage compared to LP-CVD SiO2 and similar to the thermal SiO2 carrier transport plot.