In this paper, we demonstrate with a case study on a nanocapacitor, the capability of transmission electron microscopy in electron holography mode to be a unique in-situ technique for mapping electric fields and charge distributions on a single device. Such precision is necessary to keep pace with shrinking device dimensions and the ever increasing complexity of device architectures.

This paper discusses the use of optical photothermal infrared (O-PTIR) spectroscopy combined with Raman analysis. The new technique overcomes many of the limitations of conventional FTIR and Raman spectroscopy when used alone. It is based on an infrared-visible pump-probe system that incorporates a wavelength-tunable IR laser that emits a pulsed beam that is combined colinearly with the output of a 532-nm green laser. As the paper explains, infrared radiation is partially absorbed by the test target when the wavelength of the laser resonates with the vibrational mode of the material. This excitation process causes the area under the infrared spot to heat up, in turn, causing local expansion along with changes in the refractive indices. These photothermal effects cycle on and off in synch with the pulsed IR beam and the amplitudes of the on-off states are captured by the co-located visible beam and plotted as a function of wavelength over the tunable range of the IR laser. The diffraction limited spot size of the visible beam is approximately 416 nm, corresponding to a spatial resolution of about 1 μm, which is 30 times more precise than conventional FTIR. In addition, by measuring photothermal effects in localized regions, it is possible to identify chemicals in quantities of matter as small as 0.4 pg. By comparison, the sensitivity of transmission mode FTIR is significantly less at around 100 pg.

Traditionally, reliability defects are addressed by end-of-line electrical measurements and extensive and dedicated testing during packaging. These tests cover almost every known defect condition and ensure product reliability with high confidence, but they occur in the final stage of manufacturing and are quite time intensive. This paper shows that inline reliability metrology based on Raman spectroscopy is an effective approach for early fault detection and can be used to monitor unintended epi growth, strain, lattice defects, stacking faults, dislocations, and post-etch residues. It can also reveal process anomalies and potential material problems. The paper examines the relationship between process parameters and reliability and reviews the enablers of preventive, early-detection inline metrology in the fab.

In this work, we investigate mushroom type phase-change material (PCM) memory cells based on Ge 2 Sb 2 Te 5 . We use low-angle annular dark field (LAADF) STEM imaging and energy dispersive X-ray spectroscopy (EDX) to study changes in microstructure and elemental distributions in the PCM cells before and after SET and RESET conditions. We describe the microscope settings required to reveal the amorphous dome in the RESET state and present an application example involving the failure analysis of a PCM test array made with devices fabricated at IBM’s Albany AI Hardware Research Center.

In this paper, we describe the technique of on-axis transmission Kikuchi diffraction (TKD) in a scanning electron microscope and demonstrate its use in characterizing nanoscale crystal structures and defects in semiconductor materials and devices. We explain how we modified hardware and software to achieve an effective spatial resolution of 2 nm during orientation mapping without decreasing acquisition speed, indexing quality, and other performance parameters. The paper includes illustrations comparing sample-detector geometries for conventional EBSD, TKD, and on-axis TKD. It also presents examples of the types of images that can be obtained using on-axis TKD, including raw crystal orientation maps, diffraction patterns, pattern quality maps, time-resolved orientation maps showing microstructure evolution, and a sparse sample map showing the distribution of quantum dots on an electron transparent support film.

Although the physical limits of CMOS scaling should have been reached years ago, the process is still ongoing due to continuous improvements in material quality and analytical techniques. This paper describes one such technique, electron channeling contrast imaging (ECCI), explaining how it is used to analyze nanoscale features and defects. ECCI allows for fast, nondestructive characterization and has the potential for extremely low detection limits. The detection of low-level defects requires measurements over large areas (usually with the help of automation) to obtain statistically relevant data. For example, automated ECCI mapping routines have been shown to quantify crystal defect densities as low as 1 x 10 5 cm -2 in epitaxially grown Si 0.75 Ge 0.25 . The paper presents various methods to reduce measurement time without compromising sensitivity. It also explains how the mapping routine can be optimized to detect extended crystalline defects in III/V layers, selectively grown on shallow trench isolation patterned Si wafers.