Thermal Emission Microscopy Research Articles

`Failure analysis of short-circuit failure of metal-oxide-metal capacitor

Metal-oxide-metal (MOM) capacitors are used widely in semiconductor integrated circuits. This study describes a method for failure analysis of MOM capacitor short-circuit. We present two case examples to highlight the significance of this method. Various techniques are described, such as thermal emission microscopy (ThEM), beam induced resistance change (OBIRCH), photoemission microscopy (PEM), focused ion beam (FIB), and passive voltage comparison (PVC). ThEM could be an effective alternative, albeit with low magnification. OBIRCH could help verify the defect location in the MOM structure, albeit with a large region of interest (ROI). The application of PEM based on an InGaAs detector can reduce the ROI and yield satisfactory fault isolation results. PVC can indicate the metal bridge phenomenon and help guide FIB cross-sectional analysis. To summarize, our observations indicate that PEM and PVC are effective alternatives for the failure analysis of MOM short-circuit failure.

Thermal Emission Microscopy using Lock-in Technique(Detection Technology of Fault Portions with Thermal Emission)

Thermal Emission Microscopy using Lock-in Technique(Detection Technology of Fault Portions with Thermal Emission)

Liquid crystal phases generated by supramolecular self-assembly of biforked amphiphilic imidazoles

Functional groups with the capability of hydrogen bonding are widely used in the molecular design and preparation of liquid crystalline supramolecular systems, a rapidly growing area of materials showing a high sensitivity towards external stimuli. A series of novel imidazole-containing Schiff's bases replenishing the family of supramolecular liquid crystals has been synthesised and characterised by proton nuclear magnetic resonance, Fourier transform infrared, and ultraviolet–visible spectroscopy, and elemental analyses. Variation of lengths of the terminal alkyl substituents in the obtained amphiphilic imidazoles within 6, 8, 10, 12, 14 and 16 carbon atoms leads to significant changes in their thermal behaviour, micro-segregation and supramolecular self-assembly. Lower homologues were non-mesomorphic, while intermediate members of the homologous series exhibited monotropic bilayered smectic and columnar mesophases. A higher homologue with 16 carbon atoms has an increased trend towards crystallisation of the aliphatic chains and did not exhibit mesomorphism again. The liquid crystalline mesophases were identified and investigated by polarised optical microscopy, differential scanning calorimetry, X-ray diffraction and thermal emission microscopy methods. According to X-ray diffraction characteristics, the smectic mesophase has a bilayered structure where the hydrophilic imidazole groups form a continuous hydrogen bonded network. The interface curvature created by the second alkyl chain leads to the appearance of columnar nanostructures in homologues with 12 and 14 aliphatic carbon atoms.

Localized heating in nanoscale Pt constrictions measured using blackbody radiation emission

Using thermal emission microscopy, we investigate heating in Pt nanowires before and during electromigration. The wires are observed to reach temperatures in excess of 1000 K. This is beyond the thermal decomposition threshold for many organic molecules of interest for single molecule measurements with electromigrated nanogaps. Blackbody spectra of the hot Pt wires are measured and found to agree well with finite element modeling simulations of the electrical and thermal transport.

High spatial resolution subsurface thermal emission microscopy

We apply the numerical aperture increasing lens technique to subsurface thermal emission microscopy of Si integrated circuits. We achieve improvements in the amount of light collected and the spatial resolution, well beyond the limits of conventional thermal emission microscopy. We experimentally demonstrate a lateral spatial resolution of 1.4 μm and a longitudinal spatial resolution of 7.4 μm, for thermal imaging at free space wavelengths up to 5 μm.

Carbon Surfaces and Carbon Film Morphology Studied by Emission Electron Microscopy

Carbon is a pervasive contaminant on technologically important surfaces, and has long been of interest in surface science and microscopy. Recent advances in the production of high density carbon films and synthetic diamond films [1,2] have focused attention on the nucleation and growth of carbon on refractory metal substrates, semiconductors and other phases of carbon itself. Some of the issues involved are the role of carbides in promoting diamond nucleation and the specifics of graphite removal from the film through reactive sputtering or conversion to more dense phases (by as yet not understood processes).Emission microscopy, in particular photo- and thermal emission microscopy, is especially suited to the study of carbon film nucleation and growth. Carbides are easily observed. [3] Because several carbon phases have differing work functions, they may be selectively imaged by variation of the incident light wavelength, and thus the photoemission threshold, providing information on film composition in the image. Figures 1 and 2 show a Pt(100) surface covered with CO, atomic carbon and some graphitic areas, imaged with a microscope similar to the one in [3] using an HBO 100 lamp. [4] In figure 2 a 280 nm edge filter was placed in front of the lamp, so that only the graphitic areas (work function below 4.4 eV) are visible. Due to the image contrast in photoemission from differing materials, decoration of steps and defects by carbon is visible. In figure 3 step bunch edges on the Pt(100) surface have been decorated with carbon from the decomposition of ethylene; figure 4 shows another area of the surface where the terraces are carbon coated, and the step edges are “clean.” The slip trace features suggest that the dark lines are mono-atomic steps.[5]