Imaging Extreme Ultraviolet Radiation Using Nanodiamonds with Nitrogen-Vacancy Centers

Extreme ultraviolet (EUV) radiation with wavelengths of 10–121 nm has drawn considerable attention recently for its use in photolithography to fabricate nanoelectronic chips. This study demonstrates, for the first time, fluorescent nanodiamonds (FNDs) with nitrogen-vacancy (NV) centers as scintillators to image and characterize EUV radiations. The FNDs employed are ∼100 nm in size; they form a uniform and stable thin film on an indium–tin–oxide-coated slide by electrospray deposition. The film is nonhygroscopic and photostable and can emit bright red fluorescence from NV0 centers when excited by EUV light. An FND-based imaging device has been developed and applied for beam diagnostics of 50 nm and 13.5 nm synchrotron radiations, achieving a spatial resolution of 30 μm using a film of ∼1 μm thickness. The noise equivalent power density is 29 μW/(cm2 Hz1/2) for the 13.5 nm radiation. The method is generally applicable to imaging EUV radiation from different sources

Infrared and Ultraviolet Spectra of Diborane(6): B₂H₆ and B₂D₆

We recorded absorption spectra of diborane(6), B₂H₆ and B₂D₆, dispersed in solid neon near 4 K in both mid-infrared and ultraviolet regions. For gaseous B₂H₆ from 105 to 300 nm, we report quantitative absolute cross sections; for solid B₂H₆ and for B₂H₆ dispersed in solid neon, we measured ultraviolet absorbance with relative intensities over a wide range. To assign the mid-infrared spectra to specific isotopic variants, we applied the abundance of ¹¹B and ¹⁰B in natural proportions; we undertook quantum-chemical calculations of wavenumbers associated with anharmonic vibrational modes and the intensities of the harmonic vibrational modes. To aid an interpretation of the ultraviolet spectra, we calculated the energies of electronically excited singlet and triplet states and oscillator strengths for electronic transitions from the electronic ground state

Identification of <i>cyc</i>-B₃H₃ with Three Bridging B–H–B Bonds in a Six-Membered Ring

Irradiation of samples of diborane(6), B₂H₆ and B₂D₆, separately and together, dispersed in solid neon near 4 K with tunable far-ultraviolet light from a synchrotron yielded new infrared absorption lines that are assigned to several carriers. Besides H, B, BH, BH₂, BH₃, B₂, B₂H₂, and B₂H₄, previously identified, a further species is assigned on the basis of quantum-chemical calculations of vibrational wavenumbers and intensities to be <i>cyc</i>-B₃H₃ (<i>D</i>_3<i>h</i>, singlet state) in several isotopic variants, which feature three bridging B–H–B bonds in a six-membered ring