Fracture testing of silicon cantilever beams (thicknesses 10–20 μm) was performed in situ in a scanning electron microscope by means of an equipment specially designed for this purpose. Beams of various sizes and orientations (〈011〉 and 〈001〉) were manufactured in Si (100) wafers by two different micromachining procedures. The beams were tested by simple bending to fracture, and a number of fundamental fracture parameters were determined from an analytical model of elastic fracture. To verify its validity, the model was utilized to evaluate an experimental E modulus, which was found to agree well with previous results. Fracture limits, fracture strains, and initiating flaw sizes were determined. The maximum fracture limit was very high; about 10 GPa. The strengths of different beams scattered from this value down to practically zero strength, with an average close to 4 GPa. The corresponding fracture strains and initiating flaw sizes were 6% and 3 nm, respectively (maximum strength), and 2% and 17 nm (average strength). Finally, a simple fractography study was performed on the fractured beams.

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Deep level transient spectroscopy measurements of electron traps in MeV proton- and alpha-irradiated n-type silicon have been performed. Six deep levels are found in proton-irradiated samples, while only three appear after alpha irradiation. The influence of the irradiation dose on the defect production is investigated together with the depth concentration profiles. The profiles scale with the nuclear energy deposition, but in the case of the doubly negative charged state of the divacancy at EC −0.24 eV, the peak concentration at the end of the track is less pronounced relative to the tail region towards the surface. It is proposed that the singly negative charged state at EC −0.42 is more probable in a highly distorted lattice and it is shown that the formation of the singly negative charged state of the divacancy dominates the defect production for higher doses.

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In the current COVID‐19 scenario, there is an urgent need for developing efficient and mercury‐free deep‐ultraviolet (deep‐UV) light sources for disinfection applications. AlGaN‐based light‐emitting diodes (LEDs) may be considered as an alternative, but due to their inherent low efficiencies in the deep‐UV spectral region, significant developments are required to address efficiency issues. Here, a mercury‐free chip‐size deep‐UV light source is shown which is enabled by high‐vacuum chip‐scale cavity sealing overcoming the limitations of both mercury lamps and deep‐UV LEDs. These deep‐UV chips are cathodoluminescence based, in which a cavity is created with high vacuum integrity for efficient field‐emission. These chips demonstrate optical output power ≥20 mW (efficiency ≈4%) and, owing to the spectral overlap of phosphor cathodoluminescence spectra and germicidal effectiveness curve, resulted in log 6 (99.9999%) germicidal efficiency. Additionally, these chips offer high reliability, “instant” ON/OFF capability, high operational lifetimes, and low‐temperature dependence with complete design freedom.