Exposure Energy Density Research Articles

Line segment fabrication model analysis of near-field photolithography

This paper proposes an integral formula for the exposure energy density during the movement of a workpiece to enable the exposure energy distribution on a photoresist surface to be investigated. The photoresist is divided into finite nodes and the relative concentration variation of the photoactive compound at each finite node of photoresist interior layer is calculated. Also, the average full-width-at-half-maximum (FWHM) during near-field photolithography is calculated. The average FWHM of a line segment fabricated experimently using near-field photolithography is 215.7 nm at a depth of 10.3 nm.

Exposure times and energy densities for ultrasonic disinfection of Escherichia coli, Pseudomonas aeruginosa, Enterococcus avium, and sewage

We investigated the disinfection of sewage and several bacterial pure cultures relevant to sewage using ultrasound produced by the magnetostrictive material, TERFENOL-D. Particular attention was paid to measuring the ultrasonic exposure time and energy density required to kill bacteria. Ultrasonic power was measured and recorded during the treatments, and bacterial kill curves were constructed based on both exposure time and total energy. In 100 mL of synthetic graywater medium, bacterial pure cultures required from ~5 to 16 min per log kill at moderate intensity (~25 W·cm–2), while a sewage sample took several times longer to experience a 90% kill. The effects of intensity, horn size, sonication medium, and vessel geometry and volume on exposure time and energy density were explored. Intensity, horn size, and the sonication medium had significant effects on bacterial kill by ultrasound, but vessel geometry did not. The volume of the liquid being treated and the treatment time were correlated, indicating that the volume of the disinfection zone was smaller than the volume of the liquid being treated.