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The decomposition of phenol and 4-chlorophenol by underwater pulsed discharge has been examined. The addition of hydrogen peroxide improved the decomposition rate of phenol by about 2.5 times and that of 4-chlorophenol by about 1.5 times. Analysis using a fluorescent probe suggested that the addition of hydrogen peroxide enhanced the production of hydroxyl radicals by about 3 times. We have also examined the effect of using microbubbles on the decomposition of phenol. The use of only microbubbles resulted in a slight increase of the decomposition rate, while the use of both microbubbles and hydrogen peroxide led to a remarkable enhancement of the decomposition rate by about 3.5 times with the conversion of phenol reaching 70% at discharge time of 3 h, which corresponded to the energy yield of 4.39 × 10â€"9 mol Jâˆ'1. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the removal characteristic of positive-tone novolak photoresists into which B, P. and As ions were implanted with doses of 5 x 1012-5 x 1015 atoms/cm2 at an acceleration energy of 70 keV using atomic hydrogen, and the hardening mechanisms for the photoresists. All of the ion-implanted photoresists with doses up to 5 x 1015 atoms/cm2 were removed without regard for ion species. The removal rates of the photoresists decreased with increasing ion-implantation dose due to hardening of the photoresist surfaces with implantation. The thickness of the surface-hardened layer of the photoresists decreased in the order of B → P → As, and the removal rate increased with decreasing thickness. The energy supplied from the ions to the photoresist concentrated on the surface side in the order of B → P → As, and the impact of the heavier ion on the photoresist was greater than that of the lighter ion. We deduced that the photoresists exhibited carbonization and cross-linkage attributable to the decrease in OH, CH, and 0 Is and the increase in C=C, C is, and if-conjugated systems. [ABSTRACT FROM AUTHOR]

Using environmentally friendly wet ozone instead of chemicals, we removed B-, P-, and As-ion-implanted positive-tone novolak photoresists with an implantation dose of 5 x 10 12-1 x 1016 atoms/cm2 at an acceleration energy of 70 keV. Ion-implanted photoresists with an implantation dose exceeding 5 x 1015 atoms/cm2 could not be removed, but photoresists implanted at doses below 5 X 1013 atoms/cm2 could be removed. Photoresist implanted with B ions at 5 x 1014 atoms/cm2 was removed slowly, but photoresists implanted with P and As ions were not removed at all. The hardness of the photoresist with B ions implanted at 5 x 1014 atoms/cm2 was 1.8 times greater than that of the nonimplanted photoresist (AZ6112), that of the P-ion-implanted photoresist was eight times greater, and that of the As-ion-implanted photoresist was five times greater. The B-ion-implanted photoresist was softer than the Pand As-ion-implanted photoresists. We also obtained the calculation results in which the energy supplied from the B ions to the photoresist was lower than that from P and As ions. We assumed that the ion-implanted photoresists were hardened by cross-linkage due to the energies supplied to the photoresists from the ions. Therefore, we determined that the hardness threshold of the photoresist that could be removed by using wet ozone was twice the hardness of AZ6112. [ABSTRACT FROM AUTHOR]