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In this study, the destruction of the contrast agent Sonazoid (GE Healthcare, Oslo, Norway) was measured in vitro as a function of centre frequency (2-3 MHz), acoustic amplitude (0.66-1.6 MPa), pulse length (2-16 cycles) and PRF (0.5-8.0 kHz). Up to 82% of microbubbles were destroyed after exposure to a single 1.6 MPa acoustic pulse (16 cycles, 2.5 MHz and PRF of 1.0 kHz), while at a low amplitude of 0.66 MPa, fractional destruction increased gradually from 0 to 40% after exposure to 9 (identical) pulses. Fractional destruction increased from approximately 8 to 66% as pulse length was changed from 2 to 16 cycles following exposure to a single 2.5 MHz, 1.3 MPa pulse. As the PRF was increased from 0.5 to 8.0 kHz, shorter exposure time intervals (from 4.8 to 1.2 ms) were needed to achieve the same fractional destruction of 80%. Conversely, as the transmit frequency was increased from 2 to 3 MHz the fractional destruction decreased (by more than half within the first 3 pulses). The influence of changes in acoustic pressure and duty cycle on the destruction of Sonazoid microbubbles was highly statistically significant (p 0.01) with a threshold around 0.67 MPa for a duty cycle of 0.0064. In conclusion, the fractional destruction increases with the duty cycle and the acoustic pressure amplitude and decreases with ultrasonic transmit frequency. Better understanding of the influence of the ultrasound transmit parameters on the destruction of contrast microbubbles should help improve existing contrastassisted imaging modalities and may help develop new techniques for better use of contrast agents.

In this work, we introduce main chain scission resists with new concept for High-NA’s generation and report their lithography performance. Zeon has developed a new resist (ZER02#06M) in order to improve both resolution and lithography performance because conventional Zeon resists generated worse resolution and kissing(C/H), pinching(L/S) defects at tight pitch by top loss. The concreate approaches in order to improve the challenges are that to make scission reaction efficient and to get developability at exposed area higher in changing both monomers and functional groups. Zeon aims to make clear threshold between exposed and un-exposed area and improve low contrast and sensitivity at tight patterns especially. The lithography performance of ZER02#06M with their approaches were able to improve LCDU and margin with low LCDU on litho-performance compared to ZER02#04DM and ZER02#05M. Additionally, Zeon resists are indicated to have long-terms stability during litho-process with delay.