Polymer link breakage of polyimide-film-surface using hydrolysis reaction accelerator for enhancing chemical-mechanical-planarization polishing-rate.

In this study, the chemical decomposition of a polyimide-film (i.e., a PI-film)-surface into a soft-film-surface containing negatively charged pyromellitic dianhydride (PMDA) and neutral 4,4'-oxydianiline (ODA) was successfully performed.

Super fine cerium hydroxide abrasives for SiO film chemical mechanical planarization performing scratch free.

Face-centered-cubic crystallized super-fine (~ 2 nm in size) wet-ceria-abrasives are synthesized using a novel wet precipitation process that comprises a Ce precursor, CHN catalyst, and NaOH titrant for a synthesized termination process at temperature of at temperature of 25 °C. This process overcomes the limitations of chemical-mechanical-planarization (CMP)-induced scratches from conventional dry ceria abrasives with irregular surfaces or wet ceria abrasives with crystalline facets in nanoscale semiconductor devices. The chemical composition of super-fine wet ceria abrasives depends on the synthesis termination pH, that is, Ce(OH) abrasives at a pH of 4.

A new frequency domain passive acoustic mapping method using passive Hilbert beamforming to reduce the computational complexity of fast Fourier transform.

Passive acoustic mapping (PAM) is the current state-of-the-art imaging tool for monitoring cavitation activity during focused ultrasound therapy such as blood-brain barrier opening. However, PAM incurs huge computational complexity. To address this issue, frequency-domain PAM (FD-PAM) was proposed.

Comparison study of passive acoustic mapping and high-speed photography for monitoring in situ cavitation bubbles.

The spatiotemporal accuracy of passive acoustic mapping (PAM) for monitoring in situ cavitation bubbles has not been assessed directly via optical means. Here, the cavitation bubbles are monitored from two image sequences obtained simultaneously with PAM and high-speed photography (HSP). The temporal accuracy of PAM for detecting cavitation nucleation and the spatial resolution for cavitation localization are compared with those measured from HSP.

Ultrasonic sector imaging using plane wave synthetic focusing with a convex array transducer.

Synthetic transmit focusing (STF) methods using unfocused waves or plane waves (PWs) have recently been investigated extensively. However, STF using PWs with a convex array (PWSTF-CA) has not been rigorously studied for high-resolution sector imaging. In this paper, the authors suggest an analytical model for accurate characterization of the spatial beam patterns of PWSTF-CA using a large range of either uniformly or non-uniformly distributed PW angles.