Preventing the reattachment of nano-particles on the substrate surface is indispensable in the wafer cleaning process. In this paper, transportability of different sized nano-particles were observed, in the shear flow occurring near the surface region that duplicated cleaning process in lab-scale, by using the evanescent field. Sub-100 nm particles affected less flow effect and smaller inertia were less likely to be transported. In case of low speeds of inertial flow, most sub-100 nm particles still remain near the surface.

High polishing performance is required in various resins used for optical components and electronic devices. As a result of analyzing the polishing behavior of resin, it is important to control the wettability on the resin interface in order to improve the polishing performance. We found that polishing performance of fluororesin with higher water repellency can be also improved by increasing the wettability. Based on the analysis results, we propose a concept for improving polishing performance that can be applied to resins in general.

One of the top priorities for oral hygiene is an efficient removal of plaque. In this experimental study, one of the important species which is expected to be produced effectively through reaction catalyzed at the surfce of titanium oxide electrode in liquid is hydroxyl radical (OH). The electrode is built into toothbrush and is electric driven by solar cell installed in the grip. In the predawn of this research, (1) absolute amount, (2) production rate, (3) correlation between experimental condition and (1) (and (2)) must be found. We have started to monitor the OH radicals indirectly by chemical probe method with terephthalic acid, etc.

In regenerative medicine and drug discovery, cutting of soft composite material such as cell or biological tissues is difficult because it is extremely soft and has complex material property. In terms of cutting of such soft composite material, a notable phenomenon has been reported that knife with ultrasonic vibration can improve cutting performance of soft composite material. However, few studies have been researched the relationship between the vibration behavior of blade and cutting performance of soft composite material. In this study, we have examined the mechanism of ultrasonic assisted cutting of soft material in viewpoint of the blade vibration behavior through actual cutting experiment with soft material which has similar rigidity of tissues in human body. As a result, we found that over a certain amplitude parallel to blade and elliptical vibration behavior enables high quality cutting of soft material.

It has been found that the viscoelasticity parameters of cells have a strong correlation with disease. Also, since individual cells have different characteristics, we would like to evaluate multiple cells simultaneously. We are currently developing a cell load test device using a channel with a micro-scale narrowed part.After optimizing the channel shape and materials, load tests on polystyrene particles and yeast were carried out. Finally, it was possible to carry out a stress test of more than 5 minutes on yeast with a diameter of less than 10 microns. In addition, we were able to observe the state of load application using the constriction. In the future, we will conduct a load test on red blood cells and white blood cells that are the same size as yeast, aiming for application to diagnosis.

Photodynamic therapy (PDT) has been an effective treatment for non-melanoma skin cancer - basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). However, conventional PDT requires high power light irradiation because of light absorption from skin, which could cause damage and hurt. Microneedles have been applied as the light transmission platform for various light therapy to improve the light transmission, but current research on Optical Microneedle Lens Array (OMLA) fabrication with uncertain shape and thickness reduce the productivity and performance of OMLA. In this study, an OMLA for the treatment of the non -melanoma skin cancer was fabricated. The ideal dimension of the device was designed through the ray trajectory simulation. Optimized fabrication method and process were adopted to fabricate OMLA of specific dimension. It is expected that the fabricated OMLA could increase light transmission in PDT process. In this way, PDT performed by OMLA with low hurt could be realized to cure more patients with BCC and SCC.