Implicit or automatic detection of social signals, which discriminate animate, intentional objects in the environment, is essential for higher social cognition and its development. Using functional magnetic resonance imaging, we identified the neural substrate of detecting simple visual social signals and examined its functional link with the mechanism of inferring another's mental state. Healthy participants were presented with the eye-gaze shift (EG) and self-propelling motion (SP) under both implicit and explicit task conditions. They also performed a social role-playing game in which mental inference (MI) was implicitly prompted during the presentation of faces (implicit MI). Implicit detection of EG and SP activated the posterior middle temporal gyrus (pMTG) bilaterally, whereas the right posterior superior temporal sulcus was activated during the explicit conditions. We revealed that the individual variation in neural response in the right pMTG during implicit eye-gaze detection explains the individual tendency to recruit the regions implicated in mental-state inference (medial prefrontal cortex, temporal pole and striatum) during the implicit MI task. Our results suggest that the implicit detection of visual social signals involves the pMTG and underlies the development of higher social cognition.
Morpho butterfly scales have a morphological structure with a nanostructure. The morpho structure has a structure in which nanofins are repeated, and when light hits the structure, light in the visible light region is absorbed, and only blue light is reflected out of the system. Therefore, the morpho butterfly shines bright blue. It has been found that this morpho structure is similar in shape to a fine pattern having a standing wave effect in a semiconductor lithography process. We then report an attempt to fabricate morpho structures using lithographic techniques.
The snail shells have 200 nm porous structures, and an oil repellent function in water. Three biomimetic structures were fabricated: a silicon black surface, a silicon substrate having nano pillars, and a soft resin sheet having nano pillars. All these structures have equivalent sizes to the real snail shells, and showed good oil repellent effects. The latter two structures have regularly arranged pillars. The last resin sheet was fabricated by using a silicon mold with nano holes and using nanoimprint technologies. As this sheet is soft metamaterial, it can be processed to other shapes. As an example, a tube with oil repellent inner walls was fabricated and evaluated. Good oil repellent and antifouling effect were experimentally obtained from the water-oil mixture flow test. These results indicate the future advances in medical equipment and infrastructure.
Our group previously explored methods for measuring simulation parameter for advanced chemically amplified (CA) resists, including development parameters [1]. Dill's C parameter [2-3] , acid diffusion length generated from PAG [4], and de-protection reaction parameters [5-6]. We performed simulations of EUV resists using these parameters, the results of which allowed us to examine the conditions for reducing LER and improving resolution. This paper discusses a method for measuring the Dill's B parameter, which had been difficult to measure with conventional methods. We also confirmed that enhancing the resist polymer's EUV light absorption is effective in improving the sensitivity of the CA resist.
Novolak resists have been widely used in IC production and are used to this day in the production of flat panel displays (FPDs) and MEMS. However, with the advent of high-definition devices, FPDs must meet growing requirements for finer dimensions. These trends have generated requirements for higher sensitivity, higher resolution, and wider process margins for novolak resists. Using a lithography simulator with the goal of improving the performance of novolak resists, we examined various approaches to improving resist materials. This report discusses efforts to improve resolution and to broaden process margins using a novolak resin that exhibits a higher degree of fractionation than in the previous report (maximum fractionated resin) with the addition of low molecular weight phenol resins.
We evaluated standing-wave effects in photoresists with and without hexamethyldisilazane (HMDS), which improves adhesion of a photoresist to a Si-wafer substrate, using a resist development analyzer (RDA). The amplitude of a swing curve with HMDS was reduced around 9% compared to that without HMDS. Perhaps, this is considered a reduction of standing-wave effect in the photoresist attributable to an antireflection effect of an HMDS-photoresist mixed layer. The antireflection effect of the layer was evaluated by calculation using PROLITH. We demonstrated that the thickness, a refractive index and an extinction coefficient of the layer were, respectively, 10 nm, 1.60 and 0.5. Using HMDS can expect to improve dimensional stability by 1.17 times on the calculations.
Against the backdrop of remarkable strides in recent EUVL research, EUV chemically amplified resists were discussed as a critical issue in last year's International EUVL Symposium. Important concerns involving resists include improvements in resolution and sensitivity and reductions in outgassing and roughness. One important factor in improving resolution and sensitivity is understanding the behavior of the de-protection reaction of a photoresist during EUV exposures. We examined a system to analyze de-protection reactions in an ultra-thin-film process suitable for the EUV resist process.
Studies have been carried out on developing a method for improving EUV resist sensitivity by enhancing EUV light absorption through the addition of metals having high EUV light absorption to the resist polymer in order to increase secondary electron emission, thereby enhancing PAG reactivity and improving acid generation efficiency[1-3]. To confirm whether the addition of metals having high EUV light absorption actually does enhance sensitivity, study efforts included transmittance measurements and sensitivity evaluations of resist samples doped with ZrO2 or TeO2 nanoparticles, which have low and high EUV light absorption, respectively, in molar quantities of 0-2 relative to PAG. The samples were subjected to EUV exposure at the NewSUBARU synchrotron radiation facility. While the ZrO2-doped resist showed no evident enhancement of sensitivity or transmittance, the TeO2-doped resist showed enhancement in both properties. Based on these results, we confirmed that the addition of metals having high EUV light absorption to the EUV resist enhances its EUV light absorption and increases secondary electron emission, thereby enhancing PAG reactivity and improving acid generation efficiency.
