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Abstract Ferroelectric field‐effect transistors (FeFETs) are increasingly important for in‐memory computing and monolithic 3D (M3D) integration in system‐on‐chip (SoC) applications. However, the high‐temperature processing required by most ferroelectric memories can lead to thermal damage to the underlying device layers, which poses significant physical limitations for 3D integration processes. To solve this problem, the study proposes using a nanosecond pulsed laser for selective annealing of hafnia‐based FeFETs, enabling precise control of heat penetration depth within thin films. Sufficient thermal energy is delivered to the IGZO oxide channel and HZO ferroelectric gate oxide without causing thermal damage to the bottom layer, which has a low transition temperature ( 106, retention > 106 s) are achieved in the ferroelectric HZO film. The resulting FeFET exhibited a wide memory window (>1.7 V) with a high on/off ratio (>105). In addition, moderate ferroelectric properties (2·Pr of 14.7 µC cm−2) and pattern recognition rate‐based linearity (potentiation: 1.13, depression: 1.6) are obtained. These results demonstrate compatibility in HZO FeFETs by specific laser annealing control and thin‐film layer design for various structures (3D integrated, flexible) with neuromorphic applications.

Background : The Donation Improvement Program (DIP) is intended to increase organ donation at hospitals. The program includes education for healthcare professionals of participating hospitals about each step of donation as well as evaluation. The DIP consists of medical record review (MRR) and a Hospital Attitude Survey (HAS). The purpose of this study was to evaluate the DIP results for the last 7 years. Methods : For MRR, we analyzed 58,385 cases of mortality from 77 hospitals between 2012 and 2018. The HAS data for the degree of education experience, competence, and knowledge related to brain death (BD) and donation were analyzed from 23 DIP-participating hospitals in 2012 and 51 DIP-participating hospitals in 2015 and 2018 each. Results : The recognition rate of potential BD was 24.9%, 61.3%, and 73.2%, and donation rate was 7.5%, 11.7%, and 15.8% at 6 months before, 1–2 years after, and 4–5 years after the agreement, respectively. Hospital staff with the necessary competence or knowledge to explain BD constituted 44.0% in 2012, while this increased to 62.8% in 2018. Conclusions: The DIP could increase the recognition of BD and the organ donation rate, and positively affect the attitudes of healthcare professionals toward organ donation. Spreading the DIP to all hospitals is urgent to increase organ donation.

Abstract The vertical thin film transistor (VTFT) has several advantages over the planar thin film transistor, such as a high current density and low operating voltage, because of the structural specificity. However, it is difficult to realize transistor operation in a VTFT because of the structural limitation that the gate field is blocked. As a solution, the conductivity modulation of a graphene electrode is studied with a micro‐hole structure as a gate field transfer electrode. The micro‐hole array pattern in the graphene allows better penetration of the gate field to junction and the work function to be modulated. Moreover, the patterning induces a doping effect on the graphene which results in a high barrier at the p–n junction and improves the conductivity in the device operation. The optimum performance is shown at 5 µm hole size and 30% hole ratio by analyzing the hole size and the area ratio. The proposed structure shows about 20 times higher on‐current than a planar transistor with a same active area. Compared to a VTFT using simple graphene working function modulation, the proposed structure has an on‐state current that is ten times higher and off‐state current that is reduced 50%, and therefore has an improved on–off ratio.

Abstract Micro size antennas have significant merits due to the small size effect, enabling new device concepts. However, the low‐quality factor (Q‐factor), the large size of impedance matching components, and the poor selectivity of the multi‐array design remain challenging issues. To solve these issues, a floating coil structure stacked on a loop micro‐antenna is suggested. Various floating coil designs are prepared with appropriate matching conditions at specific target frequencies, using an easy fabrication process without the need for additional space. A simple one‐loop antenna design shows a higher Q‐factor than other, more complicated designs. The micro‐sized loop antenna with the 80 µm trace width design exhibits the highest Q‐factor, around 31 within 7 GHz. The 8 different floating coil designs result in high‐frequency selectivity from 1 to 7 GHz. The highest selectivity contrast and WPT efficiency are above 7 and around 1%, respectively. Considering the size of the antenna, the efficiency is not low, mainly due to the good matching effect with the high Q‐factor of the floating coil and the loop antenna. This micro‐antenna array concept with high integration density can be applied for advanced wireless neural stimulation or in wireless pixel array concepts in flexible displays.