Abstract As a more efficient alternative to the crystalline Si (c‐Si) cell whose performance is approaching its theoretical limit, perovskite (PVSK)/Si tandem solar cells (TSCs) are attracting attention from academia and industry. The tandem device, which can benefit from the maturity of the c‐Si cells and the high performance of the PVSK solar cell, has undergone tremendous development. The expectation for its commercialization is increasing as the device shows conversion efficiencies surpassing those of single‐junction solar cells. In this perspective article, the recent progress of the PVSK/Si TSC is summarized from a viewpoint balanced between academia and industry, by regrouping reported devices depending on the types of Si bottom cells: passivated emitter rear contact, heterojunction with intrinsic thin layer, and polysilicon‐passivated contact. In addition, opto‐electronic characterization methods of the PVSK/Si TSCs are reviewed, which can provide an in‐depth analysis of the subcells that can facilitate the development.

Abstract As a more efficient alternative to the crystalline Si (c‐Si) cell whose performance is approaching its theoretical limit, perovskite (PVSK)/Si tandem solar cells (TSCs) are attracting attention from academia and industry. The tandem device, which can benefit from the maturity of the c‐Si cells and the high performance of the PVSK solar cell, has undergone tremendous development. The expectation for its commercialization is increasing as the device shows conversion efficiencies surpassing those of single‐junction solar cells. In this perspective article, the recent progress of the PVSK/Si TSC is summarized from a viewpoint balanced between academia and industry, by regrouping reported devices depending on the types of Si bottom cells: passivated emitter rear contact, heterojunction with intrinsic thin layer, and polysilicon‐passivated contact. In addition, opto‐electronic characterization methods of the PVSK/Si TSCs are reviewed, which can provide an in‐depth analysis of the subcells that can facilitate the development.

Tandem Solar Cells As a more efficient alternative to the crystalline Si solar cell, the perovskite/Si tandem solar cell is attracting attention. In article 2201006, Ki Hong Kim, Jin Young Kim, and co-workers summarize the progress of the PVSK/Si tandem solar cell depending on the types of Si bottom cells: passivated emitter rear contact, heterojunction with intrinsic thin layer, and polysilicon-passivated contact.

Pathological hip fractures are associated with substantial morbidity and functional decline. We report a rare case of localized dialysis-related amyloidosis involving both hip joints. A 48-year-old man undergoing long-term hemodialysis presented with atraumatic right hip pain. Radiographs and magnetic resonance imaging revealed a pathological subcapital fracture of the right femoral neck and extensive bilateral femoral neck osteolysis, with amyloid deposition showing low signal intensity on T1-weighted images and high signal intensity on T2-weighted images. Given the severe bone erosion and impending fracture of the left femoral neck, bilateral total hip arthroplasty was performed. No evidence of systemic amyloidosis or plasma cell dyscrasia was identified. At one-year follow-up, the patient showed no postoperative complications and regained independent ambulation. This case represents the first reported Korean case of localized dialysis-related amyloidosis affecting both hip joints.

Herein, we present a novel analysis framework for grain size profile of ferroelectric hafnia to tackle critical shortcomings inherent in the current microstructural analysis. We vastly enhanced visibility of grains with ion beam treatment and performed accurate grain segmentation using deep neural network (DNN). By leveraging our new method, we discovered unexpected discrepancies that contradict previous results, such as deposition temperature (Tdep) and post-metallization annealing (PMA) dependence of grain size statistics, prompting us to reassess earlier interpretations. Combining microstructural analysis with electrical tests, we found that grain size reduction had both positive and negative outcomes: it caused significant diminishing of die-to-die variation (~68 % decrease in standard deviation) in coercive field (Ec), while triggering an upsurge in leakage current. These uncovered results signify robustness of our method in characterization of ferroelectric hafnia for in-depth examination of both device variability and reliability.

Preoperative planning using 3D prototyping pelvic models resulted in accurate cup positioning and stable outcomes in complex THA cases. Further studies with larger cohorts and longer follow-up are necessary to confirm these findings.

We present a ferroelectric NAND (FENAND) design that steepens the incremental step pulse programming (ISPP) slope and enhances reliability via a laminated FE stack. The laminate incorporates a 3 Å Al<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>O<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> interlayer at the mid-plane of a 15 nm HfZrO2 film. This structural modification reshapes the polarization-voltage loop, yielding a 25 % increase in coercive voltage (<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V_C</i>) and a 19 % reduction in remnant polarization (<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P_r</i>). Consequently, the ISPP slope improved by 16 %. The improvement stems from two effects: (1) Before switching, higher <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V_C</i> delays FE reversal, allowing more program voltage (<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V_PGM</i>) to drop across the gate insulator (G.IL), strengthening the field and boosting gate-side injection. (2) After switching, reduced <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P_r</i> lowers the compensation charge at the channel interface, suppressing channel-side injection. Lowering charge injection through channel insulator (Ch.IL) during write, without sacrificing memory window (MW), mitigates dielectric stress, achieving 10-year retention and endurance up to 10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> cycles. This FE stack design provides practical guidelines for scaling <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V_PGM</i> and spacer dimensions in high-density 3D FENAND.

We demonstrated a novel Ferroelectric Field-Effect Transistor (FeFET) with an IGZO channel, featuring a record-high memory window (MW) of up to 17.8V. A significant advancement is achieved by two strategies. Firstly, the introduction of an intermediate oxygen-deficient channel, which offers sufficient depletion charge to ensure full-loop polarization switching. Secondly, inserting a thin gate interlayer (G.IL), which further increases the MW by the contribution of injected charge through G.IL. With a sub-12nm gate stack thickness and an operation voltage below 15V, the device exhibits promising potential for high-density, low-power non-volatile memory applications.

항산화성과 단백질 흡착 억제능이 극대화된 기능성 아크릴 하이드로젤 콘택트렌즈는 부작용 없이 장시간 착용이 가능하기 때문에 최근 많은 관심을 받고 있다. 본 연구에서는 포스포릴콜린 고분자와 천연 폴리페놀인 에피갈로카테킨 갈레이트(EGCG)로 렌즈 표면을 코팅함에 의해서 항산화성과 단백질 흡착 억제능이 극대화된 아크릴 하이드로젤 콘택트렌즈인 MPC2EG 및 MPC4EG를 제조하였다. 제조된 콘택트렌즈는 높은 광학 투명도를 보였으며, 코팅 처리하지 않은 PHEMA 렌즈 대비 높은 산소투과율과 청색광 차단율을 보였다. 또한 여러 종류의 라디칼에 대해서 매우 뛰어난 라디칼 제거능을 보였고, 다양한 단백질에 대해서는 우수한 단백질 흡착 억제능을 보였다. 특히 감염성 안질환 원인균인 포도상구균과 대표적인 그램 음성균인 대장균에 대해서 매우 우수한 항균성을 보였다.