Article
Energy & Fuels
Yuqing Li, Hitoshi Sai, Takuya Matsui, Zhihao Xu, Van Hoang Nguyen, Yasuyoshi Kurokawa, Noritaka Usami
Summary: This article introduces a method to fabricate nanometer-sized pyramids and investigates their application in silicon solar cells. The experimental results demonstrate that Si nanopyramids have lower reflectance and smaller etching margin, which can improve the performance of the cells while maintaining excellent surface passivation and carrier transport properties.
Article
Chemistry, Physical
Theresa Bartschmid, Fedja J. Wendisch, Amin Farhadi, Gilles R. Bourret
Summary: Vertically aligned silicon nanowire arrays have remarkable optical properties that enhance light absorption and reduce light reflection, which is beneficial for improving solar cell design. Through chemical and electrochemical methods, we have successfully structured and patterned the nanowire arrays in three dimensions, achieving spatially controlled optical properties.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Christopher Schutzeichel, Nataliya Kiriy, Anton Kiriy, Brigitte Voit
Summary: This paper presents a novel microstructuring method that allows patterning of n-doped silicon substrates without the need for etch-masks or stencils. The method involves simple alkaline etching under illumination, controlled by p-doped micro-sized implants buried beneath the n-doped layer. The buried implants act as micro-sized photovoltaic cells, generating a flux of electrons to protect the silicon oxide layer from etching, ultimately leading to substrate microstructuring.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Chuhao Yao, Yue Zhao, Xiaomeng Zhang, Hailiang Li, Changqing Xie
Summary: A novel and facile scheme for fabricating highly uniform vertically aligned silicon nanowires (Si-NWs) arrays was presented, demonstrated numerically with excellent properties. The method involves fabricating thin gold (Au) nanostructures using magnetron sputtering followed by metal-assisted chemical etching at low temperature to achieve wafer-scale and highly uniform Si-NWs arrays. The Si-NWs arrays showed promising photoelectric conversion performance, with a maximum exciton generation rate of 1.76 x 10(24) and a reflectivity below 10% over a wide wavelength range at an annealing temperature of 200 degrees C.
RESULTS IN PHYSICS
(2021)
Article
Engineering, Electrical & Electronic
David Schmelz, Thomas Kasebier, Zhitian Shi, Qixiang Cheng, Natali Sergeev, Detlef Schelle, Uwe Zeitner
Summary: Valuable research on black silicon (b-Si) nanostructures has led to its increased application. However, existing research focuses on flat substrates. This study investigated b-Si structures on curved surfaces by fabricating them on hemispherical silicon lenses using inductively coupled plasma reactive ion etching. Different structure morphologies were achieved based on the etching parameters selected, similar to fabrication on Si wafers. Scanning electron microscopy inspections confirmed the homogeneity and orientation of the structures, while simulations explained the underlying etching process.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2023)
Article
Nanoscience & Nanotechnology
Maha Yusuf, George K. Herring, Lars Thorben Neustock, Mohammad Asif Zaman, Usha Raghuram, Vijay K. Narasimhan, Charmaine Chia, Roger T. Howe
Summary: High-contrast alignment marks are essential for precise alignment in X-ray imaging systems. The use of nanostructured black silicon (n-BSi) and optimized deep reactive-ion etching (DRIE) process allows for the fabrication of absorptive areas with low reflectance and high contrast ratio. Systematic variation of polymer deposition time T leads to various nanostructures, ultimately improving the efficiency and precision of alignment marks.
ACS APPLIED NANO MATERIALS
(2021)
Review
Optics
Andrey A. Bushunov, Mikhail K. Tarabrin, Vladimir A. Lazarev
Summary: This study provides a critical review of recent advances in microstructure fabrication technology for mid-infrared antireflection applications, highlighting the most promising techniques through detailed discussions of advantages and drawbacks of various methods.
LASER & PHOTONICS REVIEWS
(2021)
Article
Materials Science, Multidisciplinary
Nadzeya Khinevich, Mindaugas Juodenas, Asta Tamuleviciene, Hanna Bandarenka, Sigitas Tamulevicius
Summary: The study focused on the morphology and optical properties of porous silicon, with an emphasis on increasing pore density by removing bottleneck structures and its potential use as a template for nanoparticle arrays.
Article
Chemistry, Physical
Taito Yoshie, Kenji Ishikawa, Thi-Thuy-Nga Nguyen, Shih-Nan Hsiao, Takayoshi Tsutsumi, Makoto Sekine, Masaru Hori
Summary: In the fabrication of semiconductor devices, the feature profiles of high-aspect-ratio Si trenches need to be controlled considering aspect-ratio-dependent etching. This control is achieved by a cyclic process involving sustained Ar plasma, alternating injection of C4F8 and SF6, and short-period substrate bias supply. The transient behaviors of gaseous and surface reactions are currently revealed through measurement of plasma parameters using a surface wave probe and optical emission spectroscopy. By fluorinating the etched surface during the cycle and controlling the bias-supply timing, an ARDE-free Si trench feature profile can be fabricated.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Physical
A. Mohamedyaseen, P. Suresh Kumar, K. R. Kavitha, N. A. Vignesh
Summary: This study successfully developed thermoelectric generators using new fabrication methods and materials to power Internet of Things sensors. Different nano-manufacturing techniques can be utilized to produce nanostructures of diverse materials.
Article
Engineering, Electrical & Electronic
Tzu-Chieh Hong, Wen-Hsiang Lu, Yeong-Her Wang, Jiun-Yun Li, Yao-Jen Lee, Tien-Sheng Chao
Summary: Germanium-tin (GeSn) epitaxy layer was grown on an 8-inch SOI wafer with a Ge buffer layer. The etching rates of different solutions for the GeSn layer were investigated. The developed two-step etching process allows the selective etching of the Ge buffer and Si bottom layers, facilitating the fabrication of GeSn nanowires (NWs). GeSn NWFETs were successfully fabricated and the strain of the GeSn NW channels was preserved using the proposed optimized fabrication process.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Chemistry, Physical
Shih-Nan Hsiao, Kenji Ishikawa, Toshio Hayashi, Jiwei Ni, Takayoshi Tsutsumi, Makoto Sekine, Masaru Hori
Summary: Gas chemistry plays a significant role in etch selectivity in semiconductor device fabrication, enabling control over the etchant composition for atomic-scale removal and high-aspect ratio features. By experimenting and conducting quantum chemical calculations, the effects of CH2FCHF2 and O-2 mixtures on etch selectivity among SiN, SiO2, and poly-Si films were investigated, focusing on the composition of CHF2+ and CH2F+ ions and their reactions.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Analytical
David Schmelz, Guobin Jia, Thomas Kaesebier, Jonathan Plentz, Uwe Detlef Zeitner
Summary: This publication presents a possible fabrication process for antireflective (AR) nanostructures using colloidal polystyrene (PS) nanosphere lithography. The process allows for the creation of AR structures on curved fused silica substrates without being influenced by shape or material characteristics. Broadband AR structures with low losses were successfully fabricated on planar fused silica wafers and aspherical planoconvex lenses.
Article
Chemistry, Analytical
Chutiparn Lertvachirapaiboon, Naraphorn Tunghathaithip, Sukkaneste Tungasmita, Akira Baba, Kazunari Shinbo, Keizo Kato
Summary: This study presents a practical technique for determining the length of a silicon nanowire (SiNW) array using reflected images from a smartphone camera. The relationship between reflection spectrum and SiNW array length was investigated, showing an exponential increase in percent reflectance with increasing average length. Optical sensing was developed into a simple and practical method for detecting SiNW array lengths, demonstrating the potential for on-site characterization of reflective materials.
INSTRUMENTATION SCIENCE & TECHNOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Antonio Alessio Leonardi, Maria Jose Lo Faro, Maria Miritello, Paolo Musumeci, Francesco Priolo, Barbara Fazio, Alessia Irrera
Summary: The research on the flexibility of thin film metal-assisted chemical etching (MACE) for the fabrication of Si NWs is crucial for Si NW-based devices. It allows the production of differently doped Si NWs and even a longitudinal heterojunction p-n inside the same single wire, which has never been reported using thin metal film MACE. Additionally, fractal arrays of Si NWs can be fabricated without any type of mask, enabling the creation of controllable artificial fractals with other interesting elements in a cost-effective and microelectronics compatible approach.
