germanium

This paper presents the test results for high-performance and high-uniformity waveguide silicon-based germanium (Ge) photodetectors (PDs) for the O band and C band. Both wafer-scale and chip-scale test results are provided. The fabricated lateral p - i - n (LPIN) PDs exhibit a responsivity of 0.97 A/W at a bias of -2 V , a bandwidth of 60 GHz, and a no-return-to-zero (NRZ) eye diagram rate of 53.125 Gb/s. Additionally, an average dark current of 22.4 nA was obtained in the vertical p - i - n (VPIN) PDs at -2 V by optimizing the doping process...

Polycrystalline Ge thin films have attracted considerable attention as potential materials for use in various electronic and optical devices. We recently developed a low-temperature solid-phase crystallization technology for a doped Ge layer and achieved the highest electron mobility in a polycrystalline Ge thin film. In this study, we investigated the effects of strain on the crystalline and electrical properties of n-type polycrystalline Ge layers. By inserting a GeOx interlayer directly under Ge and selecting substrates with different coefficients of thermal expansion, we modulated the strain in the polycrystalline Ge layer, ranging from approximately 0...

Understanding the electronic transport of metal-semiconductor heterojunctions is of utmost importance for a wide range of emerging nanoelectronic devices like adaptive transistors, biosensors, and quantum devices. Here, we provide a comparison and in-depth discussion of the investigated Schottky heterojunction devices based on Si and Ge nanowires contacted with pure single-crystal Al. Key for the fabrication of these devices is the selective solid-state metal-semiconductor exchange of Si and Ge nanowires into Al, delivering void-free, single-crystal Al contacts with flat Schottky junctions, distinct from the bulk counterparts...

Semiconductor devices used in radiation environment are more prone to degradation in device performance. Junctionless Tunnel Field Effect Transistor (JLTFET) is one of the most potential candidates which overcomes the short channel effects and fabrication difficulties. In this work, 20 nm JLTFET is proposed with Silicon in the drain/channel region whereas source uses different materials, Silicon Germanium (SiGe), Gallium Nitride (GaN), Gallium Arsenide (GaAs), Indium Arsenide (InAs). The device performance is examined by subjecting it to heavy ion radiation at a lower and higher dose of linear energy transfer (LET) values...

BACKGROUND: The immune dysregulation underlying inflammatory bowel disease (IBD) can start years before the diagnosis, but the role of triggering factors and environmental exposures during this period is still uncertain. METHODS: This single-center case-control study included asymptomatic subjects with an incidental diagnosis of IBD during the colorectal cancer screening program. Twenty-two minerals and 17 metals were determined at diagnosis in hair samples and compared 1:2 to healthy controls...

The global demand for radio frequency (RF) modules and components has grown exponentially in recent decades. RF switches are the essential unit in RF front-end and reconfigurable systems leading to the rapid development of novel and advanced switch technology. Germanium telluride (GeTe), as one of the Chalcogenide phase-change materials, has been applied as an RF switch due to its low insertion loss, high isolation, fast switching speed, and low power consumption in recent years. In this review, an in-depth exploration of GeTe film characterization is presented, followed by a comparison of the device structure of directly heated and indirectly heated RF phase-change switches (RFPCSs)...

This article reports the results of an investigation into the activity concentration of natural radionuclides in raw building materials for underground parking lots, together with the assessment of the radiation hazard for the public related to exposure to ionizing radiations. To this purpose, high-purity germanium (HPGe) γ-ray spectrometry was employed in order to quantify the average specific activity of 226 Ra, 232 Th, and 40 K natural radioisotopes. With the aim to assess any possible radiological health risk for the population, the absorbed γ-dose rate ( D ), the annual effective dose equivalent outdoor ( AEDEout ) and indoor ( AEDEin ), the activity concentration index ( I ), and the alpha index ( Iα ) were also estimated, resulting in values that were lower than the maximum recommended ones for humans...

This work focused on developing optical coatings for decorative applications that remain transparent in the radiofrequency range. To achieve this, a combination of dielectric material (silicon-aluminum nitride, SiAlNx ) and low-electrical-conductivity semiconductor material (germanium) was utilized. Germanium plays a crucial role in providing absorption in the visible spectrum, facilitating the design of coatings with various aesthetic appearances, while allowing for control over their transmittance. The optical properties of thin germanium layers were thoroughly characterized and leveraged to create multilayer designs with diverse aesthetic features...

Gel electrolytes for lithium-ion batteries continue to replace the organic liquid electrolytes in conventional batteries due to their advantages of being less prone to leakage and non-explosive and possessing a high modulus of elasticity. However, the development of gel electrolytes has been hindered by their generally low ionic conductivity at room temperature and high interfacial impedance with electrodes. In this paper, a poly (vinylidene fluoride)-hexafluoropropylene copolymer (PVdF-HFP) with a flexible structure, Li6 PS5 Cl (LPSCl) powder of the sulfur-silver-germanium ore type, and lithium perchlorate salt (LiClO4 ) were prepared into sulfide gel composite electrolyte films (GCEs) via a thermosetting process...

Chirality ( C ) is a fundamental property of objects, in terms of symmetry. It is extremely important to sense and distinguish chiral molecules in the fields of biochemistry, science, and medicine. Vibrational circular dichroism (VCD) spectroscopy, obtained from the differential absorption of left- and right- circularly polarized light (CPL) in the infrared range, is a promising technique for enantiomeric detection and separation. However, VCD signals are typically very weak for most small molecules. Dielectric metasurfaces are an emerging platform to enhance the sensitivity of VCD spectroscopy of chiral molecules via superchiral field manipulation...

Zero-valent intercalation of atomic metals into the van der Waals gap of layered materials can be used to tune their electronic, optical, thermal, and mechanical properties. Here, we report the impact of intercalating ∼3 atm percent of zero-valent copper into germanium sulfide (GeS). Advanced many-body calculations predict that copper introduces quasi-localized intermediate band states, and time-resolved THz spectroscopy studies demonstrate that those states have prominent effects on the photoconductivity of GeS...

Biodegradable nanomaterials can significantly improve the safety profile of nanomedicine. Germanium nanoparticles (Ge NPs) with a safe biodegradation pathway are developed as efficient photothermal converters for biomedical applications. Ge NPs synthesized by femtosecond-laser ablation in liquids rapidly dissolve in physiological-like environment through the oxidation mechanism. The biodegradation of Ge nanoparticles is preserved in tumor cells in vitro and in normal tissues in mice with a half-life as short as 3...

The carbonyl cluster compound [GeRu6 (CO)18 HI] is unique in regard to its structure and bonding with a GeRu6 cluster core, a planar GeRu4 HI unit, extensive multi-center bonding, and an aromatic ring current similar to benzene (9-10 nA T-1 ). The open-shell cluster core is a Ge-centered five-membered Ru4 (Ru2 ) ring with CO ligands and an additional H and I atom, each bridging two Ru atoms on opposite sides of the cluster core. The compound is prepared at 130 °C in a weakly-coordinating ionic liquid...

Despite exceptional optoelectronic properties and rapidly increasing efficiency of perovskite solar cells (PSCs), the issues of toxicity and device instability have hampered the commercialization of this renewable energy technology. Lead (Pb) being the main culprit creates major environmental risks and therefore must be replaced with a nontoxic material such as tin (Sn), germanium (Ge), etc. Moreover, replacing organic cations in the perovskite's ABX3 structure with inorganic ones like cesium (Cs) helps aid the stability issues...

Accurate measurements of photonuclear reaction cross sections are crucial for a number of applications, including radiation shielding design, absorbed dose calculations, reactor physics and engineering, nuclear safeguard and inspection, astrophysics, and nuclear medicine. Primarily motivated by the study of the production of selected radionuclides with high-energy photon beams (mainly 225 Ac, 47 Sc, and 67 Cu), we have established a methodology for the measurement of photonuclear reaction cross sections with the microtron accelerator available at the Swiss Federal Institute of Metrology (METAS)...

Planar tetracoordinate silicon, germanium, tin, and lead (ptSi/Ge/Sn/Pb) species are scarce and exotic. Here, we report a series of penta-atomic ptSi/Ge/Sn/Pb XB2 Bi2 (X = Si, Ge, Sn, Pb) clusters with 20 valence electrons (VEs). Ternary XB2 Bi2 (X = Si, Ge, Sn, Pb) clusters possess beautiful fan-shaped structures, with a Bi-B-B-Bi chain surrounding the central X core. The unbiased density functional theory (DFT) searches and high-level CCSD(T) calculations reveal that these ptSi/Ge/Sn/Pb species are the global minima on their potential energy surfaces...

Antimonene has attracted much attention due to its excellent characteristics of high carrier mobility, thermoelectric properties and high stability. It has great application prospects in Q-switched lasers, laser protection and spintronics. At present, the epitaxy growth of antimonene mainly depends on molecular beam epitaxy. We have successfully prepared antimonene films on silicon, germanium/silicon substrates for the first time using electron beam evaporation coating and studied the effects of the deposition rate and substrate on the preparation of antimonene; film characterization was performed via confocal microprobe Raman spectroscopy, via X-ray diffraction and using a scanning electron microscope...

This study elucidates the thermodynamic reaction mechanism of the GeCl4 hydrogen reduction process for Ge preparation. Five independent reactions in the Ge-Cl-H ternary system were identified, utilizing the phase law, mass conservation principles, and thermodynamic data, with H2 as the reducing agent. Additionally, the effects of the temperature, feed ratio, and pressure on the germanium deposition rate during the GeCl4 hydrogen reduction process were investigated, guided by these five reactions. The results indicate that, with fixed temperature and pressure, a higher feed ratio (nH2/nGeCl4) leads to an increased germanium deposition rate...

The aim of this study was to assess the potential health risks of radioactive elements and heavy metals ingested through the consumption of various types of tea imported to the Polish market (black, green, red, oolong and white). The concentrations [Bq/kg] of radionuclides (40 K, 137 Cs, 226 Ra, 210 Pb and 228 Th) in tea leaves before and after brewing were measured using γ-ray spectrometry with high-purity germanium (HPGe). The concentrations [mg/kg] of the studied elements (Fe, Cr, Cu, Mo, Al, Mn, Ni, P, V, Cd and Pb) were determined using a microwave-induced plasma optical emission spectrometer (MIP-OES)...

Epitaxial growth is a fundamental step required to create devices for the semiconductor industry, enabling different materials to be combined in layers with precise control of strain and defect structure. Patterning the growth substrate with a mask before performing epitaxial growth offers additional degrees of freedom to engineer the structure and hence function of the semiconductor device. Here, we demonstrate that conditions exist where such epitaxial lateral overgrowth can produce complex, three-dimensional structures that incorporate cavities of deterministic size...