- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Epitaxial Ge-rich silicon layers after dry oxidation of Ge implanted silicon
摘要： We report on formation of epi-layer of SixGe1-x by taking standard procedure in CMOS technology. The competitive process of solid solubility of Ge dopant into Si and SiO2 is the key to engineer atomically sharp, low defect very thin epitaxial layer at the interface of oxide-Si. Oxidation time process was used to control the distribution of the doped Ge ions at the interface of Si with oxide and in the oxide layer. Implanted samples (35 keV and 1 × 1016 Ge+/cm2) were oxidized at 1050 °C for 30–90 min. RBS-Channeling analysis shows two separate peaks of Ge corresponds to different depths after oxidation. Corroborate with high resolution microscopy and elemental analysis, we determined the first peak as enriched layer of SixGe1-x at the interface of SiO2eSi. Less than 10 nm epitaxially grown interfacial layer is very low in defects, and Ge ions are fully substituted into the host lattice. The second peak originated from diffusion of Ge into SiO2 resulted in a segregated layer containing Ge in oxide film. Technological demand on forming SixGe1-x layer for CMOS application through standard routes is what we address in this research.
关键词： High resolution electron microscopy,Point defects,Germanium silicon alloys,Ion implantation,Solid phase epitaxy
更新于2025-09-09 09:28:46
-
Epitaxial growth of Sb-doped Ge layers on ferromagnetic Fe <sub/>3</sub> Si for vertical semiconductor spintronic devices
摘要： By combining solid phase epitaxy and molecular beam epitaxy with Sb doping, we can form n-type Ge layers on one of the ferromagnetic Heusler alloys, Fe3Si. Two-dimensional epitaxial growth of the Sb-doped Ge layers can be achieved on the Si-terminated Fe3Si surface at 175 ?C. Electrical properties of the Au-Ti/Sb-doped Ge/Fe3Si/p-Ge/Al vertical devices indicate that the Sb-doped Ge layer is an n-type semiconductor. We also show a high-quality CoFe/n-Ge/Fe3Si trilayer structure for vertical semiconductor spintronic devices.
关键词： germanium,solid phase epitaxy,molecular beam epitaxy,spintronics
更新于2025-09-09 09:28:46
-
[IEEE 2018 48th European Microwave Conference (EuMC) - Madrid, Spain (2018.9.23-2018.9.27)] 2018 48th European Microwave Conference (EuMC) - Characterization of Phase Change Material Germanium Telluride for RF Switches
摘要： This paper presents the simulation and measured results of a phase-change material (PCM) based radio-frequency (RF) switch optimized to improve the ratio between OFF-state and ON-state resistivity. Various samples having germanium telluride (GeTe) films are developed and imaged using Atomic Force Microscope (AFM) and are compared with cross-wafer resistance measurement results to determine the optimum sputtering conditions of the GeTe films. A simple four-layer fabrication process for GeTe based switches is presented. Several switches with different micro-heater dimensions are compared to investigate the performance of heater and its impact on the isolation performance of switch. A compact RF series switch has been measured, demonstrating an insertion loss of only 0.29 dB and an OFF-state isolation better than 23 dB over DC–26 GHz frequency range, yielding a relatively high Roff/Ron ratio.
关键词： SPST,Latching RF Switches,Phase Change Material (PCM),RF Switch,Germanium Telluride (GeTe)
更新于2025-09-04 15:30:14
-
Suppression of segregation of the phosphorus δ-doping layer in germanium by incorporation of carbon
摘要： The successful formation of abrupt phosphorus (P) δ-doping profiles in germanium (Ge) is reported. When the P δ-doping layers were grown by molecular beam epitaxy (MBE) directly on Ge wafers whose surfaces had residual carbon impurities, more than a half the phosphorus atoms were confined successfully within a few nm of the initial doping position even after the growth of Ge capping layers on the top. On the other hand, the same P layers grown on Ge buffer layers that had much less carbon showed significantly broadened P concentration profiles. Current–voltage characteristics of Au/Ti/Ge capping/P δ-doping/n-Ge structures having the abrupt P δ-doping layers with carbon assistance showed excellent ohmic behaviors when P doses were higher than 1 × 1014 cm?2 and the capping layer thickness was as thin as 5 nm. Therefore, the insertion of carbon around the P doping layer is a useful way of realizing ultrashallow junctions in Ge.
关键词： germanium,carbon incorporation,molecular beam epitaxy,ohmic contacts,phosphorus δ-doping
更新于2025-09-04 15:30:14
-
Hydrogen intercalation of CVD graphene on Germanium (001) – strain and doping analysis using Raman spectroscopy
摘要： We report a study of structural properties of graphene grown on germanium (001) when subjected to hydrogen intercalation during cooling, using chemical vapor deposition method. The systematic statistical analysis of the Raman spectra indicated that hydrogen increased the number of structural defects in graphene and caused the increase of the compressive strain. Interestingly, it was also found that hydrogen impacted on charge doping. This findings offer a new insight into the nature of graphene-germanium interaction and constitutes an important step towards graphene integration into modern electronics.
关键词： hydrogen intercalation,raman spectroscopy,graphene on germanium
更新于2025-09-04 15:30:14
-
High germanium doping of GaN films by ammonia molecular beam epitaxy
摘要： Doping Gallium nitride (GaN) with elemental Germanium (Ge) grown by ammonia molecular beam epitaxy is presented. Growth studies varying the GaN growth rate, substrate growth temperature and the elemental Ge flux reveal several incorporation dependencies. Ge incorporation increases with flux, as expected, and a doping range from ~1017 cm-3 to 1020 cm-3 was readily achieved. A strong substrate temperature dependence on the electrical properties of films grown is observed, with an optimal growth temperature of 740 °C, lower than standard GaN growth conditions for the ammonia molecular beam epitaxy. Compensation effects at higher growth temperatures are suspected, as observed with other techniques. Crystallographic defects are apparent at the highest doping concentrations from electrical and optical measurements, however thin layers of such highly doped films are of great interest for contact layers and tunnel junctions in devices.
关键词： Ammonia Molecular Beam Epitaxy,Molecular Beam Epitaxy,Tunnel Junctions,Germanium Doping,Gallium Nitride
更新于2025-09-04 15:30:14
-
[IEEE 2018 IEEE International Symposium on the Physical and Failure Analysis of Integrated Circuits (IPFA) - Singapore (2018.7.16-2018.7.19)] 2018 IEEE International Symposium on the Physical and Failure Analysis of Integrated Circuits (IPFA) - Characterization of Bandgap Engineering on Operative Transistor Devices by Spectral Photon Emission
摘要： In modern IC technologies, it is very common to use germanium enriched silicon in order to increase field effect transistor (FET) channel carrier mobility for high performance. The germanium content modifies the effective semiconductor band gap EG. Thus, the bandgap energy EG is an important technology performance parameter. EG can be obtained in an LED-like operation of electronic devices, requiring forward biased p-n junctions. P-n junctions in FETs are source or drain to body diodes, usually grounded or reversely biased. This investigation applies a bias to the body that can trigger parasitic forward operation of the source/drain to body p-n junction in any FET. Spectral photon emission (SPE) is taken here as non-destructive in operative method to characterize engineered bandgaps transistor devices, while the device remains fully functional. Proving this technique with the nominal silicon bandgap on an (unstrained) 120nm technology FET, the characterization capability for bandgap engineering is successfully demonstrated using SiGe:C HBT. In IC technology, Ge enriched silicon is recently often used to increase channel carrier mobility. As a next step, 14/16nm p-type FinFET devices have been investigated by applying a bias voltage to the body and thereby activating one of the body/diffusion p-n junctions in forward bias. By measuring the spectral distribution of emission intensity through the backside of the operating device with an InGaAs detector, EG of the engineered bandgap can be determined in the FinFETs as well, in case of the investigated p-type FinFETs to 0.84 eV. This opens a new path for contactless fault isolation by quantitative local determination of bandgap engineering.
关键词： Bandgap engineering,body diode,heterojunction bipolar transistor,body bias voltage,contactless fault isolation,parasitic operation,FinFET,germanium,MOSFET,p-n junction,bandgap characterization,spectral photon emission,SiGe,HBT
更新于2025-09-04 15:30:14
-
Development of a ReaxFF Reactive Force Field for Interstitial Oxygen in Germanium and Its Application to GeO <sub/>2</sub> /Ge Interfaces
摘要： We developed the ReaxFF force field parameters for Ge/O/H interactions, specifically targeted for the applications of Ge/GeO2 interfaces and O-diffusion in bulk Ge. The original training set, taken from the Zheng et al. work includes Quantum Mechanics (QM) data for equations of state and heats of formation of GeO and GeO2 condensed phases as well as dissociation energies for single and double bonds of Ge and angle distortion of O-Ge-O. We expanded this training set with the additional crystal data containing the formation energies of different O-interstitial centers and the minimum energy migration pathway of O atom in diamond Ge. After refitting the force field parameters based upon the extended training set, the ReaxFF results that the equations of state and heats of formation of the GeO and GeO2 condensed phases retain a good fit with the QM calculations. In addition, the ReaxFF correctly predicts the relative stability of the O-interstitial centers in the diamond Ge to be bond-center → split → tetrahedral → hexagonal from most stable to least stable with the energies showing quantitatively agreement with DFT. Furthermore, O atoms diffuse along a pathway between neighboring bond-centered interstitial sites and go through the asymmetric transition state at the split site as in DFT. We also examined the temperature dependence of O diffusion in bulk Ge, and subjected the GeO2/Ge interface to heat treatment based on the ReaxFF and Tersoff potential. On the basis of our MD results, the ReaxFF accurately predicts the diffusion barrier value as 50.02 kcal/mol within the temperature range of [800-2000K]. At the temperatures over 1400 K, ReaxFF allows the O atom to diffuse along the theoretically reported pathway between the adjacent BC centers whereas Tersoff potential contradicts the DFT reports by resulting a diffusion between the BC and H interstitial sites. For the Ge/GeO2 interface, the ReaxFF results that the thickness of GeO2 increases and the Ge substrate is consumed depending on the temperature and the oxidation time, supported by the experiments, while no change was observed in the thicknesses of Ge substrate and GeO2 slab in the Tersoff based simulations.
关键词： Oxygen diffusion,GeO2/Ge interface,Molecular dynamics,Germanium,ReaxFF
更新于2025-09-04 15:30:14