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- 摘要
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- 实验方案
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Applied Nanophotonics || Stimulated emission and lasing
摘要： Stimulated transitions in quantum systems represent the principal background for laser operation. Lasers play important roles in daily life and form a valuable part of photonics. Though the first lasers were supposed to have an impact on material processing owing to extreme energy concentration, currently the main applications of lasers are not based on high-energy abilities, but essentially on their compactness, cheapness, and efficiency. Optical communication, laser printers, and DVD players are the most common laser applications, and here semiconductor lasers are definitely unsurpassed. In this chapter we provide a brief introduction to the principles of laser operation and laser device engineering to emphasize where nanostructures can be useful and which components of lasers can be improved by means of nanophotonic solutions. Because of the scope of this book, a brief explanatory style is used which may confuse laser experts but at the same time may still appear complicated for newcomers. This chapter may appear complicated for readers not at all familiar with lasers, and in this case appropriate textbooks are suggested for further reading.
关键词： quantum systems,lasing,stimulated emission,optical gain,semiconductor lasers
更新于2025-09-09 09:28:46
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Creation of Two-Dimensional Electron Gas and Role of Surface Donors in III-N Metal-Oxide-Semiconductor High-Electron Mobility Transistors
摘要： The role of surface donors at the oxide/semiconductor interface of III-N metal-oxide-semiconductor (MOS) high-electron mobility transistors (HEMTs), by creating a two-dimensional electron gas (2DEG) and the device performance, are investigated. Al2O3/GaN/AlGaN/GaN MOS HEMTs show the surface donor density (Nd,surf ) of 2.2 (cid:1) 1013 cm(cid:3)2 which is increased up to 3.4 (cid:1) 1013 cm(cid:3)2 after post-deposition annealing. In the latter, surface donors fully compensate the surface polarization charge and the HEMT threshold voltage decreases substantially with the oxide thickness. On the other hand, an open-channel drain current is found to be independent of Nd,surf, while marginal trapping is completely removed when Nd,surf increases with annealing. Consequently, ionized surface donors behave like a fixed charge and are clearly distinguishable from trapping states. Open-channel 2DEG densities of (cid:4)1.1 (cid:1) 1013 cm(cid:3)2 are extracted from capacitance–voltage measurements. Similarly, recent data on enhancement-mode HfO2/InAlN/AlN/GaN MOS HEMTs are analyzed where Nd,surf is reduced down to (cid:3)2 while 2DEG densities reach (cid:4)2.7 (cid:1) 1013 cm(cid:3)2. It is suggested that under the open-channel condition, 2DEG is supplied also by an injecting source contact if Nd,surf is lower than the QW polarization charge. Our charge quantifications are supported by calculating energy-band diagrams.
关键词： oxide-semiconductor interfaces,AlGaN/GaN high-electron mobility transistors (HEMTs),polarization
更新于2025-09-09 09:28:46
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Nanoelectronics and Materials Development || Epitaxial Cu3Ge Thin Film: Fabrication, Structure, and Property
摘要： In this paper, the fabrication and electrical property characterization of epitaxial Cu3Ge thin film are performed. By adjusting deposition parameters, the crystallinity of the as‐grown Cu3Ge thin films is improved, with the formation of twins within it. The average work function of epitaxial Cu3Ge thin film is measured to be ～4.47 + 0.02 eV, render‐ ing it a desirable mid‐gap gate metal for applications in complementary metal‐oxide semiconductor (CMOS) devices. The present study therefore shows an epitaxial Cu3Ge thin film that is promising for applications.
关键词： sapphire,semiconductor metallization,Cu3Ge thin film,pulsed laser deposition,twin
更新于2025-09-09 09:28:46
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[Semiconductors and Semimetals] Semiconductor Nanowires I - Growth and Theory Volume 93 || Hybrid III–V/Silicon Nanowires
摘要： The success of the semiconductor industry originates from the ability to precisely tune the electronic properties of semiconductor materials. Different approaches are used to enhance the functionality of semiconductors, such as impurity doping, alloying, heterostructuring, and straining. All these methods are based on the addition of chemical elements to a pure semiconductor. An important example is the invention of the GaAs/AlGaAs heterostructure, which has enabled the development of laser diode and high-electron-mobility transistor (HEMT). In this chapter, we will discuss the combination of two different classes of semiconductors, group IV, like Si and Ge, and group III–V, like GaAs and InP. We will focus on a relatively new materials system, i.e., nanowires (NWs), in which strain can be effectively relieved at the surface due to the small dimensions, therefore relaxing the requirements on lattice matching. This system thus offers enhanced flexibility over the conventional layered structures in combining different semiconductor materials. These new combinations may boost the performance of already widely explored device concepts, such as transistors and solar cells, but may also open new applications, such as in quantum information technology. After a discussion on the different challenges related to the combination of Si and III–V semiconductors, we will discuss the growth of III–V nanowires on group IV substrates, and then focus on the growth of heterostructures within nanowires in the radial and axial directions.
关键词： silicon,III-V nanowires,semiconductor,epitaxial growth,heterostructures
更新于2025-09-09 09:28:46
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High Temperature Operation Limit Assessment for 4H-SiC Schottky Diode-based Extreme Temperature Sensors
摘要： We developed a simplified theoretical model for parameters calculation of diode temperature sensors (DTS) based on Schottky diodes (SD). The current flow mechanism of the diodes considered was dominated by over-barrier thermionic emission. Qualitative correlations between basic fundamental and electrophysical parameters of such DTS were established. The expressions for ultimate high-temperature parameters of the DTS were obtained. Theoretical results obtained were approved using test samples of DTS with Schottky contact Ni/n-SiC (4H). It was shown that physical high-temperature limit of operation of such a DTS (>1250 K) exceeded the values of commercial DTS based on Si, GaAs, AlGaAs p-n junctions. And the SD-based DTS itself demonstrated significantly lower energy consumption.
关键词： wide bandgap,thermal sensitivity,high temperature,Schottky diode,temperature sensor,semiconductor,thermal limit
更新于2025-09-09 09:28:46
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Nonreciprocal Optical and Magnetooptical Effects in Semiconductor Quantum Wells
摘要： Effects implying violation of the Fresnel light reflection laws in semiconductor structures with quantum wells (QWs) have been investigated. This violation is related to the manifestation of spatial dispersion caused by spin–orbit coupling in structures without inversion centers. The spin–orbit coupling constants characterizing polarization conversion in symmetric and asymmetric structures with QWs have been measured.
关键词： spatial dispersion,nonreciprocal optical effects,polarization conversion,spin–orbit coupling,semiconductor quantum wells,magnetooptical effects
更新于2025-09-09 09:28:46
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Solution-processed inorganic p-channel transistors: Recent advances and perspectives
摘要： For decades, inorganic n-type metal-oxide semiconductors have attracted great interest across a wide range of applications due to their excellent electrical property, low cost, high optical transparency, and good ambient stability. The next attention has focused on the development of high-performance p-type semiconductors with comparable opto/electric properties to n-type counterparts. This paper provides a comprehensive overview of recent progress in solution-processed inorganic p-type semiconductors that can be applied as channel layers in thin-?lm transistors and complementary metal-oxide semiconductor-based integrated circuits. We ?rst introduce conventional p-type oxide semiconductors and review their achievements on related devices. Then, we pay a speci?c focus on emerging (pseudo)halide materials for realization of transparent, low-temperature and high-performance printable electronics and circuits.
关键词： Inorganic p-type semiconductor,Low-temperature process,Solution process,Field-e?ect transistor,Printable electronics
更新于2025-09-09 09:28:46
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A method to discern voltage dependent internal photoemission component from photoconductivity content in spectral response of metal-organic semiconductor-metal devices and evaluate the interface barriers
摘要： The ability to detect and determine a typically weak internal photoemission (IPE) signal from a usually strong photoconductivity (PC) signal within a spectral response (SR) measurement can be helpful in studying the interface properties of metal-semiconductor junctions, which are often critical for proper design and analysis of semiconductor electronic devices including organic photovoltaic devices. In this report, we propose a method to discern the voltage dependent IPE component from PC content in a measured SR of organic devices. The method is based on the ratio of SR measured at different voltage bias conditions in metal-organic semiconductor-metal devices. The separated IPE component, hence, can be used to estimate the associated interface barrier(s). The differentiation between IPE and PC is probably caused due to the barrier changing at the metal and organic semiconductor interface on the application of bias which causes a modulation in IPE signal with the applied bias. In this work, a theoretical basis for the method of characterisation has been developed. Based on the analysis, as an example, the barriers between [6, 6] phenyl C61 butyric acid methyl ester (PCBM) and electrodes indium tin oxide and aluminium for different bias voltages have been evaluated. This simple and elegant method of studying metal and organic semiconductor barrier, when applicable, can be helpful in device design and characterisation.
关键词： Spectral Response,Metal-Semiconductor Barrier,Bias Dependent Spectral Response,Internal Photoemission
更新于2025-09-09 09:28:46
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Growth without Postannealing of Monoclinic VO2 Thin Film by Atomic Layer Deposition Using VCl4 as Precursor
摘要： Vanadium dioxide (VO2) is a multifunctional material with semiconductor-to-metal transition (SMT) property. Organic vanadium compounds are usually employed as ALD precursors to grow VO2 films. However, the as-deposited films are reported to have amorphous structure with no significant SMT property, therefore a postannealing process is necessary for converting the amorphous VO2 to crystalline VO2. In this study, an inorganic vanadium tetrachloride (VCl4) is used as an ALD precursor for the first time to grow VO2 films. The VO2 film is directly crystallized and grown on the substrate without any postannealing process. The VO2 film displays significant SMT behavior, which is verified by temperature-dependent Raman spectrometer and four-point-probing system. The results demonstrate that the VCl4 is suitably employed as a new ALD precursor to grow crystallized VO2 films. It can be reasonably imagined that the VCl4 can also be used to grow various directly crystallized vanadium oxides by controlling the ALD-process parameters.
关键词： vanadium tetrachloride,vanadium oxide,atomic layer deposition,semiconductor-to-metal transition,vanadium dioxide
更新于2025-09-09 09:28:46
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[IEEE 2017 International Conference on Optical Network Design and Modeling (ONDM) - Budapest (2017.5.15-2017.5.18)] 2017 International Conference on Optical Network Design and Modeling (ONDM) - Ultrafast InGaAs photoswitch for RF signal processing
摘要： Optical processing of radiofrequency signals is demonstrated in this communication using photoswitches made from nitrogen ion implanted InGaAs. The sampling device shows an ultrafast picosecond response time while activated by ultra-short optical pulses or modulated optical beam centered at the wavelength of 1.55 μm. The optoelectronic device is embedded in a microwave coplanar waveguide which has a high electrical bandwidth allowing to process signals in the 1-67 GHz band. We investigate the potentiality of this component to be used either in photonic assisted sampling for future analog-to-digital converters or in photonic assisted heterodyne detection of RF modulated carriers.
关键词： ion implanted InGaAs,photonic assisted data processing,radio over fiber,ultrafast electronics,Photoconductive sampling,heterodyne photomixer,metal-semiconductor-metal devices
更新于2025-09-09 09:28:46