- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Progress in metal organic cluster EUV photoresists
摘要： Most advanced microelectronic devices are made by using 193 nm immersion lithography systems, but it is difficult to follow the rapid development of semiconductors due to their approaching physical limits. Extreme ultraviolet (EUV) lithography which uses a shorter wavelength (i.e., 13.5 nm) light source can offer a way to print features under a 20 nm HP. EUV lithography requires photoresists that utilize EUV photons because photons generated by EUV exposure are fewer than photons generated by 193 nm light exposure. In this paper, our recent progress in metal oxide photoresist research will be discussed.
关键词： nanotechnology,lithography,semiconductor,EUV photoresists,metal organic cluster
更新于2025-09-04 15:30:14
-
Nonlinear absorption and Optical limiting of Ag–CdSe nano-hybrids of different growth times
摘要： Metal-semiconductor Nano-composites have enormous applications due to Plasmon –exciton coupling. Open aperture Z-scan is investigated for Ag–CdSe hybrid nanostructure, a toggle from saturable absorption process SA to reverse saturable absorption RSA is observed upon laser power increment. Proofs of crystal and morphological structure are given by selected area electron diffraction (SAED) and high resolution transmission electron microscope (HRTEM). Red shifting in photoluminescence spectra PL is observed which is ascribed to the particle size increment. Intriguing nonlinear findings can be used to engineer optical switching devices and optical limiters.
关键词： Photoluminescence,Open aperture Z scan,Ag:CdSe,Metal semiconductor nanohyrid structure,Optical limiting,Nonlinear absorption coefficient
更新于2025-09-04 15:30:14
-
Photon Noise Suppression by a Built-in Feedback Loop
摘要： Visionary quantum photonic networks need transform-limited single photons on demand. Resonance fluorescence on a quantum dot provides the access to a solid-state single photon source, where the environment is unfortunately the source of spin and charge noise that leads to fluctuations of the emission frequency and destroys the needed indistinguishability. We demonstrate a built-in stabilization approach for the photon stream, which relies solely on charge carrier dynamics of a two-dimensional hole gas inside a micropillar structure. The hole gas is fed by hole tunneling from field-ionized excitons and influences the energetic position of the excitonic transition by changing the local electric field at the position of the quantum dot. The standard deviation of the photon noise is suppressed by nearly 50% (noise power reduction of 6 dB) and it works in the developed micropillar structure for frequencies up to 1 kHz. This built-in feedback loop represents an easy way for photon noise suppression in large arrays of single photon emitters and promises to reach higher bandwidth by device optimization.
关键词： semiconductor heterostructure,single photon source,two-dimensional hole gas,Quantum dots,quantum optics,resonance fluorescence
更新于2025-09-04 15:30:14
-
Number series of atoms, interatomic bonds and interface bonds defining zinc-blende nanocrystals as function of size, shape and surface orientation: Analytic tools to interpret solid state spectroscopy data
摘要： Semiconductor nanocrystals (NCs) experience stress and charge transfer by embedding materials or ligands and impurity atoms. In return, the environment of NCs experiences a NC stress response which may lead to matrix deformation and propagated strain. Up to now, there is no universal gauge to evaluate the stress impact on NCs and their response as a function of NC size dNC. I deduce geometrical number series as analytical tools to obtain the number of NC atoms NNC(dNC[i]), bonds between NC atoms Nbnd(dNC[i]) and interface bonds NIF(dNC[i]) for seven high symmetry zinc-blende (zb) NCs with low-index faceting: {001} cubes, {111} octahedra, {110} dodecahedra, {001}-{111} pyramids, {111} tetrahedra, {111}-{001} quatrodecahedra and {001}-{111} quadrodecahedra. The fundamental insights into NC structures revealed here allow for major advancements in data interpretation and understanding of zb- and diamond-lattice based nanomaterials. The analytical number series can serve as a standard procedure for stress evaluation in solid state spectroscopy due to their deterministic nature, easy use and general applicability over a wide range of spectroscopy methods as well as NC sizes, forms and materials.
关键词： solid state spectroscopy,analytical number series,semiconductor nanocrystals,zinc-blende nanocrystals,stress evaluation
更新于2025-09-04 15:30:14
-
Research on Time Jitter of GaAs Photoconductive Semiconductor Switches in the Negative Differential Mobility Region
摘要： Time jitter of GaAs photoconductive semiconductor switches (PCSS) is investigated at an optical excitation of 1053 nm wavelength and 500 ps pulse duration. The experimental results indicate that the time jitter of the GaAs PCSS exhibits a nonmonotonic variation in negative differential mobility (NDM) region. All of these time jitters are lower than the 4% of the rise time of the switching waveform. The optimum time jitter of ~15 ps is achieved at the onset of the NDM region. The theoretical relationship between the optical excitation parameters, the bias electric field and the time jitter of the GaAs PCSS are built up. The nonmonotonic behavior of the time jitter with electric field is attributed to the instability of the relative fluctuation of drift velocity caused by inter-valley transition of carriers in GaAs.
关键词： inter-valley transition of carriers,photoconductive semiconductor switches,gallium arsenide (GaAs),negative differential mobility (NDM),time jitter
更新于2025-09-04 15:30:14
-
Electric field modified Arrhenius description of charge transport in amorphous oxide semiconductor thin film transistors
摘要： While it is known that the charge-carrier mobility in amorphous metal oxide semiconductor thin ?lm transistors (TFT) deviates from Arrhenius temperature dependence, we found that the Hall mobility measured in amorphous In-Ga-Zn-O (a-IGZO) follows an Arrhenius relation surprisingly well. We explain these observations by the effect of strong vertical electric ?eld created by the gate voltage, which facilitates direct tunneling of trapped carriers into the conductive band and leads to virtually temperature independent mobility. We present a generalized Arrhenius model based on the effective temperature concept. We show that our model allows quantitative description of the temperature dependence of the mobility in a-IGZO TFTs over a broad temperature range.
关键词： charge transport,thin film transistors,Arrhenius relation,amorphous oxide semiconductor,electric field
更新于2025-09-04 15:30:14
-
[IEEE 2018 IEEE 6th Workshop on Wide Bandgap Power Devices and Applications (WiPDA) - Atlanta, GA, USA (2018.10.31-2018.11.2)] 2018 IEEE 6th Workshop on Wide Bandgap Power Devices and Applications (WiPDA) - Instabilities by Parasitic Substrate-Loop of GaN-on-Si HEMTs in Half-Bridges
摘要： The stability of GaN-on-Si HEMTs with substrate-to-source termination is analyzed in a high-voltage half-bridge. The work exposes that external substrate termination creates a parasitic substrate loop, which leads to unstable switching behavior under certain conditions. Stability analysis reveals that parasitic inductance in the substrate-loop alone is sufficient for instabilities, even with zero parasitic inductance in the gate- and power-loops. A systematic analytical stability analysis is carried out based on a small-signal equivalent circuit. The theory is verified by measurements using a PCB-embedded 600 V GaN HEMT with integrated gate driver. Adequate damping of the substrate loop resonance enables stable operation of the half-bridge module.
关键词： Semiconductor Device Packaging,Gallium Nitride,Switching Circuits,Circuit Stability,Substrate Potential,Bridge Circuits
更新于2025-09-04 15:30:14
-
[IEEE 2018 IEEE 14th International Conference on Automation Science and Engineering (CASE) - Munich, Germany (2018.8.20-2018.8.24)] 2018 IEEE 14th International Conference on Automation Science and Engineering (CASE) - Simulation-based Performance Assessment of Tool Requalification Strategies in Wafer Fabs
摘要： In this paper, we discuss requalification strategies for stepper tools in semiconductor wafer fabrication facilities (wafer fabs). Before processing lots on steppers, the steppers have to be qualified. A mathematical programming formulation is used periodically to determine appropriate qualification plans. These plans will be implemented at the shop-floor. Dur-ing consecutive planning epochs, certain already established qualifications of steppers can be canceled, for instance, due to stepper breakdowns. We study the performance of several re-qualification strategies in this situation. Therefore, we use a discrete-event simulation framework that allows for applying the mathematical programming formulation in a rolling hori-zon manner and for performing the requalification strategies while the production is executed in the simulation. We demon-strate by designed simulation experiments that some of the pro-posed strategies perform well with respect to throughput and cycle time while requiring only a low additional qualification effort.
关键词： semiconductor wafer fabrication,mathematical programming,discrete-event simulation,requalification strategies,stepper tools
更新于2025-09-04 15:30:14
-
[IEEE 2018 20th International Conference on Transparent Optical Networks (ICTON) - Bucharest (2018.7.1-2018.7.5)] 2018 20th International Conference on Transparent Optical Networks (ICTON) - Multi-Section Semiconductor Optical Amplifiers for Data Centre Networks
摘要： The ever-growing Internet based services and applications, involving a huge amount of computing and storage resources, have been powered by data centres (DC) [1]. The storage and movement of data within the DCs is driving the requirement for cost-effective, higher capacity inter- and intra- next generation DC networks [2]. Within the context of these next generation DC networks, the ability to transmit very high data rates (100 – 400 Gb/s) over both short and long distances (intra or inter DC fibre links) is one of the main challenges (within the optical sector. The modulation format that is currently touted as the most suitable for such high capacities is 4-level pulse amplitude modulation (PAM4), which carries 2 bits per symbol. Optical amplification is needed for reach extension for inter- and intra- DC communications, Semiconductor optical amplifiers (SOAs) are needed to realize a low cost amplification solution. SOAs possess many advantages, including low power consumption, small footprint, wide bandwidth, being integrateable, and the ability to accommodate wavelength ranges beyond the scope of Erbium doped fibre amplifiers. However, the use of SOAs for linear amplification of C-band optical signals is still relatively limited, mainly due to the relatively large noise figure (NF) associated with them compared to erbium doped fiber amplifiers and low saturation powers of about 10 mW. Multi-section SOAs are known to possess superior NFs and larger saturation powers than an equivalent single-section SOA [3], and hence may provide performance benefit for reach extension for DC networks. In this work, we examine the use of a multi-section semiconductor optical amplifier (MS-SOA) [3] to provide an improvement in its use as a linear amplifier compared to a single section SOA. The MS-SOAs have been shown to have superior noise and linearity performance compared with single section SOAs. We configure the MS-SOA to operate in the low-NF mode with high saturation power mode and the equivalent single-section SOA. We compare the input power dynamic range for the MS-SOA and equivalent single-section SOA. We expect an improvement in the input power dynamic range of at least 3 dB [4]. The combination of a lower NF and higher saturation power enables crosstalk-free amplification of simultaneous multi-wavelength channels using the same SOA device.
关键词： multi-section semiconductor optical amplifier,advanced modulation formats,data centre networks
更新于2025-09-04 15:30:14
-
Lack of correlation between C-V hysteresis and capacitance frequency dispersion in accumulation of metal gate/high- <i>k</i> /n-InGaAs metal-oxide-semiconductor stacks
摘要： The correlation between capacitance-voltage hysteresis and accumulation capacitance frequency dispersion of metal gate/high-k/n-InGaAs metal-oxide-semiconductor stacks is experimentally assessed. Samples fabricated employing forming gas annealing (FGA) or substrate air exposure to obtain different densities of defects were thoroughly characterized and the results were compared with previous literature on the topic. Results indicate a lack of correlation between capacitance-voltage hysteresis and accumulation capacitance dispersion with frequency, suggesting that defects with remarkably different kinetics are involved in each phenomenon. This is assessed through the dependence of the capacitance-voltage hysteresis with DC bias and stress time, observing that permanent interface defect depassivation under bias has no effect on the hysteresis width after stress. Overall, capacitance-voltage hysteresis probes slow trapping mechanisms throughout the oxide and the bandgap, which are consistent with the negative charge trapping characteristic of the current-time curves for FGA samples at constant voltage stress. Instead, accumulation capacitance frequency dispersion probes defects with short trapping/detrapping characteristic times that can be linked to the stress induced leakage current of air exposed samples under constant DC stress. Experimental results indicate that each effect must be assessed separately due to the large difference in the kinetics of the probed defects.
关键词： metal-oxide-semiconductor stacks,forming gas annealing,defects,metal gate/high-k/n-InGaAs,trapping mechanisms,capacitance-voltage hysteresis,accumulation capacitance frequency dispersion
更新于2025-09-04 15:30:14