A5013772592- Spectroscopy and Laser Applications
- Semiconductor materials and devices
- Silicon Carbide Semiconductor Technologies
- Laser Design and Applications
- Atmospheric Ozone and Climate
- Electromagnetic Compatibility and Noise Suppression
- Advancements in Semiconductor Devices and Circuit Design
- Semiconductor Lasers and Optical Devices
- Diamond and Carbon-based Materials Research
- Integrated Circuits and Semiconductor Failure Analysis
- Semiconductor Quantum Structures and Devices
- Isotope Analysis in Ecology
- Advanced Surface Polishing Techniques
- Semiconductor materials and interfaces
- Particle accelerators and beam dynamics
- Electrostatic Discharge in Electronics
- Photonic and Optical Devices
- Copper Interconnects and Reliability
- Magnetic confinement fusion research
- Particle Accelerators and Free-Electron Lasers
ETH Zurich
2016-2021
Northwestern University
2012-2013
Quantum Devices (United States)
2012
We demonstrate quantum cascade lasers emitting at wavelengths of 3–3.2 μm in the InP-based material system. The laser core consists GaInAs/AlInAs using strain balancing technique. In room temperature pulsed mode operation, threshold current densities 1.66 kA/cm2 and 1.97 kA/cm2, characteristic temperatures (T0) 108 K 102 K, are obtained for devices 3.2 3 μm, respectively. Room continuous wave operation is achieved both wavelengths.
A dual-section, single-mode quantum cascade laser is demonstrated in continuous wave at room temperature with up to 114 nm (50 cm−1) of tuning near a wavelength 4.8 μm. Power above 100 mW demonstrated, mean side mode suppression ratio 24 dB. By changing the grating period, 270 (120 gap-free electrical for single gain medium has been realized.
The phenomenon of reduced energy capability power metal-oxide-semiconductor field-effect transistors (MOSFETs) at high avalanche currents is investigated in commercial 1.2-kV 4H-SiC MOSFETs. Unclamped inductive switching (UIS) measurements as well electrical transport simulations are used to identify the current paths and maximum currents, providing insight into design limits. devices show a for above 52 A due latching parasitic bipolar junction transistor (BJT). BJT also limits switchable...
In this work, the performance of thin silicon carbide membranes as material for radiation hard X-ray beam position monitors (XBPMs) is investigated. Thermal and electrical behavior XBPMs made from single-crystal diamond compared using finite-element simulations. Fabricated devices are also with a 12 µm commercial polycrystalline XBPM at Swiss Light Source Paul Scherrer Institute. Results show that can reach equivalent transparencies while showing improved linearity, dynamics signal-to-noise...
Silicon carbide (4H-SiC) devices experiencing avalanche conditions can reach temperatures above 1500 K. Simulation of impact ionization in should, therefore, include models valid up to such high temperatures. However, calibrations coefficients are available only 580 K, and simulations switching show deviations from measurements at higher In this paper, a more accurate model based on the underlying physics temperature anisotropic generation is proposed. This enables performed room along ${c}$...
In this article we present our latest work on the optimization of mid-infrared quantum cascade laser fabrication techniques. Our efforts are focused low dissipation devices, broad-area high-power photonic crystal lasers, as well multi-wavelength devices realized either arrays or multi-section distributed feedback (DFB) devices. We summarize achievements and update them with most recent results.
This paper presents an insight into the short circuit (SC) capability of Rohm’s discrete 1.2 kV, 80 mΩ state-of-the-art silicon carbide (SiC) double trench metal-oxide-semiconductor field effect transistor (MOSFET). SC measurements are performed to compare behavior Wolfspeed’s similarly rated planar MOSFET with Rohm devices. Short withstand time (SCWT) both designs under nominal operating conditions at room temperature is measured by performing destructive tests.
This paper describes our development efforts at Northwestern University regarding dual-section sampled grating distributed feedback (SGDFB) QCLs. These devices are the same size, but have much wider electrical tuning, than a traditional DFB laser. In this paper, I will show how we dramatically extended monolithic tuning range of high power quantum cascade lasers with side mode suppression. includes individual laser element up to 50 cm<sup>-1</sup> and 24 dB average capable room temperature...
When power MOSFETs experience a voltage spike initiating avalanche generation, large amount of is dissipated at the device junction. This leads to self-heating and lowers threshold voltage. Some sources indicate that unintended opening channel creates positive feedback, thereby increasing heat generation leading thermal runaway. Therefore, keeping off by applying negative gate bias should improve ruggedness. In this report, claim investigated comparing single pulse ruggedness commercial 1.2...
This work analyzes transport through metal organic chemical vapour deposition grown Iron doped Indium Phosphide (InP:Fe) for use as a current blocking layer in buried heterostructure Quantum Cascade Lasers. The nature of incorporation InP and electrical properties InP:Fe is investigated via simulation compared with measurement. Through simulations, we are able to predict the threshold onset rise test structures due avalanche injection carriers. In addition, benefit InAlAs barriers inserted...
Quantum Cascade Lasers (QCLs), operating in continuous wave (cw) at room temperature (rt) 3-3.5μm spectral range, which overlaps the fingerprint region of many hydrocarbons, is essential spectroscopic trace gas detection, environment monitoring, and pollution control. A 3μm QCL, cw rt demonstrated. This initial result makes it possible, for most popular material system (AlInAs/GaInAs on InP) used QCLs mid-infrared long-infrared, to cover entire range atmospheric window (3-5μm)....