A5062584523- Semiconductor materials and devices
- GaN-based semiconductor devices and materials
- Ga2O3 and related materials
- Advancements in Semiconductor Devices and Circuit Design
- Advanced Memory and Neural Computing
- Semiconductor materials and interfaces
- Photocathodes and Microchannel Plates
- Mobile Health and mHealth Applications
- Advancements in Battery Materials
- Health and Medical Studies
- Electronic and Structural Properties of Oxides
- Photonic and Optical Devices
- Behavioral Health and Interventions
- ZnO doping and properties
- Advanced Battery Technologies Research
- Electrical and Thermal Properties of Materials
- Metal and Thin Film Mechanics
Ferdinand-Braun-Institut
2018-2019
Siemens (Austria)
2014-2018
Infineon Technologies (Austria)
2014-2018
University of Kassel
2015-2017
Infineon Technologies (Germany)
2015
The transient recovery characteristics of the threshold voltage drift (ΔV <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sub> ) GaN-based HEMTs with a SiO xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> gate dielectric induced by forward bias stress are systematically and comprehensively investigated for times from 100 ns to 10 ks, 4 μs biases 1 7 V. measured data analyzed using concept capture emission time maps. It is shown that...
The high density of defect states at the dielectric/III-N interface in GaN based metal-insulator-semiconductor structures causes tremendous threshold voltage drifts, ΔVth, under forward gate bias conditions. A comprehensive study on different dielectric materials, as well varying thickness tD and barrier tB, is performed using capacitance-voltage analysis. It revealed that trapped electrons, ΔNit, scales with capacitance spill-over conditions, i.e., accumulation a second electron channel...
The etch mechanism of group‐III‐nitrides in hot H 3 PO 4 has been studied and compared to KOH. etched surfaces were investigated by AFM, SEM, TEM, EDX the solutions NMR. AlGaN is shown be selectively low temperature or molten KF · 2H 2 O. material dependency causes much flatter pit angles for over GaN as well 27 Al‐NMR investigations prove a fast ligand exchange homogenous ligands. 31 P‐NMR confirms that dissolved metal present AlH 2+ no hydration takes place nor does water play role...
The degradation of AlGaN-based metal-semiconductor-metal photodetectors under UV illumination has been studied. Oxidation triggered by the presence moisture and mobile carriers at semiconductor surface was found to be mechanism. UVC devices with Al0.5Ga0.5N absorbers show stable performance for more than 1000 h intensities around 10 mW cm−2 low dark current when passivated after metallization SiNx. UVB Al0.25Ga0.75N absorber layers were sensitive here additional protection a thin SiN layer...
We report on AlGaN/GaN MIS-HEMTs with a thermally stable dielectric/AlGaN interface induced by plasma fluorination. The treatment leads to modification of the "native" surface donors and fundamentally different device defect behavior. feasibility III-N modifications shows new direction for reducing VTh drifts or possibility engineering defects.
The influence of surface modifications on the Schottky barrier height for gallium nitride semiconductor devices is frequently underestimated or neglected in investigations thereof. We show that a strong dependency heights nickel/aluminum–gallium (0001) contacts terminations exists: linear correlation increasing with electronegativity superficial adatoms observed. negatively charged compete present nitrogen over available (or aluminum) orbital to form an electrically improved termination....
Investigations of chemical species at the dielectric/III‐N interface remain an important question in order to understand origin surface states, which are present heterostructure surface. In this work, we demonstrate a sample preparation technique analyze existing by X‐ray photoelectron spectroscopy (XPS) through thin uniform silicon nitride (Si 3 N 4 ) layers 1.4 ± 0.2 nm. We show that it is crucial as possible but thick necessary avoid oxygen diffusion passivation. Due sufficient...
Gallium nitride based high electron mobility transistors are widely known for their operational instabilities regarding interface defects to the dielectric. In this paper, we discuss a III-N surface treatment that results in an electrically more defined and hence narrower distribution of present states compared original, untreated interface. This modification is caused by remote plasma fluorination surface. We show it very distinctive processing which cannot be reproduced other techniques or...
Threshold voltage instabilities are investigated in GaN-based metal-insulator-semiconductor (MIS) high-electron-mobility-transistors (HEMTs) with specially designed on-wafer heaters structures. The based on metal lines or 2-dimensional electron gas (2DEG) resistors and enable to choose the temperature during stress recovery stress-recovery experiments independently. It allows decouple thermal activation of capture (<; 0.9 eV) emission (0.4-0.9 processes at dielectric/nitride interface, which...
The development of efficient (In)AlGaN light emitting diodes (LEDs) in the ultraviolet B (UVB) spectral region (280nm-320nm) is essential due to their vast commercial potential. UVB LEDs are expected not only replace traditional mercury lamps applications such as curing materials and phototherapy but also establish new fields plant growth sensing. Although a lot progress has been made on performance LEDs, efficiency devices well lifetime still needs be improved. In this study influence...
Abstract Background Walking is an appropriate mode to increase or maintain the physical activity behavior. However, physically inactive adults often need support in order their level. The aim of presentation inform about nudging framework within app Time2Walk, recruitment study participants for both time points, and development walking behavior over time. Methods were recruited via social media, press releases, advertising material personal contacts. A pre-post single group design was...