Refine
Year of publication
Document Type
Way of publication
- Open Access (2)
Keywords
- RRAM (4)
- 2d materials (1)
- Atomic layer deposition (1)
- Atomic layer deposition (ALD) (1)
- Boron nitride (1)
- Chemical vapour deposition (1)
- Chlorophyta (1)
- HfO2 (1)
- In-Memory Computing (1)
- Tagebauseen (1)
- Verilog-A (1)
- X-ray photoelectron spectroscopy (1)
- carbon (1)
- compact modeling (1)
- crystalline (1)
- dielectric (1)
- ellipsometry (1)
- eutrophic lake (1)
- filamentary switching (1)
- in-situ (1)
- in-situ X-ray photoelectron spectroscopy (1)
- multilevel switching (1)
- operando (1)
- quadrupol mass spectrometry (QMS) (1)
- sensors (1)
- structure (1)
- structured substrates (1)
Institute
BTU
The resistive switching properties of HfO2 based 1T-1R memristive devices are electrically modified by adding ultra-thin layers of Al2O3
into the memristive device. Three different types of memristive stacks are fabricated in the 130 nm CMOS technology of IHP. The switching properties of the memristive devices are discussed with respect to forming voltages, low resistance state and high resistance state characteristics and their variabilities. The experimental I–V characteristics of set and reset operations are evaluated by using the quantum point contact model. The properties of the conduction filament in the on and off states of the memristive devices are discussed with respect to the model parameters obtained from the QPC fit.
X-ray Characterization of Ge Dots Epitaxially Grown on Nano-structured Si Islands on SOI Substrates
(2013)
Selective growth of fully relaxed GeSn nano-islands by nanoheteroepitaxy on patterned Si(001)
(2016)
Functional ultra-thin oxide films deposited by atomic layer deposition on structured substrates
(2021)
In the last decades, atomic layer deposition (ALD) has gained prominence in the materials and surface science communities owing to its high potential for integration as a scalable process in microelectronics. ALD's largest strengths are its well-controlled layer-by-layer deposition and growth conformity on 3D structures. Yet, the ALD technique is also well known to lead to amorphous and defective, non-stoichiometric thin films, resulting in modified materials properties that may even preferentially be used in certain applications. To study these issues, we have developed an in-situ ALD reactor attached to an X-ray photoelectron spectroscopy (XPS) system, capable of switching between both pump and flow-type operation. This novel tool allows to cover the entire range of compounds and recipes used in ALD, thus clarifying the role of such defects at different deposition stages, growth conditions and film/substrate interfaces. To exemplify these sorts of studies, we show the deposition of Al2O3 5-10 nm films on nanostructured Si, and their use as substrates for functional CeOx ALD deposits.
Regional climate projections have been performed for Europe with the climate version CLM (version 3.1) of the 'Lokal-Modell' (LM) of the German Meteorological Service. CLM has been forced with output of the ECHAM5/MPIOM global climate model of the Max Planck Institute for Meteorology, which contributed to the fourth climate assessment report (AR4) of the International Panel on Climate Change (IPCC). The results of the global model for the IPCC A1B and B1 scenarios as well as the reconstruction of the last four decades of the 20th century (20C3M) for the AR4 are dynamically scaled down to the CLM grid cell size of about 18×18 km2. Climatological parameters including all model variables and additional quantities characterising the climate are available from the World Data Centre for Climate database run by the German climate service group Model and Data. They can be accessed by the general public at no costs with the help of M and D. In particular, the 'Service Group Adaptation' (SGA) has been established at M and D to assist adaptation projects funded by the German Federal Ministry of Education and Research (BMBF) giving advice on the interpretation of the CLM model results.
This work presents a new ultra-high vacuum cluster tool to perform systematic studies of the early growth stages of atomic layer deposited (ALD) ultrathin films following a surface science approach. By combining operando (spectroscopic ellipsometry and quadrupole mass spectrometry) and in situ (X-ray photoelectron spectroscopy) characterization techniques, the cluster allows us to follow the evolution of substrate, film, and reaction intermediates as a function of the total number of ALD cycles, as well as perform a constant diagnosis and evaluation of the ALD process, detecting possible malfunctions that could affect the growth, reproducibility, and conclusions derived from data analysis. The homemade ALD reactor allows the use of multiple precursors and oxidants and its operation under pump and flow-type modes. To illustrate our experimental approach, we revisit the well-known thermal ALD growth of Al2O3 using trimethylaluminum and water. We deeply discuss the role of the metallic Ti thin film substrate at room temperature and 200 °C, highlighting the differences between the heterodeposition (<10 cycles) and the homodeposition (>10 cycles) growth regimes at both conditions. This surface science approach will benefit our understanding of the ALD process, paving the way toward more efficient and controllable manufacturing processes.