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Ferroelectric doped hafnium oxide might be able to revive the ferroelectric memory as a candidate for future non-volatile memories. Recent publications have reported ferroelectricity in HfO2 films deposited via physical vapor deposition (PVD) and thermal atomic layer deposition (ALD). Within this thesis, such layers have been fabricated by a plasma enhanced ALD process for the first time. Using an O2 remote plasma to oxidize TEMAHf and TMAl, respectively, Al:HfO2 stacks with different compositions have been deposited. Sputter deposited TiN was used as bottom and top electrode to form metal-insulator-metal capacitors. Compared to the PVD or thermal ALD films reported in literature, the plasma enhanced ALD films exhibited one to two orders higher leakage current at 1 V. The root of this higher leakage are oxygen vacancies as well as carbon and nitrogen impurities in the range of several at%. Despite the consequential perturbing effects, the main trends reported earlier are discernable. Just these perturbing effects turn out to substantiate the current explanation of a ferroelectric phase as route source for the observed electrical behavior.
The People's Republic of China has had the aim of a (socialist) market economy since 1976. Nevertheless, it is still under dictatorial control. In this paper it is analysed if the Chinese political system is compatible with a market economy and in which way the classification of a socialist market economy is justified. Finally, an explanation why the term sino-capitalism fits for the Chinese economic system best will be given.
As one of the key technologies involved in communication networks, all-optical switching has witnessed many research efforts during the last decade. This work presents a detailed investigation of the properties and attractive interaction of spatial solitons in nematic liquid crystals for all-optical switching devices. This includes a description of basic properties such as their multimode behavior, as well as their power dependent interactions and signal steering. Furthermore, the temporal performance of an all-optical switching setup is analyzed and discussed. Thanks to their long-range, phase and wavelength independent interactions at milliwatts powers, and despite their slow response time in switching applications, nematicons proved to be an extremely promising testbed for soliton-based devices, including signal waveguides and power-dependent spatial steering devices.
The objective of this document is to design a connection between the devices of the two technologies SunSpec and Smart Energy 2.0 without the establishment of security backdoors. Smart Energy 2.0 devices should be able to gather data from SunSpec devices and modify writable registers for controlling purposes. Among other alternatives, the gateway proves itself as the most realistic and reasonable option and is chosen for further investigations. The connectivity requirements for such a device are analysed and mentioned. Interoperability between both networks is the core function of the gateway and established by the development of a Smart Energy 2.0 function set that implements the ability to represent SunSpec devices as resources in the Smart Energy 2.0 network. The gateway utilizes existing and introduces new mechanisms that maintain the high standard of security in Smart Energy 2.0 without any drawbacks. The document shows fundamental architectural approach and generally explains the functional and security mechanisms, but does not describe a complete gateway implementation.
The aim of this work is the analysis of characteristic properties of fuel jets in internal combustion engines for steady and transient spray velocities by means of CFD. The simulations were done using DNS. The used software is Gerris. Calculations with different Reynolds numbers, Weber numbers and density ratios were done. The adaptations of an already existing simulation file included the implementation of necessary output capabilities. The analysis of obtained data was done by previously created macros. The obtained non-dimensional results give information on penetration, number of droplets, SMD and droplets size distribution. One calculation was compared to experimental data.