Modelovanje i simulacija karakteristika MOS tranzistora naprezanih jakim električnim poljem
Committee membersPešić, Biljana
MetadataShow full item record
One of the most frequent causes of the unstable operation of the MOS components is, besides high temperature and radiation, the exposure of gate oxides and the component structure to powerful electric fields, which happens when the voltages, whose values are similar to the breakdown voltage, are conducted onto the gate contact. Therefore, this doctoral dissertation explores the effects produced by the voltage strain of the gate oxides of the commercial MOS and powerful VDMOS transistors. The research is based on the use of the programs for the simulation of the technological string for the production of electrical characteristics of the semiconducting components of ATHENA and ATLAS, which are the components of Silvaco TCAD (Technology Computer-Aided Design) software package. The main idea is to benefit from the characteristic of the electrical characteristics simulator of the semiconducting components ATLAS to separate and analyse separately various effects. Thus, it is possible to ob...serve that generated neutral and electrified donor and acceptor centres of operation (defects), generated in the oxide on the mid-surface Si/SiO2 and in a bulk of semiconductors, affect the electrical characteristics of MOS and VDMOS transistors, such as: threshold voltage, drain current, transmitting and output characteristics, etc. The study offers a description of the built-in system of basic semiconducting equations, built into the program ATLAS, and a review of the mobility model of the carriers and the generation process and carrier recombinations, as well as the values of their parameters that are most frequently used in the procedure of simulation of the electrical characteristics of semiconducting components. Moreover, a review of degradation models, built into the program ATLAS that enable the simulation of HEF strain of MOS transistors, is presented. The effects of fixed charges on mid-surface, donor and acceptor centres of operation generated on the mid-surface Si/SiO2 of donor and acceptor centres of operation generated in a bulk of semiconductors and the effect of the depassivation of the links Si≡H on mid-surface Si/SiO2, on electrical characteristics of n-channel MOS and n-channel VDMOS power transistors have been analysed separately. The results of this research, which indicate the direction of the change of electrical characteristics depending on the presence of generated centres of operation and charge in the component structure, as well as the results obtained by experimental characterisation of the commercial n-channel VDMOS transistor of IRF510 power, exposed to HEF strain by conducting the voltage =+80V onto the gate contact for =150 minuta, have been used to identify which defects and charges are generated during HEF strain and which effects have a dominant impact on the changes of electrical characteristics. Lastly, the HEF strain of the transistor IRF510 has been simulated, the results of which are analogous to a great extent to the experimentally determined characteristics.
Faculty:University of Niš, Faculty of Electronic Engineering
- Physical and functional effects of radiation interaction with electrotechnical and biological systems (RS-171007)