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Analysis of stochastic processes in electronic components
Vlčková, Irena ; Šebesta, Vladimír (referee) ; Zajaček, Jiří (advisor)
The Bachelor Thesis deals with the interference of electronic parts, using of non-destructive analysis for electronic interference in semi-conductive parts and measured samples. The thesis is divided into thematic areas: Interference types; Spectrum of random continuous signals, Spectrum calculation due to the method of periodogram and the method sub-banding coding and following FFT, Apparatus for interference measuring, Results of interference measuring. In the practical part 5 and 6, there are measuring results of chosen electronic parts, transport and interference characteristics and they are compared with theoretical presumptions.
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The Noise Spectroscopy of Radiation Detectors Based on the CdTe
Zajaček, Jiří ; Štourač, Ladislav (referee) ; Hájek, Karel (referee) ; Grmela, Lubomír (advisor)
The main object of this work is noise spectroscopy of CdTe radiation detectors (-rays and X–rays) and CdTe samples. The study of stochastic phenomenon and tracing redundant low-frequency noise in semiconductor materials require long-term measurements in time domain and evaluate suitable power spectral densities (PSD) with logarithmic divided frequency axes. We have used the means of time-frequency analysis derived from the discrete wavelet transform (DWT) and we have designed the effective algorithm for PSD estimation, which is comparable with an original analog method. CdTe single crystal with Au contacts we can imagine as a series connection of two Schottky diodes with a resistor between them. The bulk resistance at constant temperature and other constant parameters changes due to the carrier concentration changing only. The p-type CdTe sample shows metal behavior with every temperature changes. Semiconductor properties of the sample begin to dominate just after some period of time. This behavior is caused by the hole mobility changing. The voltage noise spectral density of 1/f noise depends on the quantity of free carriers in the sample. All the studied samples have very high value of low frequency noise, much higher than it should have been according to Hooge’s formula. The excess value of low frequency noise is caused by the low carrier concentration within the depleted region.
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The Noise Spectroscopy of Radiation Detectors Based on the CdTe
Zajaček, Jiří ; Štourač, Ladislav (referee) ; Hájek, Karel (referee) ; Grmela, Lubomír (advisor)
The main object of this work is noise spectroscopy of CdTe radiation detectors (-rays and X–rays) and CdTe samples. The study of stochastic phenomenon and tracing redundant low-frequency noise in semiconductor materials require long-term measurements in time domain and evaluate suitable power spectral densities (PSD) with logarithmic divided frequency axes. We have used the means of time-frequency analysis derived from the discrete wavelet transform (DWT) and we have designed the effective algorithm for PSD estimation, which is comparable with an original analog method. CdTe single crystal with Au contacts we can imagine as a series connection of two Schottky diodes with a resistor between them. The bulk resistance at constant temperature and other constant parameters changes due to the carrier concentration changing only. The p-type CdTe sample shows metal behavior with every temperature changes. Semiconductor properties of the sample begin to dominate just after some period of time. This behavior is caused by the hole mobility changing. The voltage noise spectral density of 1/f noise depends on the quantity of free carriers in the sample. All the studied samples have very high value of low frequency noise, much higher than it should have been according to Hooge’s formula. The excess value of low frequency noise is caused by the low carrier concentration within the depleted region.
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Analysis of stochastic processes in electronic components
Vlčková, Irena ; Šebesta, Vladimír (referee) ; Zajaček, Jiří (advisor)
The Bachelor Thesis deals with the interference of electronic parts, using of non-destructive analysis for electronic interference in semi-conductive parts and measured samples. The thesis is divided into thematic areas: Interference types; Spectrum of random continuous signals, Spectrum calculation due to the method of periodogram and the method sub-banding coding and following FFT, Apparatus for interference measuring, Results of interference measuring. In the practical part 5 and 6, there are measuring results of chosen electronic parts, transport and interference characteristics and they are compared with theoretical presumptions.
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