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1

Noise spectroscopy of resistive components at elevated temperature

Stadler A.W., Zawiślak Z., Dziedzic A., Nowak D.

Metrology and Measurement Systems

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2014

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Vol. 21, nr 1

15--26

EN

Studies of electrical properties, including noise properties, of thick-film resistors prepared from various resistive and conductive materials on LTCC substrates have been described. Experiments have been carried out in the temperature range from 300 K up to 650 K using two methods, i.e. measuring (i) spectra of voltage fluctuations observed on the studied samples and (ii) the current noise index by a standard meter, both at constant temperature and during a temperature sweep with a slow rate. The 1/f noise component caused by resistance fluctuations occurred to be dominant in the entire range of temperature. The dependence of the noise intensity on temperature revealed that a temperature change from 300 K to 650 K causes a rise in magnitude of the noise intensity approximately one order of magnitude. Using the experimental data, the parameters describing noise properties of the used materials have been calculated and compared to the properties of other previously studied thick-film materials.

2

Analysis of noise and non-linearity of I-V characteristics of positive temperature coefficient chip thermistors

Sita Z., Sedlakova V., Majzner J., Sedlak P., Sikula J., Grmela L.

Metrology and Measurement Systems

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2013

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Vol. 20, nr 4

635--644

EN

Noise spectroscopy and I-V characteristic non-linearity measurement were applied as diagnostic tools in order to characterize the volume and contact quality of positive temperature coefficient (PTC) chip sensors and to predict possible contact failure. Correctly made and stable contacts are crucial for proper sensing. I-V characteristics and time dependences of resistance were measured for studied sensors and, besides the samples with stable resistance value, spike type resistance fluctuation was observed for some samples. These spikes often disappear after about 24 hours of voltage application. Linear I-V characteristics were measured for the samples with stable resistance. The resistance fluctuation of burst noise type was observed for some samples showing the I-V characteristic dependent on the electric field orientation. We have found that the thermistors with high quality contacts had a linear I-V characteristic, the noise spectral density is of 1/f type and the third harmonic index is lower than 60 dB. The samples with poor quality contacts show non-linear I-V characteristics and excess noise is given by superposition of g-r and 1/fn type noises, and the third harmonic index is higher than 60 dB.

3

Ageing of cadmium telluride radiation detectors and its diagnostics with low frequency noise

Andreev A., Sik O., Grmela L., Sikula J.

Metrology and Measurement Systems

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2013

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Vol. 20, nr 3

385--394

EN

Samples of CdTe single crystals which are used as radiation detectors were periodically measured during a long time interval with different values of an applied voltage. The samples were also periodically exposed during long time periods to high temperatures of 390 K and to rapid changes of temperature from 300 K to 390 K. After 1.5 years of measurements we observed ageing of the samples which resulted in deterioration of their transport characteristics. The resistance of the samples increased significantly and current-voltage characteristics were unstable in time. Noise spectroscopy showed that low frequency noise can be used for detection of CdTe sample ageing as its spectral density increases significantly comparing to the 1/f noise of a high quality sample.

4

Zjawiska fluktuacyjne w obszarze interfejsu warstw rezystora grubowarstwowego

Stadler A. W., Kolek A., Zawiślak Z., Mleczko K.

Elektronika : konstrukcje, technologie, zastosowania

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2008

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Vol. 49, nr 11

22-25

PL

Pokazano, że pewne systemy past rezystywnych i przewodzących używane do wytwarzania rezystorów grubowarstwowych cechuje wzrost gęstości termicznie aktywowanych źródeł szumów ulokowanych w obszarze interfejsu warstw. Te źródła szumów podlegają procesowi przełączania, który skokowo zmienia układ aktywnych fluktuatorów i ich wkład w całkowity szum mierzony na zaciskach rezytora. Badania pozwalają związać zjawisko przełączania z uwalnianiem naprężeń mechanicznych, które w rezystorach grubowarstwowych powstają na skutek niedopasowania temperaturowych współczynników rozszerzalności liniowej materiałów wchodzących w skład warstw rezystywnej i przewodzącej oraz podłoża.

EN

It is shown that certain resistive and conductive inks used for the fabrication of thick film resistors are characterized by enhanced denisty of thermally activated noise sources localized in the resistive/conductive layers interface. These noise sources are subjected to the switching phenomenon, which narrowly changes the set of active fluctuators and their contribution to the overall noise measured at resistors terminations. Extensive experiments allow to attribute the switchings to the relaxation of mechanical stress, which in thick film resistors appears due to the mismatch of thermal expansion coefficients of the materials contained in the layers and/or the substrate.

5

Źródła szumów w rezystorach grubowarstwowych na bazie dwutlenku rutenu

Kolek A., Zawislak Z., Stadler A. W.

Elektronika : konstrukcje, technologie, zastosowania

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2005

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Vol. 46, nr 10

38-40

PL

Omówiono metodę pomiarów weryfikujących koncepcję, zgodnie z którą źródłem szumów niskoczęstotliwościowych są systemy dwustanowe o kinetyce aktywowanej termicznie. Pokazano, że takie systemy wywołują szumy w rezystorach grubowarstwowych wykonanych z past rezystywnych na bazie dwutlenku rutenu i szkła.

EN

A study on low-frequency noise sources in thick film resistors made of resistive pastes based on ruthenium dioxide and glass has been presented. The paper focuses on the excess noise spectrum dependence on temperature in the range 77 K < T < 300 K. Experimental data have been then analyzed to extract characteristic values of activation energy and time constant describing unique features of the measured spectra. It has been proved that the noise in RuO2 + glass thick film resistors is caused by two-states systems of thermally activated kinetics.