Noise sources in polymer thick-film resistors

Abstract

Purpose – The paper aims to get the knowledge about electrical properties, including noise, of modern polymer thick-film resistors (TFRs) in a wide range of temperature values, i.e. from 77 K up to room temperature. The sample resistors have been made of different combinations of resistive compositions, either ED7100 or MINICO (M2013, M2010), and conducting pastes (for contacts) Cu- or Au-based, deposited on FR-4 laminate. Design/methodology/approach – The paper opted for an experimental study using either current noise index measurement in room temperature for large batch of samples or noise spectra measurement in temperature range 77-300 K for selected samples. Obtained noise maps, i.e. plots of power spectral density of voltage fluctuations vs frequency and temperature, have been used for evaluation of noise describing parameters like material noise intensity C and figure of merit K, for TFRs made of different combinations of resistive/conductive materials. Comparison of the parameters gives the information about the quality of the technology and matching the conductive/resistive materials. Findings – Experiments confirmed that the main noise component is 1/f resistance noise. However, low-frequency noise spectroscopy revealed that also noise components of Lorentzian shape, associated with thermally activated noise sources exist. Their activation energies have been found to be of a few tenths of eV. Research limitations/implications – The noise intensity of polymer TFRs depends on technology process and/or contacts materials. The use of Au contacts leads to better noise properties of the resistors. The results of the studies might be helpful for further improvement of thick-film technology, especially for manufacturing low-noise, stable and reliable TFRs. Practical implications – The paper includes indications for the materials selection for thick-film technology to manufacture low-noise, reliable and stable TFRs. Originality/value – Experimental studies of electrical properties of polymer TFRs by means of noise spectra measurements in wide range of temperature is rare. They give fundamental knowledge about noise sources in the modern passive electronic components as well as practical indications of selection material for thick-film technology, to obtain high performance components and get technological advantage.

Low-Noise Programmable Voltage Source

“…For example, noise characterization is needed in order to understand the fundamental causes of the detection limit in spectroscopy [2,3], data link budgets in free-space optics, etc. In the case of biased devices (such as transistors [4,5], varistors [6], photodetectors [7][8][9][10][11][12][13] and other materials [14][15][16][17]), the noise introduced by the biasing devices is also very important because it can mask the noise generated by the devices being investigated or limit the performances of the designed instruments. Indeed, in order to perform reliable noise characterization, we need to resort to ultra-low-noise power supply units that introduce negligible noise levels compared to those generated by the device-under-test (DUT).…”

Metrology and Measurement Systems

“…Instrumentation for a low frequency noise measurements (LFNM) is a tool used to characterize a wide spectrum of devices [1]. It is applied in many technologies, e.g., semiconductors [2,3], microelectronic materials [4][5][6][7][8][9][10], electro-chemical devices [11], photodetectors [12][13][14][15][16][17][18], as well as other materials [19][20][21]. In this research, some special amplifiers (ultra-low noise amplifier -ULNA) are widely used.…”