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A comprehensive investigation on the low-field 2-DEG mobility in InxAl1-xN/AlN/GaN heterostructure has been made through Hall experimental and numerical calculation based on an ensemble Monte Carlo (MC) approach. Hall measurement on a lattice-matched (LM) In0.18Al0.82N/AlN/GaN heterostructure grown by metal-organic chemical vapor deposition (MOCVD) has been carried out as a function of temperature ranging from 77 to 405 K. A more rigorous model is presented taking both inter- and intra-subband scattering into account. The scattering rates are derived from the results of the electron density, the quantized energy levels, and the corresponding wave functions based on the self-consistent solutions of Poisson’s and Schrödinger’s equation given in our previous work. We confirm that the interface scattering process dominates the mobility within the low temperature (77–130 K), as increasing of the temperature, the highly inelastic scattering caused by partial occupation of the higher subband is responsible for the rapid degradation of the 2-DEG mobility. The role of surface morphology and indium fraction of the heterostructure on the dependence of the 2-DEG mobility have been clarified qualitatively in detail. The calculated results are widely compared with the published literature and our experimental finding. A reasonable agreement is achieved. [ABSTRACT FROM AUTHOR]

The course "Materials in Electrical Engineering" is a core course in the Mechatronics curriculum at the Faculty of Technical Sciences, University of Novi Sad, Serbia. In the past, this course was comprehensive and mainly theory-based. Teaching methods used in this course had not been changed for many years, and were mainly based on a traditional approach. They were therefore often outdated, and boring for students. In addition, the lack of modern materials characterization equipment was a significant weakness of the course in its early stages. This paper presents the main aspects of the modified course, which features a greater inclusion of modern equipment in its teaching methodology; in particular it produces the Hall effect measurement system as an indispensable characterization technique in education, research and in the semiconductor industry. This paper also describes how students can be taught to use the Hall effect measurement system to determine the structural and electrical characteristics of different materials. Finally, students' feedback and observations on the modified course and the applied teaching methodology are discussed. [ABSTRACT FROM AUTHOR]