On the Determination of Electron Effective Mass in 2DEGs in Gallium Nitride HEMT Structures
Temperature dependence of the Shubnikov de Haas oscillation observed in the temperature range of 1.8–6 K due to doubly occupied subbands in the two-dimensional electron gas (2DEG) in AlGaN/GaN HEMT structures grown by MBE inhouse has been used to determine the effective mass m* using a novel method of nonlinear curve fitting method which is assigned to be more accurate which is reflected by the R-squared value of the fitting than discussed by previous workers using conventional approximation in linear-curve fitting model. Also the range in which the approximation of the conventional method is valid has been found out.
KeywordsGaN HEMT Effective mass and Shubnikov de Haas oscillation
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The corresponding author acknowledges the DST financial assistance received under the grant No.DST/INSPIRE Fellowship/2012/347. The Authors would like to thank Dr. Raghvendra Sahai Saxena, SSPL, Delhi for his useful contribution.
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