Optimization of $\hbox{Mn}_{3}\hbox{Ag}_{1 - x} \hbox{Cu}_{x}\hbox{N}$ Antiperovskite Compound Fabrication for Resistance Standard

Abstract

We performed a detailed evaluation of the temperature coefficient of resistance of manganese nitride antiperovskite compounds, i.e., Mn <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> Ag <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1-</sub> <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i> Cu <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> N, around 23 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">°</sup> C. The second-order term of the temperature coefficient β was found to show a rough correlation with the Cu content. For a Cu content <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i> = 0.4, the compound Mn <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> Ag <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.6</sub> Cu <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.4</sub> N shows the lowest temperature coefficients. The drift rate of the samples was also investigated. The drift rate was suppressed to about 1/30 by higher temperature annealing, and the lowest drift rate was 9.1 (μΩ/Ω)/year. We expect that this antiperovskite compound will be useful for precision resistors and improve the temperature coefficient of resistors by process optimization so that they can be used to produce standard resistors for example.