Heat Transfer Analysis of a Diamond Chip Resistor in Planar Multijunction Thermal Converters

This paper presents the heat transfer analysis of a diamond chip resistor in a planar multijunction thermal converter (MJTC). Diamond, with the highest thermal conductivity among all the natural materials, is of much interest as a chip material to increase the thermal efficiency of the MJTC. The temperature distribution along the diamond chip resistor and thermal response time of the MJTC are calculated for three different chip materials: aluminum (Al2O3), aluminum nitride (AlN) and diamond. The thermal analysis shows that the temperature distribution along the chip is significantly reduced due to the high thermal conductivity of the diamond, suggesting increased input voltage range. The calculated output voltage of the MJTC with the diamond chip resistor increases by 2 times and 1.2 times, compared with those of conventional Al
2
O
3
and AlN chips. The thermal response time are 3.0 s, 0.9 s, and 0.6 s for Al2O3, AlN, and diamond, respectively.