Beryllium Oxide (BeO) nanoparticles were prepared using the polyacrylamide gel route method. The formation of the nanocrystallites was confirmed by x-ray diffraction (XRD) and transmission electron microscopy (TEM). Samples calcined at 690 C for 4 hrs exhibited particle sizes between 12 and 21 nm. The size of the BeO particles was also verified with TEM and agreed with the XRD results. Structural parameters such as microstrain, internal stress, and dislocation density were calculated using the XRD results. There was decreasing behavior of micro-strain and dislocation density for increased calcining time. The observed texture coefficient (TC) values suggested that the growth of (100) and (101) oriented BeO nano crystallite took place rather than (002) oriented particles. The observed high intensity peaks suggested that the growth of the BeO nano crystallites occurred preferentially with a (101) orientation.

Miniaturization of electronic package leads to high heat density and heat accumulation in electronics device, resulting in short life time and premature failure of the device. Junction temperature and thermal resistance are the critical parameters that determine the thermal management and reliability in electronics cooling. Metal oxide field effect transistor (MOSFET) is an important semiconductor device for light emitting diode-integrated circuit (LED IC) driver application, and thermal management in MOSFET is a major challenge. In this study, investigations on thermal performance of MOSFET are performed for evaluating the junction temperature and thermal resistance. Suitable modifications in FR4 substrates are proposed by introducing thermal vias and copper layer coating to improve the thermal performance of MOSFET. Experiments are conducted using thermal transient tester (T3ster) at 2.0 A input current and ambient temperature varying from 25 • C to 75 • C. The thermal parameters are measured for three proposed designs: FR4 with circular thermal vias, FR4 with single strip of copper layer and embedded vias, and FR4 with I-shaped copper layer, and compared with that of plain FR4 substrate. From the experimental results, FR4 I−shaped shows promising results by 33.71% reduction in junction temperature and 54.19% reduction in thermal resistance. For elevated temperature, the relative increases in junction temperature and thermal resistance are lower for FR4 I−shaped than those for other substrates considered. The introduction of thermal vias and copper layer plays a significant role in thermal performance.

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Carbon doped Aluminium Nitride (C-AlN) thin film was synthesized on Al and Cu substrates using RF sputtering and used as heat sink for high power LED. The optical properties of LED such as correlated color temperature (CCT) and brightness (LUX) was recorded by spectrometer and tested for various driving currents. Increased lux level was observed for high driving currents and showed the performance C-AlN thin film as good thermal interface material at high driving currents.The observed CCT values were in between 6180-6900 K and increased for high driving currents. At the lower driving current, CCT value was high for C-AlN on Cu than on Al.overall, the observed optical properties of LED using C-AlN thin film as thermal interface material was suggested to explore the usage of C doped AlN thin film as effective thin film thermal interface material for thermal management in solid state lighting applications.

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