Boron-doped aluminum nitride (B-A1N) thin films were synthesized on A1 substrates by using chemical vapor deposition method by changing the synthesis parameters and were used as thermal interface material for high power light emitting diode (LED).The B-A1N thin film-coated A1 substrate was used as heat sink and studied the performance of high power LED at various driving currents.The recorded transient cooling curve was evaluated to study the rise in junction temperature (Tj),total thermal resistance (Rth-tot) and the substrate thermal resistance (Rth-sub) of the given LED.From the results,the B-A1N thin film (prepared at process 4) interfaced LED showed low Rth-tot and Tj value for all driving currents and observed high difference in Rth-tot (△Rth-tot =2.2 K/W) at 700 mA when compared with the Rth-tot of LED attached on bare A1 substrates (LED/Al).The Tj of LED was reduced considerably and observed 4.7 ℃ as △Tj for the film prepared using process 4 condition when compared with LED/A1 boundary condition at 700 mA.The optical performance of LED was also tested for all boundary conditions and showed improved lux values for the given LED at 700 mA where B-AlN thin film was synthesized using optimized flow of A1,B and N sources with minimized B and N content.The other optical parameters such as color correlated temperature and color rendering index were also measured and observed low difference for all boundary conditions.The observed results are suggested to use B-A1N thin film as efficient solid thin film thermal interface materials in high power LED.