Thermal transient analysis of LED using carbon doped AlN film deposited on metal substrate as heat sink

Abstract

AlN and Carbon-doped AlN (C-AlN) thin films were grown on metal substrates (Cu and Al) and heat sink by RF coupled DC sputtering. The thermal transient measurement was recorded for the given Light Emitting Diode (LED) attached with AlN and C-AlN thin film coated metal substrates and heat sink at various driving currents. The rise in junction temperature (T\(_{J})\) of LED was low for C-AlN (74.11 \(^{\circ }\text {C}\)) thin film coated Cu substrate than AlN coated Cu (82.40 \(^{\circ }\text {C}\)) substrate measured at 550 mA. The total thermal resistance (R\(_{th{\text {-}}tot})\) value (38.94 K/W) for C-AlN deposited on Cu was lower than for C-AlN prepared on Al substrate (42.46 K/W). On the other hand, Cu substrate showed good heat transfer properties than Al substrate and heat sink in terms of T\(_{J}\) and R\(_{th{\text {-}}tot}\). The total R\(_{th}\) of LED was comparatively low for C-AlN boundary condition than for high surface area heat sink. Overall, the observed results suggested the possibility of usage of C-AlN thin film as thermal interface materials for LED applications.