This invention relates to the thermal management, extraction of light, and cost effectiveness of Light Emitting Diode, or LED, electrical circuits. An integrated circuit LED submount is described, for the packaging of high power LEDs. The LED submount provides high thermal conductivity while preserving electrical insulation. In particular, a process is described for anodizing a high thermal conductivity aluminum alloy sheet to form a porous aluminum oxide layer and a non-porous aluminum oxide layer. This anodized aluminum alloy sheet acts as a superior electrical insulator, and also provides surface morphology and mechanical properties that are useful for the fabrication of high-density and high-power multilevel electrical circuits.