Development of Chip-on-board Packaging Integrated with Microchannel for Efficient Power Chip Module Heat Dissipation

With the continuous increase in heat flux of high-power chip modules, the resulting rise in chip junction temperature poses a substantial threat to the longevity and reliability of power chips. Chip-on-board (COB) packaging not only streamlines the manufacturing process and reduces the cost of the support structure, but also offers the benefit of lower thermal resistance, thereby enhancing heat dissipation. However, its broader application is hindered by the limitations of conventional, low-efficiency cooling techniques. To address this challenge, this study proposes a compact chip-on-board packaging integrated with microchannel (COB-MC) to enhance thermal management efficiency. The design features an array of closely arranged copper micropipes directly bonded to the underside of an aluminum-based printed circuit board (Al-PCB), forming an integrated microchannel structure that offers both high reliability and integration density. The COB-MC structure was successfully implemented in high-power chip module packaging. Thermal simulations and experimental evaluations under microchannel liquid cooling revealed a significant reduction in operating temperature— from 97 °C to 33.4 °C—representing a 65.7% decrease. Furthermore, a consistent heat dissipation capacity of 353 W/cm² was achieved. Notably, the optical output of the chip module increased from 12.35 W to 26.48 W, marking a 53.3% enhancement. These findings demonstrate that the COB-MC packaging structure significantly improves thermal performance and offers a viable solution for efficient heat dissipation in metal substrate packaging, thereby facilitating the advancement of solid-state lighting technologies toward higher power densities.