When small solid state opto-electrical devices, such as light-emitting diodes (LEDs) or laser diodes (LDs), are applied in a large or small backlight module or illumination module, many opto-electrical devices are needed to generate sufficient brightness or illumination for the modules. However, when the opto-electrical devices are operated at high power, the temperature of the module composed of the opto-electrical devices increases, thereby degrading the operational quality of the module and ultimately burning out the opto-electrical devices.
To resolve this high temperature issue, the module composed of the opto-electrical devices is typically cooled by fans set in the module or by increasing the heat dissipation area. However, regarding setting fans in the module, the vibration caused by the operation of the fans results in the lights flickering, and the fans consume additional power. Regarding increasing the heat dissipation area, although the heat sinks can be composed of metal with high thermal conductivity, glue mixed with metal is used to connect the opto-electrical device and the heat sinks, and the thermal conductivity of the glue is much lower than that of the pure metal. As a result, the heat generated during the operation of the opto-electrical device mostly accumulates at the connection interface, so that the heat sinks cannot transfer heat well, thereby making the heat sinks less effective, and easily damaging the opto-electrical devices during long-term operation or ultimately making the opto-electrical devices being operated with larger input power usage.
In addition, the heat sinks are typically connected to a circuit board with glue for electrically connecting the opto-electrical device and an outer circuit. Accordingly, the heat generated during the operation of the device accumulates at the glue, and the thermal conductivity of the circuit board composed of the plastic material is low, so the heat conductivity rate is low and greatly decreases the heat dissipation efficiency of the heat sinks.
Therefore, with the increasing demand for opto-electrical devices, such as light-emitting diodes and laser diodes, for backlight modules and illumination modules, a technique for manufacturing an opto-electrical device with high heat-sinking efficiency is required.