Diamond film thickness plays a decisive role in thermal dissipation performance, primarily by dictating the transition of the heat conduction mechanism and directly lowering the operating surface temperature of heat-generating devices:

1.Transition from "Point Dissipation" to "Area-Plane Dissipation"

The heat dissipation of diamond thin films is characterized by lateral diffusion, known as area-plane heat dissipation.

When the film is thin, it cannot dissipate heat effectively in a plane-like manner, exhibiting only the point heat dissipation mechanism of conventional materials. Thus, the ultra-high thermal conductivity of diamond is not fully utilized.

As the film thickness increases, the area-plane heat dissipation mechanism becomes increasingly pronounced and eventually stabilizes, leading to a dramatic improvement in overall thermal performance.

2.Significantly Reducing Device Operating Temperatures

In experimental tests where LED heating units were packaged on the diamond films and operated under identical electrical power, a greater film thickness led to a significantly lower LED surface temperature after 5 minutes of operation.

With other deposition parameters held constant, thicker films allow heat to be spread and dissipated rapidly through the area-plane mechanism, minimizing temperature rise.

3.Practical Implications for Manufacturing Efficiency

Because a minimum thickness is required to establish stable and efficient area-plane dissipation, obtaining a sufficiently thick film is a prerequisite for fabricating qualified heat spreaders.

Optimizing process parameters (like increasing microwave power or raising substrate temperature) to enhance the growth rate is aimed at reaching the required thickness for area-plane dissipation in a shorter time, thereby boosting production efficiency.