ABSTRACT High‐density and uniform diamond nucleation is the key to achieving high‐quality heteroepitaxial diamond films. Herein, a femtosecond (fs) laser‐induced diamond nucleation method is proposed for heterogeneous growth of high‐quality diamond films on silicon substrates. Specifically, a uniform and regular microstructure is first induced on the silicon substrate surface by fs laser, and then a high‐density and uniform diamond nucleation is achieved on the silicon surface thanks to the anchoring effect of the microstructure, so that the heterogeneous growth of high‐quality diamond film on the silicon substrate is realized by microwave plasma chemical vapor deposition process. The experimental results show that fs laser‐induced diamond nucleation has higher nucleation density and more uniform nucleation distribution than conventional mechanical grinding diamond nucleation, thereby obtaining diamond films with better quality, thicker thickness, and lower surface roughness. Furthermore, the obtained silicon/diamond substrate is used as a heat sink for the heat dissipation of an LED. Compared with the LEDs with a Si substrate and without a heat dissipation substrate, the working temperature of the LED at 220 s is reduced by 18.4°C and 6.6°C, respectively, demonstrating the potential of heteroepitaxial diamond film on a silicon substrate in the field of chip thermal management.
Wang et al. (Wed,) studied this question.