| dc.description.abstract | With the continuous advancement of semiconductor technology, Silicon Carbide (SiC) has become a key material for high-performance electronic components due to its excellent physical properties. Against this background, this research aims to explore SiC materials. Laser modification technology is applied to SiC slicing, altering the internal structure of SiC through laser energy to form a modified layer. The thickness of the modified layer reflects the power and depth of laser action during laser slicing, thereby affecting wafer quality. Therefore, we employ Shape From Focus (SFF) technology to measure the thickness of the modified layer inside SiC, improving wafer quality and the stability of the modification process. Through systematic investigation and experimentation, we innovatively attempted and optimized the application of SFF technology on SiC materials, achieving significant progress, especially in measuring the thickness of the modified layer.
The research first summarizes the basic properties of SiC materials, their current applications in high-tech fields, and the importance of modified layer thickness. Next, we analyze the principles and application prospects of SFF technology. Through experimental exploration, this study successfully developed a SFF system for measuring the internal modified structure of SiC and compared and evaluated the effectiveness of different focus value algorithms in measuring the thickness of the SiC modified layer. The results show that in longitudinal measurements, the system′s longitudinal resolution is 0.8 µm. Using the Scharr algorithm combined with a normal distribution filter threshold, the measured thickness of the modified layer has an error of only 5 % compared to the results measured by a white light interferometer microscope. Furthermore, this study further verified the performance of the SFF system using a THORLABS optical resolution test target as a standard. In lateral measurements, we compared its standard length with the length calculated from images captured by the SFF system, showing an error of less than 1 % between the two. The lateral resolution of this system is 3.45 µm, with a diffraction limit of 1.8 µm, conforming to the theoretical diffraction limit. This result demonstrates the accuracy of the SFF system in both longitudinal and lateral measurements. Finally, this research also analyzes potential sources of error in the measurement process using the SFF system, explores various potential influencing factors, and proposes corresponding optimizations to enhance system performance. | en_US |