Vol. 56, Issue 2, pp. 283-293 (2026)

Abstract

Silicon exhibited excellent optical properties in the visible to near-infrared band and had significant applications in optical communication, spectral detection, solar cells, and near-infrared sensors. However, optical devices made of silicon have a serious problem. Silicon has a very high reflectivity in the vision-infrared range, which will seriously reduce the efficiency and sensitivity of light usage. Therefore, in this work, femtosecond laser processing technology was employed to enhance its optical properties and increase its anti-reflection performance. This method fabricated large-area deep microholes, ordered and random, with low damage and low cost silicon microhole arrays. Experimental tests have shown that it has ultra-wideband anti-reflection performance (with a minimum reflectivity of 3.1% from 380 to 1100 nm).This experimental method could control the depth of silicon micropores by regulating the energy of femtosecond laser and the number of direct writes, thereby regulating its optical properties. This silicon deep microholes demonstrated self-cleaning and strong hydrophobic properties (water contact angle 130 ± 2°) in the hydrophilicity and hydrophobicity test. The microholes structure of Si exhibited excellent anti-reflection, self-cleaning, and strong hydrophobicity over a wide wavelength range, which was crucial for enhancing the performance of various optical, optical functional, and optoelectronic devices. It had also played a supporting and promoting role in the research and development of photovoltaic devices, COMS devices and spectral detection devices.