The patent discloses a method for modifying silicon (Si) surfaces to reduce reflections and enhance absorption across a broadband wavelength range (200 nm to 3300 nm). The method involves an eight-step process to fabricate three-dimensional grid structures of titanium (Ti) compounds on n-type Si substrates. These surfaces are CMOS compatible, biocompatible, and hydrophobic, providing broadband anti-reflective and self-cleaning properties.
Figure (1) Band diagram for as-deposited Ti on Si Two possibilities of Ti-compounds on Si (2) Descriptive fabrication steps (3) (a) Cross Sectional-SEM images taken at an angle of 5° tilt and (b) AFM Surface topography images [left] and the corresponding line scan[right] for S1,S2,S3 and S4 samples.
Silicon surfaces typically exhibit high reflectance and limited absorption beyond 1500 nm, limiting their use in various optical applications. Existing methods to enhance absorption either focus on narrow wavelength ranges, are costly, or involve complex and time-consuming fabrication processes.
- Fabrication of patterned Ti compounds on Si substrates.
- Eight-step process including RCA cleaning, deposition, lithography, and annealing.
- Formation of three-dimensional grid structures optimized for broadband absorption.
- CMOS compatibility and biocompatibility.
- Hydrophobic surface providing self-cleaning properties.
The prototype involves Si samples modified through an eight-step fabrication process to create patterned Ti compounds. These prototypes are tested for reflectance, absorbance, and hydrophobicity, ensuring they meet the desired optical and surface properties.
Early Prototype development and validation in relevant environment complete.
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The technology can significantly improve the efficiency of solar cells, enhance imaging and sensing devices, and provide better biocompatible surfaces for medical applications, thereby contributing to advancements in renewable energy, healthcare, and scientific research.
Photovoltaics, Healthcare industry and any industry requiring surfaces with low reflectance and high absorption across a broad spectral range.
202021015397
508123