Investigations on the correlation between surface texturing histogram and the spectral reflectance of (100) Crystalline Silicon Substrate textured using anisotropic etching

- Anisotropic etching of silicon substrate with least reflectance has been optimized.
- Correlation between texture histogram and reflectance is presented.
- Ever reported lowest weighted reflectance of 10.76% for 300 nm-1100 nm is achieved.
- Pyramidal structures with an aspect ratio 0.44 resulted in the lowest reflectance.

Anisotropic etching of p-type Single crystalline (100) silicon substrate was optimized using KOH and IPA etchant combinations at constant temperature. Surface texturing histogram of the etched silicon substrates at different combinations were characterized using Zeta analysis, Scanning Electron Microscope and UV-vis spectral reflectance measurements. An increase in etchant ratio results in an increase in aspect ratio (height/base) and a decrease in the density of pyramid. Optimization of etchant ratio to 3:1 resulted in the presence of correlated pyramid distribution with an average aspect ratio of 0.44 and resulted in a lowest weighted reflectance of 10.76% for the spectral range from 300 nm to 1100 nm without anti-reflection coating.

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