Developments in the aluminium induced texturing (AIT) glass process

Light trapping is essential for Si thin-film solar cells on glass, and is generally realized by texturing the glass substrate. Aluminium induced textured (AIT) glass is one such method. To reproduce this texture by a cheap and fast way such as nano-imprinting, the best light trapping structure is required for the master template. Therefore, AIT glass needs to be optimised by varying the processing parameters: as-deposited Al thickness, Al deposition rate, and chemical etch composition. The conventional AIT etch, etching for similar to 20 s in mixture of 49%HF+69%HNO3, requires considerable experience to control the etch rate and therefore the final AIT structure, making it difficult to scale up for commercialization. In this work, this etch is replaced by an alternative etch comprising NaOH and a HF dip (4.9% HF solution). Textures prepared by the new etch demonstrate matched absorption and EQE as those prepared by the conventional etch.