Technology Outline (Process Description)

DS process has been pivotal production technology for the growth of mc-Si ingots. We have used India-made DS furnace to grow the mc-Si ingots, through mutual collaboration, interaction and sharing of technical inputs with HHV, Bangalore. DS furnace (capable to grow 800 Kg ingots), brick making and multi wafer slicing machines are fabricated indigenously, which are first of their kind in India. Optimization of various components and process parameters of the DS system backed by local and global modelling and simulation has led to the growth of high-grade mc-Si ingots. Slicing silicon ingot to produce wafer is achieved by using India’s first indigenous fixed abrasive diamond wire saws designed and developed by us. Control over the slicing of the silicon wafer was achieved by precise feed control of the diamond-impregnated wires, force along the wire, feeding of the ingot over the wire, thermal and kerf management. The optimization of various process parameters led to the successful production of mc-Si wafers of industrial size 182mm × 182mm (M10). Optimization of DS furnace process parameters to produce mono-like silicon ingots is being carried out.