By Nick Gilbert
BT Imaging, a provider of luminescence-based inspection and quality control systems for use in the photovoltaic production industry, has unveiled a suite of production tools that allows photovoltaic wafer manufacturers to communicate and work efficiently with cell manufacturers to achieve the optimal cell efficiency.
Moreover, the new portfolio of tools allows cast mono wafer manufacturers to precisely lower cell efficiency spread and detect yield detractors. The new tools include the iS-G1 to perform inline cast mono grain inspection; the advanced iLS-W2 to perform on-the-fly photoluminescence (PL) inspection to test the quality of electrical wafer; a completely integrated inspection tool called the QS-W2 that allows automatic sorting of wafers; and the iQ, an automation unit that can accommodate the iS-G1 and/or the iLS-W2 to upgrade the existing manufacturing lines.
Using this set of tools, fully integrated photovoltaic producers and wafer manufacturers can now examine each wafer during production to know its electrical performance prior to its conversion into a photovoltaic cell so that they can command premium pricing for cells and wafers. The iLS-W2 performs on-the-fly inspection at rate of 3,600 wafers per hour and can be easily integrated into any type of wafer inspection system due to its modular compact design. It can grade cast mono and as-cut multi-crystalline wafers and will feature the capability to grade CZ mono silicon photovoltaic wafers very soon.
BT Imaging's new tools allow producers to grade cast mono wafers efficiently. Mono area fraction is the basis for the iS-G1 to grade wafers. Dislocation count is the basis for the iLS-W2 to grade mono-like wafers. The combination of the iLS-W2 and the iS-G1 offers a comprehensive solution for grading cast mono wafers. The new iQ automation unit can be integrated into a manufacturer’s existing wafer line to allow grading with the iLS-W2 and the iS-G1. The new QS-W2 stand-alone sorter allows automatic loading and sorting of wafers with the iLS-W2 and the iS-G1.