Direct wafering technology

The wafer cost comprises around 40% of the total photovoltaic module costs [1]. Conventionally, the silicon wafer is made by growing an ingot and slicing them into desired thickness and the size. Recently, new wafer technologies have been developed to improve the quality of the wafers and to reduce cost. One such wafer technology is called ‘direct wafer manufacturing’ and is developed by 1366 Technologies [2]. This technology involves creating wafers individually in the desired shape and thickness with minimum waste. Unlike conventional methods to produce wafers, direct wafer technology involves a direct production of wafers which are cast directly from a silicon melt, by solidifying a silicon wafer shape directly from the surface of the melt onto a substrate. The wafer is then transferred to cool and, using a laser, the wafer is cut to the desired size. The silicon off-cuts from the wafer are collected and reused. The advantage of this process is that wafers are produced with less waste and with fewer fabrication steps which saves on cost and time. However, the material tends to have a high density of grain boundaries and impurities (without gettering), which tend to limit the overall material lifetime.

[1]        SEMI, “International Technology Roadmap for Photovoltaics (ITRPV) 8th Edition,” 2017, Available: hhttp://www.itrpv.net/Reports/Downloads/.

[2]        (2017, 2 August 2017). 1366 Technologies. Available: http://1366tech.com/