9 January 2018
Picture: Disco’s DAL7440 KABRA laser saw.
Tokyo-based equipment maker DISCO Corp has developed DAL7440, a laser saw that supports KABRA processing of 8-inch silicon carbide (SiC) wafers.
In the KABRA (Key Amorphous-Black Repetitive Absorption) slicing process, by continuously irradiating the laser vertically from the upper surface of the ingot, a separating layer that absorbs light is formed into a flat shape at the desired depth, enabling peeling and formation of wafers from this point.
At SEMICON Japan 2016 DISCO exhibited the DAL7420 laser saw (measuring 600mm x 1045mm x 1778mm), which supports KABRA processing of 6-inch wafers. However, R&D to enlarge wafer diameter has been progressing, involving for example the shipping of 8-inch sample wafers.
In response to this, as well as strong demand from wafer manufacturers, the DAL7440 laser saw (which measures 750mm x 1350mm x 1800mm) has been developed, to support KABRA processing of 8-inch wafers.
Maximum ingot thickness is 40mm (with a function for measuring ingot thickness). The system is alignment-free, thanks to an orientation flat detection function using auto alignment. A wafer printing function tracks the total number of processed wafers. In addition to 8-inch diameter ingots, the DAL7440 also supports future increases in ingot diameter.
In March, the DAL7440 will be set up in DISCO’s North Carolina office (Disco Hi-Tec America Inc) to more flexibly handle requests for processing tests in the USA.