The invention discloses a solar-grade
silicon wafer being
cut by
a diamond wire and a
cutting method thereof. A mono-
crystalline silicon square rod is
cut by
a diamond wire. The
cutting method comprises the following steps that: the mono-
crystalline silicon square rod which is formed by squaring,
grinding and
sharpening a mono-
crystalline silicon circular rod, the mono-crystalline
silicon square rod is fixed on a resin strip through an
adhesive bar, the resin strip is fixed on an
adhesive plate, then the
adhesive plate and the mono-crystalline
silicon square rod are collectively placed into a working cabin to be preheated,
cutting liquid is circulated in the working cabin to work, then the
diamond cutting is performed, the
cut mono-crystalline silicon
wafer is inversely arranged on a degumming device to degum, and the mono-crystalline silicon
wafer is washed by ultrasonic and then is centrifugally dehydrated. Due to the adoption of the cutting method, the
photoelectric conversion efficiency and the cutting efficiency of the mono-crystalline silicon wafer can be improved, a silicon wafer with the thickness of 140 to 200 micrometers can be produced, the qualification rate of the product can reach more than 98 percent; and silicon
powder is recyclable, so valuable silicon resource can be saved, and the environment-friendly production can be really realized during the production process.