Abstract
A mold coating material for a melt‐shaped crystal growth technique has been developed. After studying the contact angle and reaction between the molten silicon and other various high melting point materials, it was found that for shaped crystal growth with a lower impurity contamination level, a combination coating of 
and 
is suitable for a mold coating material. A double layer coating was applied to the graphite mold base. The bottom layer in the mold, which had a 100–150 μm thickness, consisted of 
that had been formed by nitriding a spray‐coated Si powder. The 200 μm thick top layer consisted of a 
material. It had been produced by oxidizing a sprayed‐on coating consisting of 
powder mixed in a silanol liquid. Using the mold prepared with these coatings, a melt‐shaped crystal growth technique was carried out by the spinning‐casting process. Polycrystalline silicon sheets, with a 
rectangular dimension and 0.5 mm thickness the size of a mold cavity, were obtained without adhesion to the mold. The sheet had an oxygen content of 1.7 ppm and a carbon content of 0.33 ppm. The mold was usable repeatedly up to 10 times.