摘要 |
<p>A silicon nitride layer 12b is thermally grown on the topmost surface of the heat treatment jig 12 composed of silicon or silicon carbide in a nitrogen ambience. The silicon nitride layer 12b is thermally grown in a nitrogen ambience in the temperature range of 1,100 DEG C-1,300 DEG C. It is desirable to remove slightly the surface of the jig by, for example, hydrogen etching before thermally growing the silicon nitride layer 12b. After the etching, a silicon oxide layer can be thermally grown on the jig surface in an oxygen ambience before thermally growing the silicon nitride layer 12b. <IMAGE></p> |