PURPOSE:To reduce the defect of a wafer surface and control its deformation at the same time, and to obtain the manufacture of semiconductor wafers of large size which are suitable to increase the density, by providing the process of forming grooves by selectively etching the whole or part of the back region of the title wafer and the process of heat-treating said wafer. CONSTITUTION:Grooves 12 are concentrically formed in the back of an Si single crystal wafer 11 by using the photo resist technique or plasma etching. Here, the groove is made 1-10mum deep and 10-100mum wide. Next, on heat- treatment of the wafer 11 in inactive gas atmosphere such as nitrogen, the back of the wafer 11 is deformed in a recess form, and its front in a projection form; then, a strong crystal stress field generates in the neighborhood of the periphery 13 of the groove 12. However, this region serves as the trap center for crystal defects present at the surface region 14 of the wafer. Besides, recessing the wafer back and projecting its front with good controllability facilitate the transcription of IC patterns to the wafer surface by the photo resist technique necessary for wafer surface processing.
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