Apparatus for manufacturing thin wafers of hard, non-metallic material such as for use as semiconductor substrates

Claim 1

Apparatus for manufacturing thin wafers of hard, non-metallic material, such as monocrystalline or polycrystalline material for use as semiconductor substrates, from a bar of such material, said wafers having at least one precisely planar surface, said bar having an end face and a substantially central longitudinal axis, comprising: an internal hole saw including a saw head and a cutting blade mounted for rotation around a slicing axis of rotation, said saw blade having a substantially circular internal cutting edge; a cup-shaped grinding wheel having an annular grinding region, said grinding wheel being mounted in said saw head for rotation, and means for rotating said grind wheel around a grinding axis of rotation; means for rotating said bar around said substantially central longitudinal axis thereof; axial feed means for advancing at least one of said grinding wheel and said bar towards each other in an axial direction substantially parallel to one of said grinding axis and said bar axis with both said grinding wheel and bar rotating until said grinding region of said rotating grinding wheel engages and planes said end face of said bar during rotation thereof to a substantially precisely planar condition; and radial feed means for advancing said bar, after said end face thereof is planed, in a radial direction with respect to said cutting edge of said saw blade and into engagement with said cutting edge until a wafer including said planed end face is sliced from said bar.