Method of processing of nitride semiconductor wafer, nitride semiconductor wafer, method of producing nitride semiconductor device and nitride semiconductor device
AssigneeSumitomo Electric Industries, Ltd.
InventorsKeiji Ishibashi, Hidenori Mikami, Naoki Matsumoto
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Abstract
A nitride semiconductor wafer is planar-processed by grinding a bottom surface of the wafer, etching the bottom surface by, e.g., KOH for removing a bottom process-induced degradation layer, chamfering by a rubber whetstone bonded with 100 wt %-60 wt % #3000-#600 diamond granules and 0 wt %-40 wt % oxide granules, grinding and polishing a top surface of the wafer, etching the top surface for eliminating a top process-induced degradation layer and maintaining a 0.5 μm-10 μm thick edge process-induced degradation layer.
Claims6
1-12. (canceled)
A method of processing a nitride semiconductor wafer comprising the steps of:
- flat-processing a bottom surface of the nitride semiconductor wafer;
- eliminating a process-induced degradation layer on the bottom surface by etching;
- chamfering an edge of the wafer by a diamond-bonded whetstone;
- flat-processing a top surface of the wafer;
- eliminating a process-induced degradation layer on the top surface by vapor-phase etching;
- and
- maintaining a 0.5-10 μm thick edge process-induced degradation layer remaining on the edge.
A method of processing a nitride semiconductor wafer comprising the steps of:
- slicing a nitride semiconductor crystal ingot into nitride semiconductor wafers;
- eliminating a process-induced degradation layer on a bottom surface by etching;
- chamfering an edge of the wafer by a diamond-bonded whetstone;
- flat-processing a top surface of the wafer;
- eliminating a process-induced degradation layer on the top surface by vapor-phase etching;
- and
- maintaining a 0.5-10 μm thick edge process-induced degradation layer remaining on the edge.
A method of processing a nitride semiconductor wafer comprising the steps of:
- grinding a bottom surface of a gallium nitride wafer;
- inducing a process-induced degradation layer on the bottom surface;
- etching away the bottom process-induced degradation layer with any one of KOH, NaOH and H3PO4 solutions;
- chamfering an edge of the gallium nitride wafer by a rubber-bonding whetstone;
- inducing an edge process-induced degradation layer on the edge;
- grinding a top surface of the gallium nitride wafer;
- inducing a process-induced degradation layer on the top surface;
- rough-polishing the top surface with rough whetting granules;
- fine-polishing the top surface with fine whetting granules;
- eliminating a part of the edge process-induced degradation layer;
- and
- maintaining a 1-3 μm thick edge process-induced degradation layer on the edge.
Dependencies are inferred from the claim text.