Patent ID: 8940266
Filing Date: 2015-01-27
Classification: C01B,C30B

Abstract:
1. A method for producing a single-crystal diamond substrate having a large area, comprising the steps of: (1) implanting ions into a parent substrate of single-crystal diamond to form a graphitized, non-diamond layer near a surface of the parent substrate, and subsequently etching the non-diamond layer to separate therefrom a single-crystal diamond layer above the non-diamond layer; (2) repeatedly subjecting the parent substrate used in Step (1) to the operation of Step (1), to separate from the parent substrate one or more single-crystal diamond layers having a substantially identical thickness to that of the single-crystal diamond layer separated in Step (1), wherein all of the single-crystal diamond layer obtained in Step (1) and the single-crystal diamond layers obtained in Step (2) are child substrates, wherein the separated faces of all of the child substrates have an off-set angle, crystal plane direction, strain distribution and defect distribution identical to those of the parent substrate, wherein each of the separated faces has been formed in Step (1) when separating each of the child substrates from the parent substrate; (3) placing the plurality of the child substrates on a flat support such that side faces of adjacent child substrates are in contact with each other, directions of crystal faces of all of the child substrates are identical, and the separated faces of the child substrates are exposed as top faces; and (4) growing a single-crystal diamond by a vapor-phase synthesis method on the separated faces of the plurality of child substrates placed on the support in Step (3), thereby bonding the plurality of child substrates.