Seen as the future of wide band gap semiconductor materials, single-crystal diamonds need to be fabricated in at least inch-size wafers if they are to be of use in industry. The key methods required to achieve this are 1) improving the growth of single crystals with sufficient quality over large areas at an acceptable growth rate, 2) enlarging the seed crystal, and 3) improving the fabrication of the freestanding wafers. This paper briefly reviews recent progresses and reports the most recent results of our research of solving these technical problems.
► By using a lift-off process with ion implantation, we fabricated clone substrates. ► These clones are found to be useful to fabricate 1 inch mosaic wafers. ► The lift off process is applied also to make several clones of this 1 inch wafers. ► Some characterizations imply their quality is close to those of HPHT substrates.
- Freestanding wafer;
- Mosaic wafer