Hitachi confirmed to produce 3 inch GaN wire substrate

April 24, 2007, Hitachi Electric Corporation (Hitachi Cable) that have been successfully prepared on GaN substrate 3 inches in diameter.

Thanks to Hitachi amplification substrate size wire "gap formation (VAS: Void Assisted Separation stripping method)" the new technology, the growth of GaN films on the sapphire substrate, the GaN films were deposited on titanium nitride film, and then heated to GaN decomposition in the mixed gas, the contact surface of GaN film and metal the film gap is generated, and then growing thicker GaN films by HVPE method in this layer of titanium nitride film.

Here is to reduce the gap layer caused by different lattice constant stress effect and improve the crystal quality and reduce the defect density of GaN thick film and warping effect, and low mechanical strength gap layer allows direct stripping of self support and large size GaN wafer.

The new technology is still in the research stage, and can not be commercialized. For the 4 inch Hitachi wire substrate, said there was no any clear plan, to be in-depth understanding of customer needs, further development. (