Diamond is the ultimate material which has the best physical properties of all materials in terms of hardness, acoustic velocity, thermal conductivity, Young’s modulus, etc. Additional properties include transmittance of a broad wavelength spectrum from ultraviolet to infrared, thermal and chemical stability, and controllable electrical resistance/conductivity. These properties make diamond useable in a variety of applications, such as heat sinks, machining tools, optical components, audio components, and semiconductors.
Diamond Production Method
The present diamond synthesis method is high-pressure, high-temperature (HPHT) method. The homoepitaxial diamond growth process on HPHT-diamond substrate by Chemical Vapor Deposition (CVD) is also well known method for producing diamond substrate. This method is superior in the quality but limits the substrate size.
World's first, large diameter diamond production method
Namiki employs Heteroepitaxy targeting large diamond substrates.
In principal, hetroepitaxy, which uses a foreign material as a basal substrate, has theoretical possibility of producing diamond substrates with the same size as basal foreign substrates.
However, due to the heteroepitaxial strain owing to the lattice and thermal expansion differences of diamond and basal substrate, quality degradation and crack generation still occur in thick bulk diamond growth.
We made a new approach to overcome the obstacles in heteroepitaxy. Based on Ir/MgO basal substrate process technology which was developed by Aoyama Gakuin University, we combined with our own newly developed microneedle growth technology (JP Patent 6142415B) which enable to prevent crack generation and allow to grow stress-free, high quality, large diameter diamond substrate for stable production.
Ultimate diamond polishing - Plasma fusion CMP
For final processing of crystal substrate used in semiconductor field, we have developed Plasma Fusion CMP which has been developed through Kyushu University (Professor Toshiro Doi) collaborative research work. Consequently, an atomically flat diamond substrate becomes available to supply.