Single crystal diamonds are a process of growing the diamond material layer by layer. They are grown from a gas through the microwave plasma chemical vapour deposition method. Single crystal diamond plates are valuable for quantum communication devices, quantum sensors, deep UV detectors, single-photon detectors and high-energy particle detectors. Lower purity grades of single crystal diamonds are also helpful in mechanical tool development. 

The growth of polycrystalline diamond plates takes place in the form of multi-orientation giving it the characteristic polycrystallinity. These are grown over a non-diamond substrate via chemical vapor deposition (CVD) process. As these diamond plates undergo polishing, they become optically translucent and even transparent. These properties of polycrystalline diamond plates makes them valuable for optical windows, heat spreaders, tool coatings and electrochemical electrodes.