Patent ID: 8258603
Filing Date: 2012-09-04
Classification: B01J,C09K,C30B,H01S

Abstract:
1. A solid-state far ultraviolet light emitting element consisting of a hexagonal boron nitride single crystal which is substantially free of oxygen impurities, excited by electron beam irradiation to emit far ultraviolet light having a maximum light emission peak in a far ultraviolet region at a wavelength of 235 nm or shorter, wherein said hexagonal boron nitride single crystal is obtained by high-temperature and high-pressure treatment from 20,000 to 60,000 atmosphere pressure at least 1500° C., and said high-temperature and high-pressure treatment uses alkali earth metal boron nitride which is substantially free of oxygen impurities or alkali metal and alkali earth metal boron nitrides which are substantially free of oxygen impurities as a solvent.