Development of Ultraviolet (365nm) 100mW LED
We have recently succeeded in developing high-output ultraviolet LED of 365 nm wavelength. LED (light-emitting diode) is a product that enables the semiconductor chip itself to emit light by allowing current to flow in the chip, but conventional ultraviolet LED has a problem in that efficiency is rapidly degraded at wavelength shorter than 380 nm by self-absorption of gallium nitride layer that plays a role of buffer agent.
Therefore, we remove the gallium nitride layer or do not form the layer from the beginning and succeeded in developing ultraviolet LED that can provide high outputs even at short wavelength. Specifically, adopting 365 nm wavelength, ultraviolet LED that outputs 100 mW and 4.6 V when rated direct current is 500 mA has been successfully produced on a commercial basis for the first time in the world. For packages, airtight sealed type construction is employed, in which no organic materials such as resin, etc. is used at all as is the case of ultraviolet LED (380 nm) which were conventionally sample-shipped, and 1-mm2 LED chip is mounted.
As described above, we sample-shipped 380-nm wavelength ultraviolet power LEDs, but since customers strongly desire to have still shorter wavelength products and furthermore, the 365 nm wavelength is the wavelength of i beam of high-pressure mercury light whose increased applications are anticipated, we are extremely happy to have successfully developed product of this wavelength. For applications of this product, industrial apparatus, analyzers, medical equipment, etc. and in particular, deployment to photocatalyst application are expected. We will continue our research and development with our goal set to sample-shipment of the product next spring.