FULLY TRANSPARENT ULTRAVIOLET OR FAR-ULTRAVIOLET LIGHT-EMITTING DIODES

摘要

A fully transparent UV LED or far-UV LED is disclosed, in which all semiconductor layers except the active region are transparent to the radiation emitted in the active region. The key technology enabling this invention is the transparent tunnel junction, which replaces the optically absorbing p-GaN and metal mirror p-contact currently found in all commercially available UV LEDs. The tunnel junction also enables the use of a second n-AlGaN current spreading layer above the active region (on the p-side of the device) similar to the current spreading layer already found below the active region (on the n-side of the device). Therefore, small-area and/or remote p- and n-contacts can be used, and light can be extracted from both the top-side and bottom-side of the device. This fully transparent semiconductor device can then be packaged using transparent materials into a fully transparent UV LED or far-UV LED with high brightness and efficiency.