A semiconductor light-emitting element including a semiconductor substrate having a first surface and second surface faced on the opposite side of the first surface, the semiconductor substrate having a recessed portion formed in the first surface, and the recessed portion having a V-shaped cross-section,...http://www.google.com.hk/patents/US20080006838?utm_source=gb-gplus-share專利 US20080006838 - SEMICONDUCTOR LIGHT-EMITTING ELEMENT AND MANUFACTURING METHOD THEREOF
