摘要
An ultraviolet (UV) laser lift-off (LLO) technique was presented to form a roughened surface morphol-ogy on GaN membrane grown by metalorganic chemical vapor deposition (MOCVD). The etched sur-face showed cone-like structures on a free-standing GaN membrane. Based on the scanning electron microscopy (SEM) and atom force microscopy (AFM) measurements, the etching mechanism was proposed, which was related to the different decomposition depth caused by the dislocations in the GaN membrane. The etching efficiency and morphology of GaN by the LLO technique and the photo-electrochemical (PEC) wet etching technique was compared and analyzed. This roughed cone-like surface morphology by LLO can enhance the external efficiency of vertical structure n-side-up GaN-based light-emitting diodes (LEDs) simultaneously while being released of the performance con-strains impeded by sapphire.
An ultraviolet （UV） laser lift-off （LLO） technique was presented to form a roughened surface morphology on GaN membrane grown by metalorganic chemical vapor deposition （MOCVD）. The etched surface showed cone-like structures on a free-standing GaN membrane. Based on the scanning electron microscopy （SEM） and atom force microscopy （AFM） measurements, the etching mechanism was proposed, which was related to the different decomposition depth caused by the dislocations in the GaN membrane. The etching efficiency and morphology of GaN by the LLO technique and the photoelectrochemical （PEC） wet etching technique was compared and analyzed. This roughed cone-like surface morphology by LLO can enhance the external efficiency of vertical structure n-side-up GaN-based light-emitting diodes （LEDs） simultaneously while being released of the performance constrains impeded by sapphire.
基金
Supported by the National High Technology Research and Development Program of China (Grant No. 2004AA311030)
State Key Program of Basic Research of China (973) (Grant No. 20000683-02)
Beijing Municipal Education Commission (Grant No. 2002kj018, Grant No. kz200510005003)
Beijing Municipal Science and Technology Commission (Grant No. D0404003040221)
