Study of Mg Doping Profile in InGaN-GaN Light-Emitting Diodes with AlGaN Electron-Blocking Barrier

• Main Authors: Shin-Hau Chen, 陳信豪
• Other Authors: Guo-Mei Wu
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/22468066343905144296

碩士 === 長庚大學 === 電子工程研究所 === 94 === Abstract The blue InGaN–GaN multiple quantum well light-emitting diodes (LEDs) were grown on sapphire substrates using metal–organic vapor phase epitaxy system. The Mg-doped AlGaN electron-blocking (EB) barrier was introduced under various Cp2Mg flow conditions at high temperature (1050℃). The characterization included current-voltage analysis, electro-luminescence and photo- luminescence. Secondary-ion-mass spectrometry (SIMS) revealed the Mg doping profiles close to the QW active region. The profile was found to be influenced by segregation as well as by diffusion during growth. The increased Mg concentration resulted in improved hole injection and carrier concentration. This has been in accordance with the increased EL efficiency, luminous intensity, and lower forward voltage. X-ray diffraction study showed the full-width at half-maximum (FWHM) of 264-290 arcsec for GaN (0002) and 313-326 arcsec for GaN (10ī2). In addition, the luminous output power of LED with the higher growth temperature (1050℃) for the Mg-doped AlGaN barrier was 1.5 times greater than that of the lower growth temperature (1025℃) samples. The experimental results will also be compared with literature data in great details.