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Current spreading of III-nitride light-emitting diodes using plasma treatment Hsin-Ying Lee Ke-Hao Pan Chih-Chien Lin Yun-Chorng Chang Fu-Jen Kao Ching-Ting Lee Outline Introduction Experiment Results and Discussions Conclusions References Introduction 大部分傳統LED，都會發生因電極關係，造成在電極 下，電子電洞複合所產生的光，都會因電極不透光，而造 成在電極下的光都會被遮住，使LED整體亮度下降很多。 光 電極遮光 Current Blocking Layer P ITO CBL P-GaN MQW N-GaN sapphire CBL Refer N Experiment 300 × 300μm2 Structures of (a)LED A with CF4+O2 plasma treatment and (b)LED B without plasma treatment. Results and Discussions Current-voltage characteristics of Ni/Au contact with various plasma-treated ntype GaN. plasma treatment without plasma treatment Current-voltage characteristics of LED A and LED B. plasma treatment without plasma treatment Reverse current as a function of reverse voltage of LED A and LED B. plasma treatment without plasma treatment about 16% Light output power–current characteristics of LED A and LED B. Far-field light emission distribution of (a) LED A and (b) LED B injected with pulse current of 200 mA pulse width=100 s and repetition frequency=1kHz. Improvement in the Light Output Power of GaNBased Light Emitting Diodes by Natural-Cluster Silicon Dioxide Nanoparticles as the Current Blocking Layer Chun-Fu Tsai Yan-Kuin Su Chun-Liang Lin 350 × 430μm2 Schematic cross-sectional view of the epitaxial layers and GaN LED fabricated with SiO2 nanoparticle CBL. SEM images of (a) the morphology of p-GaN surface, (b)the SiO2 nanoparticles with ~20nm diameter, (c) SiO2 nanoparticles cluster naturally in p-GaN surface pits, and (d) CBL pattern formed on p-GaN with SiO2 nanoparticles. CCD images of (a) fabricated chip with size 350 × 430μm2, (b) the SiO2 nanoparticles CBL beneath Cr/Pt/Au pad. CBL-3.34V Ref -3.29V I-V and L-I characteristics of the reference and SiO2 nanoparticles CBL LEDs. about 15.7% Room temperature EL spectra of the reference and SiO2 nanoparticle CBL LEDs at 20 mA dc injection current. Conclusions 傳統LED製作CBL，可以有效的改變LED的電流路徑， 使其電流不通過P電極下方，可以有效的改善電極遮光的 問題，但在大電流操作下，容易造成電流聚集，使整體溫 度上升造成LED特性降低。