LED的P型電極對輸出光功率的影響

我們已成功的研製出高功率大面積（ie: 1mm 1mm）Ni/Au和Ni/ITO P型電極之氮化鎵系列發光二極體（LEDs）。輸入電流在200mA時，高功率Ni/Au和Ni/ITO發光二極體順向電壓分別為3.19V和3.3V。另一方面，對於高功率Ni/Au P型電極的LED，雖然在電流200mA時其輸出功率只有11.59mW，但是以Ni/ITO作為P型電極的高功率LED，在電流200mA時輸出功率則可達到16.52mW。如此明顯的增加趨勢主因是，Ni/ITO比起Ni/Au具有更優異光穿透性（Transparency）。在可靠度（Reliability）測試結果也可以看出，以Ni/ITO及Ni/Au的高功率發光二極體同具有不錯的耐壽性。

Large size (i.e. 1mm×1mm) high power nitride-based light emitting diodes (LEDs) with Ni/Au and Ni/indium tin oxide (ITO) p-contacts were fabricated. It was found that the 200mA forward voltage was 3.19V and 3.3 V for the power LEDs with Ni/Au and Ni/ITO p-contacts, respectively. On the other hand, although the 200mA output power was only 11.59mW for the power LED with Ni/Au p-contact, the 200mA output power could reach 16.52mW for the power LED with Ni/ITO p-contact. Such a significant increase could be attributed to the more transparent nature of Ni/ITO, as compared to Ni/Au. Preliminary life test also indicates that power LEDs with Ni/ITO p-contact are at least as reliable as power LEDs with Ni/Au p-contact.