電流分布對GaN-LED內部量子效率影響之研究

Influence of Current Spreading on Internal Quantum Efficiency in GaN-LED

周本哿(Pen-ko Chou)

指導教授 ： 劉正毓

國立中央大學/工學院/化學工程與材料工程學系/碩士(2008年)

摘要

Thin-GaN LED 為一種具前瞻性的結構，其製程需經過雷射剝離 ( laser lift-off ) 以及晶圓鍵合 ( wafer bonding ) 的步驟。相較於傳統式LED，擁有較佳的電流分布以及散熱能力，使 thin-GaN LED 結構成為高功率 LED 應用在生活照明設備的關鍵。在高電流注入之下，電流密度在 thin-GaN LED 內的分布將成為影響發光效率 ( 內部量子效率 ) 的重要因素。
傳統式 LED 的電流分布特性已經在許多文獻中被探討，電流密度隨著距離從電流注入點的增加呈現指數遞減。Thin-GaN LED 的電流分布特性至今仍未深入探討。在此研究中將會由 thin-GaN LED 電流分布特性的討論，得到電流分布長度，並利用電流分布長度計算出內部量子效率。

關鍵字

電流密度 ； 電流分布長度 ； 內部量子效率 ； 氮化鎵 ； 發光二極體

並列摘要

A promising thin-GaN light emitting diodes (LEDs) structure, different from conventional GaN-based LED, have been developed by laser lift-off (LLO) and wafer bonding processes, also have better current spreading and thermal dispersion abilities. The key application of thin-GaN LED structure is used for high-power general lighting. Under high current in-put, the current density distribution will become a significant factor to affect lighting performance (internal quantum efficiency) of thin-GaN LED chip.
The characteristics of the current spreading in the conventional wire bonded LED structure have been well studied. An exponential decrease in the current density with increasing distance away from the mesa edge was observed. Yet, for thin-GaN LED, the current spreading characteristics have not been addressed properly. In this study, we will present the current spreading characteristics of thin-GaN LED, and calculate the internal quantum efficiency (IQE) by using current spreading length.

並列關鍵字

GaN ； IQE ； LED ； internal quantum efficiency ； current spreading length ； current density

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