使用自組小球顯影技術研製氮化銦鎵/氮化鎵微米柱結構發光二極體

Fabrication and Characterization of InGaN/GaN Micro Rod Structure Light-Emitting Diode Using Self-assembled Nanosphere Lithography

林均彥(Chen-Yen Lin)

指導教授 ： 彭隆瀚

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.00226

摘要

本研究論文在探討使用自組小球顯影技術製作出氮化銦鎵�氮化鎵微米柱結構發光二極體元件與特性量測，第一部分重點在於自組小球顯影技術的原理與實施，我們成功地利用旋轉塗佈的方式在晶片上鋪設出單層緊密堆積的一微米聚苯乙烯小球，除了利用鋪設好的小球當作遮罩，再利用感應偶合電漿蝕刻出微米柱結構的氮化銦鎵�氮化鎵發光二極體，我們也在矽基板與氮化鎵基板上，利用不同的蝕刻參數，蝕刻出一微米透鏡陣列的結構，未來可應用在雷射光斑去除與發光二極體表面粗糙化等。
第二部分，我們利用實驗室成熟的光致電化學氧化層鈍化技術，搭配塗佈式玻璃材料(Spin-On-Glass)與機械化學研磨(CMP)的平坦化製程，成功完成具微米柱結構發光二極體元件製程技術之開發。在電性量測中，具氧化鈍化層之微米柱發光二極體元件漏電流，相較於未氧化之元件，在-5V時從2.358uA大幅降低到53nA；在L-I曲線中，觀察到在高電流密度下，比起平面型的元件相比，有著較高的斜率。而在電激發光輻射場型的量測中，可觀察到微米三角柱結構發光二極體在側向角度之出光上，與一般平面型發光二極體相比，具有較大角度的出光強度，遠場輻射的半強度張角從61°增加到82°，增加了21°。

關鍵字

自組小球顯影技術 ； 氮化鎵 ； 微米柱 ； 發光二極體

並列摘要

The fabrication and characterization of InGaN/GaN micro rod light-emitting diode (LED) using self-assembled nanosphere lithography are investigated in this thesis. First, we discuss the theory and process of self-assemble nanosphere lithography. We successfully use spin coating to spread out single layer close-packed 1um polystyrene spheres. The self-assembled sphere are the mask for etching InGaN/GaN micro rod LED. Moreover,we report the use of recessive size reduction in self-assembled sphere mask with reactive ion etching to from micro-lens array onto surface of Si and GaN. It can apply to laser despeckling and surface roughness.
Second, we successfully combine the chemical mechanical polishing (CMP) planarization and photoelectrochemical(PEC) pas¬sivation technique to fabricate micro rod structure light-emitting diode. Leakage current of this device with oxide passivation layer is reduced from 2.358uA to 53nA at reverse bias 5V compared to the device without oxide layer. Moreover, the radiation pattern shows that the percentage of light intensity in oblique angle of micro rod LED is higher than that of typical planar LED. The far-field radiation angle at half maximum intensity is occurs at 82°, FWHM angle is 164°.

並列關鍵字

nanosphere lithography ； GaN ； micro rod ； light-emitting diode

參考文獻

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