کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1792297 | 1023640 | 2011 | 4 صفحه PDF | دانلود رایگان |
The surface of a non-polar a-plane GaN light-emitting diode (LED) was intentionally damaged with a KOH wet etch to enhance the extraction of light. This roughening technique has been commonly applied to c-plane polar GaN LEDs to extract photons that would otherwise suffer from total internal refraction. We show that wet etching of the non-polar LED does create a textured surface that increases the light extraction efficiency; however, the mechanism of the etch is quite dissimilar to the etch mechanism observed for c-plane LEDs. In fact, the etch proceeds perpendicular to the a-plane surface along unstable N-face (0 0 0 −1) plane with the Ga-face plane resistant to the etch. The photoluminescence intensity from a-plane non-polar LED after KOH-based wet etching was increased by 83% in our experiments. Therefore, surface roughening by KOH-based wet etch was found to be very effective to extract photons from a-plane non-polar GaN-based LEDs.
Journal: Journal of Crystal Growth - Volume 326, Issue 1, 1 July 2011, Pages 65–68