||In the study, we investigated Zinc oxide nanorods by hydro-thermal contact to GaN blue LED and compared with AZO and Ni/Au thin film. Zinc nitrate and Hexamethylenetetramine were used as the deposition precursors. |
We investigated transmission and Hall effect of AZO and Ni/Au transparent conducting film, and applied to the chip process of GaN blue LED. Ni/Au was more good ohmic contact than AZO on P-GaN, but that transmission of AZO was high, thus, light output power of AZO LED was more higher than Ni/Au LED, so that can improve properties of LED.
In order to further increase the light output power, ZnO nanorods was surface roughness by hydro-thermal on AZO film, that analyed transmission and surface of different concentrate and growth time, and applied to GaN blue LED. The optimum of transmission was 93.71% in 0.04M concentrate of Zinc nitrate and 30minutes of growth time at 454nm.The optimum of light output power was 90 minutes of growth time on ZnO nanorods, that Pattern(2) of light out power was more 126.1% than Pattern(2) of AZO LED at 100mA.
The escape probability of photons generated in active layer of LED can be enhances by slim, irregularly and roughness of ZnO nanorods. Although, that was bad ohmic contact between AZO film and P-GaN, but the result of ZnO nanorods on AZO can effecticely improve light output power of LED, and thus enhance the light extraction efficiency.