소개글
[신소재공학] GaN LED 투명 전극 실험(영문)에 대한 자료입니다.
목차
1.Abstract
2.Introduction
3.Ag(5nm)/Graphene
4.Measuring Contact Resistance
5.Ni-patterned layer
6.Experiment
7.Conclusion
8.Future Work
본문내용
We investigated graphene-based transparent electrodes for InGaN/GaN light emitting diodes(LED). Nano-dotted layer of Ag and Ni were inserted between p-GaN and graphene to achieve low contact resistance and high transmittance. Heat treated Ag layer/graphene had low contact resistance of 0.7~1.2Ω/cm2, and we could achieve better luminance for GaN-based LED. However, for patterned Ni layer/graphene electrode, we failed to measure the contact resistance.
Structure of GaN based LED : ‘Top emission’ and ‘Vertical’ structures
Since achieving heavily doped p-GaN is difficult, it is hard for p-GaN in top emission LED to spread the current from the p-electrode, which results in low intensity of LED.
Therefore, transparent ohmic contact to p-GaN with low resistance is essential for
achieving GaN-based LED with better efficiency.
Desired : Low contact resistance to p-GaN and High transmittance.
① Metal layer
☞ Low Contact Resistance, but Low transmittance
② Graphene layer☞ Excellent Transmittance, but High contact resistance
③ Metal/Graphene layer to p-GaN☞ Improved contact resistance, but not quite high transmittance.