Influence of an InGaN superlattice pre-layer on the performance of semi-polar (11–22) green LEDs grown on silicon

• Published in: Scientific reports 2020-07, Vol.10 (1), p.12650-12650, Article 12650
• Main Authors: Zhao, X., Huang, K., Bruckbauer, J., Shen, S., Zhu, C., Fletcher, P., Feng, P., Cai, Y., Bai, J., Trager-Cowan, C., Martin, R. W., Wang, T.
• Format: Article
• Language: English
• Subjects: 639/301; 639/624; Humanities and Social Sciences; Light emitting diodes; Misfit dislocations; multidisciplinary; Recombination; Science; Science (multidisciplinary); Silicon
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-69609-4

It is well-known that it is crucial to insert either a single InGaN underlayer or an InGaN superlattice (SLS) structure (both with low InN content) as a pre-layer prior to the growth of InGaN/GaN multiple quantum wells (MQWs) served as an active region for a light-emitting diode (LED). So far, this growth scheme has achieved a great success in the growth of III-nitride LEDs on c-plane substrates, but has not yet been applied in the growth of any other orientated III-nitride LEDs. In this paper, we have applied this growth scheme in the growth of semi-polar (11–22) green LEDs, and have investigated the impact of the SLS pre-layer on the optical performance of semi-polar (11–22) green LEDs grown on patterned (113) silicon substrates. Our results demonstrate that the semi-polar LEDs with the SLS pre-layer exhibit an improvement in both internal quantum efficiency and light output, which is similar to their c-plane counterparts. However, the performance improvement is not so significant as in the c-plane case. This is because the SLS pre-layer also introduces extra misfit dislocations for the semi-polar, but not the c-plane case, which act as non-radiative recombination centres.