Raman spectroscopy of graphene on AlGaN/GaN heterostructures

•Raman spectroscopy of graphene on (SiN/GaN)/AlGaN/GaN•Identification of number of graphene layers using Raman spectroscopy•Intensity reduction is observed in Raman spectra of graphene/AlGaN/GaN.•Substrate induced electron charge accumulation in graphene on the AlGaN/GaN•Understanding the interface properties of graphene and AlGaN/GaN heterostructures

In this paper, we report Raman mapping of graphene on AlGaN/GaN heterostructure on GaN/Si substrates. Graphene samples are prepared using exfoliation technique and transferred to AlGaN/GaN heterostructures with GaN and SiN cap layers. AlGaN induced charge accumulation is observed in graphene. Significant intensity reduction is observed in the Raman spectra in the AlGaN/GaN heterostructure peaks with graphene. We anticipate that this work provides further insights of graphene, AlGaN/GaN interfaces and can be used to further develop sensors and devices.