Enhanced ferromagnetism by preventing antiferromagnetic MnO2 in InP:Be/Mn/InP:Be triple layers fabricated using molecular beam epitaxy

The p-type InP:Be/Mn/InMnP:Be triple epilayers were prepared using MBE to increase Tc (>300 K) by preventing MnO2. After milling 1–3 nm of epilayers thickness from the top surface, the transmission electron microscopy (TEM) and X-ray diffraction (XRD) revealed no MnO2 and precipitates, and TEM and XRD results coincide with results of ferromagnetism. The enhanced ferromagnetic transition at >300 K corresponds to InMnP:Be. The increased ferromagnetic coupling without MnO2 is considered to originate from the increased p–d hybridation. These results demonstrate that InP-based ferromagnetic semiconductor layers having enhanced ferromagnetism can be formed by above process. •We report characteristics for the p-type InP:Be/Mn/InMnP:Be triple epilayers which persists above Tc: 300 K.•InMnP:Be epilayers annealed at 250 °C for 30 min with the Mn concentration of 1%.•The double cross-check of transmission electron microscopy and X-ray diffraction did not MnO2 and any precipitates.•Enhanced Tc is caused by the prevention of antiferromagnetic MnO2 above.•Mechanism of ferromagnetic semiconductor is originated from intrinsic InMnP:Be mediated by hole.