Researchers at NIST’s Physical Measurement Laboratory have developed a non-destructive method to characterize graphene-insulator-semiconductor (GIS) devices using combined optical techniques. Led by Nhan Nguyen, the team has successfully determined graphene’s work function and band alignment without damaging the devices.
The method combines internal photoemission (IPE) and spectroscopic ellipsometry (SE) to measure the entire band structure of GIS devices. IPE reveals band offsets and alignments, while SE calculates band gaps. This non-destructive approach allows researchers to engineer devices with known electrical properties from the start, advancing future electronics development.
The technique’s potential impact is substantial, as it enables characterization of new semiconductor materials and complex device structures. By stacking graphene layers onto other materials with unknown properties, researchers can gain valuable insights into these layers’ behavior. This method is crucial as the industry moves beyond CMOS technology and explores more advanced materials and architectures.
Keywords: graphene, non-destructive method, band alignment, work function, internal photoemission
