Low energy scanning transmission electron beam induced current for nanoscale characterization of p–n junctions. Issue 1 (29th November 2016)

• Record Type: Journal Article
• Authors: Peretzki, Patrick; Ifland, Benedikt; Jooss, Christian; Seibt, Michael
• Is Part Of: Physica status solidi. Volume 11:Issue 1(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2016-11-29
• Subjects: electron beam induced current -- p−n junction -- silicon -- strongly correlated metal oxides; Solid state physics -- Periodicals; 530.4105
• DOI: 10.1002/pssr.201600358
• Languages: English
• ISSNs: 1862-6254

Abstract

Abstract : Electron beam induced current (EBIC) at p–n junctions can be measured in high spatial resolution using a thin lamella geometry, where most incident electrons transmit the sample. We explore the case of low excitation energies in a wedge‐shaped lamella geometry to increase resolution in a controlled way. We compare a sample with high (Si) and low (manganite‐titanate heterojunction) diffusion length and use Monte Carlo based simulations as a reference. It is shown that the EBIC signal obtained from the Si junction vanishes below a thickness of 300 nm, whereas this happens at 80 nm in the PCMO–STNO junction. This allows for achieving an EBIC resolution of better than 50 nm for the latter system. The observed fundamental differences between the silicon and the perovskite junction are discussed in terms of preparation induced 'dead' layers and surface recombination. Abstract : When electron beam induced current is to be measured in high spatial resolution electron microscopy, the length scales of the involved processes play an important role. The authors use low electron energies to compare two systems with greatly different charge carrier diffusion lengths and cover the full range between transmitting and non‐transmitting electrons. Results are governed by the interplay between surface recombination and ion beam preparation damage.