Applications of depth-resolved cathodoluminescence spectroscopy

Abstract

Depth-resolved cathodoluminescence spectroscopy (DRCLS) has developed over the past few decades into a powerful technique for characterizing electronic properties of advanced materials structures and devices on a nanoscale. The lateral and depth-resolved capabilities of DRCLS enable researchers to probe native defects, impurities, chemical changes and local band structure inside state-of-the-art device structures on an unprecedented scale. A key strength of DRCLS is its ability to distinguish electronic features at buried interfaces within multilayer device structures, interfaces whose microscopic physical features can determine macroscopic electronic properties. This review provides a general overview of DRCLS and illustrates the wide array of applications now available using this technique.

Depth-resolved cathodoluminescence spectroscopy of silicon supersaturated with sulfur

“…14 The inhomogeneous doping makes it challenging to study the relationship between band structure and S concentration through bulk characterization; so far, iterative characterization and etching have been needed to characterize how material properties change with depth and thus with S concentration. 14,17 In this study, we combine depth-resolved cathodoluminescence (CL) spectroscopy [18][19][20] and secondary ion mass spectroscopy (SIMS) to investigate the relationship between luminescence and dopant concentration in Si doped with S to beyond-equilibrium concentrations. A sulfur-related subband gap luminescence is reported at 0.85 eV, distinct from the S-related luminescent centers previously observed at dilute S concentrations.…”

Impact of Mg content on native point defects in MgxZn1−xO (0 ≤ x ≤ 0.56)

“…DRCL spectra in this energy range display near band edge (NBE) and band-to-defect level transitions with nanometer depth resolution. [23][24][25] Depth dependence of electron-hole excitation was modeled using Monte Carlo simulations. 26 For E B = 1, 2, 3, 4, and 5 keV, excitation peaks at depths U 0 = 7, 18, 32, 50, and 72 nm, respectively, with Bohr-Bethe maximum range R B ∼ 3x longer.…”

Low-energy Cathodoluminescence for (Oxy)Nitride Phosphors

“…Such core-surface distribution is observable with CL by changing the electron energy, since it varies the penetration depth of the incident electrons 21 . However, the penetration depth varies for each material and the correspondence between electron energy and penetration depth is not linear, and may introduce some additional effects, such as the reabsorption of higher energy photon from the deeper regions by the material itself.…”