Cathodoluminescence in transmission electron microscopy

Abstract

We describe a cathodoluminescence spectrometer that is attached to an analytical transmission electron microscope. After a brief consideration of the set-up and the peculiarities of recording spectra and of mapping defect distributions in panchromatic and monochromatic cathodoluminescence, we discuss two examples of applications. Emphasis is placed on the potential for obtaining novel information about materials and processes on a microscopic and a nanoscopic scale by combining cathodoluminescence with the structural and chemical information for the same site of the specimen. We select an example concerning the role of In distribution in light emission from InGa/GaN quantum wells and a second one concerning the analysis of the initial electron radiation damage of Cu(In,Ga)Se(2) photovoltaic films.

Investigating the optical properties of dislocations by scanning transmission electron microscopy

“…There have also been many CL studies directly implicating dislocation cores as nonradiative recombination centers (Albrecht et al 2002;Cherns et al 2001;Ponce et al 1996Ponce et al 2003Strunk et al 2006;Yamamoto et al 2003). However it seems that many fundamental questions remain.…”

“…Identification of dislocations as sources of nonradiative recombination has been by comparison to transmitted electron images taken in the TEM or STEM, (Albrecht et al 2002;Cherns et al 2001;Lakner et al 1988;Ponce et al 1996Ponce et al , 2003Strunk et al 2006;Yamamoto et al 2003). Other methods also exist for local mapping of luminescence, for example the scanning near-field optical microscope or the scanning tunneling microscope, see Gustafsson et al (1998) for a review of these techniques.…”

Dependence of cathodoluminescence on layer resistance applied for measurement of thin‐layer sheet resistance

“…(e.g. Haegel et al , 2004; Gustafsson, 2006; Strunk et al , 2006; Diaz‐Guerra et al , 2007). An impact of long‐range effects of resistances on CL measurements has not been analysed yet.…”

Hybrid fluorescence and electron cryo-microscopy for simultaneous electron and photon imaging

“…Conventionally CL imaging has been conducted with SEM, where the CL emission from specimens is collected through the parabolic mirror to generate a scanning image. Though CL images generated with TEM were once claimed (Yamamoto 2002;Strunk et al, 2006), what was actually done was a CL imaging with the scanning mode of STEM(STEM-CL). The type of CL imaging shown in this paper must be the first one ever reported.…”