“…The very low detection limits possible with WDX also allow the analysis of trace elements (Ritchie et al, 2012; Batanova et al, 2018; Vind et al, 2018) with concentrations on the order of 10 ppm (Donovan et al, 2011) being quantifiable. These same principles have then been applied to semiconductor characterization; using WDX to determine and map the composition of the main semiconductor material and trace element analysis to quantify material dopant densities and identify undesired impurities (Nakajima et al, 1978; Bejtka et al, 2008; Kusch et al, 2017). While there are more established techniques used to determine doping concentrations, such as secondary ion mass spectrometry (SIMS; Chu et al, 1998), WDX benefits from being nondestructive and allowing simultaneous acquisition of other characteristic signals such as cathodoluminescence (Lee et al, 2005; Pownceby et al, 2007; Edwards & Martin, 2011).…”