In situ X-ray fluorescence used for real-time control of CuInxGa1−xSe2 thin film composition

Process Diagnostics and Coating Characteristics

“…Because X-rays are material dependent, the composition of compounds can be determined. This makes this a measurement suitable for use in measuring coatings used for photovoltaics such as copper indium gallium diselenide (CIGS) [63,64]. As the deposition of these materials is often carried out at high temperature, the XRF measurement system needs to be protected and positioned somewhere where the temperature is lower, preferably below 200 C. The system can also be sensitive to contamination by selenium, which is one of the most difficult materials to control in the system with the vapor often migrating throughout the system.…”

In Situ Sensors for CIGS Deposition and Manufacture

“…11,12 Examples of composition and thickness data taken in situ with XRF on a 40 foot test section of stainless steel substrate at Global Solar Energy are shown in Figure 2. Product sensors for CIGS co-evaporation currently include X-ray fluorescence (XRF) -XRF measurements are performed by illuminating a portion of a sample with x-rays, and then measuring the energy and count rate of the fluoresced x-rays.…”

Rapid quantitative analysis of elemental composition and depth profile of Cu(In,Ga)Se2 thin solar cell film using laser-induced breakdown spectroscopy

“…For rapid quantitative analysis of CIGS thin film, X-ray fluorescence (XRF) is one of the available technologies under use [2]. Whereas depthwise elemental grading is known to be important for high efficiency CIGS solar cell [3], XRF can provide average composition only with a limitation in detecting light trace elements such as Na.…”