Spatially resolved electron temperature measurements with a microfabricated retarding field analyzer

Electron temperature (Te) is an important parameter to quantify in the high-density plasmas commonly used in semiconductor manufacturing. Te is characteristic of the electron energy distribution which determines the plasma density and distribution of neutral and ionic species. Through application of theoretical considerations for the presheath and sheath, Te can be estimated from the ion energy distribution to a floating substrate. Utilizing microfabricated retarding field analyzers (RFAs) to measure the local ion energy distribution to a floating surface, spatially resolved Te measurements in an inductively coupled argon plasma have been made. Quantitative agreement between the RFA and Langmuir probe Te measurements was observed and the RFA Te measurements display the expected power, pressure, and spatial dependencies