Doping ellipsometry

Among the large variety of in situ experiments that have been described one can distinguish (1) those whose purpose is investigation of the electrochemical doping process itself cyclic voltammetry, quartz balance [17], mirage effect [18], and ellipsometry [19], and (2) those developed for studies of the properties of the CP UV-near-IR spectroscopy [20], IR [21], ESR [22], conductivity [23], impedence [24], and so on. 

For a polyanUine film, the light absorption measurements were conducted after the film was exposed to HCl and NH3 vapors, respectively, as shown in Fig. 14 [19]. The difference in the spectra indicated that HCl and NH3 vapors induced a different band structure and conformation of the polymer. Therefore, the optical property of the film changed when the film switched from one state (doped by HCl) to another (dedoped by NH3). The refractive index measurement by ellipsometry showed that the refractive index changed from 2.43 (doped by HCl) to 1.95 (dedoped by NH3). 

L. A. A. Petterson, F. Carlsson, O. Inganas and H. Arwin, Spectroscopic ellipsometry studies of the optical properties of doped poly(3,4-ethylenedioxythiophene) an anisotropic metal. Thin SolidPilms, 313-314, 356-361 (1998). 

Bundesmann, C. (2005) Phonons and plasmons in ZnO-based alloy and doped ZnO thin films studied by infrared spectroscopic ellipsometry and Raman scattering spectroscopy, PhD Thesis, Universitat Leipzig (Shaker, Aachen, 2006). 

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