Variable-angle spectroscopic

S. A. Alterovitz, J. A. Woollam, and P. G. Snyder. Solid State Tech. 31,99, 1988. Review of use of variable-angle spectroscopic ellipsometer (VASE) for semiconductors. 

The uniformity of such an OVPD film of Alq3 is shown in Fig. 9.6. Analysis by variable angle spectroscopic ellipsometry (VASE) confirmed the surface was smooth across the entire substrate area with thickness deviation of +1.7%, a standard deviation, a, of 1.0% only. Atomic force microscopic analysis of such a typical film revealed RMS values to be 6 A, i.e. thickness differences in the range of a single monolayer only, irrespective of deposition rate [20-22]. 

To obtain the morphology information, including phase separation and crystalline, we can now use microscopic techniques, atomic force microscopy, transmission electron microscopy, electron tomography, variable-angle spectroscopic ellipsometry. X-ray photoemission spectroscopy, and grazing-incidence X-ray diffraction. The detailed information of this characterization methods can be found from the specific reference (Li et al., 2012 Huang et al., 2014). 

Muller F, Bimer A, Gosele U, Lehmann V, Ottow S, Foil H (2000) Structuring of macroporous silicon for applications as photonic crystals. J Porous Mater 7 201-204 Nassiopoulu AG, Kaltsas G (2000) Porous silicon as an effective material for thermal isolation on bulk crystalline silicon. Phys Stat Solidi (a) 182 307 Nava R, de la More MB, Taguena-Martinez J, del Rio JA (2009) Refractive index contrast in porous silicon multilayers. Phys Stat Solidi C6 1721-1724 Pettersson L, Hultman L, Arwin H (1998) Porosity depth profiling of thin porous silicon layers by variable angle spectroscopic ellipsometry a porosity graded layer model. Appl Optics 37(19) 4130 136... 

Parratt LG (1954) Surface studies of solids by total reflection of X-rays. Phys Rev 95 359 Pettersen LA, Hultman L, Arwin H (1998) Porosity depth profiling of thin porous silicon layers by use of variable angle spectroscopic ellipsometry a porosity graded-layer model. Appl Opt 37 4130... 

A Variable Angle Spectroscopic EUipsometer of the type M200-F (J.A. Woollam Co. Inc., Lincoln, USA) with a spectral range from 245 to 995 nm was used to determine the thickness of the adsorbed polymer layers. Measurements were performed in ambient at three different angles (65, 70, and 75° with respect to the surface normal). For each polymer adlayer, i.e. Sil-PEG (from toluene), Sil-PEG (from acidic aqueous solution), and PLL-g-PEG (from aqueous HEPES buffer), five samples were prepared to obtain statistical data. The measurements were fitted with multilayer models using WVASE32 analysis software. The analysis of optical constants was based on a bulk silicon/ SiOj, layer, fitted in accordance with the Jellison model. After adsorption of the molecules, the adlayer thickness was determined using a Cauchy model A = 1.45, B = 0.01, C = 0). 

ELM was performed with an M200-F Variable Angle Spectroscopic Ellipsometer (J. A. Woollam Co. Inc., Lincoln, NE) with a spectral range of 245-995 nm. Measurements were performed in air at angles of 65°,... 

In order to deposit the SBDC photoiniferter on the hydroxy-lated Si/Si02 substrates from the vapor phase, a 10 /tL drop of the photoiniferter was placed in a desiccator, which was evacuated for 60 s with a rotary vane pump to evaporate residual solvent. Thereafter, the freshly cleaned Si/Si02 substrates were placed around the SBDC drop, and the desiccator was evacuated again, this time for 60 min (p 10 mbar). After closing the valve to the vacuum pump, the photoiniferter was allowed to adsorb onto the silicon oxide substrates for > 48 h until atmospheric pressure was reached. Prior to UV-induced polymerization reactions, the photoiniferter-modified substrates were ultrasonicated in toluene for 2 min to remove physisorbed initiator before the initiator layer was characterized by variable angle spectroscopic ellipsometry and static contact-angle measurements. 

In this study we present the generation and characterization of PLL-g-PEG gradients prepared by means of an immersion process originally developed for alkanethiols [Fig. 1(b)]. Two different types of PLL-g-PEG gradients with either nonfunctionalized [Fig. 1(c)] or biotinylated PEG chains [Fig. 1(d)] were prepared on titanium and niobium oxide surfaces, respectively, and characterized by means of variable angle spectroscopic eUipsometry (VASE) and x-ray photoelectron spectroscopy (XPS). 

All single proteins were adsorbed from a 0.1 mg/ml solution in HEPES 2. Gradient and reference samples were exposed to the protein solution for 15 min, then subjected to rinsing with HEPES 2 and ultrapure water, and finally dried under a stream of nitrogen. Serum and plasma were used as received without further dilution. Variable angle spectroscopic ellipsometry measurements were carried out in a dry state. 

E. Variable angle spectroscopic ellipsometry (VASE) q. Molecular assembly patterning by lift-off (MAPL)... 

The structural regularity of the resulting NTCDI-based ultra-thin films was tested by variable angle spectroscopic ellipsometry (VASE, Woollam Co.) at 75°. Figure 6... 

Ellipsometry. Measurements were performed on a Variable Angle Spectroscopic Ellipsometer (VASE) manufactured by J. A. Woollman Co. equiped with PTI monochromator having a 4 nm bandwidth and scanned between 600 - 1000 nm at incident angles of 70, 72, 74, 76 and 78° for films between 0 A and 1275 A. Data... 

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