Nomarski interference microscopy

However, the most widely used type of interference microscopy is that giving Differential Interference Contrast (DIC), widely known as Nomarski contrast. 

Fig. 5.17. An example of secondary buckling leading to a wrinkled shape in a circular blister in a SiC thin film on a (100) Si substrate, as revealed by Nomarski interference contrast microscopy. Reproduced with permission from Argon et al.

The modern version of interference microscopy is differential interference contrast (also called Nomarski contrast, or DIG). Here again, the illumination is split into two beams, one of which is displaced at the specimen plane [1,5,6, 21]. In DIG, the beam is displaced a very small distance, much smaller than the beam diameter. The beams remain independent because the beam-splitting device is a doubly refracting crystal, producing two beams in perpendicular polarization states (see Section 3.1.7). A region... 

Absorption microscopy is the conventional transmitted-light type. Retardation microscopy includes Nomarski interference-contrast (DIC), phase-contrast and polarization. Reflection microscopy includes darkground. 

Nomarski differential interference contrast microscopy is an alternative to phase contrast microscopy which gives an almost three... 

Nomarski microscopy is an examination mode using differential interference contrast (DIC). The images that DIC produces are deceptively three-dimensional with apparent shadows and a relief-like appearance. Nomarski microscopy also uses polarized light with the polarizer and the analyzer arranged as in the polarized light mode. In addition, double quartz prisms ( Wollaston prisms or DIC prisms) are used to split polarized light and generate a phase difference. 

Microscopy with differential interference optics (e.g., Zeiss-Nomarski amplitude-contrast optics Webster et al., 1974). 

Hie most important optical technique for examining semiconductor wafer surfaces is the differential interference contrast microscopy method of Nomarski (N-DIC). First described in 1952, DIG... 

To understand the release mechanism, cryomicrotomy was used to slice 10 m-thick sections throughout the matrices. Viewed under an optical microscope, polymer films cast without proteins appeared as nonporous sheets. Matrices cast with proteins and sectioned prior to release displayed areas of either polymer or protein. Matrices initially cast with proteins and released to exhaustion (e.g., greater than 5 months) appeared as porous films. Pores with diameters as large as 100 /xm, the size of the protein particles, were observed. The structures visualized were also confirmed by Nomarski (differential interference contrast microscopy). It appeared that although pure polymer films were impermeable to macromolecules (2), molecules incorporated in the matrix dissolved once water penetrated the matrix and were then able to diffuse to the surface through pores created as the particles of molecules dissolved. Scanning electron microscopy showed that the pores were interconnected (7). 

An even more refined method of study is interference-contrast microscopy [following Nomarski (767)] which converts minute topographical differences into color changes. Replica electron microscopy (77), gold decoration (see Section III,A,1), and scanning electron microscopy are also useful but less practicable. Occasionally it is profitable to follow the course of the reaction, in situ, using time-lapse cinematography (77). 

Nomarski microscopy Differential interference contrast microscopy utilizes differences in refractive index to visuahze structures producing a nearly three-dimensional image. 

Nomarski Differential Interference Contrast (DIC). In 1955 the physicist George Nomarski simplified the two-beam interference microscope in a way that it became available for routine microscopy [11 (Fig, 6), DIC uses modified Wollaston prisms (Fig. 6B). lying outside the focal... 

R. D. Allen el al. The Zeiss Nomarski Differential Interference Equipment for Transmitted-Light Microscopy. Z. Wiss. Mikrosk. Mikrosk. Tech, 69 (1969) I93-22I. 

W. Lang Nomarski Differential Interference Contrast Microscopy. Zeiss Inf. 16 (1968) no. 70, 114-120. 

Another technique for crystallinity analysis is the measurement of pole figures. It is widely applied for thin films, LPE films, melt-processed polycrystalline samples with a noticeable texture (Goyal et al. 1993). In fig. 33, a good crystallinity of the Y123 LPE film is evidently obtained due to a specific growth mechanism, mentioned above (sect. 5.4), despite the large misfit between the film and the MgO substrate. Differential interference contrast (DIM or Nomarski) microscopy can be successfully applied to observe misorientation on flat ( mirror-like ) surfaces (Klemenz and Scheel 1993). 

Figure 31.2 Observation by differential interference contrast (Nomarski) fluorescence optical microscopy of the transformation from a tubular structure to an oligovesicular structure of phospholipid (A) suspended in a phosphoric buffer (T = 298 K, pH = 7.0, = 485 nm,...

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