Submicron images

Figure 8. Self developed submicron images produced in a film of poly(p-t-butylphenyl methylsilane) by irradiation at 248 nm (55 mJ/cm -pulse, 550 mJ total dose). The images were transferred into 2.0 /im of a hard baked AZ photoresist by O2-RIE.

Curing of epoxy resins can be initiated photochemically by release of imidazole from photolabile protected derivatives, such as AT-(2-nitrobenzyloxycarbonyl)imi-dazole. Positive working polyimide resists derived from 2-nitro-p-xylyleneoxy-amine have been synthesized and studied and 2-nitrobenzyloxy derivatives are included in a formulation for submicron imaging. ... 

Sundarajan, S. Yang, K. Ogino, S. Valiyaveetil, J. Wang, X. Zhou, C.K. Ober, S.K. Obendorf, and R.D. Allen, Supercritical CO2 processing for submicron imaging of fluoropolymers, Chem. Mater. 12, 41 (2000). 

The characterization of biomolecules and biological systems on solid surfaces is of major importance for a wide range of innovative products such as biomaterials, biosensors, and for several applications in medicine. Because of its high surface sensitivity and submicron imaging capability of molecular species, ToF-SIMS has been used to characterize a variety of biomolecules and biological systems. The relevant literature on ToF-SIMS of biomolecules and biological systems is briefly reviewed in this section. 

With its ability to provide molecular information and submicron imaging resolution, ToF-SIMS is an ideally suitable analytical technique for the characterization of polymer blends. Indeed, it is the only technique that is able to provide both chemical composition and morphology information. The apphcations of ToF-SIMS to polymer blends cover the two main research areas cited above, namely surface composition and morphology. 

Figure 12. Submicron images (400 nm) formed in NOVOBOC with dose of 8.5...

Figure 13. Submicron images of 500 nm formed by electron beam dose of 3...

Since alkyl-silicon bonds are known to be much more resistant to acidolysis than aromatic-silicon bonds, p-trimethylsilylmethylphenol has been condensed with formaldehyde (20), and terpolymers with m-cresol give good etch resistance and good images. Resorcinol-based novolac resins that contain silicon connected via an alkyl ether linkage (21) are also stable to the acidic polymerization conditions. These polymers are also reported to yield submicron images and to function in a bilayer mode. 

Examples of semiconductor applications include the imaging of surface coatings to determine uniformity and the imaging of submicron processed features. 

Figure 10. Submicron features generated by e-beam imaging of 0.14 ftm of an aliphatic polysilane over 2.0 ftm of hardbaked Novolac-naphthoquinone-2-diazide photoresist 20 ftC, Oj-RIE image transfer.

Core-shell colloidal crystal films were prepared in three steps as outlined in Table 4.2. First, spherical submicron polystyrene particles were prepared by known methods38 39. The size of isolated polystyrene beads was 326 5 nm as determined by analysis of scanning electron microscopy (SEM) images using standard techniques. 

Fig. 4.2 TEM images of fabricated nanoparticles, (a) Isolated composite core/shell submicron particles, (b) Hollow silica submicron particles prepared by removing the polystyrene core to demonstrate the high quality of the formed sol gel shell of the composite nanospheres employed to prepare sensing colloidal crystal films...

Fig. 4.3 SEM images of the long range packing assembly of composite colloidal crystal array films assembled on different substrates (a) polycarbonate sheet, (b) Teflon sheet, and (c) Teflon film. The submicron particles were composed of 326 nm diameter polystyrene beads coated with a 20 nm thick Si02 shell. Scale bars in (a c) are 3.00, 3.00, and 2.72 pm, respectively...

In the literature these studies are classified as imaging mass spectrometry (IMS) and defined as the investigation of the chemical profile of a sample surface with a submicron lateral resolution and chemical specificity. The main aim is to use the power of mass spectrometry techniques to create chemical images showing the distribution of compounds ranging in size from atomic ions and small molecules to large proteins. 

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