Coatings polymer resist

High adhesion and sensitivity to UV irradiation of these polymer coatings allow one to use them as a base for the preparation of polymer resistance of a negative type. 

Some polymers like PE and NR get cross-linked on exposure to radiation while others like those based on vinylidene polymers, e.g., polymethylmethacrylate (PMMA), polyisobutylene, degrade. Certain other types of polymer stmctures (high aromatic content or thermoset) resist degradation by high-energy radiation. Coating polymers usually contain acrylic, methacryUc, or fumaric vinyl unsaturation along or attached to the backbone. 

Figure 15. A typical thermogravimetric analysis (TGA) trace of a polymer resist that has been spin-coated and NOT prebaked. The small weight loss at low temperature is due to solvent evaporation and the high temperature weight loss is due to thermal decomposition.

Figure 16. A typical differential thermal analysis (DTA) trace of a polymer resist that was spin coated and not prebaked.

The polymer resists used in this study were either synthesized in-house or obtained from Aldrich Chemicals or Polyscience, Inc. Photoresist samples were obtained from KTI Chemicals or the manufacturer. The polymers were dissolved in suitable solvents and spin coated onto oxidized Si wafers or Cr-coated glass test substrates. The polymer film thicknesses were measured either by a Taylor-Hobson proficorder or Tencor Alpha-step. 

Title Polymer, Resist Protective Coating Material, and Patterning Process... 

Wang, Z., Han, E., and Ke, W. 2006. Effect of acrylic polymer and nanocomposite with nano-Si02 on thermal degradation and fire resistance of APP-DPER-MEL coating. Polymer Degradation and Stability 91(9) 1937—1947. 

The first step was to spin-coat an electron-sensitive polymer (polymethylmethacrylate (PMMA)) onto an oxidized Si(l 00) wafer (which serves as a Si02 support). The desired pattern is subsequently written into the polymer layer by a highly collimated electron beam, followed by the selective dissolution of the polymer damaged by the electron exposure. A thin film of platinum is then deposited on this mask, and after the remaining polymer resist is removed completely by dissolution, metal particles remain on the substrate and are located at the positions of the prior electron irradiation, typically forming an ordered array of nanoparticles. 

Due to the inherent dry nature of CVD technique, CVD polymers can be utilized as dry resist coatings. Dry resist lithography is advantageous over conventional wet resist techniques because, the whole process can be performed in a unified vacuum chamber. The... 

Coating organic polymer films with lecithin can improve the release properties of the film from the crimp jaws of the automated packaging machine (441). In analytical equipment, lecithin is used to improve the wettability of the contact surface, which enables the solvent to be presented uniformly for analysis (442). Incorporation of lecithin in a masking application can reduce bubble formation and improve the uniformity of the apphcation (443). And finally, lecithin can be used as a protective coating for a painted surface such as found on automobiles. Once applied, it facilitates the removal of insects and debris. The coating is resistant to rain and washing away (444). 

Application of non-contact mode AFM in anodic oxidation based lithography is an important step forward in this field [76]. Noncontact AFM has been used to create feature sizes <30 nm on a 65 nm resist (polymer resist) and was transferred through reactive ion etching (RIE) to the Si substrate (P-doped (100)) on which the resist is coated [77]. A scan speed of 10 pm s has been achieved using a heavily B-doped Si cantilever with a large spring constant ( 340 N m ) and mechanical resonance frequency ( /) MHz) and with a tip of radius of curvature... 

Fig. 12 Schematic of (A) building 3D polymer nanostructures by using reverse-imprint thermal plastic or photosensitive material is spin-coated on the mold for pattern transfer and (B) infiltrate the 3D periodic structure with other materials, such as inorganic materials that have high refractive index then remove the polymer template layer to create a 3D pattern of the infiltrated material that is complementary to the original polymer resist pattern. (View this art in color at www.dekker.com.)...

Major polymer applications silicon wafer carriers, pump, pipes, fittings, filtration, tubing, column packing, marine coatings, wear resistant products, coating for hostile environments, automotive weather seals for doors and windows... 

Plastics and elastomers are generally thought to be resistant to or unaffected by mild environments such as water Immersion. Commonly, an organic coating polymer or seal Is accepted as providing a water-tl t barrier even when the device Is Immersed In water. But water will permeate the barrier. If only slowly. The phenomenon of water permeation Is reviewed In (1,2). 

Although the consumption of these materials in aerospace is but a small fraction of the resinous polymers used in industry, the impact of the needs and applications is large. Virtually all modern day structural adhesives have aerospace origins. The need for elevated temperature performance resulted in polymers useful for such diverse applications as electrical insulation and brake linings. The search for coatings to resist rain errosion and UV light contributed heavily to the technology of the polyurethanes. 

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