Polymer resists

Computers (uv and electron-beam polymer resist materials)... 

Good resistance to oils. Mainly polyisobutylene polymers resist high-oil-content foams and rubber. In some cases swelling may occur. 

Urea is sufficiently important as an additive to PF resins for OSB to warrant some discussion. It has had a large favorable economie impact on the OSB industry. When used, it is generally added after the polymerization is complete. Thus, it is not part of the polymer and does not have any direet effect on polymer resistance to hydrolysis, as might be expected if it was part of the polymer backbone. Under alkaline pH conditions, urea-formaldehyde adducts do not polymerize at a rate that is significant compared to the PF polymerization therefore, the urea does not participate signifieantly in the euring proeess of the PF, despite the faet that it is present during the cure. Since urea is not present in the cured PF polymer per se, it does not detract from the durability of the polymer. Despite this, it is possible to see redueed OSB durability as a result of formulated urea if its use has led to actual PF polymer application rates that are too low. 

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. 

Polyethylene is the most extensively used thermoplastic. The ever-increasing demand for polyethylene is partly due to the availability of the monomer from abundant raw materials (associated gas, LPG, naphtha). Other factors are its relatively low cost, ease of processing the polymer, resistance to chemicals, and its flexibility. World production of all polyethylene grades, approximately 100 billion pounds in 1997, is predicted... 

Petroleum-Soluble Polymers Resistant to Crosslinking Under Near Ultraviolet... 

It is well known that char formation during polymer burning is an important mechanism by which polymers resist burning. For example Van Krevelen (1-2) has shown that a correlation exists between the oxygen index (OI) of a polymer containing no heteroelements and the amount of char it forms when pyrolyzed in the absence of air. As shown in Table I, a similar correlation is seen to hold for a number of common engineering thermoplastics. 

VDC polymer resistance to, 25 711 of vinyl chloride, 25 631 of vitreous silica, 22 422 in vitreous silica manufacture, 22 413 in wastewater treatment, 25 889t, 892t, 893, 910-911, 911-912 Oxidation and corrosion stability (OCS) tests, 75 235... 

VDC polymer resistance to, 25 711 Small-molecule single-crystal structure determination, 26 423—425 Small molecules, mass spectrometry of, 15 666-667 Smallmouth bass aquaculture, 3 183 common and scientific names, 3 188t Small office home office (SOHO) markets, silica in, 22 376... 

Refractive index measurements made by this technique are of sufficient accuracy to make this a valuable research tool in studying and characterizing the dry etch behavior of novel polymer resist materials. In situ etch rate can be measured and analyzed quickly without any prior knowledge of the polymer s physical properties. 

The U.S. - Australia Symposium on Radiation Effects on Polymeric Materials contained research presentations on fundamental radiation chemistry and physics as well as on technological applications of polymer irradiation. This paper represents a hybrid contribution of these two areas, examining a field of extensive technological importance. Spin casting of radiation sensitive polymer resists for microelectronic fabrication was studied using photophysical techniques that are sensitive to the fundamental radiation response in the ultraviolet range. 

The irradiation of polymers is widespread in many industries. For example, microlithography is an essential process in the fabrication of integrated circuits that involves the modification of the solubility or volatility of thin polymer resist films by radiation. The sterilization by radiation of medical and pharmaceutical items, many of which are manufactured from polymeric materials, is increasing. This trend arises from both the convenience of the process and the concern about the toxicity of chemical sterilants. Information about the radiolysis products of natural and synthetic polymers used in the medical industry is required for the evaluation of the safety of the process. 

Hatzakis, U. Ting, C. Viswanathan, N. "Fundamental Aspects of E-Beam Exposure of Polymer Resists," Electron Ion Beam Science Technology, Sixth International Conference, San Francisco, May 1974. 

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.

Because of its high chemical inertia, the chemical modification of PTFE may appear as a challenge. However, although this polymer resists to acidic or alkaline attacks. 

Etch resistance data for several polymer resist systems have been reported by Taylor and Wolf O) and Moreau ( ). Some of the results are tabulated in Table I. While Taylor and Wolf (3 ) have... 

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. 

Figure 1. PE rate in A/min vs. G, jor the vinyl polymer resist systems. The etching conditions are found in Table II.

The polymer resist exhibiting the lowest PE rate or highest etch resistance versus PMMA or oxide is poly(styrene) (see Table IV). This system, like the others of Table IV, is representative of a vinyl pol3mier with general structural formula of -(CH2-CXY)-. Poly(chlorostyrene), a chlorinated derivative of the aromatic poly(styrene), exhibits equal resistance towards all three dry etch processes. Here halogenatlon has not enhanced the etch rate or reduced the resistance as seen before for PTECM, PTFEM, and PMCA nonaromatic systems. Therefore, the aromatic side group must... 

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