It has been known for more than 60 years, and suspected for over 100, that alveolar hypoxia causes pulmonary vasoconstriction by means of mechanisms local to the lung. For the last 20 years, it has been clear that the essential sensor, transduction, and effector mechanisms responsible for hypoxic pulmonary vasoconstriction (HPV) reside in the pulmonary arterial smooth muscle cell. The main focus of this review is the cellular and molecular work performed to clarify these intrinsic mechanisms and to determine how they are facilitated and inhibited by the extrinsic influences of other cells. Because the interaction of intrinsic and extrinsic mechanisms is likely to shape expression of HPV in vivo, we relate results obtained in cells to HPV in more intact preparations, such as intact and isolated lungs and isolated pulmonary vessels. Finally, we evaluate evidence regarding the contribution of HPV to the physiological and pathophysiological processes involved in the transition from fetal to neonatal life, pulmonary gas exchange, high-altitude pulmonary edema, and pulmonary hypertension. Although understanding of HPV has advanced significantly, major areas of ignorance and uncertainty await resolution.

Hypoxic pulmonary vasoconstriction.

Spin-coating is widely employed for the highly reproducible fabrication of thin film coatings over large areas with high structural uniformity. Research in recent years has extended the scope of spin-coating by chemically engineering the interface of support and solution to obtain specific structural order in the resulting supported thin films. This review will discuss both the fundamental physical and chemical processes governing the conventional spin-coating process and describe methodologies for the preparation of spin-coated polymer thin films. Furthermore, a range of advanced applications and recent developments within this field will be reviewed with focus on engineering chemical and topological structure during the coating process.

6 Studies of spin-coated polymer films

The process of spin coating is described, with particular attention to applications in microelectronics. The physical mechanisms involved in the process are discussed and those mechanisms that affect the final state are identified, viz., centrifugal and viscous forces, solute diffusion, and solvent evaporation: A model is proposed that incorporates only the latter mechanisms, with viscosity and diffusivity depending on solute concentration. The evaporation of solvent during spinning causes the solution viscosity to increase and the flow is reduced. The thickness of the final solid film is related to the thickness of a diffusion boundary layer near the free surface. The model predicts the final dry film thickness in terms of the primary process variables, spin speed, and initial polymer concentration. A similarity boundary‐layer analysis leads to a simple approximate result for the final film thickness that is consistent with limited experimental data, hf ∼KC0(ν0D0)1/4/Ω1/2, where K is a number of order un...

The mechanics of spin coating of polymer films

A mathematical model is derived to elucidate the dominant mechanism governing film formation. It leads to a relation between film thickness and film radius spreading with time. Inclusion of evaporation and shear stress was made with extension to non-Newtonian fluid. The advantages and disadvantages of this process with applications are reviewed.

Fundamental understanding and modeling of spin coating process: A review

Introduction.-Solution Chemistry Simple alkoxide based precursor systems Carboxylate based precursor systems Single-source precursors Acqueos Precursor Systems Solution Synthesis Strategies.-Analytical Methods Introduction Thermal Analysis NMR Sepctroscopy EXAFS Other Methods (XRM, SEM,TEM scattering methods at nanocrystalline films) Spin-Coating Dip Coating Inkjet Printing and Other Direct Writing Methods(dip point and imprint techniques) Chemical Bath Deposition Polymer Assisted Deposition.-Processing and Crystallization Thermodynamics and Heating Processes Material Systems Dominated by Heterogeneous Nucleation Material Systems Dominated by Homogeneous Nucleation Low Temperature Processing Epitaxial Films Powder Assisted Film Fabrication UV-and E-Beam Direct Patterning of Photosensitive CSD Films Template Controlled Growth.-Functions and Applications Introduction Integrated Capacitors Base Metal Electrodes Polar Oxide Films for MEMS Applications Conducting Films and Electrodes Transparent conducting oxides Superconducting Films Porous Films for Gas Sensors Luminescent Fims.-Appendix Synthesis for Standard material Systems.

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Chemical Solution Deposition of Functional Oxide Thin Films

The success of lithographic processes in microelectronics fabrication depends on the reproducible generation of desired polymer resist film thickness and profile uniformity. Numerous process variables affect the outcome of spin coating of resists on wafers. A thorough understanding of the intricate interdependence of process parameters is essential to guide future process design and improvement. A mathematical model is derived to elucidate the dominant mechanisms governing film formation. The non‐Newtonian character of the resist solution is taken into account, as well as the changes in resist viscosity and solvent diffusivity with changing polymer concentration. Results obtained from this model show that polymer film thickness is controlled by convective radial flow of the resist solution and solvent evaporation. The former process governs film thickness during the early stages of the process, while the latter becomes significant in later stages. The model accurately describes the experimentally observed dependence of film thickness on the variables affecting the spin‐coating process.

A mathematical model for spin coating of polymer resists

Application d'un ellipsometre simplifie (psi-metre) a la mesure in situ de l'epaisseur d'un film de resist dans des solutions de revelateur

Warren W. Flack

Papers

A mathematical model for spin coating of polymer resists

In Situ Measurement of Resist Dissolution with a Psi‐Meter