Curing process chamber

Figure 11.49 Effect of electron-beam curing of resists based on poly(methacrylate) platform and hybrid methacrylate/alicyclic polymer platform on polygate etch. Electron-beam curing improves etch resistance by up to 50% relative to the control (uncured) sample. Processing was done in a nitrogen environment of the ElectronCure Electron Beam Process Chamber utilizing these electron-beam parameters 3.75 keV, 6 mA, 2000 pC/cm. The wafer temperature of the standard (Std.) process was not controlled, that for the electron-beam standard cure (ESC) process was kept at a medium temperature, that for the low-temperature (LT) process was maintained at a iow temperature, whiie that for the control was at room temperature. [After R. Dammel, Practical resist processing, SPIE Short Course No. SC616 (2005).]...

Plate curing. Pallets with plates are placed in a high humidity chamber and left to cure at 35 °C for 48—72 h. During the curing process, lead in the paste is oxidized, the basic lead sulfates recrystallize and the plates are then dried to moisture content <0.5%. 

The above reactions proceed in the solid state, i.e. at slow rate. It is known that the duration of the curing process at 30—40 °C is between 48 h and 72 h, including the drying procedure. Water loss, due to formation and growth of corrosion layer, should be compensated for. That is why a RH from 40 to 75% should be maintained and air should be introduced in the curing chamber. 

The conditions for the curing process vary pending on the paste formulation and the battery applications. The curing process is often carried out using curing chambers, as shown in Figure 7.19, with controlled tanperature and humidity to ensure... 

In the production of wet process hardboards and serai-hardboards the press-dried boards are usually tempered or "cured" in hot air to increase their water resistance, dimensional stability, strenght and stiffness. A curing for 5 hours or more in hot air of 165°C is common. Higher curing temperatures reduce the period needed for each batch and thus increase the capacity of the heat treatment chamber, but they increase the auto-ignition risks. 

The unusual sensitivity of some composite-modified double-phase propellants before curing has justified intensive effort to exploit a nonmechanical mixing process. First introduced in about 1959 as the quick-mix process by Rocketdyne Division of North American Aviation (5, 10), the inert diluent process has been developed at the Naval Ordnance Station, Indian Head, Md. for application to a variety of propellant compositions. Separate streams of solids, slurried in heptane, and an emulsion of plasticizers in heptane, are combined in a non-mechanical mixing chamber. The complete propellant slurry is allowed to settle, and the heptane is separated and recycled in a continuous operation. Figure 1... 

This system involves the use of some form of heating by air or steam in a chamber in a manner such that the vulcanization occurs immediately after the rubber is formed in an extruder or calender. This is a suitable process for extruded profiles and calendered sheets and conveyor belts. Liquid curing method (LCM) is also a continuous process which involves the use of suitable hot liquid baths in which extruded profiles can be passed through and vulcanized continuously. Items can be cured rapidly at temperatures from 200°C to 300°C however the compounds must be suitably designed to prevent porosity as this is a common problem with any extrudate. Suitable materials for curing medium includes bismuth-tin alloys, an eutectic mixture of potassium nitrate and... 

The double promoter process involves the successive application of liquid promoter solutions of vinyltrichlorosilane (VTS) and 3-chloropropyltrimethoxy-silane followed by successive cure cycles in dry N2 at 90°C after each application and before photoresist application. The double promoter process evolved because it was felt that the silane reaction with the SiOH surface groups of low temperature oxides was incomplete for a single promoter application, and because vapor silane equipment did not exist at that time. Interestingly, a double HMDS liquid promoter process failed to yield adequate adhesion as well. Later in time, the successful but somewhat complex double promoter process was replaced by the vapor phase HMDS process in the Star 1000 (or 2000) then superior resist image adhesion was obtained on all four oxide substrates with all the photoresists tested. Before the advent of the HMDS vapor priming in standalone or wafer track equipment module chambers, liquid priming solutions were widely used, especially in development areas. 

This mold action permits uniform distribution of the plastics that is forced against the inside surface of the cavity. Following a prescribed cycle, the heat of the oven fuses or sinters the plastic and goes into the cooling chamber. The solidified product is removed from the mold and the cycle is repeated. This process permits molding very small to very large products. To improve product properties, hasten product densifi-cation, reduce air voids, reduce cure time, etc. 

This process simulates autoclave by using the platens of a press to seal the ends of open chamber. It provides both the force required to prevent loss of the pressurized medium and the heat required to cure the RP inside. 

Vapor deposition has been used to prepare fibers such as woven and nonwoven synthetic and natural fibers having hydrophobic/oleophobic and biocide properties. This process entails flash evaporation of a perfluoroacrylate monomer and its radiation curing in a vacuum chamber onto a selected fiber surface. 

The process of parylene polymerization is presented schematically in Figure 5.2 using parylene N, unsubstituted poly(para-xylylene). Parylene dimer is heated until it sublimes. The dimer vapor passes through a high temperature pyrolysis zone where it cracks and becomes monomer vapor, i.e., monomer is created in vacuum. The monomer polymerizes and deposits in the deposition chamber, which is usually at room temperature. Parylene polymerization completed in a vacuum is a process involving no solvents, no curing, and no liquid phase. Its use essentially eliminates concern about the operator s health and safety, air pollution, and waste disposal. 

This process is frequently used for more intricate mouldings. The thermoset powder is placed in a heated chamber, where it is liquefied and then transferred by a piston through a channel into a second mould, where the material is kept heated under pressure while the curing cycle is completed. 

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