Vacuum chamber configurations

From a sample preparation point of view, it must be remembered that several of the methods may require processing in vacuum, which implies remote sample handling and manipulation from outside the test chamber. There is a wide variety of intricate commercial instrumentation available for this step, and most designs allow additional customization, depending on vacuum chamber configuration. 

There are several types of deposition chamber configurations (Fig. 2). The batch-type system is the most commonly used, but the requirement that the system be returned or let-up to ambient pressure on each cycle can pose problems in obtaining a reproducible processing environment. The load-lock system and the in-line system allows the deposition chamber to be kept under vacuum at all times and the substrates introduced and removed through... 

Fig. 2. Vacuum processing chamber configuration (a) batch coater (b) load-lock coater (c) in-line coater (d) cluster tool (e) roU coater (batch) and (f) roU coater (air-to-air), [[ccsq]] represents the isolation valve with transfer tooling [[artl]], the motion of fixturing and [[art2]], the access door.

Qualitative or quantitative mass spectrometric analysis can be made by one of two alternative configurations. Either the sample is decomposed in the high vacuum chamber of the mass spectrometer (MS) itself or reaction proceeds in an external system at higher pressure (e.g. a microbalance)... 

Figure 6 Vacuum chamber ofthe Terawatt Ultrafast High Field Facility (TUHFF) at ANL, configured for a measurement of electron beam energy dispersion (courtesy of R. Crowell).

There are two basic types closed-cycle and open-cycle. In a closed-cycle system, warm surface seawater and cold deep seawater are used to vaporize and condense the working fluid such as ammonia, which then drives the turbine generator in a closed loop. In an open-cycle system, surface seawater is flash-evaporated in a vacuum chamber, and the resulting low-pressure steam drives a turbine-generator. Cold seawater is then used to condense the steam after it has passed through the turbine. The open cycle, therefore, can be configured to produce fresh water as well as electricity. 

Finally, vacuum-deposited organic photovoltaic cells were elaborated from a phthalocyanine/Ceo multilayer configuration. Such multilayer cells were constructed in a vacuum chamber coupled to an Ar-glove-box/characterization chamber. Sublimation purified copper phthalocyanine, C ), and bathocuprine were vacuum deposited on various cleaned and small molecule-modified ITO substrates, over which either PEDOT layers were spin casted, or were electrochemi-cally grown. 

The cell case is formed from an aluminum-polymer laminated film. The film is fusion bonded, the electrode stack is inserted, and the exterior case is fused by a heat or an ultrasonic sealing apparatus. The assembly then is checked for internal shorts, the moisture is removed by heating in a vacuum dryer, the electrolyte (polymer or conventional electrolyte depending upon the cell kind) is then injected, and the cell is vacuum-sealed in a two-chamber configuration. After formation, any gas formed is removed by a vacuum, the cell resealed, and the gas chamber discarded. Finally, the cell is subjected to... 

At the centre of any laser chemistry experiment is the reaction zone, on which normally all interest and instramental efforts are focused. Specific configurations of the reaction region, and the experimental apparams used, differ widely these depend on the namre of the chemical reactants, how they are prepared for interaction and what answers are sought in a particular investigation. Hence, in this chapter, the discussion of specific components (like vacuum chambers, flow systems, particle beam generation, etc.) are largely omitted (further details are given where specific examples are discussed in later chapters). 

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