This is a technical question. Suggest if any reference is there.
Hello Basanta Kumar Parida ,
Boiling is the process of converting a liquid to a vapor, where the vapor pressure (of the substance being boiled) matches the atmospheric pressure; vapor bubbles appear and grow in the liquid. Evaporation is the process of converting a liquid to a vapor, where the vapor pressure (of the substance evaporating) is, usually, much lower than the atmospheric pressure; no vapor bubbles usually appear. Note, in a vacuum, it is hard to distinguish boiling from evaporation. Evaporation can be accomplished in many ways. You have mentioned two ways to cause evaporation: Joule evaporation and E-beam evaporation, both of which are done in a vacuum. In Joule evaporation, a tungsten filament or boat has electric current passed through it to raise its temperature to cause, for example, aluminum hooks hanging from the filament to melt and evaporate. The aluminum vapor deposits itself on a cold substrate such as glass. One can also use an electron beam to evaporate highly refractory materials, such as quartz. The electron beam is aimed at a metal crucible containing the quartz, for example. The metal crucible has an electrical potential that is positive (making it the anode) with respect to that of the indirectly heated cathode (the filament heats the cathode, which is electrically isolated/insulated from the filament) or directly heat cathode (a so-called filament cathode). [1-3] discuss all these matters.
[1] L. Holland; Vacuum Deposition of Thin Films; John Wiley & Sons, Inc.; 1961; pp. 104-140 (Chapter 4 - Vapour Sources).
[2] O. S. Heavens; Optical Properties of Thin Solid Films; Dover Publications, Inc.; 1955; pp. 6-23 (Chapter 2 - The Formation of Thin Films).
[3] Gilbert W. Castellan; Physical Chemistry; Addison-Wesley; 1964; pp. 75-76. (Section 5-4 Vapor Pressure)
Regards,
Tom Cuff
Hi Basanta Kumar Parida ,
You are very welcome. See [4] for a discussion of how to employ glow discharges to improve adhesion of vapor deposited metal coatings on glass, for example.
[4] L. Holland; The Properties of Glass Surfaces; Chapman and Hall; 1966; pp. 310-334.
Regards,
Tom Cuff