Vapor cosine distribution

The material vaporized from a small area (point source) leaves the surface with a cosine distribution and thermal energies of a few tenths of an eV. The vaporized material arrives at a substrate surface having a mass per unit area dm dA) given by... 

Fig. 6. Cosine distribution of vaporized material from a point source (a) distribution of deposited material from a point source, and (b) distribution of film...

At aU but the lowest bombarding energies, the flux of atoms that are sputtered from the surface leaves the surface with a cosine distribution (Fig. 6). The sputtered atoms have kinetic energies higher than those of thermally vaporized atoms, as well as a high energy tail in the energy distribution that can be several tens of eV. 

Figure 3.4 Cosine Distribution of Particles Leaving a Point on a Surface. Top Relative Deposition on a Planar Surface from a Point Source of Vaporization. Bottom Relative Vaporization as a Function of Angle from Normal...

For low vaporization rates the flux distribution can be described by a cosine distribution. With no collisions in the gas phase, the material travels in a straight line between the source... 

Flux distribution (vaporization) The angular distribution of the particles leaving a vaporization source. See also Cosine distribution. 

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