THE SMOOTHING OF THE SURFACE-STRUCTURE IN SOLIDS UNDER IRRADIATION

The general system of equations describing the smoothing of surface st ructure in solids under irradiation is formulated. It is shown that un der real conditions the system can be reduced to a simpler form which has an exact solution. A general formula describing the smoothing of s urface structure with time is derived. As a special case, this formula gives the evolution (smoothing) of the relief in the absence of radia tion, which is associated with the difference in curvatures for differ ent roughnesses. The physical reason behind the intensification of smo othing under irradiation is the difference between the positions of th e centers of gravities for concentration profiles of vacancies and int erstitials. The radiation gives rise to a new type of dependence of th e rate of smoothing on the roughness parameters of the surface, which permits the experimental separation of the contribution from radiation to smoothing and simultaneously makes it possible to determine some p arameters which are difficult to measure. (C) 1997 American Institute of Physics.