the deposition of the organic material as a coating 14 in this case takes place by using an electron beam alternatively this coating can also be deposited by a different method fig1 c shows a detail x see fig1 b the defect is covered over a relatively large area by the coating 14 of organic material now according to the invention an electron beam which is not shown here is pointed at the immediate region around the defect 13 this region is represented by the field 15 in fig1 c the electron beam scans this field in rows and or columns which leads to hardening of the organic material the concentration gradient that is produced in the coating 14 results in the diffusion of organic molecules which are not yet reacted in the field 15 surface diffusion thus resulting in reinforcement of the hardening the diffusion of the molecules is illustrated by arrows in fig1 c the field 15 is illustrated in the hardened state in fig1 d the wide area coating and the subsequent diffusion means that there is no need to pass gases with extreme accuracy to the location to be repaired a certain residual amount of gas which is dependent on.