Thermally sensitive at elevated, near 
melting point temperature, 
compound semiconductor materials single crystals including Group III-
Nitride, other Group III-V, 
Group II-VI and Group IV-IV are produced by a variety of methods. When produced as 
single crystal layers by 
epitaxy methods or is necessary to 
expose them to elevated temperatures or 
ion implanted to the non crystalline state, or their electrical or optical properties are modified, large numbers of 
crystal defects on the atomic or 
macro scale may be produced, which limit the yield and performance of opto- and electronic devices constructed out of and grown on top of these 
layers. It is necessary to be able to improve the 
crystal quality of such materials after being exposed to elevated temperature or 
ion implanted or modified by the presence of impurities. It is necessary, particularly for opto- and electronic devices that only the surface of such materials is processed, improved and thus the modified surface product. Generally, as shown in FIG. 1, the thermally sensitive 
compound semiconductor layer is first coated with a 
metal layer of approximate thickness of 0.1 microns. Next, the volatile component of the 
compound semiconductor is 
ion implanted through the 
metal layer so as to occupy mostly the top 0.1 to 0.5 microns of the compound 
semiconductor layer. Co-implantation may be used as well to improve the surface. Finally, through a pulsed directed energy beam of electrons with a 
fluence of approximately 1 
Joule  / cm2, the top approximately 0.5 microns acquire a level of the deposited 
metal and are converted into a 
single crystal with improved properties such as reduced defect density and or electrical 
dopant (FIG. 1).