Surface morphology of CaF₂ film grown up to 500 Å thickness on a Si(111) 7×7 substrate in the temperature range from room temperature (RT) to 700^oC has been observed by atomic force microscopy (AFM) and reflection high-energy electron diffraction (RHEED). It was found that three dimensional (3 D) islands of CaF₂ were grown at RT, however, relatively flat surface appears at over 300^oC. Especially, at a high temperature of 700^oC, equilateral triangular shape islands with wide flat terrace were formed. On the other hand, desorption process of the CaF₂ film due to electron stimulated desorption (ESD) was also investigated. It was found as a remarkable point that equilateral triangular shape craters were formed on the film surface at 300^oC by ESD.