Growth of epitaxial dielectrics of II-A fluorides on Si and compound semiconductors has generated considerable research interest in recent years. In general, MBE and vacuum deposition techniques are being employed for the epitaxial growth of II-A fluorides on semiconductor substrate maintained between about 400 and 900°C during the deposition of dielectric material. With the typical deposition rate of about 1-2 Å/s, 8-10 minutes are required to deposit 1000 Å of dielectric material. This type of prolonged heating may not be suitable for future submicron and three-dimensional Si integrated circuits, as well as for compound semiconductor devices. We have developed a new reduced thermal budget (product of processing temperature and time) processing technique for the deposition of epitaxial dielectric films on Si and compound semiconductors. In this process, epitaxial dielectric is deposited in the e-beam system at room temperature and subsequently subjected to in-situ rapid isothermal processing by using incoherent light sources incorporated in the e-beam system. In this paper, electrical and structural characteristics of thin epitaxial dielectric films on Si are described.