Pulsed metal-ion beams for modifications of solids

The modification of surface properties of materials with high-intensity pulsed ion beams has been studied for over a decade [1,2]. The transient heat generation by HIPIB in a near surface region may cause variety of the processes, e.g. crystalline defects annealing, mixing, glazing, quenching etc. [3,4]. For the modification of a material surface particularly interesting conditions are created in a case when the transient heat transfer is connected with the mass transport into a substrate during the same pulse. A high temperature of the surface region (up to the melting point and above) and the transient nature of the heat evolution create unique conditions for the interaction between host and deposited materials, during which various metastable phases and alloys can be formed. Such conditions can be obtained within IONOTRON-type generators which were developed at SINS for the investigations of controlled thermonuclear fusion [5]. Intense ion-plasma beams generated by those facilities have energy densities ranging from 1 to 10 J/cm² and pulse length within a microsecond range. These beams are capable to melt a near-surface layer of any material and to dope with doses of the order of 10¹⁴ to 5×10¹⁷ atoms/cm².