Secondary ion emission from a KCl(0 0 1) surface by grazing-angle incidence of swift heavy ions

✍ Scribed by Kaoru Nakajima; Shigeharu Yamasaki; Motofumi Suzuki; Kenji Kimura

• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 190 KB
• Volume: 256
• Category: Article
• ISSN: 0168-583X
• DOI: 10.1016/j.nimb.2006.12.054

✦ Synopsis

The yield and the mass distribution of positive-charged secondary ions emitted from a KCl(0 0 1) surface were measured when MeV heavy ions were incident on the surface at grazing angles h i ranging from 1 to 5 mrad. Specular reflection of the projectile ions allowed us to investigate secondary ion emission originating from purely electronic excitation of an insulator surface. Single-charged secondary ions such as Cl + , K + , K þ 2 and small clusters, KðKClÞ þ n (n = 1-4) were detected for the incidence of 3 MeV O 2+ , while no secondary ions were detectable for the incidence of 1 MeV H + . The yield of secondary ions for the incidence of 3 MeV O 2+ slightly increased with the angle h i . The secondary ion production rate P(x) as a function of the distance x between the projectile and the surface atomic plane was derived from the h i -dependence of the yield. P(x) shows an overlinear dependence on the electronic stopping power S(x) for O ions specularly reflected in front of the surface.