Application of metal cluster complex ion beam for low damage sputtering

Abstract

Metal cluster complexes, including the colloidal metal cluster, were applied to establish the low damage sputtering method. Electro-spray-like ionization using an ink-jet nozzle has the potential to produce a cluster ion beam. A colloidal Au cluster of size 5 nm made a large crater-like hole at the carbon sheet.

Cluster SIMS using metal cluster complex ions

“…Fig. 1 shows examples of metal cluster complexes [12]. They are chemically synthesized organometallic compounds, which consist of a metallic framework of several metal atoms and surrounding ligands.…”

“…As metal cluster complexes, triosmium dodecacarbonyl, Os 3 (CO) 12 , and tetrairidium dodecacarbonyl, Ir 4 (CO) 12 , have been utilized; they have molecular weights of 906.7 and 1104.9, respectively [14]. As compared with other clusters such as SF 6 (MW = 146.1), Au 3 (MW = 590.9), and C 60 (MW = 720), these metal cluster complexes have higher molecular weights; hence, they are expected to be superior to conventional primary ion beams in SIMS.…”

“…Recently, we have proposed a metal cluster complex ion source of a new concept using metal cluster complexes [12]. Fig.…”

“…As compared with other clusters such as SF 6 (MW = 146.1), Au 3 (MW = 590.9), and C 60 (MW = 720), these metal cluster complexes have higher molecular weights; hence, they are expected to be superior to conventional primary ion beams in SIMS. Thus, after an initial test on silicon sputtering [15], we have performed SIMS analyses of inorganic and organic materials using Ir 4 (CO) 12 , thereby demonstrating that the metal cluster complex ion beam can improve depth resolution and secondary ion intensity in high-mass region [16][17][18]. In the present paper, after a brief description of the experimental apparatus and analytical samples, experimental results of sputtering characteristics of silicon and the SIMS analyses with the metal cluster complex ion, Ir 4 (CO) 7 + (MW = 964.9), are described.…”

Time‐of‐Flight secondary ion mass spectrometry (TOF‐SIMS) using the metal‐cluster‐complex primary ion of Ir4(CO)7+

“…[13] For these reasons, we had previously developed an ion source using massive compounds called metal-cluster-complexes, [14 -16] which are chemically synthesized organometallic compounds that consist of a metallic framework of several metal atoms and surrounding ligands. [14] As a metal-cluster-complex, tetrairidium dodecacarbonyl, Ir 4 (CO) 12 (1104.9 u), has been utilized. As compared with other clusters, such as SF 6 (146 u), Au 3 (591 u), and C 60 (720 u), it has a higher molecular weight; consequently, it is expected to be superior to conventional primary ions in SIMS.…”