Satoshi Ninomiya oral presentation (PB1-Mon1-1-1)
Secondary ion yields produced by vacuum-type electrospray droplet ion beams
1 University of Yamanashi - Interdisciplinary Graduate School, 4-3-11 Takeda, 400-8511 Kofu, Japan
2 University of Yamanashi - Clean Energy Research Center, Takeda 4-3-11, 400-8511 Kofu, Japan
Electrospray droplet impact method based on atmospheric pressure electrospray technique (A-EDI) was developed as a new massive cluster ion beam source in our laboratory, and it has been successful in achieving efficient desorption/ionization of biological molecules, soft etching of polymers, and non-selective etching of metal oxides [1,2]. However, the current and brightness of the A-EDI beams were not practical for secondary ion mass spectrometry (SIMS) and X-ray photoelectron spectrospcopy (XPS). In order to improve the performance of this A-EDI gun, we are developing a new electrospray droplet ion beam gun using electrospray of aqueous solutions in a vacuum . This vacuum electrospray technique could be expected to be a high-intensity massive cluster beam source, and we are now evaluating the performance of the vacuum-type electrospray droplet ion (V-EDI) gun . In this study, the V-EDI gun was installed in the semi-commercial triple focus time-of-flight analyzer (TRIFT, ULVAC-PHI), and traditional liquid metal ion gun (Ga-LMIG) and gas cluster ion beam (Ar-GCIB) gun were also connected to the analyzer to directly compare the secondary ion yields. The secondary ion yields for some biological molecules produced by these monomer and cluster ion beams will be discussed.
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