J. Mass Spectrom. Soc. Jpn. Vol. 58, No. 5, 2010 REVIEW 9 Secondary Ion Mass Spectrometry (SIMS) SIMS SIMS Fundamentals of Mass Spectrometry Secondary Ion Mass Spectrometry (SIMS), Cluster SIMS, and Electrospray Droplet Impact SIMS Kenzo H>G6D@6 Kofu, YAMANASHI, JAPAN Clean Energy Research Center, University of Yamanashi, The use of secondary ion mass spectrometry (SIMS) to characterize inorganic, organic and biological materials has undergone significant and multiple advances in the past thirty years. Additional development in cluster ion sources that started in the early 1990s laid the ground work for the significant increase in SIMS investigations in material science. The continuing scaling trend leads to a drastic reduction in film thicknesses which increases the demands for very high depth resolution, ideally a multilayer system with the depth resolution in the order of 0.5 nm. Recently, the electrospray droplet impact (EDI) has been developed that uses the atmospheric pressure electrospray as a cluster ion source. EDI/SIMS is very high-sensitive and EDI is capable of very shallow surface etching without the damage left on the etched surface. In this chapter, the fundamentals and applications of EDI to the surface analysis are dealt with. (Received March 22, 2010; Accepted March 22, 2010) 1. (energy sudden) MALDI (matrix-assisted laser desorption ionization) FAB/ SIMS (fast atom bombardment/secondary ion mass spectrometry) SIMS 10 kev (cascade collision) Correspondence to: Kenzo H>G6D@6, Clean Energy Research Center, University of Yamanashi, Takeda 4 3 11, Kofu, Yamanashi 400 8511, JAPAN, e-mail: hiraoka@yamanashi. ac.jp 400 8511 4 3 11 SIMS SIMS SIMS 1) Fig. 1 15 kev Ga C 60 Ag 111 1) Ga (interlayer mixing) C 60 Ga C 60 175
K. Hiraoka Fig. 1. Ag 111 Ga C 60 1 2004, American Chemical Society. SIMS SIMS (Ar n ) Ar n (gas cluster ion beam: GCIB) 2) GCIB 2 3 2) GCIB (SIMS) 2) SIMS 3) 9) 2. /SIMS Fig. 2 /SIMS Fig. 2. EDI/SIMS SIMS electrospray droplet impact/sims EDI/SIMS 3) 9) Fig. 2 EDI XeFAB EDI 5mm Fig. 2 400 mm (heat bath) ms 50 20 176
SIMS SIMS SIMS Fig. 3. Rayleigh 5 2006, Wiley InterScience Fig. 2 m/z 10 4 5 10 4 Rayleigh 8 Rayleigh Rayleigh N (ge 0 R 3 ) 0.5 8p/e (1) g e 0 R m/z 10 4 5 10 4 m N (Fig. 3) 5) R 3 ((4/3)pR 3 ) Fig. 3 Rayleigh (u) N Rayleigh Rayleigh R 3 m 2 N 2 Fig. 3 m (m an 2 ) / ESI nanoesi ProbeElectrospray: 8 (FD) FD 8 Fig. 3 m/z 10 4 5 10 4 2 Rayleigh m 100 u 1,500 u N 60 300 Fig. 2 10 kv 1 na 2mm 2 10 9 cm 2 s 1 [(H 2 O) 90,000 100H] 100 Fig. 3 5) 10 nm 100 10 kv 10 6 ev u 12 km/s 5 3. Fig. 4 9 12 km/s 10 AÕ 10 13 (ps) EDI/SIMS ps MALDI ns ns ms EDI ps EDI MALDI EDI 177
K. Hiraoka Fig. 4. Fig. 5. 1 M 5 2006, Wiley InterScience. EDI EDI 4. Fig. 2 10 nm 100 ev 1M EDI (Fig. 5) 5) H (H 2 O) n m/z 3,000 10 nm 100 ev 1 EDI MALDI EDI 5. EDI 178
SIMS SIMS SIMS Fig. 6. 100 10 C 60 EDI 4) Fig. 7. 10 S 100 c EDI 4 2006, Wiley InterScience. Fig. 6 100 10 C 60 EDI C 60 C 60 C 60 (2) C 60 C 60 C 60 C 60 (2) EDI Fig. 7 10 S 100 c EDI S [M H] 10 30 1 c m/z 10,000 EDI 12 km/s 1 10 (useful yield) H 2 O H 2 O H 3 O OH M H 3 O M H 2 O [M H] OH M H 2 O [M H] MALDI 179
K. Hiraoka Fig. 8 EDI MALDI EDI MALDI MALDI PE (phosphatidylethanolamine) PS (phosphatidylserine) EDI PI (phosphatidylinositol) ST (sulfatide) EDI Fig. 8. EDI MALDI 3 2006, Springer- Verlag. OH PE PS EDI MALDI 10 MALDI 6. EDI 1 FK506 Fig. 9 Fig. 9(a) FK506 EDI EDI (b), (c) (d) Fig. 2 Xe FAB XeFAB (5 kev) FAB (b) (c) 10 Xe (d) 20 XeFAB 20 XeFAB FK506 (e) (a) FAB EDI EDI Fig. 10 Au S (CH 2 ) 6 NH 2 EDI 9) H S (CH 2 ) 6 NH 2 Fig. 9. 1 FK506 (a) EDI (b) XeFAB (5 kev) FAB (c) 10 XeFAB (5 kev) FAB (d) 20 XeFAB (5 kev) FAB (e) 20 XeFAB EDI 3) 3 2006, Springer-Verlag. 180
SIMS SIMS SIMS Fig. 10. Au S (CH 2 ) 6 NH 2 0 15 EDI [M H] [2M H] [M H Au] Au Fig. 11. PET 0.1 mm EDI (a) (b) 60 [(CH 3 COOH) 2 H] (m/z 121) [(CH 3 COOH) 3 H] (m/z 181) 181
K. Hiraoka Au Au EDI Fig. 11 0.1 mm (PET) EDI (a) (b) 60 PET (a) (b) EDI 60 PET EDI 60 PET 4 1 Fig. 12. (a) PET (0.1 mm) EDI XPS O1s (b) PET (0.1 mm) EDI XPS C1s (c) PET (0.1 mm) 1keV Ar XPS O1s Ar (d) PET (0.1 mm) 1 kev Ar XPS O1s Ar BE: (binding energy) (ev) EDI Ar PET 70 nm 120 10 nm 8.3 182
SIMS SIMS SIMS X (X-ray photoelectron spectroscopy: XPS) EDI/SIMS XPS Fig. 12(a) (b) EDI PET O1s C1s 120 PET Ar PET Ar XPS Ar 1keV Fig. 12(c), (d) Ar O1s COO CO C1s Ar PET CC C1s Ar PET (Fig. 10) (Fig. 12(a), (b)) 120 PET (atomic force microscopy) 2nm 120 16 nm (ripple) 30 10), 11) EDI EDI Fig. 10 15 EDI Au Au n EDI Fig. 13 3keV Ar (InP) (AFM) 0.8 nm 3 kev Ar 60 SiO 2 60 nm 16.7 nm 1 Fig. 13(b) Ar In SiO 2 42 nm EDI 1.2 nm XPS Ar (b) InP P In (In/P 1.7) EDI (c) InP In/P 1 EDI InP In P 7 SIMS SIMS useful yield: 0.01 EDI EDI 100 ev Fig. 13. InP AFM (2 2 mm 2 ) (a) EDI (b) 3 kev Ar 30 SiO 2 60 nm (c) EDI 240 SiO 2 48 nm 183
K. Hiraoka H 2 O H 2 O H 2 O 3 2 EDI EDI/SIMS 1. 2. MeV 3. EDI 4. EDI self-cleaning 5. EDI 6) 6. EDI SIMS EDI/SIMS XPS, AES (Auger electron spectroscopy), SPM (Scanning probe microscopy) 1) Z. Postawa, B. Czerwinski, M. Szewczyk, E. J. Smiley, N. Winograd, and B. J. Garrison, J. Phys. Chem. B, 108, 7831 (2004). 2) (2006). 3) K. Hiraoka, D. Asakawa, S. Fujimaki, A. Takamizawa, and K. Mori, Eur. Phys. J. D, 38, 225 (2006). 4) K. Hiraoka, K. Mori, and D. Asakawa, J. Mass Spectrom., 41, 894 (2006). 5) K. Mori, D. Asakawa, J. Sunner, and K. Hiraoka, Rapid Commun. Mass Spectrom., 20, 2596 (2006). 6) D. Asakawa, S. Fujimaki, Y. Hashimoto, K. Mori, and K. Hiraoka, Rapid Commun. Mass Spectrom., 21, 1579 (2007). 7) I. Kudaka, D. Asakawa, K. Mori, and K. Hiraoka, J. Mass Spectrom., 43, 436 (2008). 8) K. Mori and K. Hiraoka, Int. J. Mass Spectrom., 269, 95 (2008). 9) D. Asakawa, K. Mori, and K. Hiraoka, Appl. Surf. Sci., 255, 1217 (2008). 10) Y. Homma, A. Takano, and Y. Higashi, Appl. Surf. Sci., 203 204, 35 (2003). 11) T. K. Chini, F. Okuyama, M. Tanemura, and K. Nordland, Phys. Rev. B, 67, 205403 (2003). Keywords: SIMS, Cluster SIMS, Electrospray droplet impact, Supersonic collision, Shock wave 184