(Positron Annihilation Lifetime Spectroscopy; PALS) 1) 4) PALS

Transcription

1 A positron probe micro analyzer (PPMA) has been developed in AIST. When a positron microbeam is injected into a specimen, radiations including secondary electrons, back scattered positrons, and annihilation gamma-rays are emitted from the beam injected point. In the PPMA, these radiations are detected to characterize small area of specimens. We report on details of designs and specifications of the PPMA. Key words: positron probe micro analyzer, positron microscope, positron microbeam, positron annihilation lifetime spectroscopy 1. g Development of a Positron Probe Micro Analyzer with a High Intensity Positron Beam Nagayasu OH=>B6, Ryoichi SJOJ@>, Toshiyuki O=96>G6, and Atsushi K>CDBJG6 (Research Institute of Instrumentation Frontier (RIIF), National Institute for Advanced Industrial Science and Technology (AIST)) Takamitsu N6GJB> and Akira U:9DCD (Graduate School of Pure and Applied Science, University of Tsukuba) Masanori FJ?>C6B> (Department of Applied Chemistry, Chiba University) TEX: (45203) FAX: nagayasu-oshima@aist.go.jp (Positron Annihilation Lifetime Spectroscopy; PALS) 1)4) PALS PALS 1mm mm 5)7) (Positron Probe Micro Analyzer; PPMA) PPMA PALS (2008) 39

2 PPMA (RI) 12 PPMA PPMA 57) 8) 9) PPMA 2. PALS PALS PALS b RI 1) 1MBq 22 Na Na g (1.3 MeV) g (0.5 MeV) 200 ps PALS RI 23 mm (110 mm 2 ) RI b 0 E max b 17E max (MeV) 1.43 (cm 2 /g) 10) E max RI 1 MeV 22 Na 0.5 MeV r110 g/cm mm RI PALS mm 3 RI PALS 1mm 0.1 mm ev RI 200 ps 200 ps RI 40 (0.530 kev) PALS 40 E(keV) 1.6 /r (g/cm 3 )nm E0.530 kev 10 nm 1 mm 11) RI (0.11 GBq) 510 mm kev 10 3 mm 3 PALS ( 100 mm 2 ) RI 10 mm PALS 1 mm 2 3. PPMA PPMA (Electron Probe Micro Analyzer; EPMA) 12) PPMA EPMA 2 PPMA 2 g g PALS EPMA 2 PPMA MeV 100 pps 3 ma 1 mm X 13) ev 10 7 e /s RI 12

3 1 PPMA 2 1 ms 100 pps ms 1 ms ms 10 mm 0.1 mt 10 ev 1 ms ms 13) ns 2ns 150 MHz 300 ps 14), 15) mm 1mm 1mm 200 nm 200 ps 2 XY 2 MCPBaF 2 3 MCP 2 MCP BaF 2 g MCP PC 85 (2008) 41

4 5 (1) 3 PPMA 2 4(b) 10 16) 10 d2r d min 2r min r 2 min 2 E r a E e 2 /8mBr 2 2 a E (1) 4 2 (a) (b) (L 2 /L 1 ) PPMA 11) 4(a) (1/10) e m a E E B 5 5 E B E 0.11 ev E (in situ) B 1 1 1mT 6 PPMA (1) (E 0.1 ev, E10 kev, B1 mt, a0.1) d min 30 mm 5. PPMA MCP 1 7 MCP 1mm 1mm

5 6 1 1mT mm 7 1 MCP 1mm 9 PPMA Ta SiO ps 500 cps 2 Ta SiO ) Ta/SiO 2 8 E5 kev 100 mm PPMA 0.01 mm 2 PALS 100 mm kev 10 7 mm 3 10 mm RI PALS PPMA ps PALS 500 cps RI ps ) 10 ps 20/ 1,024 (32 pixel32 pixel) 6 6. PPMA 200 ps 500 cps PALS 85 (2008) 43

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