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EM 902: A new for microanalysis with electron spectroscopic imaging (ESI) and EELS
Abstracts of The Netherlands Society for Electron Microscopy & Royal Microscopical Society
386
innumerable biological problems which are likely to gain from these new t e c h n i c a l and m e t h o d o l o g i c a l approaches. 1.
2. 3.
4.
5. 6.
E. Carlemalm, Ch. Colliex and E. Kellenberger, in: Advances in Electronics and Electron Physics (Academic Press, New York, 1984, in press). E. Carlemalm and E. Kellenberger, EMBO J. 1 (1982) 63-67. E. Carlemalm, J.-D. Acetarin, W. villiger, Ch. Colliex and E. Kellenberger, J. Ultrastruct. Res. 80 (1982) 339-43. R. M. Garavito, E. Carlemalm, Ch. Colliex and W. Villiger, J. Ultrastruct. Res. 80 (1982) 344-53. M. Adrian, J. Dubochet, J. Lepault and A. W. McDowall, Nature 308, 32-36. J. Dubochet, A. McDowall, B. Menge, E. M. Schmid and K. G. Lickfeld, J. Bact. 155 (1983) 381-90.
E M 902: A N E W T E M FOR M I C R O A N A L Y S I S WITH ELECTRON SPECTROSCOPIC IMAGING (ESI) AND EELS J. Bihr,
W.
Egle,
M. M e n z e l
and A. Rilk
Carl Z e i s s , E l e c t r o n O p t i c a l ments, D-7082 Oberkochen, W.
InstruGermany
M i c r o a n a l y s i s of thin specimens, i.e. the d e t e r m i n a t i o n of the spatial distrib u t i o n and c o n c e n t r a t i o n of b i o l o g i c a l l y r e l e v a n t atomic e l e m e n t s (P,S,N,O,Ca,Mg) can be c a r r i e d out m o s t e f f i c a c i o u s l y w i t h an e l e c t r o n s p e c t r o m e t e r that filters e n t i r e images in parallel. The new EM 902 i n c o r p o r a t e s such an imaging s p e c t r o m e t e r of the prismm l r r o r - p r i s m type. The range of m a g n i ficat i o n in e l e c t r o n s p e c t r o s c o p i c imaging = ESI a c c o m m o d a t e s o v e r v i e w s and also s a t i s f i e s the r e q u i r e m e n t for lattice imaging (0.344 nm). The range of s e l e c t a b l e e n e r g y losses (0-2000 eV) p r o v i d e s for e l e m e n t a l m a p p i n g and analysis for atoms via their K-, L- or h i g h e r shell absorptions. O p e r a t i o n of the EM 902 is that of a routine TEM. Very few a d d i t i o n a l steps are r e q u i r e d for energy a n a l y s i s or for e n e r g y - s e l e c t e d imaging. As an a d d e d b e n e f i t all b r i g h t field and dark field elastic images have an i n c r e a s e d contrast. E n e r g y - f i l t e r e d m i c r o g r a p h s are recorded photographically. Elemental maps are p r o d u c e d from two such e l e m e n t specific f i l t e r e d m i c r o g r a p h s via photographic s u b t r a c t i o n or c o m p u t e r - a s s i s t e d image processing. S p e c t r a are e v a l u a t e d w i t h similar but simpler m e t h o d s or can
be r e c o r d e d e l e c t r o n i c a l l y . The EM 902 also offers e l e c t r o n s p e c t r o s c o p i c d i f f r a c t i o n = ESD, prov i d i n g i n c r e a s e d c o n t r a s t of d i f f r a c t ion patterns but also d i s p e r s i o n relations of solids. C o n v e n t i o n a l TEM m e t h o d s are p o s s i b l e with no limitations. I n s t r u m e n t a l chara c t e r i s t i c s at 80 kV o p e r a t i o n are: S e l e c t a b l e e n e r g y loss range, O 2000 eV (max.); M a g n i f i c a t i o n range, 1 5 O x - 400,OOOx; C a m e r a length (diffraction), 390 mm - 2900 mm; Spatial r e s o l u t i o n (AE=O), 0.344 nm lattice, 0.5 nm p o i n t - t o - p o i n t ; Spatial r e s o l u t i o n (AE>O), >0.5 nm (the e x a c t r e s o l u t i o n is d e t e r m i n e d by the range of e l e c t r o n - m a t t e r interactions in the specimen); E n e r g y r e s o l u t i o n (90 m m ~ image), ± 7.5 eV (15 eV slit size); E n e r g y r e s o l u t i o n (spectrum), 2.5 eV (high current, small area); Jump ratio (Carbon k-edge), 20.
E N E R G Y LOSS E L E C T R O N S SCIENCE
IN M A T E R I A L S
M. H. L o r e t t o Department of Metallurgy and Materials, University of B i r m i n g h a m , Birmingham, U.K.
The d e v e l o p m e n t of a n a l y t i c a l electron m i c r o s c o p y over the last five or ten years has led to i n c r e a s e d a c t i v i t y in e l e c t r o n e n e r g y loss s p e c t r o s c o p y (EELS). In the main, m a n u f a c t u r e r s have chosen to add the e l e c t r o n spectrom e t e r b e l o w the n o r m a l v i e w i n g screen of m i c r o s c o p e s but at least one c o m m e r c i a l ly a v a i l a b l e d e s i g n now includes an e l e c t r o n s p e c t r o m e t e r as an integral part of the design. The s e p a r a t i o n of the e l e c t r o n s is done most c o m m o n l y by r a m p i n g the m a g n e t on the e l e c t r o n spect r o m e t e r so that the d i f f e r e n t e n e r g y e l e c t r o n s are d i s p e r s e d by the field and pass through a slit onto an e l e c t r o n detector. This series c o l l e c t i o n technique is i n e f f i c i e n t and c e r t a i n l y und e s i r a b l e if e l e c t r o n loss imaging is to be used and some p r o g r e s s has been made in using arrays of d e t e c t o r s w h i c h can c o l l e c t e l e c t r o n s of all energies simultaneously. The m a i n a p p l i c a t i o n of EELS has been in the a n a l y s i s of light e l e m e n t s w h i c h c a n n o t be d e t e c t e d u s i n g c o n v e n t i o n a l e n e r g y - d i s p e r s i v e X-ray a n a l y s i s (EDX)
386
innumerable biological problems which are likely to gain from these new t e c h n i c a l and m e t h o d o l o g i c a l approaches. 1.
2. 3.
4.
5. 6.
E. Carlemalm, Ch. Colliex and E. Kellenberger, in: Advances in Electronics and Electron Physics (Academic Press, New York, 1984, in press). E. Carlemalm and E. Kellenberger, EMBO J. 1 (1982) 63-67. E. Carlemalm, J.-D. Acetarin, W. villiger, Ch. Colliex and E. Kellenberger, J. Ultrastruct. Res. 80 (1982) 339-43. R. M. Garavito, E. Carlemalm, Ch. Colliex and W. Villiger, J. Ultrastruct. Res. 80 (1982) 344-53. M. Adrian, J. Dubochet, J. Lepault and A. W. McDowall, Nature 308, 32-36. J. Dubochet, A. McDowall, B. Menge, E. M. Schmid and K. G. Lickfeld, J. Bact. 155 (1983) 381-90.
E M 902: A N E W T E M FOR M I C R O A N A L Y S I S WITH ELECTRON SPECTROSCOPIC IMAGING (ESI) AND EELS J. Bihr,
W.
Egle,
M. M e n z e l
and A. Rilk
Carl Z e i s s , E l e c t r o n O p t i c a l ments, D-7082 Oberkochen, W.
InstruGermany
M i c r o a n a l y s i s of thin specimens, i.e. the d e t e r m i n a t i o n of the spatial distrib u t i o n and c o n c e n t r a t i o n of b i o l o g i c a l l y r e l e v a n t atomic e l e m e n t s (P,S,N,O,Ca,Mg) can be c a r r i e d out m o s t e f f i c a c i o u s l y w i t h an e l e c t r o n s p e c t r o m e t e r that filters e n t i r e images in parallel. The new EM 902 i n c o r p o r a t e s such an imaging s p e c t r o m e t e r of the prismm l r r o r - p r i s m type. The range of m a g n i ficat i o n in e l e c t r o n s p e c t r o s c o p i c imaging = ESI a c c o m m o d a t e s o v e r v i e w s and also s a t i s f i e s the r e q u i r e m e n t for lattice imaging (0.344 nm). The range of s e l e c t a b l e e n e r g y losses (0-2000 eV) p r o v i d e s for e l e m e n t a l m a p p i n g and analysis for atoms via their K-, L- or h i g h e r shell absorptions. O p e r a t i o n of the EM 902 is that of a routine TEM. Very few a d d i t i o n a l steps are r e q u i r e d for energy a n a l y s i s or for e n e r g y - s e l e c t e d imaging. As an a d d e d b e n e f i t all b r i g h t field and dark field elastic images have an i n c r e a s e d contrast. E n e r g y - f i l t e r e d m i c r o g r a p h s are recorded photographically. Elemental maps are p r o d u c e d from two such e l e m e n t specific f i l t e r e d m i c r o g r a p h s via photographic s u b t r a c t i o n or c o m p u t e r - a s s i s t e d image processing. S p e c t r a are e v a l u a t e d w i t h similar but simpler m e t h o d s or can
be r e c o r d e d e l e c t r o n i c a l l y . The EM 902 also offers e l e c t r o n s p e c t r o s c o p i c d i f f r a c t i o n = ESD, prov i d i n g i n c r e a s e d c o n t r a s t of d i f f r a c t ion patterns but also d i s p e r s i o n relations of solids. C o n v e n t i o n a l TEM m e t h o d s are p o s s i b l e with no limitations. I n s t r u m e n t a l chara c t e r i s t i c s at 80 kV o p e r a t i o n are: S e l e c t a b l e e n e r g y loss range, O 2000 eV (max.); M a g n i f i c a t i o n range, 1 5 O x - 400,OOOx; C a m e r a length (diffraction), 390 mm - 2900 mm; Spatial r e s o l u t i o n (AE=O), 0.344 nm lattice, 0.5 nm p o i n t - t o - p o i n t ; Spatial r e s o l u t i o n (AE>O), >0.5 nm (the e x a c t r e s o l u t i o n is d e t e r m i n e d by the range of e l e c t r o n - m a t t e r interactions in the specimen); E n e r g y r e s o l u t i o n (90 m m ~ image), ± 7.5 eV (15 eV slit size); E n e r g y r e s o l u t i o n (spectrum), 2.5 eV (high current, small area); Jump ratio (Carbon k-edge), 20.
E N E R G Y LOSS E L E C T R O N S SCIENCE
IN M A T E R I A L S
M. H. L o r e t t o Department of Metallurgy and Materials, University of B i r m i n g h a m , Birmingham, U.K.
The d e v e l o p m e n t of a n a l y t i c a l electron m i c r o s c o p y over the last five or ten years has led to i n c r e a s e d a c t i v i t y in e l e c t r o n e n e r g y loss s p e c t r o s c o p y (EELS). In the main, m a n u f a c t u r e r s have chosen to add the e l e c t r o n spectrom e t e r b e l o w the n o r m a l v i e w i n g screen of m i c r o s c o p e s but at least one c o m m e r c i a l ly a v a i l a b l e d e s i g n now includes an e l e c t r o n s p e c t r o m e t e r as an integral part of the design. The s e p a r a t i o n of the e l e c t r o n s is done most c o m m o n l y by r a m p i n g the m a g n e t on the e l e c t r o n spect r o m e t e r so that the d i f f e r e n t e n e r g y e l e c t r o n s are d i s p e r s e d by the field and pass through a slit onto an e l e c t r o n detector. This series c o l l e c t i o n technique is i n e f f i c i e n t and c e r t a i n l y und e s i r a b l e if e l e c t r o n loss imaging is to be used and some p r o g r e s s has been made in using arrays of d e t e c t o r s w h i c h can c o l l e c t e l e c t r o n s of all energies simultaneously. The m a i n a p p l i c a t i o n of EELS has been in the a n a l y s i s of light e l e m e n t s w h i c h c a n n o t be d e t e c t e d u s i n g c o n v e n t i o n a l e n e r g y - d i s p e r s i v e X-ray a n a l y s i s (EDX)